Luminous Landscape Forum
Equipment & Techniques => Digital Cameras & Shooting Techniques => Topic started by: dreed on March 29, 2010, 09:16:56 am
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I seem to recall seeing photos, such as those of space shuttle launches, where the ISO of the film used was 25. No, that's not a mistake, ISO 25. Why? Because the takeoff is a very very bright event, when you're close up. But doesn't a really fast shutter make up for that? In this case, yes, but not all...
Recently I was sitting on the rocks of a stream, during daylight hours, trying to get the "smooth water" effect. But even at ISO 100, using a high grade polarising lens, it's just too bright. With a bit of research, it seems that the trick these days is to use a rather dark filter. This cost of this approach is a(nother) bit of glass in front of the lens, potentially having a negative impact on your image quality (think of Reichman's notes about how the UV/haze filter of today really doesn't add any value and that it's like shooting through a window.)
Of course, the f-stop can be reduced down to, say, f/22 or smaller, but this too can have an impact on image quality due to diffraction and airy discs.
This all got me thinking and wondering if in the pursuit of high ISO perfection in low light, we're hurting ourselves at the other end and we just haven't realised this. For instance, various DSLRs now have a minimum ISO of 200. Those "smooth water" shorts are now going to require more effort than before this.
Of course ISO 25 is not going to be of benefit to those great big white lens folks that walk around sporting events nor the paparazi flooding a star with flashes at an interview. Nor is it going to help parents at their children's party or sporting event on the weekend. But now that the "film" is part of the camera body, for those that became used to low ISO with landscape photography, it seems like that choice has been removed. And whilst some cameras today are sold with ISO 50 capability, analysis seems to suggest that this is just a corrected, underexposed photo at ISO 100.
Comments?
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I seem to recall seeing photos, such as those of space shuttle launches, where the ISO of the film used was 25. No, that's not a mistake, ISO 25. Why? Because the takeoff is a very very bright event, when you're close up. But doesn't a really fast shutter make up for that? In this case, yes, but not all...
Recently I was sitting on the rocks of a stream, during daylight hours, trying to get the "smooth water" effect. But even at ISO 100, using a high grade polarising lens, it's just too bright. With a bit of research, it seems that the trick these days is to use a rather dark filter. This cost of this approach is a(nother) bit of glass in front of the lens, potentially having a negative impact on your image quality (think of Reichman's notes about how the UV/haze filter of today really doesn't add any value and that it's like shooting through a window.)
Of course, the f-stop can be reduced down to, say, f/22 or smaller, but this too can have an impact on image quality due to diffraction and airy discs.
This all got me thinking and wondering if in the pursuit of high ISO perfection in low light, we're hurting ourselves at the other end and we just haven't realised this. For instance, various DSLRs now have a minimum ISO of 200. Those "smooth water" shorts are now going to require more effort than before this.
Of course ISO 25 is not going to be of benefit to those great big white lens folks that walk around sporting events nor the paparazi flooding a star with flashes at an interview. Nor is it going to help parents at their children's party or sporting event on the weekend. But now that the "film" is part of the camera body, for those that became used to low ISO with landscape photography, it seems like that choice has been removed. And whilst some cameras today are sold with ISO 50 capability, analysis seems to suggest that this is just a corrected, underexposed photo at ISO 100.
Comments?
With a high-quality neutral density filter, your problems are solved. A high quality filter won't degrade the image.
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Hi,
The sensors essentially have a natural sensivity, there are only two ways to reduce it:
1) Putting an ND filter in front
2) Using a color grid array with sharper cut off filters.
It may be possible to make a sensor without microlenses, but that would only decrease sensitivity by one stop, or so.
The Leica S2 has a native ISO of 160, too. They have an option to "pull" but that's probably just overexposure.
Best regards
Erik
I seem to recall seeing photos, such as those of space shuttle launches, where the ISO of the film used was 25. No, that's not a mistake, ISO 25. Why? Because the takeoff is a very very bright event, when you're close up. But doesn't a really fast shutter make up for that? In this case, yes, but not all...
Recently I was sitting on the rocks of a stream, during daylight hours, trying to get the "smooth water" effect. But even at ISO 100, using a high grade polarising lens, it's just too bright. With a bit of research, it seems that the trick these days is to use a rather dark filter. This cost of this approach is a(nother) bit of glass in front of the lens, potentially having a negative impact on your image quality (think of Reichman's notes about how the UV/haze filter of today really doesn't add any value and that it's like shooting through a window.)
Of course, the f-stop can be reduced down to, say, f/22 or smaller, but this too can have an impact on image quality due to diffraction and airy discs.
This all got me thinking and wondering if in the pursuit of high ISO perfection in low light, we're hurting ourselves at the other end and we just haven't realised this. For instance, various DSLRs now have a minimum ISO of 200. Those "smooth water" shorts are now going to require more effort than before this.
Of course ISO 25 is not going to be of benefit to those great big white lens folks that walk around sporting events nor the paparazi flooding a star with flashes at an interview. Nor is it going to help parents at their children's party or sporting event on the weekend. But now that the "film" is part of the camera body, for those that became used to low ISO with landscape photography, it seems like that choice has been removed. And whilst some cameras today are sold with ISO 50 capability, analysis seems to suggest that this is just a corrected, underexposed photo at ISO 100.
Comments?
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With a high-quality neutral density filter, your problems are solved. A high quality filter won't degrade the image.
I agree ... I don't see any noticeable image degradation at all with my B&W ND filter.
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I always used to complain in the other direction back in the film days ...
I shot a lot of Plus-X ... and always used to fantasize about a film that would look like Plus-X at ISO 800.
I guess the grass is always greener ...
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I have never had the need to use an ND filter in my work - but thinking about it, doesn't using a heavy one make focussing ever more difficult because of the darkened screen if using a reflex camera? I don't look sympathetically on the idea of focussing first and screwing filters on after the event!
It's my guess that the digital answer is really going to lie in two types of more specialized cameras: those for sport and reportage and the alternatives for fine art. The way price is going, it seems to me that such alternatives are quite feasible - people already seem willing to pay mega bucks for what's currently available; a finer tuning shouldn't go amiss.
Rob C
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I have never had the need to use an ND filter in my work - but thinking about it, doesn't using a heavy one make focussing ever more difficult because of the darkened screen if using a reflex camera?
That's where live view REALLY comes in handy ... the LCD monitor corrects for that.
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I saw an enormous 35mm B&W portrait print made with giga film 25iso if I remember, impressive! I mean, impressive.
That would be nice a 25 iso in digital, definitely.
Fred.
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You can get ISO 50 with Canon Extended. I've used it to cut light a couple of times. I then bought a Hoya Pro level ND filter worth 3 stops. Used with my B&W polarizer, I get 4.5 stops. Recently, that combo wasn't enough. So, I just purchased a Hoya Pro level ND filter worth 6 stops! They also have one at 9 stops.
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I saw an enormous 35mm B&W portrait print made with giga film 25iso if I remember, impressive! I mean, impressive.
That would be nice a 25 iso in digital, definitely.
There is a big confusion here due to the fact that what people usually mean by the ISO speed of a sensor is very different than what is meant by the ISO speed of a film: sensor base ISO speed is a lower exposure index limit based on highlight handling, while film ISO speed is an upper exposure index limit based on a standard of adequate shadow to midtone handling.
Roughly, the ISO speed of a film is the highest exposure index (least amount of exposure) that the film needs to meet some standard of shadow handling four stops below the mid-tones: a shadow based upper limit on exposure level. Films also have another, lower exposure index which is the minimum to which the film can be "pulled" while still handling highlights sufficiently: a highlight based lower limit on exposure level.
The base ISO of a sensor is like this latter "pull processing limit": the lowest ISO setting that handles highlights adequately (up to about 3 stops above mid-tones). On the other hand, the "film ISO speed equivalent" of a DSLR sensor, the maximum at which shadows are "adequately" handled, is usually far higher: maybe 1600 to 3200 or even beyond for current SLR sensors. This higher "shadow based" figure, not the base or minimum safe ISO speed, is the natural counterpart of the ISO speed rating of a film, so modern DLSR sensors are really like about ISO 1600 film that can be pull processed down to about ISO 100 to 200 before the highlights get blown too much by over-full photosites. (And if a DSLR is used at this "film ISO like" exposure level, highlight handling can be a lot better than it is when the emphasis is on gathering as much light as possible to control shadow noise, in ETTR fashion --- a somewhat neglected trade-off!)
With low speed films, finer grain and higher resolution is achieved in a way that reduces the "shadow based" ISO speed. The digital equivalent is reducing pixel size which again reduces the maximum noise-limited ISO speed --- but this does not reduce the base ISO speed. Most causes of lower base ISO involve "wasting light", such as with ND filters or omitting micro-lenses or just the plain less efficient technologies of older sensors. Such routes to lower base ISO speed are more or less unrelated to improved resolution, so there is very little interest in doing it with sensors. There are a few better options, like
(a.) increasing well capacity at equal pixel spacing, such as with deeper photosites, and maybe with full frame type CCD vs active pixel CMOS sensors.
(b.) a mix of highlight and shadow photosites such as in some of Fujifilm's Super CCD sensors, which is like having tiny ND filters over half of the photosites. Gone from the SLR market though.
I agree that this is yet another advantage of Live View: allowing ND filter use without dimming the VF image. An alternative is an internal ND filter near the sensor, not in the light path of the OVF. Another alternative is a rangefinder VF, or any non-SLR VF. Some compact digicams have ND filters that are rotated in front of the sensor to simulate high f-stops, and which do not effect the brightness of the image in either the EVF or the optical non-SLR viewfinder. They do this instead of stopping down too far, to avoid excessive diffraction effects. That is, the f/16 on some digicams is really f/8 with two stops of ND filter.
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ISO only gets you so far if trying to achieve a longish exposure in bright light; you're probably still going to need a filter, just not quite as strong of one. There's a pretty small window of exposures where ISO 25-50 would let you shoot without a filter but ISO 100-200 requires a filter. I can't see this being much of a consideration in camera choice for landscape/nature photographers, because the shots where you're most likely to want long exposures tend to work best when shot in lower light levels anyway (waterfalls/creeks in overcast night, lapping ocean waves at twilight, etc).
My current camera has a base ISO of 100. I'd much rather it were 200 than 25 of 50, personally. Adding an ND filter when you need a slower shutter speed is most definitely preferable to raising the ISO to get a faster one, and I'm more likely to want a faster shutter speed if I can get it anyway.
It's more of a legitimate issue for location photographers using strobes, who need to be able to over-power the ambient light while still staying under their flash-sync speed.
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You can get ISO 50 with Canon Extended. I've used it to cut light a couple of times.
Not really. Canon's ISO50 is fake ISO. I.e. you obtain exactly the same RAW data at ISO50 than shooting at ISO100 with the same aperture and shutter. This has been proved and discussed several times in the forum.
When shooting JPEG, ISO50 can be useful though because the camera will do a -1EV exposure adjustment for you, so that the ISO100 RAW will render as a ISO50 JPEG. But if you clipped the highlights in the RAW file, they will be gone, so it will never be a genuine ISO50 JPEG.
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[quote name='Rob C' date='Mar 29 2010, 07:32 PM' post='356686']
I have never had the need to use an ND filter in my work - but thinking about it, doesn't using a heavy one make focussing ever more difficult because of the darkened screen if using a reflex camera? I don't look sympathetically on the idea of focussing first and screwing filters on after the event!
Unquote.
In my limited experience of using ND filters anything less than a 10 stop can be auto focused. As to screwing on filters then you do get used to it. This type of photography involves patience. The only problem is that inevitably you are likely to drop the filter somewhere where you wouldn't want it to go?
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Comments?
This will give you ISO 6.
http://cgi.ebay.com/Kodak-DCS-Pro-SLR-n-Di...=item19baff5a63 (http://cgi.ebay.com/Kodak-DCS-Pro-SLR-n-Digital-Camera-13-9-MP-Nikon-Mount_W0QQitemZ110511479395QQcmdZViewItemQQptZDigital_Cameras?hash=item19baff5a63)
You end up paying only 160 US$ per ISO, whatever that means...
Cheers,
Bernard
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I'm not technical expert but as I understand it the sensor manuf must make a decision on the base iso sensitivity of the sensor. If they go for a low iso, high iso (which is increased gain) performance will suffer. If they go for a higher iso, you don't get the low iso speed available without 'fake' iso settings.
Given these tradeoffs I'd take high iso performance any day of the week; getting rid of light is easier than trying to get more. In 2 years of using the Nikon D700 (base iso 200) the only occasion I even reach for the ND filter is getting shallow dof with flash due to the sync speed issue, but even then the iso 200 base means I can shoot noise free with less flash power inside saving battery power and recycle time or get more range.
The only people I can think of who care about this are photogs that use flash in bright light (fashion, wedding) or people that love shooting these milky moving water pictures both of these specific siatuations can be dealt with with ND filters.
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The truth is that we are still waiting to see some sort of visual revolution in images from high ISO performance that photographers said they needed so much before they bought their latest Nikon's and Canon's. That photographers now need low ISO performance is pretty well in the same ballpark, in that photographers soon forget all the things they needed and make the same old photographs anyway.
Steve
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The truth is that we are still waiting to see some sort of visual revolution in images from high ISO performance that photographers said they needed so much before they bought their latest Nikon's and Canon's. That photographers now need low ISO performance is pretty well in the same ballpark, in that photographers soon forget all the things they needed and make the same old photographs anyway.
I don't think there was ever going to be a 'visual revolution' with a few stops of improvement in high iso performance and no on promised one. You could shoot film at 6400 just like you can shoot a dslr at 6400 but what is does mean is that pictures that were once taken in these situations with loads of noise and fell apart at anything over 6x4" can now look very good printed to make larger sizes which is great for both photographers and clients.
Ask any good wedding photographer what high iso has done for them during church ceremonies where no flash is allowed.
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There is a big confusion here due to the fact that what people usually mean by the ISO speed of a sensor is very different than what is meant by the ISO speed of a film: sensor base ISO speed is a lower exposure index limit based on highlight handling, while film ISO speed is an upper exposure index limit based on a standard of adequate shadow to midtone handling.
Roughly, the ISO speed of a film is the highest exposure index (least amount of exposure) that the film needs to meet some standard of shadow handling four stops below the mid-tones: a shadow based upper limit on exposure level. Films also have another, lower exposure index which is the minimum to which the film can be "pulled" while still handling highlights sufficiently: a highlight based lower limit on exposure level.
The base ISO of a sensor is like this latter "pull processing limit": the lowest ISO setting that handles highlights adequately (up to about 3 stops above mid-tones). On the other hand, the "film ISO speed equivalent" of a DSLR sensor, the maximum at which shadows are "adequately" handled, is usually far higher: maybe 1600 to 3200 or even beyond for current SLR sensors. This higher "shadow based" figure, not the base or minimum safe ISO speed, is the natural counterpart of the ISO speed rating of a film, so modern DLSR sensors are really like about ISO 1600 film that can be pull processed down to about ISO 100 to 200 before the highlights get blown too much by over-full photosites. (And if a DSLR is used at this "film ISO like" exposure level, highlight handling can be a lot better than it is when the emphasis is on gathering as much light as possible to control shadow noise, in ETTR fashion --- a somewhat neglected trade-off!)
With low speed films, finer grain and higher resolution is achieved in a way that reduces the "shadow based" ISO speed. The digital equivalent is reducing pixel size which again reduces the maximum noise-limited ISO speed --- but this does not reduce the base ISO speed. Most causes of lower base ISO involve "wasting light", such as with ND filters or omitting micro-lenses or just the plain less efficient technologies of older sensors. Such routes to lower base ISO speed are more or less unrelated to improved resolution, so there is very little interest in doing it with sensors. There are a few better options, like
(a.) increasing well capacity at equal pixel spacing, such as with deeper photosites, and maybe with full frame type CCD vs active pixel CMOS sensors.
(b.) a mix of highlight and shadow photosites such as in some of Fujifilm's Super CCD sensors, which is like having tiny ND filters over half of the photosites. Gone from the SLR market though.
I agree that this is yet another advantage of Live View: allowing ND filter use without dimming the VF image. An alternative is an internal ND filter near the sensor, not in the light path of the OVF. Another alternative is a rangefinder VF, or any non-SLR VF. Some compact digicams have ND filters that are rotated in front of the sensor to simulate high f-stops, and which do not effect the brightness of the image in either the EVF or the optical non-SLR viewfinder. They do this instead of stopping down too far, to avoid excessive diffraction effects. That is, the f/16 on some digicams is really f/8 with two stops of ND filter.
Thanks for this extended and interesting technical explaination.
So, how can be acheived the equivalent (or something close) to what could be done with the Pan films with digital? (in term of rendering and resolution?)
Something is not clear for me there.
Fred.
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Thanks for this extended and interesting technical explaination.
So, how can be acheived the equivalent (or something close) to what could be done with the Pan films with digital? (in term of rendering and resolution?)
Something is not clear for me there.
Fred.
Just because ISO-25 films had better resolution than higher-ISO films, doesn't mean that we're missing something by having DSLR's with higher native ISO's. Digital is a completely different beast. What exactly are you wanting to achieve that you don't think you can do with digital?
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Just because ISO-25 films had better resolution than higher-ISO films, doesn't mean that we're missing something by having DSLR's with higher native ISO's. Digital is a completely different beast. What exactly are you wanting to achieve that you don't think you can do with digital?
Jeff,
I think we can acheive almost everything in digital.
My point was a question that reflects my ignorance on how to get close to the look of these Pan film with digital.
I know it can be done, I just can't find how.
Fred.
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I don't think there was ever going to be a 'visual revolution' with a few stops of improvement in high iso performance and no on promised one. You could shoot film at 6400 just like you can shoot a dslr at 6400 but what is does mean is that pictures that were once taken in these situations with loads of noise and fell apart at anything over 6x4" can now look very good printed to make larger sizes which is great for both photographers and clients.
Ask any good wedding photographer what high iso has done for them during church ceremonies where no flash is allowed.
Twas sarcasm that a visual revolution would evolve from buying an essential new camera......
For anybody that needs a new camera, try this crazy idea
Crazy Idea (http://www.pixelatedimage.com/blog/2010/03/a-crazy-idea/)
Steve
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The truth is that we are still waiting to see some sort of visual revolution in images from high ISO performance that photographers said they needed so much before they bought their latest Nikon's and Canon's. That photographers now need low ISO performance is pretty well in the same ballpark, in that photographers soon forget all the things they needed and make the same old photographs anyway.
Your post reminded me of this excellent article (http://www.largeformatphotography.info/chasing-magic-bullet.html).
Cheers,
Bernard
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This will give you ISO 6.
http://cgi.ebay.com/Kodak-DCS-Pro-SLR-n-Di...=item19baff5a63 (http://cgi.ebay.com/Kodak-DCS-Pro-SLR-n-Digital-Camera-13-9-MP-Nikon-Mount_W0QQitemZ110511479395QQcmdZViewItemQQptZDigital_Cameras?hash=item19baff5a63)
You end up paying only 160 US$ per ISO, whatever that means...
Cheers,
Bernard
I was about to mention the Kodak, I just sold one. The Kodaks low iso settings were not like conventional settings, you had a matrix of shutter speeds that had to be used. I don't know what Kodak did but the low iso settings produced wonderful results.
I can see an argument for 25 or 50 iso if they produced superior results, otherwise I can't think of a genuine need.
Kevin.
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This will give you ISO 6.
http://cgi.ebay.com/Kodak-DCS-Pro-SLR-n-Di...=item19baff5a63 (http://cgi.ebay.com/Kodak-DCS-Pro-SLR-n-Digital-Camera-13-9-MP-Nikon-Mount_W0QQitemZ110511479395QQcmdZViewItemQQptZDigital_Cameras?hash=item19baff5a63)
You end up paying only 160 US$ per ISO, whatever that means...
Cheers,
Bernard
Hi Bernard,
What do you mean ISO 6 ??
Is that Kodak really a good camera? it has been hardly critisized everywhere.
Fred.
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Canon's ISO50 is fake ISO.
I understand that the ISO 50 has somewhat limited highlight headroom, so is "pulling" a bit further than is safe in some situations, though it seems fine when there is not too much subject brightness range between metered mid-tones and highlights: about 2 1/2 stops or less.
But can you explain the difference between "fake ISO" and "real ISO"? As far as I can tell, the only meaning of the ISO setting on a digital camera is exposure index, indicating the amount of light (subject brightness times exposure duration) needed to get a suitable "mid-tone signal level" in the final digital output. All ISO settings are equally real as exposure index values, as far as I can tell, even ones with limited highlight headroom or noisy shadows.
Some people seem to use "real ISO" for the effects of varying the gain in the analog domain, and "fake ISO" for similar effects achieved in the digital domain, as if variable analog gain (with its associated amp. noise) is "real" and "good", while variable digital scaling of levels (a perfectly noise free process) is "fake" and "bad". I do not see how this dichotomy is justified.
Each approach to adjusting the final signal level has its advantages, and my imaginary ideal camera would have a fixed amplification (enough to get the sensor dark noise level comfortably above the level all downstream noise sources), and an ADC that can handle that signal even with full-well output, and then ISO adjustment done digitally, to avoid any noise from variable gain in analog processing. So all ISO adjustments would be "fake"!
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But can you explain the difference between "fake ISO" and "real ISO"? As far as I can tell, the only meaning of the ISO setting on a digital camera is exposure index, indicating the amount of light (subject brightness times exposure duration) needed to get a suitable "mid-tone signal level" in the final digital output. All ISO settings are equally real as exposure index values, as far as I can tell, even ones with limited highlight headroom or noisy shadows.
There is more to ISO than that. Look at the following diagram:
(http://www.guillermoluijk.com/article/iso/modelo.gif)
In the digital pipeline, the ISO adjustment controls the gain of an amplifier that works after the sensor captures light. Aperture and shutter control the amount of light (photons) that hit the sensor. ISO comes next, and controls the amplification of the analog signal obtained, and this amplification has very important consequences both in the signal to noise ratio and highlights headroom.
When setting ISO50 on a Canon 5D, the amplifier will internally work at the ISO100 gain. If you read carefully and understand the following, you will see clear that using ISO50 doesn't add anything to the RAW shooter: for a given aperture and shutter, the RAW data (i.e. the digital values contained in the RAW file) will be exactly the same, no matter if we set ISO50 or ISO100 on the camera.
It will be the camera display and commercial RAW developers that, according to the RAW file metadata informing about the ISO50 setting, will lie to us by displaying the ISO50 image one stop darker. But the RAW data itself will be exactly the same, both numerically and qualitatively (signal to noise ratio).
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Jeff,
I think we can acheive almost everything in digital.
My point was a question that reflects my ignorance on how to get close to the look of these Pan film with digital.
I know it can be done, I just can't find how.
Fred.
You can get the high noise-free res of pan films (I used Pan F in Hasselblads) with quality high-res MF digital cameras.
What limits ISO is the size of the pixel (or of the sensitive area or micro-lens of the pixel)...
So bigger pixels give you higher ISO.
Each pixel can sense a limited number of photons and record the signal from them before the signal store is full.
Smaller pixels give you higher res (per unit area) and lower ISO (as they sense fewer photons).
The smallest practicable pixel (pitch) is about 2 microns, as the wavelength of light is .4 to .7 microns.
So, if a 6 Micron pixel has a lower limit of ISO = 50, a 2 micron pixel, with 1/9th the area, might give you ISO 15 and the best res per area (and consequently the best DOF for the res).
In a very small pixel there is very little room for data storage, so the max ISO of a 2 micron pixel would make it unmarketable in this high-ISO mad world.
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You can get the high noise-free res of pan films (I used Pan F in Hasselblads) with quality high-res MF digital cameras.
What limits ISO is the size of the pixel (or of the sensitive area or micro-lens of the pixel)...
So bigger pixels give you higher ISO.
Each pixel can sense a limited number of photons and record the signal from them before the signal store is full.
Smaller pixels give you higher res (per unit area) and lower ISO (as they sense fewer photons).
The smallest practicable pixel (pitch) is about 2 microns, as the wavelength of light is .4 to .7 microns.
So, if a 6 Micron pixel has a lower limit of ISO = 50, a 2 micron pixel, with 1/9th the area, might give you ISO 15 and the best res per area (and consequently the best DOF for the res).
In a very small pixel there is very little room for data storage, so the max ISO of a 2 micron pixel would make it unmarketable in this high-ISO mad world.
Dick,
If I understand correctly (I'm useless in maths and enginering) and resuming in practical: to acheive a 35mm film pan quality print we need now in digital nothing less than an MF ?
oh oh...if that is true, this would feed the debate about digi-film and 35mm vs MFD...
Fred.
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Dick,
If I understand correctly (I'm useless in maths and enginering) and resuming in practical: to acheive a 35mm film pan quality print we need now in digital nothing less than an MF ?
oh oh...if that is true, this would feed the debate about digi-film and 35mm vs MFD...
Fred.
You asked about "Pan film", and did not specify that you were talking about "35mm Pan film".
When I gave up my film Nikon and moved to 120 film, initially I used 200/400asa film, but the results were not as good as Pan F 35mm, so I used pan F 120.
If 10 times the film size was the limit for enlarging from film, and if (for res better than the eye can see and less noise than the eye can see) you want no fewer than 360 pixels per print inch for enlarging from digital, then the best (60 Mpx) 645 MF digital is equivalent to 645 film.
35mm film would not be as equivalent to ff 35mm digital, because of the AA filters on DSLRs,,, but, if anyone ever made a quality ff 35mm camera, there is no reason why it should not be as good as 35mm film.
It depends which film you are comparing to which digital, and which yardstick you use (e.g resolution or noise).
If noise is your yardstick, Nikon is, I believe, a great deal better than Canon, and Hasselblad is a great deal better than Phase.
When you notice that a 2MPx 1080i TV screen looks as good as a 24 Mpx DSLR picture, it becomes apparent that it is not all about pixel count.
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I was talking about low iso Pan films from 40 to down.
35mm gigabitfilm can resolve more than 400 PImm according to the french shops in Beaumarchais.
a link here:http://forum.getdpi.com/forum/showthread.php?t=7817
Fred.
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There is more to ISO than that. ...
In the digital pipeline, the ISO adjustment controls the gain of an amplifier that works after the sensor captures light. Aperture and shutter control the amount of light (photons) that hit the sensor. ISO comes next, and controls the amplification of the analog signal obtained, and this amplification has very important consequences both in the signal to noise ratio and highlights headroom.
Your diagram fits my description, except that you then declare that only when the the signal level is adjusted in the analog domain is it "true ISO", while later adjustment of the digitized signal (multiplying the output numbers by an appropriate constant), is "fake". I am sorry, buy I do not accept that wording, given that the results either way are similar (though not identical) and I do not see that analog gain is unequivocally superior to later digital adjustment, so the use of adjectives "real" and "fake" seems prejudicial. Can you cite an official definition of "ISO speed" (from an ISO document, I suppose) to support this "fake" claim? To repeat, the only relevant definition I know of is an ISO definition of units of measurement of exposure index, which cover digital adjustments too.
I still see the strong possibility imagine that the best way to adjust exposure index while minimizing noise from the analog processing pipeline is to have fixed analog gain (as in a good power amplifier?) and an ADC of sufficiently large DR to cover from signal strengths from below the photosite noise floor to the full well signal strength, and then adjust the digital signal to the desired output level placement.
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Smaller pixels give you higher res (per unit area) and lower ISO (as they sense fewer photons).
smaller maximum ISO speed before noise is unacceptable (to 100% pixel peeping at least!), but no change in minimum ISO speed, which seems to be the main topic of this thread.
The smallest practicable pixel (pitch) is about 2 microns, as the wavelength of light is .4 to .7 microns.
A dubious claim since the vast majority of sensors made these days have photosite spacing of less than 2 microns, and some are as small as 1.2 microns. It is not entirely clear than even the wavelength of light is an absolute minimum limit: antennas can be considerably shorter than the wavelength of the signal they receive. For example, AM wavelengths are about 200 to 400m, but most AM radios are smaller than that!
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Your diagram fits my description, except that you then declare that only when the the signal level is adjusted in the analog domain is it "true ISO", while later adjustment of the digitized signal (multiplying the output numbers by an appropriate constant), is "fake". I am sorry, buy I do not accept that wording, given that the results either way are similar (though not identical) and I do not see that analog gain is unequivocally superior to later digital adjustment
If you think true and fake ISO yield similar results just look at the images on the left (shot at ISO100, numbers multiplied by an appropiate constant) vs the images on the right (shot at ISO1600), both at the same aperture/shutter (i.e. identical amount of light hitting the sensor in both cases):
(http://www.guillermoluijk.com/article/iso/versus.jpg)
(http://www.guillermoluijk.com/article/iso/bodegon.jpg)
The thick red curve in the following SNR vs RAW exposure plot shows SNR improvement when raising (true) ISO for a given aperture/shutter pair. In the deep shadows on a Canon sensor, SNR almost doubles (+6dB means doubling SNR) from ISO100 to ISO200, being the improvement less noticeable the higher the ISO setting. Going beyond ISO1600 doesn't produce any improvement, no matter if ISO3200 and above are true ISOs.
(http://www.guillermoluijk.com/article/isos5dmkii/snr5dmkii.gif)
The 'true' or 'fake' ISO wording is just irrelevant semantics. The important thing to know is that there _is_ a difference between analog gain ISO and software ISO in order to get the best from our cameras.
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I already agreed that there is some difference, what I am debating partly is the prejudicial use of "real" and "fake" for the two alternatives. Do not pretend that the word choice is arbitrary: "fake" has an obvious derogatory meaning! Would you mind if someone started using "real" only for digital amplification and "fake" for ISO adjustments done with analog gain? People have indeed claimed that analog gain is a fake change in ISO speed, and that only base ISO is a real ISO!
Your extreme example seems to consist of exposing at exposure index 1600 but using analog amplification to four stops less (ISO 100 setting), so pushing the analog signal strength down so low that it then suffers horribly from noise later in the processing pipeline, including probably quantization noise from the ADC. Which only shows that a fixed analog gain approach would probably use far higher than "ISO 100 level" with that sensor. Maybe closer to its "film equivalent (noise based) ISO speed", which is probably about 800 to 1600.
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I already agreed that there is some difference, what I am debating partly is the prejudicial use of "real" and "fake" for the two alternatives.
There is not some difference, there is a big difference as seen in the examples above. I understand your point about the wording, but I don't consider the discusion about semantics too interesting, sorry. You are free to propose new names for the 'real' and 'fake' ISOs.
Your extreme example.
The example is not extreme at all. It is a part of an article explaining that in low light conditions (a very common situation), pushing camera ISO is very convenient vs digital amplification.
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I didn't get this image:
(http://www.guillermoluijk.com/article/iso/modelo.gif)
If Npost symbolizes the digital amplification (aka fake ISO) then it should be placed after the A/D converter.
I agree that fake and real iso is a little misleading though. Real iso is not real anyway because the sensitivity of the sensor is not changed, only the amplification in the analog stage. Fake iso is definitely fake though because it's just a multiplication of raw values, an amplification in the digital domain. For a raw shooter there is no point in using fake iso settings because it will only cut headroom in the raw file without any benefits. The same result can be obtained by increasing EV in the raw converter but without the side effects. However for jpeg shooters it's needed because the images would look underexposed otherwise.
Maybe we should just call it analog gain and digital gain and be done with it. They use the terminology gain in video don't they? Gain is certainly used in the audio field and digital audio has been around longer than digital imaging.
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If Npost symbolizes the digital amplification (aka fake ISO) then it should be placed after the A/D converter.
No, it symbolyzes (analog) noise introduced after the ISO amplification stage, i.e. at any point of the A/D conversion before the digital encoding process took place.
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No, it symbolyzes (analog) noise introduced after the ISO amplification stage, i.e. at any point of the A/D conversion before the digital encoding process took place.
Thanks, that makes sense - N for noise introduced at that stage.
So adding to your original drawing it would look something like below if we add the additional digital ISO as well:
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I seem to recall seeing photos, such as those of space shuttle launches, where the ISO of the film used was 25. No, that's not a mistake, ISO 25. Why? Because the takeoff is a very very bright event, when you're close up. But doesn't a really fast shutter make up for that? In this case, yes, but not all...
Recently I was sitting on the rocks of a stream, during daylight hours, trying to get the "smooth water" effect. But even at ISO 100, using a high grade polarising lens, it's just too bright. With a bit of research, it seems that the trick these days is to use a rather dark filter. This cost of this approach is a(nother) bit of glass in front of the lens, potentially having a negative impact on your image quality (think of Reichman's notes about how the UV/haze filter of today really doesn't add any value and that it's like shooting through a window.)
Of course, the f-stop can be reduced down to, say, f/22 or smaller, but this too can have an impact on image quality due to diffraction and airy discs.
This all got me thinking and wondering if in the pursuit of high ISO perfection in low light, we're hurting ourselves at the other end and we just haven't realised this. For instance, various DSLRs now have a minimum ISO of 200. Those "smooth water" shorts are now going to require more effort than before this.
Of course ISO 25 is not going to be of benefit to those great big white lens folks that walk around sporting events nor the paparazi flooding a star with flashes at an interview. Nor is it going to help parents at their children's party or sporting event on the weekend. But now that the "film" is part of the camera body, for those that became used to low ISO with landscape photography, it seems like that choice has been removed. And whilst some cameras today are sold with ISO 50 capability, analysis seems to suggest that this is just a corrected, underexposed photo at ISO 100.
Comments?
Hi,
Your post sure sparked replies advocating digital... at high (base?) iso. What they did not mention was that a higher iso also mean a more contrasty photo (lower quality digital capture, not to mention higher noise). Sure, advancement in digital techniques have led to better and better sensors, albeit some folks for optimum quality at least in certain circumstances still shoot FILM (slide or BW). I shoot MFDB with base ISO 50, and yes there is also no AA over sensor to degrade the image. You are correct, ANY filter over lens will also degrade quality, while indeed a lower ISO result in better image quality (as in for digital the base ISO, not extended). Some pros still use the 25 ISO in Leaf Aptus 22 MFDB, why? I also shoot film, and yes... exclusively Velvia rated at 50 ISO. Why? Clean files, and best image quality for landscapes in certain circumstances. At most I shoot 400 ISO and those times on my MFDB (but for landscapes no higher than 100 ISO). For quality images I do not see that one need more. Now... if we speak of sports or news photography where point is to nail a shot in dim light or of quick action just to sell, and thus with no more image quality than can be printed on web or in a newspaper... then it really does not matter of image quality beyond that requirement. Or... if point frank is to simply sell more new cameras that makes people upgrade and spend $$ every other year, thus making people believe that high ISO is the best thing since sliced bread can perhaps help... (!)??? Though from my eye, you are right. Low ISO still yields best image quality, but a tad forgotten among all else. Look around at big advertisement prints... many not even sharp. Why?
I am sure there will be posts arguing opposites to my above comments... but I frank write what I humbly see.
Attached, one shot digital, one shot film. I believe most can tell which is which. Digital tends to appear as to record color, while a quality slide film tend to record light (and with a magic interpretation of it). And yes, the attached are low ISO. For portrait I prefer digital hands down, for landscape, I am split. For blurring water... of course clearly LOWest iso (= 50).
Regards
Anders
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The reason to distinguish Npre and Npost was just to put into straightforward equations the explanation of why output SNR improves when pushing ISO that Emil Martinec pointed somewhere.
The total signal output from the ideal ISO amplifier is:
Samp = (S + Npre) * Giso
The total signal output from the ideal ADC is then:
Sad = (S + Npre) * Giso + Npost
The SNR ouput from the ADC stage would then be:
SNR = (S * Giso) / (Npre * Giso + Npost)
When pushing ISO (higher ISO gain, Giso), Npost becomes << Npre * Giso, so the SNR maximises to the limit:
SNRmax = S / Npre
Cameras where the Npost effect is higher than Npre (Canons) benefit more from pushing ISO. In cameras where Npre is higher than Npost (Nikons) the convenience of pushing ISO in low light conditions is not so critical.
Regards
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Digital tends to appear as to record color, while a quality slide film tend to record light (and with a magic interpretation of it).
That's so funny ... I was just saying to my wife that I thought film tends to appear as to record color, whereas a quality digital capture tends to record light (and with a magic interpretation of it.)
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...yes, but, if you want a nice smooth pictures without banding, you need the pixels for the darker parts of the picture to be capturing a minimum 20 or so photons each, and the light parts 2^8 to 2^16 times as many photons.
If you do not have a very large number of shades of each colour you get banding.
When you are trying to stretch the ISO, and one pixel (photon bucket) in a hundred captures a photon, and you amplify the signal until your photon buckets overflow (blown-out highlights or clipping), I assume you try to get clever software to transfer the overflow to adjacent pixels, which tends to result in digital grain, or noise, or Canon balls or Phase lumpiness or whatever you want to call it.
I am (OK "has been") many things.. including a qualified and experienced electronic engineer and real-time programmer.
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That's so funny ... I was just saying to my wife that I thought film tends to appear as to record color, whereas a quality digital capture tends to record light (and with a magic interpretation of it.)
You may wish to revisit your sunset gallery. Contrary to a quality slide film it come across to my eye to render color but not much of light.
Above is my humble and honest impression. The obvious should be that it is not by obsession for gear that I amuse to carry multiple cameras with lenses - film and digital - around not only to the field but on travels. I much would prefer one camera, however I see that both digital and film excels for different things. What I pointed out in above of color vs. light was a point made of the way digital tend to render with emphasis on color but not of light. I guess it is simply how film is tuned in comparison and how the silver particles in it add sparkles in magic ways which yet is not achieved for digital. Sure it is ok to have differing view, but also to be suffice educated for the fact that while for sure digital excels at some things and film excels at some, they are simply different medias. For landscapes... low ISO excels and seem much forgotten by Nikon, Canon and the likes. They wish to sell more cameras simply. A capture of a waterfall at 200ISO and a neutral density filter is hardly the optimum for image quality, just a way around the sensors that are not tuned for that kind of purpose.
I shot Nikon before; F100 and Velvia 50. Great camera, and great film, albeit I now feel was small format. Last Nikon I had was D200 at the time it was raved about being superior to film and of such very magic greats. Frankly my eye failed to be seduced by the technology and failed to see superiority to film. In fact I experienced its color rendering and brilliance of light to be crap compared to Velvia. Nikon has significantly improved with D700/D3/D3X, but they still do not reach MFDB, and those not near film in some of renderings: namely light.
Regards
Anders
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...
Please define the following terms if you would like to have a conversation that is meaningful to anyone other than yourself:
*** Light
*** Color
*** Magic
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Frankly my eye failed to be seduced by the technology and failed to see superiority to film. In fact I experienced its color rendering and brilliance of light to be crap compared to Velvia. Nikon has significantly improved with D700/D3/D3X, but they still do not reach MFDB, and those not near film in some of renderings: namely light.
Regards
Anders
Man serious 10 * 8 landscape photographer are now turning to MF, and I believe that something like...
Apo-digitars
Sinar P3
Hasselblad H4D-60
...is fully up to matching Velvia, and will soon be the tool of choice for Landscape photographers not very limited re budget.
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smaller maximum ISO speed before noise is unacceptable (to 100% pixel peeping at least!), but no change in minimum ISO speed, which seems to be the main topic of this thread.
A dubious claim since the vast majority of sensors made these days have photosite spacing of less than 2 microns, and some are as small as 1.2 microns. It is not entirely clear than even the wavelength of light is an absolute minimum limit: antennas can be considerably shorter than the wavelength of the signal they receive. For example, AM wavelengths are about 200 to 400m, but most AM radios are smaller than that!
You are correct about small antennas. But small antennas are not very good at collecting incoming radiation. The larger the better. With light photons you can still have small apertures but the output direction or even the color of the light now becomes questionable. The CFA performance will start to really suffer if the photodetector pitch is less than a wavelength. Perhaps ejmatin can put some real numbers to this.
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The CFA performance will start to really suffer if the photodetector pitch is less than a wavelength. Perhaps ejmatin can put some real numbers to this.
I was thinking that as the pixel pitch gets less than about three times the wavelength of the incident light, there would be little increase in the resolution of the camera system... no need for AA filters as a high proportion of the light will be spread over more than one pixel... but it depends on the size of the sensitive area of the pixel relative to the pixel pitch.
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Man serious 10 * 8 landscape photographer are now turning to MF, and I believe that something like...
Apo-digitars
Sinar P3
Hasselblad H4D-60
...is fully up to matching Velvia, and will soon be the tool of choice for Landscape photographers not very limited re budget.
Ehh. Regardless that does not mean that a P65 have details of 8x10 (albeit on this very site it was years ago claimed a 6MP camera was about equal to 35 film, nonsense). More so it is difficult to achieve the rendering of Velvia using a MFDB or any digital, simply they are different medias. That said MFDB excels over smaller digital. The difficulty in gaining pleasing rendering of light with digital is in particular at the for landscapes most magic minutes of low sun and sunrise/sunset.
One very successful landscape photographer who have turned towards also use digital is Peter Lik. In his online videos he has quick gone through DSLR -> Hassy -> Mamiya 645 / Phase One -> P45 on Alpa. Yet... the rendering still appear different from these than his 617 Velvia 50. Make a search on Youtube 'Peter Lik'. He is arguably at the very top end, perhaps in $$ earnings the most successful landscape shooter ever. It appears he still keeps using his old Linhof 617 mated with Velvia @ ISO 50 alongside digital. One must ask why?
Now if you want to argue digital beats film, that is rather childish and outside the point I made. I shoot both, and I prefer digital for certain applications, and am very very please with my Leaf Aptus and the colors it records, albeit not Velvia. Still slide film simply excels at others. In many landscape applications slide film is a lot easier than digital, the main problem is the scarcity of labs.
Albeit, this is a site where many advocate DIGITAL. Some nice film images can be found among posts here http://www.largeformatphotography.info/for...isplay.php?f=30 (http://www.largeformatphotography.info/forum/forumdisplay.php?f=30)
One post above asked me to quantify light, color etc. I decline, because if you cannot see it with eye, then what is point? Photography is artistic and visual arts.
Regards
Anders
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Peter Lik -- Here is one; http://www.youtube.com/watch?v=moutL1dHaTY...feature=related (http://www.youtube.com/watch?v=moutL1dHaTY&feature=related)
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Ehh. Regardless that does not mean that a P65 have details of 8x10
I think 645 digital is equivalent to 645 film.
More so it is difficult to achieve the rendering of Velvia using a MFDB or any digital, simply they are different medias.
I like to look at the picture (not the media) and see the original subject through the picture like it was an open window. (Peter Lik said something similar on one of the videos) Oil and watercolour are different medias... and some people like to see brush strokes or film grain in pictures as anything pre-digital can appeal to traditionalists.
One very successful landscape photographer who have turned towards also use digital is Peter Lik. In his online videos he has quick gone through DSLR -> Hassy -> Mamiya 645 / Phase One -> P45 on Alpa. Yet... the rendering still appear different from these than his 617 Velvia 50. ... It appears he still keeps using his old Linhof 617 mated with Velvia @ ISO 50 alongside digital. One must ask why?
It seems that he uses the 617 for panoramic format, and the digital for everything else. If he thought res was the limitation he would use 10 * 8. If he thought that digital was not as good as Velvia, he would not use digital. For panoramic I intend to use 3 * 645 with a triple stitch back
In many landscape applications slide film is a lot easier than digital, the main problem is the scarcity of labs.
In what landscape applications is film easier than digital, and why? Any fool can use digital, so how can you argue that film is easier?
The way I see it, you get more DR and more control with digital, (like being able to develop the film, do a trial print, and them go back and give the film more development to bring out shadow detail).
...and if Latitude was the limitation, you would use colour negative film rather than transparencies.
...and you get instant feedback so you can go home knowing that you have got the shot.
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One post above asked me to quantify light, color etc. I decline, because if you cannot see it with eye, then what is point? Photography is artistic and visual arts.
Guy ... you are the one making the post on a forum message board ...
If you are gonna invent words for which only you know the meaning, you can talk until you are blue in the face and nobody will ever have a clue what you are saying.
Good luck with your magic.
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Nikon has significantly improved with D700/D3/D3X, but they still do not reach MFDB, and those not near film in some of renderings: namely light.
Anders,
Have you used a d3x since we last discussed this? At that time you had not if my memory serves me well.
(http://farm5.static.flickr.com/4038/4378383575_e692c406a1_o.jpg)
Cheers,
Bernard
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Hi,
I would say that there are significant differences between digital and film.
1) Digital sensors are nearly linear devices, when they saturate they essentially "clip", film has toe and shoulder characteristics and avoids clipping, essentially by compressing highlights and shadows.
2) Negative film has a lot of latitude for overexposure
3) Color film is subtractive while digital is additive
4) Color films (like Velvia) have very special tonal and color characteristics. Digital applies color mostly in post processing (it's called profiles, color matrix, etc)
Some additional differences:
- In general digital sensors have much less noise than film (at comparable ISO)
- Digital sensors are limited by sensor resolution while resolution on film drops gradually
- Film has a significant thickness
In my view the undisputed advantage of film is in handling extreme highlight. Other than that digital is preferable to film in my opinion.
Best regards
Erik
I think 645 digital is equivalent to 645 film.
I like to look at the picture (not the media) and see the original subject through the picture like it was an open window. (Peter Lik said something similar on one of the videos) Oil and watercolour are different medias... and some people like to see brush strokes or film grain in pictures as anything pre-digital can appeal to traditionalists.
It seems that he uses the 617 for panoramic format, and the digital for everything else. If he thought res was the limitation he would use 10 * 8. If he thought that digital was not as good as Velvia, he would not use digital. For panoramic I intend to use 3 * 645 with a triple stitch back
In what landscape applications is film easier than digital, and why? Any fool can use digital, so how can you argue that film is easier?
The way I see it, you get more DR and more control with digital, (like being able to develop the film, do a trial print, and them go back and give the film more development to bring out shadow detail).
...and if Latitude was the limitation, you would use colour negative film rather than transparencies.
...and you get instant feedback so you can go home knowing that you have got the shot.
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Anders,
Have you used a d3x since we last discussed this? At that time you had not if my memory serves me well.
Cheers,
Bernard
Bernard,
Nope I have not. I think it too is simply a tool, just like any of my cameras are or any of the other posters'. I seen images, tried raws out of curiosity and read what others using it and MFDB says. I do respect you like your D3X and that you like rotational stitching. And no, I see no point in trying out D3x, why? It is destined to bring me less than my 28MP MFDB brings on all counts. Besides... I like medium format and up and not DSLR. The sensor in D3x is smaller and less capable than my MFDB (low ISO). And as I respect that you have a different preference, I hope that you are able to see respect as such both ways. You found what you experience as good tool in D3x, I in mine, others in theirs. I simply prefer using the two tools I experience as good; Leaf Aptus and slide film.
B.t.w. I read your write up of Pentax 645. Any consideration of stepping back to medium format digital again, or you prefer Nikon?
To all,
Not against anyone or anyones opinion, but too many of the posts above appear to come across as replying with quotes from mine to seemingly argue (e.g. a few words tossed without substance) against what I clear expressed as my view and observation, or did I misunderstand? It feels tad like one have to be careful on LL to whisper the word FILM or people jump at you and argue of digital. I shoot and like both. It is ok to have different opinion and likes and to express them. Also on likes of Peter Lik and his art and tools. I thought that referring to him would make a tad clear, simply there are different tools for different purposes; such as film and digital, and low ISO and higher. Seem odd if Peter Lik stuck to film for the 3:1 proportions of 617 when that can be stitched with digital also, even round stitch as he also done. Digital and film simply render different. However, when come to light I pointed out and gave two example photos that to my eye clear seem to highlight that example. Peter Lik is a good example, because he is a shooter of trancient light and color.
Yes, in detail I find my 28MP MFDB about similar to 6x7 (because 22MP ZD was short of it), but... in rendering the MFDB is complete different. For "sweet light" I find slide film often render superior of lights in landscape, as I showed in my example photos.
The thing that is not ok and very impolite is when someone argue of that mine is better than yours, and stick it out that "no digital eats film". That is plain silly, for digital is still learning.
Thank you! Now lets move on... Subject was low ISO? Any other users of 50 ISO here?
Regards
Anders
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B.t.w. I read your write up of Pentax 645. Any consideration of stepping back to medium format digital again, or you prefer Nikon?
Not too sure yet. My choice in favor of the D3x is based on an objective assessment of its value as a tool for my applications. I do not like or dislike MF. I did shoot MF quite a bit in the past with both Hassy H1 film and Mamiya digital.
Following my 1+ year ownership of a Mamiya ZD, the 645D is the first medium format digital camera I could see myself buying thanks to is ruggedness, cold weather battery life and reasonable pricing but...
- I would have to invest in lenses as well (although a 120mm f4 macro would cover 95% of my stitching needs),
- the value relative to the D3x for stitching will be pretty little as there are not that many more pixels on the long end due to the 4:3 aspect ratio vs 3:2,
- the lack of live view is also an issue for me as well since I like my images to be focused on the very subject and not a bit in front or behind. I have gotten really used to seeing 99% of tack sharp images when viewed at 100% on screen and going back to lower success ratio is a depressing thought,
- the lack of T/S lenses also means a lot more DoF stacking which is often difficult to perform in cold weather conditions,
- there will probably be no RRS plate for the 645D until it is sold in the US which is a problem as well,
- the 645D is a camera that is a lot more specialized than the D3x and I would therefore have to keep both which isn't too reasonable from an economic standpoint.
So all in all, I have not taken a firm decision yet, but the probability I buy the 645D is fairly low.
Cheers,
Bernard
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Hi,
Will you have an opportunity to evaluate the Pentax 645?
As things are now there is a lot of talk but I have seen very little evidence. Myself, I don't really see myself going for the P645, except if it can use my Pentax 67 lenses. I would expect a 645 camera to have something like a one and half stop advantage, all other parameter being the same. It's quite obvious that the parameters are not the same. Your 3DX seems to have better IQ than my Alpha 900, although much of the sensor technology is shared, AFAIK.
My main interest is to understand the differences. Would be nice to have some good and comparable raw images from DSLR and MFDB.
Best regards
Erik
Not too sure yet. My choice in favor of the D3x is based on an objective assessment of its value as a tool for my applications. I do not like or dislike MF. I did shoot MF quite a bit in the past with both Hassy H1 film and Mamiya digital.
Following my 1+ year ownership of a Mamiya ZD, the 645D is the first medium format digital camera I could see myself buying thanks to is ruggedness, cold weather battery life and reasonable pricing but...
- I would have to invest in lenses as well (although a 120mm f4 macro would cover 95% of my stitching needs),
- the value relative to the D3x for stitching will be pretty little as there are not that many more pixels on the long end due to the 4:3 aspect ratio vs 3:2,
- the lack of live view is also an issue for me as well since I like my images to be focused on the very subject and not a bit in front or behind. I have gotten really used to seeing 99% of tack sharp images when viewed at 100% on screen and going back to lower success ratio is a depressing thought,
- the lack of T/S lenses also means a lot more DoF stacking which is often difficult to perform in cold weather conditions,
- there will probably be no RRS plate for the 645D until it is sold in the US which is a problem as well,
- the 645D is a camera that is a lot more specialized than the D3x and I would therefore have to keep both which isn't too reasonable from an economic standpoint.
So all in all, I have not taken a firm decision yet, but the probability I buy the 645D is fairly low.
Cheers,
Bernard
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Will you have an opportunity to evaluate the Pentax 645?
Erik,
I don't know. I don't have any particular relationship with Pentax.
It would be fun to run it against the D3x, but either way we know that people will read whatever they want in the results...
Cheers,
Bernard
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Bernard,
Yes, whatever you do you always get a lot of "flak".
Best regards
Erik
Erik,
I don't know. I don't have any particular relationship with Pentax.
It would be fun to run it against the D3x, but either way we know that people will read whatever they want in the results...
Cheers,
Bernard
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Not too sure yet. My choice in favor of the D3x is based on an objective assessment of its value as a tool for my applications. I do not like or dislike MF. I did shoot MF quite a bit in the past with both Hassy H1 film and Mamiya digital.
Following my 1+ year ownership of a Mamiya ZD, the 645D is the first medium format digital camera I could see myself buying thanks to is ruggedness, cold weather battery life and reasonable pricing but...
- I would have to invest in lenses as well (although a 120mm f4 macro would cover 95% of my stitching needs),
- the value relative to the D3x for stitching will be pretty little as there are not that many more pixels on the long end due to the 4:3 aspect ratio vs 3:2,
- the lack of live view is also an issue for me as well since I like my images to be focused on the very subject and not a bit in front or behind. I have gotten really used to seeing 99% of tack sharp images when viewed at 100% on screen and going back to lower success ratio is a depressing thought,
- the lack of T/S lenses also means a lot more DoF stacking which is often difficult to perform in cold weather conditions,
- there will probably be no RRS plate for the 645D until it is sold in the US which is a problem as well,
- the 645D is a camera that is a lot more specialized than the D3x and I would therefore have to keep both which isn't too reasonable from an economic standpoint.
So all in all, I have not taken a firm decision yet, but the probability I buy the 645D is fairly low.
Cheers,
Bernard
Bernard,
I am not trying tempt you over the fence, if there at all is one. However I could advise of the AFD III camera as already being rather plenty. The DF also here in Asia is much more $$, heavens knows why. It might be a tad faster at AF, but also an old AFD already works to capture images. Any of these not near as fast AF as Nikon. Reading your thoughts, the old 120mm is cheap on Ebay, and just as sharp as the brand new, the downside is stopped down metering. There is the Mamiya 50mm shift lens to buy used as well, also that is reportedly very sharp. Hartblei are hard to come by, and unsure if one catch a quality optic copy. This said, not at all as many tilt shifts as for Nikon and of course a smaller sensor give more DOF. For tilts one could go with large format lenses on a technical camera, such as Sinar arTec, but... then very sharp lenses but very $ camera + large format shooting style.
Actually, for my own use I have not found tilts critical. Rather, I experience some controlled out of focus to lend pleasant rendering but that is personal. One wish would be if they made a more affordable small tech camera with rise or shift. There is none. Perhaps I should trade for a Mamiya 50mm shift. The reflection I made when I stepped to Mamiya from Nikon was that you can buy parts of the lenses for less than Nikon, and with no extra weight in bag.
Fingers crossed for Pentax that they pull their 645 digital off tuned right to deliver very high quality images, and also send it out to the world market.
Regards
Anders
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My main interest is to understand the differences. Would be nice to have some good and comparable raw images from DSLR and MFDB.
Erik,
You can download from Leaf here http://www.leaf-photography.com/rawimages.asp (http://www.leaf-photography.com/rawimages.asp)
Regards
Anders
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I don't think there was ever going to be a 'visual revolution' with a few stops of improvement in high iso performance and no on promised one. You could shoot film at 6400 just like you can shoot a dslr at 6400 but what is does mean is that pictures that were once taken in these situations with loads of noise and fell apart at anything over 6x4" can now look very good printed to make larger sizes which is great for both photographers and clients.
Ask any good wedding photographer what high iso has done for them during church ceremonies where no flash is allowed.
Wholeheatedly agree. What used to matter with film at 25-50 ISO is pretty irrelevant now. 200 ISO is amazing. But more importantly, as a wedding photographer and a natural light photographer when it comes to children and babies, the low light wonders of my D700 (let alone the D3s) are an absolute miracle.
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Hi Bernard,
What do you mean ISO 6 ??
Is that Kodak really a good camera? it has been hardly critisized everywhere.
Fred.
Well for the spray and pray, take it out of the box and just use it crowd, it sucks. If you have plenty of light, understand how to get the best out of a camera and are willing to learn it's foibles, it can be a wondrous sight to behold. Look at it crosseyed and it'll bite you in the ass. I love mine, but always have a backup plan.
erie
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Your 3DX seems to have better IQ than my Alpha 900, although much of the sensor technology is shared, AFAIK.
Best regards
Erik
The D3x's 14bits and CFA create much of the difference between the two cameras. The D3x can certainly coax more shadow detail when boosting shadows, due to it's 14 bits (however the 14 bits are achieved,) and so it has a DR advantage over the A900. The A900 has better color separation/hue resolution in the greens than any current Nikon camera, because of the CFA choice. The cost of the better color separation of the Sony's CFA is that it blocks more light to the sensor than the Nikon's CFA, so more amplification is required at a given exposure. That is why the D3x has a bit better noise performance in low light.
It's really not a matter of better than. For landscape shooting, it's a matter of better shadow detail vs. better detail in things like foliage. The ideal landscape 35mm combination would probably be the 14bit D3x sensor with the A900's color filter.
p.s. from what I understand, the Sony CFA also makes the camera less friendly with some converters due to how the converters implement WB, causing blotchiness and poor detail. RPP has been a revelation in detail for my A900 files.
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sorry, duplicate post.
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Hi,
I don't argue with your statement.
To me it seems that the processing pipeline in ACR and Lightroom 3 Beta 2 really improve high ISO performance on my Sony Alphas, at least in some cases.
Best regards
Erik
The D3x's 14bits and CFA create much of the difference between the two cameras. The D3x can certainly coax more shadow detail when boosting shadows, due to it's 14 bits (however the 14 bits are achieved,) and so it has a DR advantage over the A900. The A900 has better color separation/hue resolution in the greens than any current Nikon camera, because of the CFA choice. The cost of the better color separation of the Sony's CFA is that it blocks more light to the sensor than the Nikon's CFA, so more amplification is required at a given exposure. That is why the D3x has a bit better noise performance in low light.
It's really not a matter of better than. For landscape shooting, it's a matter of better shadow detail vs. better detail in things like foliage. The ideal landscape 35mm combination would probably be the 14bit D3x sensor with the A900's color filter.
p.s. from what I understand, the Sony CFA also makes the camera less friendly with some converters due to how the converters implement WB, causing blotchiness and poor detail. RPP has been a revelation in detail for my A900 files.
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Hi,
I don't argue with your statement.
To me it seems that the processing pipeline in ACR and Lightroom 3 Beta 2 really improve high ISO performance on my Sony Alphas, at least in some cases.
Best regards
Erik
I agree. LR3 beta 2 is a GIANT leap forward for A900 files compared to LR2. However, as much as I want to stick with the ease of an all LR3 workflow, I've begun experimenting again with converting RAW in RPP and sending the TIFFs to PS or Lightroom, and you just can't beat the raw conversion quality of RPP, IMO. The slow, methodical application of adjustments in RPP really makes a difference. The NR of LR3 still works well on TIFFS, as far as I can tell.