Luminous Landscape Forum
Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: fredjeang on November 12, 2010, 05:22:48 am
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I found a Burtynsky interview where he was explaining that the digital backs are going to pass the 100MP barrier ( 120 MP ) and when that will happen it will overcome the current large format film resolution.
So if I understand Burtynsky well, the current digital backs are still not capable of surpassing the 8x10 films resolution until they will reach 120MP. But it seems that his affirmation is contradicting the "datas that are disponible" in internet.
It would be nice if large format film users who also work with high end backs could comment on that matter.
Is the Burtynsky statement correct?
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Fred,
there has been the thread about this not a long time ago. If you have ever worked with bigger sizes like 8x10 you will know there is something beyond the mere resolution which IMO has reached a more than enough level for all sort of things at least we do. Although I really love and enjoy working with digital backs and would never think of going back for a second, the DOF rendering of the larger formats is something that could feel lacking.
Cheers, Ulf
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Burtynsky output are art galleries. I got the feeling for what I've been talking so far with gallerists, that there is a sort of snobery about using big films. For big prints, each time i asked about digital or film the gallery attendant had always this kind of answer. "film of course!"...
The thing is, is it really snobery, or films are still giving a more "noble" imagery? (independently of the hassles compared to the digital workflow)
Seems that in the big galleries, there is still a sort of resistence or suspiciouscy about the digital imagery for fine arts, but this is changing.
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The conclusion of the thread Ulf has mentioned was that a well exposed, focused and developed 8 x 10 is far beyond the capabilities of current backs. The problem is that getting a perfect 8 x 10 image is pretty much impossible / very very hard. Maybe 120 mp would change it, but who knows- we'll have another discussion regarding 8x10 vs 120 mp at that time :)
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hmm...
you could also argue you can only listen to music that is reproduced by high end turntables, vinly records, amplified with tube amps...I am sure you will find a lot of guys that will second that. ;D
I do not believe this gallerist will be able to tell whats done with film and whats done with digital.
Cheers, Ulf
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It seems that the "vintage label" or traditional technics is a sale argument for them. I'm not sure it can be clearly recognisable. I think most of the people could not make any difference.
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Its not all about resolution. LF film or MF film photography has a different "taste" or "haptics" which has nothing to do with snobery IMHO, but with image parameters, which are not only mere resolution. Especially the rendering of out of focus or slight out of focus areas and the transition between sharp and OOF areas is different. I do not have scientific data at hand, its just from images I saw, and some talking I had with others - professionals- using film. Because of that different characteristics, especially of the OOF areas I decided to sell my Mamiya Press in the future and move to an Arca Swiss 4x5" and not to some digital thing in the first step. The digital workflow, speed and overall handling together with the quality of their images make modern digital cameras incredible, great tools, but MF or LF film is something different. Maybe in the future this will change - with bigger sensors and sensors without Lowpass filter, but for now there are still differences in aesthetics which matter.
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The conclusion of the thread Ulf has mentioned was that a well exposed, focused and developed 8 x 10 is far beyond the capabilities of current backs. The problem is that getting a perfect 8 x 10 image is pretty much impossible / very very hard. Maybe 120 mp would change it, but who knows- we'll have another discussion regarding 8x10 vs 120 mp at that time :)
I was not aware of this beeing the only conlusion of the other thread, what I meant was kind of the opposite like Christoph adresses. The out of focus / depth of field rendering -regardless of the overall resolution- is different and that is what I am missing sometimes, wish it could be done digital. But this cannot be achieved, it is a matter of input size and I am not expecting a full frame LF sensor. We did a designer´s portrait with 8x10 polaroid some years ago, it was printed extremely small and still had the magic LF touch that only can be created by a huge film size, suppose resolutionwise 6MP would have been enough.
Cheers, Ulf
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I was not aware of this beeing the only conlusion of the other thread, what I meant was kind of the opposite like Christoph adresses. The out of focus / depth of field rendering -regardless of the overall resolution- is different and that is what I am missing sometimes, wish it could be done digital. But this cannot be achieved, it is a matter of input size and I am not expecting a full frame LF sensor. We did a designer´s portrait with 8x10 polaroid some years ago, it was printed extremely small and still had the magic LF touch that only can be created by a huge film size, suppose resolutionwise 6MP would have been enough.
Cheers, Ulf
I remember this when I was young, I had 6x9 plate cameras, and then someone donated a broken Leica; the Leica images were never as good as my contact prints from the plate camera.
Edmund
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I was not aware of this beeing the only conlusion of the other thread, what I meant was kind of the opposite like Christoph adresses.
Initially I thought we are speaking about the resolution alone. I wouldn't try to paraphrase the whole thread since obviously there is so much more into it- both in the thread and when it comes to 8x10 film and DB differences. Although I don't use film anymore, I still think there's a huge difference (in general, not only 8 x 10 vs db) in the feel, subjective aesthetics, organic sensation you get when you watch film output, and no craftsy workflows, PS filters and plugins will be able to make it up.
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Fred,
A singular analogue artifact (negatives) will always be worth more than the infinitely and instantly copied digital file (binary code), at least in the fine arts world. That is starting to change as gallerists and artists begin to seriously control the number of prints made.
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Burtynsky has used 4x5 film, not 8x10 recently from what I've read/heard.
these new backs provide an easier and lighter method of making hi-quality images, but IMO, a properly done 4x5 color neg or chrome will still look better.
but the digital's catching up, and damn quick too.
I still shoot film(8x10) because it renders things differently, and its cheaper in the long run, FOR ME. I'm a student btw...
-Dan
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Hi,
I'd suggest that there is a lot of snobbery involved. On the other hand there is another factor. Different optical systems have a specific signature. With digital we may have a tendency for perfection. Large format lenses were never perfect, if you look at MTF data for any of them they are just awful, but they may have some kind of character. Rodenstock Imagons come to mind.
So I'd suggest that it is snobbery and perception.
There is also an aspect of workmanship. Shooting a single sheet of film costing perhaps 50 USD (including processing) vs. shooting images with very little marginal costs.
Best regards
Erik
Burtynsky output are art galleries. I got the feeling for what I've been talking so far with gallerists, that there is a sort of snobery about using big films. For big prints, each time i asked about digital or film the gallery attendant had always this kind of answer. "film of course!"...
The thing is, is it really snobery, or films are still giving a more "noble" imagery? (independently of the hassles compared to the digital workflow)
Seems that in the big galleries, there is still a sort of resistence or suspiciouscy about the digital imagery for fine arts, but this is changing.
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Hi,
I'd suggest that there is a lot of snobbery involved. On the other hand there is another factor. Different optical systems have a specific signature. With digital we may have a tendency for perfection. Large format lenses were never perfect, if you look at MTF data for any of them they are just awful, but they may have some kind of character. Rodenstock Imagons come to mind.
So I'd suggest that it is snobbery and perception.
There is also an aspect of workmanship. Shooting a single sheet of film costing perhaps 50 USD (including processing) vs. shooting images with very little marginal costs.
Best regards
Erik
But Eric, that's the same old trap that has been sprung over in another long thread: measured statistics. These, generally, have very little to do with how well things work in life. I can remember many ads for whisky products where the quality was just mind-bendingly good... 4x5 and upwards! Don't you remember those pics in airport concourses?
Rob C
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Large format lenses were never perfect, if you look at MTF data for any of them they are just awful, but they may have some kind of character. Rodenstock Imagons come to mind.
That's not really fair. The Imagon is a soft focus lens, meant to give a fuzzy image by design. If you compare slr lenses to modern large format glass (apo-sironar-s), the large format glass is still significantly worse (largely because it has to cover eight to thirty two times the surface area of digital sensors), but I wouldn't call it "just awful."
Over a small image circle, the best large format lenses are decently sharp. Outside that circle, they get worse, but the larger surface area makes up for it and large format film with a good lens properly focused reliably holds more detail than even an image from a full-frame digital slr. I also find distortion and chromatic aberration to be reduced with large format lenses relative to what I see with digital, largely due to simpler lens designs. And color 4x5 costs about $5 a frame to shoot at most, not $50. (Scans put the cost way over the top, but if you're scanning every frame you shoot you're either really good or really indiscriminate.)
I'm not going to pretend that modern large format lenses are anywhere near as good as slr lenses over their entire image circle (though they are surprisingly very close in the center; the sironar-s is just slightly worse than the Hasselblad H lenses at 20lp/mm over the same sized image circle at f11) but saying they're all awful because the Imagon is soft is like saying "all digital slr lenses are bad because the lensbaby is soft." It's just not true--and there's a whole lot more you can get out of shooting large format than just "some character" imparted by bad lenses.
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So I actually went through the trouble of digging this up, a comparison between an undisputedly "very good" medium format lens (the latest 80mm f2.8 planar for 6x6) and the "just awful" apo-sironar-s. Looking at its mtf at f5.6 over a 40mm image circle, the sironar-s drops from just over 80% in the center to slightly under 70% at the edges at 20 cycles/mm. The planar drops from 85% to worse than 40% at the edges. So the planar is sharper in the center but much softer at the edges. At 10 cycles/mm the sironar-s falls from over 90% to over 85%; the planar from around 95% to around 65%. So while the planar is sharper at the edges at f5.6, the sironar-s is significantly sharper across the frame. On these terms alone (mtf charts, the very terms you cite), it's hardly an awful lens.
But for a variety of reasons, this is a bad comparison. A better comparison would be at proper working apertures (f5.6 for the planar; f11-f16 for the sironar-s) comparing twice the cycles/mm on the medium format lens to what the large format lens produces (to compensate for large format having four times the surface area). Rodenstock only provides mtf at f5.6 and f22 so the comparison has to be made at f22, at which point diffraction is already hurting the lens' ultimate resolving power. But the sironar-s must also be traced to an 85mm radius and the planar to only 40mm.
In this fairer comparison, the sironar-s drops from just under 85% to just under 80% mtf at 10lp/mm. The planar drops from 85% to worse than 40% at the corresponding 20lp/mm. The sironar-s drops from just under 70% mtf to around 55% mtf at 20lp/mm. The planar drops from just under 70% mtf to around 20% mtf at the corresponding 40lp/mm. In this fairer comparison, were the mtf of the sensor not an issue (which of course it is), the medium format lens might be a tiny bit sharper in the center, but the large format lens would be far sharper toward the edges of the frame. The superior proximity of saggital and meridional mtf on the sironar-s results in an impressive lack of chromatic abberation.
So, if by "having some character" you "being a little less sharp in the center but much, much sharper and better corrected in practice because the frame is so big," then you would be right. The best modern plasmats have tons of character. All this said, a 36X24mm crop from large format is usually considerably softer than a frame of the same film from 135, which is inevitably softer than a full frame dSLR. But that's cropping 1/16th of the frame. Look, I'd shoot on a 5DII instead if I had the money to afford the camera and some tilt/shift lenses--but large format is just really good.
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Thanks Policar for just digging that out.
As an addition I'd (again) like to point to these two famous Zeiss articles about MTF,
which make very clear, that the percentage on the MTF charts is far from being all,
and that the course of the curves plays an important role as well for the overall image impression.
To sum it up:
There are not only few cases, where the MTF curve might look better than on another lens and
the images still look considerably worse.
Links:
Zeiss Camera Lens News with MTF article part 1 (http://www.zeiss.com/C12567A8003B58B9/ContentsWWWIntern/6569B04E7E955A7AC125751A004AB773)
Zeiss Camera Lens News with MTF article part 2 (http://www.zeiss.com/C12567A8003B58B9/ContentsWWWIntern/FA89909F3030A628C125757E005A4755)
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I'm a bit surpised this is even an issue. Taking resolution alone, all things being equal then you need about 50-70mp to more or less match typical 4x5 LF film in my opinion. 8x10 has 4 times the area of 4x5, but its very difficult to get everything aligned correctly to make the most of it, so you are unlikely to need 200mp+ to get better results than 8x10 film. There are also far more variables with film, such as film flatness, lens choice, and of course scanner quality, than make comparisons more difficult. I still have an 8x10 LF camera kicking around but I have no intention of getting it and my old drum scanner out anytime soon. Also, its is not all about digital catching up with film. Digital MF does some things a lot better than film. I don't feel the need to make comparisons with film any more.
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Hi,
To begin with I'm sorry that my comment was more harsh than intended. What I essentially mean is that art buyers may look at other qualities than just technical merit. There may be some perception of greater value added by large format equipment.
That said, one very good reason to use large format is that film is cheap compared to sensors for a limited number of exposures. Excellent quality can be achieved by relatively affordable equipment while anything digital in excess of a full frame DSLR is coming at a fairly high price. For a pro shooting a large number of images film and processing costs would quickly go pretty high.
Looking at MTF curves I still have the opinion that LF-lenses are lacking in performance. They have essentially been intended for usage with film. A good example is the Schneider APO-Symmar 180 below. Note that curves on this lens correspond to 5, 10, and 20 lp/mm. For MFDBs and DSLRs normally 10, 20 and 40 lp/mm is used. So bottom curve for LF should be compared to the middle curve for medium format and DSLRs.
The MTF curves for the Zeiss Macro Planar 100/2.0 and the Leica APO Macro 120/2.5 are also attached.
As a side note, there are large format/medium format lenses from Rodenstock and Schneider intended for digital photography, those lenses are among the best with regard to MTF.
An interesting observation may be that Lloyd Chambers recently tested a Leica S2 and a Hasselblad H4D 50. He found the two Hasselblad lenses clearly lacking in sharpness and had sample images clearly demonstrating the deficit in sharpness.
Best regards
Erik
So I actually went through the trouble of digging this up, a comparison between an undisputedly "very good" medium format lens (the latest 80mm f2.8 planar for 6x6) and the "just awful" apo-sironar-s. Looking at its mtf at f5.6 over a 40mm image circle, the sironar-s drops from just over 80% in the center to slightly under 70% at the edges at 20 cycles/mm. The planar drops from 85% to worse than 40% at the edges. So the planar is sharper in the center but much softer at the edges. At 10 cycles/mm the sironar-s falls from over 90% to over 85%; the planar from around 95% to around 65%. So while the planar is sharper at the edges at f5.6, the sironar-s is significantly sharper across the frame. On these terms alone (mtf charts, the very terms you cite), it's hardly an awful lens.
But for a variety of reasons, this is a bad comparison. A better comparison would be at proper working apertures (f5.6 for the planar; f11-f16 for the sironar-s) comparing twice the cycles/mm on the medium format lens to what the large format lens produces (to compensate for large format having four times the surface area). Rodenstock only provides mtf at f5.6 and f22 so the comparison has to be made at f22, at which point diffraction is already hurting the lens' ultimate resolving power. But the sironar-s must also be traced to an 85mm radius and the planar to only 40mm.
In this fairer comparison, the sironar-s drops from just under 85% to just under 80% mtf at 10lp/mm. The planar drops from 85% to worse than 40% at the corresponding 20lp/mm. The sironar-s drops from just under 70% mtf to around 55% mtf at 20lp/mm. The planar drops from just under 70% mtf to around 20% mtf at the corresponding 40lp/mm. In this fairer comparison, were the mtf of the sensor not an issue (which of course it is), the medium format lens might be a tiny bit sharper in the center, but the large format lens would be far sharper toward the edges of the frame. The superior proximity of saggital and meridional mtf on the sironar-s results in an impressive lack of chromatic abberation.
So, if by "having some character" you "being a little less sharp in the center but much, much sharper and better corrected in practice because the frame is so big," then you would be right. The best modern plasmats have tons of character. All this said, a 36X24mm crop from large format is usually considerably softer than a frame of the same film from 135, which is inevitably softer than a full frame dSLR. But that's cropping 1/16th of the frame. Look, I'd shoot on a 5DII instead if I had the money to afford the camera and some tilt/shift lenses--but large format is just really good.
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Certainly there's snobbery associated with large format acquisition, particularly if the print isn't done digitally. The more the print cost to make and the more difficult it is to reproduce, the more perceived value there is in it. That said, the best prints that I've seen were optically enlarged from 8x10 film, so there are aesthetic reasons, too, for their value. Good digital prints look pretty close, though, up to any reasonable size.
The comparison you posted is a little unfair. 120mm is quite long on 645 whereas 180mm on 4x5 is a "normal" lens. Longer lenses are typically sharper across the frame (look at the mtf data for Canon's telephoto l primes: so good!). This is why the comparison between the 150mm rodenstock and the 80mm distagon is unfair if you look at the same image circle, as I mentioned, and why I then compared a 40mm image circle with an 80mm one to be fair.
And in terms of equivalent focal length, this http://www.s.leica-camera.com/summarit-s-1-2-5-70-mm-asph-cs/ would be closer to the 180mm Schneider. Not nearly as sharp as the 120mm. While the Schneider still does extremely badly in comparison at 20lp/mm, the sensor is three times larger in any dimension, so it only has to do a third as well to deliver equivalent sharpness across the frame. And its mtf curves go on to 100mm, but the image circle is only 80mm without lens movements, and within that range it's not so bad at all. Pretty comparable to, if slightly worse than, the Leica when surface area is taken into account, obviously much worse over the same surface area, though.
I'm not saying you could mount a large format lens on a dSLR and expect good results (although I've tried it and it's not so bad as you'd think), just that the criteria are different for large format and digital lenses. A large format lens has to cover a huge area; it's not going to be as fast or as sharp across it as a $5,000 leica lens covering a small sensor, but it's not designed to be and doesn't have to be to get equal performance overall. The tolerances involved in shooting large format are also quite poor so it's almost not worth it spending money to get a perfect lens. The flip side of that is you can do lens movements pretty dramatically in the field using the ground glass and a loupe for focusing and get good results consistently because the film plane is so big it's easier to manipulate. Using lens movements on a smaller sensor is way harder.
Anyhow, the moral of these mtf charts is I'm glad I bought the rodenstock lenses! And yes, they are intended for use with 4x5 film and I wouldn't trust them near a medium format back. I also couldn't afford a medium format back, conveniently. I looked at mtf charts, too, and was pretty distraught by them, but using the actual lenses impresses, and when you think about the whole system rather than "why is this not 16 times better than 135" it makes sense.
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Could anybody with high sense of compassion for the non-harvart members could traduce those graphics into a decent and resumed english?
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Hi,
When Charlie Cramer switched from 4x5" to to P45 he found that the P45 was a decent match for drum scanned 4x5" Velvia. The P45 is at 39 MP. 8x10" has four times the area compared to 4x5" so it is plausible that 160 MP may be needed to match it. On the other hand, large format don't have the MTF at high frequencies that DSLR lenses are the best of crop of MF lenses. Still, to compete with a 8x12" lens that performs decently at 20 lp/mm we would need an MF lens that has equivalent MTF at 80 lp/mm. On the other hand, 8x10" lenses are often used at f/22. At f/22 resolution and MTF are cut to half compared to f/11. So would we use a perfect lens on at f/11 on 4x5" and a similarly perfect lens on 8x10" at f/22 they would be equal in resolution and MTF (ignoring MTF of the film).
With digital sensor is replaced by film. We would need a perfect lens at f/5.6 to match the perfect 8x10" lens and of course "nail focus", avoid vibrations and so on.
I guess that some of the Leica lenses Rodenstock Apo Digitars are pretty close to perfect lenses. But we are talking expensive stuff.
There are many other aspects. Film flatness to begin with, focusing accuracy which may be easier to achieve at f/22 than at 5.6, vibrations, wind sensivity.
Best regards
Erik
I found a Burtynsky interview where he was explaining that the digital backs are going to pass the 100MP barrier ( 120 MP ) and when that will happen it will overcome the current large format film resolution.
So if I understand Burtynsky well, the current digital backs are still not capable of surpassing the 8x10 films resolution until they will reach 120MP. But it seems that his affirmation is contradicting the "datas that are disponible" in internet.
It would be nice if large format film users who also work with high end backs could comment on that matter.
Is the Burtynsky statement correct?
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Could anybody with high sense of compassion for the non-harvart members could traduce those graphics into a decent and resumed english?
Basically I'm just trying to justify my purchase of two apo-sironar-s lenses! (They're my most expensive lenses.)
In other words, I've found that while they perform unremarkably over a small area of the frame (at least by small format standards), the full image still looks great. Due to the increased sensor size (16 times the surface area of 135 film or an FX digital sensor), they only need to perform 1/4 as well as a dslr camera lens or 1/3 as well as a lens for 645 to give the same contrast and detail to the given frame size. And, according to mtf charts, they perform at least 1/4 to 1/3 as well as the very best! Which sounds terrible (and kind of is), but is pretty good in practice, since they're less expensive than the very best and allow for generous lens movements. And by normal working apertures (f11-f32 depending on focal length) you're losing most of your resolution to diffraction, not lens flaws, anyway.
That's why Rodenstock's digital lenses are so much more impressive. They bring the coverage down to a much smaller area and then increase the mtf accordingly.
Anyhow, the rough equivalency between 50 megapixels and 4x5 sounds perfectly reasonable to me based on prints I've seen. 4x5 should have the ability to hold a tiny bit more fine detail as per its own mtf charts, but digital looks sharper than film and lacks grain. I have been really impressed by the 8x10 enlargements I've seen. They put 4x5 to shame, but mostly in terms of tonality, not contrast. 100 megapixels could likely match that, though, but with a different "look." Stitching might be the ultimate solution, if the scene permits.
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I guess that some of the Leica lenses Rodenstock Apo Digitars are pretty close to perfect lenses. But we are talking expensive stuff.
There are many other aspects. Film flatness to begin with, focusing accuracy which may be easier to achieve at f/22 than at 5.6, vibrations, wind sensivity.
Best regards
Erik
Maybe not: as I understood it from night school, depth of focus at the film (not depth of field at the subject) is also a variable, with longer lenses having more available depth of focus (at the film plane) than do shorter ones, which flies in the face of what's usually expected. So, with larger formats using relatively longer lenses to cover the same angle of view and with those lenses being slower, maybe the ease of focussing the larger format having to use a smaller aperture to do so is similar to the problem that MF digi cameras seem to have finding correct focus at near-infinity, but for the opposite reason: with the large film there is too much depth to determine, with slower lenses, what's exactly the point of focus, and with the digi there's not enough to permit making the choices accurately even with faster lenses...
Always liked the basic split-image viewfinder in the Fs!
Rob C
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So can we sum up the approximate equivalences? Would this be about right, or is there any consensus?
1) 20+ MP FFDSLR ~ 645 film
2) 16.7 MP (37x37 mm) MFDB ~ 6x6 film [fewer pixels than the FFDSLR, but no AA filter, and >50% larger sensor]
3) 18 - 28 MP (33x44 mm) MFDB ~ 6x7 film [only very marginally larger CCD size than the 37x37 mm ones]
4) 60 MP (54x40 mm) MFDB ~ 4x5 film [nearly 4x more pixels and 4x more film area than the 16.7MP/6x6 case...although nowhere near 4x the CCD size, less than 2x in fact]
5) 150?? MP (70?? x 55?? mm) MFDB ~ 8x10 film [surely it will have to be a substantially larger digital sensor than 645...they can't keep dicing 645-format into ever smaller pixel units and call it "8x10"?!]
Anyway speaking from my own experience, I own a 37x37 mm MFDB and it does seem to match anything I did previously with 6x6 film.
Ray
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So can we sum up the approximate equivalences? Would this be about right, or is there any consensus?
4) 60 MP (54x40 mm) MFDB ~ 4x5 film [nearly 4x more pixels and 4x more film area than the 16.7MP/6x6 case...although nowhere near 4x the CCD size, less than 2x in fact]
5) 150?? MP (70?? x 55?? mm) MFDB ~ 8x10 film [surely it will have to be a substantially larger digital sensor than 645...they can't keep dicing 645-format into ever smaller pixel units and call it "8x10"?!]
Ray
If a 50mm sensor is equivalent to 5*4, you might need a 100mm sensor for 10*8, but an 8 micron 16 shot might give the best res/mm^2.
You might think that they will have to invent a camera bigger that 645, but the Sinar P3 etc. 10*10 lensboard cameras could house a sensor about 9*9cm, which would be a useful use of existing technology and a good compromise res/size/weight/cost. If you send me one on permanent load to test, I will not charge you for the idea!
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From my own experience shooting architecture/travel:
1) A P45+ is marginally superior in resolution to a scanned 4"x5" negative.
2) Three vertical P65 shots stitched together, with around 25% overlap, to yield a file of approximately 120MP, resolve significantly less than an 8"x10" scanned transparency and even a bit less than an 8"x10" scanned negative. This is with the very best current Rodenstock HRW lenses and very careful technique (tethered, digitech, weighted tripod etc.).
3) The P65 is significantly more colour accurate than film and terrific in mixed lighting conditions.
4) The scanned negative is way better for holding highlight detail and though not actually very colour accurate generally looks great once worked on in a way that is hard to achieve with digital. However, to get the most out of it one needs to produce 'raw' 16-Bit scans and the files are very demanding of Photoshop skills and very time consuming to spot.
5) Even though I generally apply grain to digital images a scanned negative has more grain than I would choose.
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Hi,
At large camera subject distance I'd assume that Depth Of Focus is only dependent on f-stop. See it as a cone of light exiting the lens. I presume that you would focus at near maximum aperture and stop down to f/22 where a large format lens seems to perform best. At large apertures on DSLRs focus shift may be a problem.
Best regards
Erik
Maybe not: as I understood it from night school, depth of focus at the film (not depth of field at the subject) is also a variable, with longer lenses having more available depth of focus (at the film plane) than do shorter ones, which flies in the face of what's usually expected. So, with larger formats using relatively longer lenses to cover the same angle of view and with those lenses being slower, maybe the ease of focussing the larger format having to use a smaller aperture to do so is similar to the problem that MF digi cameras seem to have finding correct focus at near-infinity, but for the opposite reason: with the large film there is too much depth to determine, with slower lenses, what's exactly the point of focus, and with the digi there's not enough to permit making the choices accurately even with faster lenses...
Always liked the basic split-image viewfinder in the Fs!
Rob C
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Hi,
I made some tests comparing Velvia in a Pentax 67 with an FF DSLR with 24.5 MPixels. What I found that the Velvia may have better resolution on high contrast detail than the FF-DSLR but the digital image generally was much easier to work with. Better DR, less noise better color. Also, when sharpness was evaluated using Imatest I found the FF DSLR significantly better den Velvia on 67.
My findings are here: http://echophoto.dnsalias.net/ekr/index.php/photoarticles/16-pentax67velvia-vs-sony-alpha-900
Knowledgable photographers like Charlie Cramer have found the Phase One P45 at 39 MPixel to be comparable with Velvia on 4x5", check here:
http://www.outbackphoto.com/artofraw/raw_28/essay.html
Charlie Cramers findings actually would indicate that 67 would be more like 12 MPixels, as 4x5 film is about 1.8 times larger than 67 film along one side. So is 39 MP equivalent to 4x5" than 6x7cm would correspond to 39/(1.8*1.8) -> 12 MP.
One of the advantages of digital images over film is that the digital image is generally quite smooth, specially at low ISO. Although early DSLRs had only 3 MP in resolution they were perceived competitive with film, although they lacked the actual resolution but the image structure was much smoother.
Whatever equipment we use, image quality is dependent on much more than sensor or film resolution. Only with exacting work can maximum performance be achieved.
Best regards
Erik
So can we sum up the approximate equivalences? Would this be about right, or is there any consensus?
1) 20+ MP FFDSLR ~ 645 film
2) 16.7 MP (37x37 mm) MFDB ~ 6x6 film [fewer pixels than the FFDSLR, but no AA filter, and >50% larger sensor]
3) 18 - 28 MP (33x44 mm) MFDB ~ 6x7 film [only very marginally larger CCD size than the 37x37 mm ones]
4) 60 MP (54x40 mm) MFDB ~ 4x5 film [nearly 4x more pixels and 4x more film area than the 16.7MP/6x6 case...although nowhere near 4x the CCD size, less than 2x in fact]
5) 150?? MP (70?? x 55?? mm) MFDB ~ 8x10 film [surely it will have to be a substantially larger digital sensor than 645...they can't keep dicing 645-format into ever smaller pixel units and call it "8x10"?!]
Anyway speaking from my own experience, I own a 37x37 mm MFDB and it does seem to match anything I did previously with 6x6 film.
Ray
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The question for the ultimate resolution on image capture devices can be fascinating. But there is no definite answer. Before I elaborate on the subject I'd like to point out that the fundamental difference in character of the capture medium and how it supports your vision will have a much greater impact on your imagery than some resolution advantage of one over the other.
Film resolution depends to a very large degree on the incoming contrast. If you have a line target of 2-3 stops contrast a good standard 135 format lens will be able to put down more than 100 lp/mm on most modern films. We have tested many films and verified the results by inspecting the film under a microscope. But if you have low contrast detail only separated by a small fraction of a stop your resolution on film might drop to just 20-50 lp/mm. I haven't made proper tests for low contrast resolution so this number is just an experienced guess.
Digital image sensors are highly efficient at detecting very low contrast levels. Thus their resolution only depends to a small degree on image contrast. The Bayer pattern may reduce the resolution in certain conditions depending on the color of the incoming light, the internal signal processing and the demosaicing algorithm.
On the question of how many MP you need to get all the detail in a perfectly exposed 8x10" film I can say that I usually drum scan mine at 3600 ppi to roughly 950 MP (almost 6 GB per image) which seems to be overkill. Of course at this resolution the image is not as sharp compared to the pixel level of a MFDB. But sometimes on high contrast structures there's so much detail on the film that it takes such pixel density to capture it. What's more important, if you're in for a very large prints, I'm talking about 72x92" lighjet at 300 ppi or 64x82" inkjet at 360 ppi, there are smoother tonal transitions compared to scans of lower resolution. So when large prints are in order it's always better to have these transitions optically scanned instead of relying on software interpolation. When I'm scanning I'm really trying to get all the information there is on the film down to the grain structure. I could post some samples if there's interest.
I think digital systems need to increase their sensor size to get in 8x10" territory. I'm not sure how much the sensel density can be increased without losing too much quality on other parameters besides resolution.
Common working f-stops on 8x10" are in the f/22 - f/45 range where you can get diffraction limited resolution on film. Shooting indoors DOF might even call for f/64. When you're not focus stacking DOF requirements can be the limiting factor for resolution.
If you do not intend to print overly big the large film format can be quite forgiving. And you can get pretty decent results from lower end scanners. A scan of only 1200 ppi already gives you 100 MP. It's a long range from pretty decent to the full potential of the format. For smaller formats that range is more narrow but when you intend to process digitally starting with a great scan to gives you some meat to work with. Speaking of scanners, Charles Cramer used a Tango drum scanner to come to his conclusions about 4x5". Although the Tangos are great pieces of equipment they lack the resolution to make use of the full potential of even 4x5".
One of the advantages of working with film is its scalability. You can scan the film or enlarge it to your desired print size and still get something real out of it even if it is just the physical material itself. With digital you're stuck with what you've got at the capture stage.
Erik, if you take the best commercially available lenses for different image formats and compare the MTFs and normalize the resolution with the image circle you can see that there's only a very slight advantage for larger formats. By normalization I mean for example to compare the 80 lp/mm graph of a 90mm digital MF lens over an 80mm image circle and the 20 lp/mm graph of a 360mm lens over a 320mm image circle. Checking the manufacturer's recommended working apertures is also a good indication that there's only a slight increase in overall lens performance for larger formats.
But for smaller formats it takes a much higher resolution capture medium to get all the detail that a top of the line lens can deliver. The larger the format the closer you can come to diffraction limited photography.
-Dominique
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I had my portfolio slapped down by Nadav Kander's agent earlier this year because I shot on MF digital rather than 5x4 film.
What she said was interesting, and something rarely discussed on forums like this which are essentially gear focused.
"With large format film you make different choices" was what she said.
I hated this, but on reflection, I decided she was right and wrong at the same time. I also decided that the machinery used was unimportant. Its the choices that are important. With this in mind I decided to leave my last two boxes of Provia 5x4 in the fridge and continue with digital.
Whatever technological objections or reasoning you apply, there will always be a place for different media in photography, and mostly it won't matter anyway, not to me. I prefer interesting pictures badly made to boring pictures made beautifully. If I was rich or very successful I'd buy an Aptus-II 12 because I could make technically better images than I can with 5x4 or 8x10 film. No contest, but it wouldn't make my pictures any better.
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"With large format film you make different choices" was what she said.
I hated this, but on reflection, I decided she was right and wrong at the same time.
I dont understand what she means. The difference she talks about is bwt film and digital, or is she talking about different types of film or what?
If the difference is digital vs film I cant see her point.
Since when different become better? Does she really believe that the same pro photographer will make a different composition with digital or film?
Of course if a photographer is starting his/her path or are in the middle of a reinvention the MEDIA will contribute to the construction of the new style a lot. But I guess this was a paid job, not and artistic journey so I fail to see her point. The places I can see where digital vs film produce different results (compositions) are the ones where the Photographer can't control the light and there is some action. And nowadays that case favors digital big time.
That doesn't mean she dont have a good point or even a veery good point. Is just that I am failing to see it.
Could you elaborate your inside in the meaning?
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I prefer interesting pictures badly made to boring pictures made beautifully. If I was rich or very successful I'd buy an Aptus-II 12 because I could make technically better images than I can with 5x4 or 8x10 film. No contest, but it wouldn't make my pictures any better.
A kindred spirit...
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Digital image sensors are highly efficient at detecting very low contrast levels. Thus their resolution only depends to a small degree on image contrast. The Bayer pattern may reduce the resolution in certain conditions depending on the color of the incoming light, the internal signal processing and the demosaicing algorithm.
-Dominique
Does nobody use Bayer-free-multi-shot?
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So when large prints are in order it's always better to have these transitions optically scanned instead of relying on software interpolation. When I'm scanning I'm really trying to get all the information there is on the film down to the grain structure. I could post some samples if there's interest.
Please do so if you can find the time. I am sure there would be a great deal of interest.
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. . . digital backs are going to pass the 100MP barrier ( 120 MP ) and when that will happen it will overcome the current large format film resolution.
To me, the resolution isn't as important as the camera movements. I find it much more difficult to get accurate camera movements on a small digital back than on an 8x10 or 4x5 camera.
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[quote author=SCHWARZZEIT link=topic=48241.msg402747#msg402747 date=1289985476
Erik, if you take the best commercially available lenses for different image formats and compare the MTFs and normalize the resolution with the image circle you can see that there's only a very slight advantage for larger formats. By normalization I mean for example to compare the 80 lp/mm graph of a 90mm digital MF lens over an 80mm image circle and the 20 lp/mm graph of a 360mm lens over a 320mm image circle. Checking the manufacturer's recommended working apertures is also a good indication that there's only a slight increase in overall lens performance for larger formats.
But for smaller formats it takes a much higher resolution capture medium to get all the detail that a top of the line lens can deliver. The larger the format the closer you can come to diffraction limited photography.
-Dominique
[/quote]
Please can you expand on this. From my own tests it is striking how the best large-format film lenses approach their diffraction limit at their working apertures. The best medium format lenses for SLR systems are only marginally better at their working apertures and do not approach diffraction limit. Given the substantially larger area of 4"x5" and 8"x10" to even 6x7, let alone the <645 of medium-format digital, this presents a considerable overall optical advantage to larger formats. Of course resolution is not purely a matter of optics and there is significant resolution loss from film/scanning as opposed to sensor capture.
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My own .02 from experience:
1) It's extremely difficult to get a "perfect" LF film capture. First off, film flatness is an issue, second, precise focus requires that your GG is in perfect alignment with the surface of the film in your film holder. And film holders can vary in film plane by several thousandths of an inch. And then film rarely is perfectly flat in the holder.
2) 8x10 is even less accurate in the above respects than 4x5 but;
3) It is much easier to critically focus the larger 8x10 image accurately as it has more CoC tolerance to begin with; even more so with 4x5 compared to current 6x45 MF.
4) Example: When I had my Betterlight scanning back, I could "see" where a 0.5mm change in focus extension would alter the exact PoF from a 210mm lens at f11 from 100 meters down to 10 meters...
5) Glass becomes a limiting factor as you move up in format as well, and this removes a significant portion of the "4x gains" in film area from 8x10. My best 4x5 lenses rendered as high as I could measure them, which was around 60 lpmm centrally (arguably these lenses could be rendering as high as 90 lpmm, but I couldn't confirm that with my test equipment); by comparison my best 8x10 lenses were in the mid 40's with one hitting 52 centrally. Clearly there are exceptions here in both directions, but I think these are pretty "comfortable" resolution numbers to use as a generalization from the best modern LF glass.
6) By contrast, I own MF lenses that clearly still resolve beyond a pixel on my MFDB which has a 6u pixel pitch. 6u pixel resolution basically means the sensor is theoretically capable of resolving a little over 80 lpmm for a linear black and white line pair, or around 55 if you go with Nyquist.
My own "conclusion" on how many pixels it took to match each medium, assuming the best possible glass being used for all mediums, was ~~50MP to match a perfectly captured and scanned sheet of 4x5 and ~~100MP to match a perfectly captured and scanned sheet of 8x10. Corollary comment here is even when taking extreme care in my set-ups, I got maybe a 30% hit on the "perfectly captured" part for either 4x5 or 8x10. Not saying the other 70% were unusable, far from it -- just not "perfect." (I had a much higher hit rate with the Betterlight because it had electronic focus confirmation and was of course a perfectly flat capture plane.)
For comparison, with my current MF digital set up, I find my DF body's auto focus to be more accurate a far higher percentage of the time of the time than I ever was with a 10x loupe and a GG, and of course obtaining correct exposure is immediately confirmable. Thus, I'd give my current 60MP MFD set up a quarter notch over 4x5 most of the time and maybe rate it a half notch behind my best 8x10 captures. Of course as soon as you factor in convenience, the film solution drops way down the ladder for me.
In the end, my own opinion is if you want to deal with it, 4x5 and 8x10 film still offer a very viable solution for generating the highest quality captures.
Cheers,
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Dominique,
since I gather that you have one of the world's finest drum scanners, would you mind posting a 100% crop, say 2-4 megapixels in size, of a 6GB 8x10 scan?
I would like to compare it to some 100% crops of mfdb shots made with technical cameras.
I have never seen a scan of this type and am very curious as to what the top end of drum scanners can extract at this point.
What is the file resolution of such a 6gb scan?
Kind regards
Paul
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[quote author=Jack Flesher link=topic=48241.msg402845#msg402845
My best 4x5 lenses rendered as high as I could measure them, which was around 60 lpmm centrally (arguably these lenses could be rendering as high as 90 lpmm, but I couldn't confirm that with my test equipment); by comparison my best 8x10 lenses were in the mid 40's with one hitting 52 centrally.
Cheers,
[/quote]
...so, if we want a really large print, and Apo-Digitars do not have enough image circle, shift-and-stitch on 5*7 with a good LF lens is a viable option, and a good alternative to pan-and-stitch?
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...so, if we want a really large print, and Apo-Digitars do not have enough image circle, shift-and-stitch on 5*7 with a good LF lens is a viable option, and a good alternative to pan-and-stitch?
LOL excellent point!
Actually, I left both 4x5 and 8x10 film at the same time (sold everything, lenses and cameras), and I told myself if I ever came back to LF film I would shoot 5x7 --- and for a few reasons: 1) most modern 4x5 lenses adequately cover 5x7; 2) a 5x7 camera is not significantly larger to carry than a 4x5 where an 8x10 certainly is; 3) I prefer the 4:3 aspect ratio most of the time, and it's an easy crop from 5x7 to 5x6.7; and 4) you net almost 2x the film area from 5x7 compared to 4x5 when both are cropped to a 4:3 aspect. (And with that 2x film area, I think you could comfortably shoot a shorter lens and forego the shift and stitch ;) ...)
You could do a lot of great landscape shooting with 5x7 camera, a few film holders and a 110 (SSXL), 180 and 300 lens kit...
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...so, if we want a really large print, and Apo-Digitars do not have enough image circle, shift-and-stitch on 5*7 with a good LF lens is a viable option, and a good alternative to pan-and-stitch?
LOL excellent point!
Actually, I left both 4x5 and 8x10 film at the same time (sold everything, lenses and cameras), and I told myself if I ever came back to LF film I would shoot 5x7 --- and for a few reasons: 1) most modern 4x5 lenses adequately cover 5x7; 2) a 5x7 camera is not significantly larger to carry than a 4x5 where an 8x10 certainly is; 3) I prefer the 4:3 aspect ratio most of the time, and it's an easy crop from 5x7 to 5x6.7; and 4) you net almost 2x the film area from 5x7 compared to 4x5 when both are cropped to a 4:3 aspect. (And with that 2x film area, I think you could comfortably shoot a shorter lens and forego the shift and stitch ;) ...)
You could do a lot of great landscape shooting with 5x7 camera, a few film holders and a 110 (SSXL), 180 and 300 lens kit...
I was thinking of shift-and-stitch with a digital back, using LF lenses... you would have to invent a stitching back with enough shift.
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Please can you expand on this. From my own tests it is striking how the best large-format film lenses approach their diffraction limit at their working apertures. The best medium format lenses for SLR systems are only marginally better at their working apertures and do not approach diffraction limit. Given the substantially larger area of 4"x5" and 8"x10" to even 6x7, let alone the <645 of medium-format digital, this presents a considerable overall optical advantage to larger formats. Of course resolution is not purely a matter of optics and there is significant resolution loss from film/scanning as opposed to sensor capture.
To come to that conclusion I did compare the MTF diagrams of the current Rodenstock lenses. Take the 40 lp/mm graph of the Digaron-S 60mm at f/5.6 for example, it runs very similar to what the Apo-Sironar-S 150mm does at f/11 for 20 lp/mm across twice the image circle. For 8x10" we can look at the Apo-Sironar-S 360mm which is only slightly better at f/22 for the corresponding lines across four times the image circle of the Digaron-S. This pattern even extends to Schneider's Fine Art XXL 1100mm lens which shows only a slightly better curve for 10 lp/mm at f/45.
The Digaron and Digitar lenses for technical cameras seem to be better than most MF SLR lenses. The best MTF for a medium format digital system I've seen so far is the Caldwell 120mm Macro UV-IR Apochromat. The overall optical performance seems to be very close to the Apo-Sironar-S 360mm. Of course the manufacturing tolerances on high resolution lenses for smaller formats have to be much tighter than for the big boys. So there might by a higher percentage of sample variations for digital lenses.
Here is a sample:
(http://www.high-end-scans.de/img/bilder/web/DV091221_01_120ppi.jpg)
This has been my first 8x10" capture. Even though I like the image itself there are a few problems that make it unusable, the bellows shading only being the most obvious. Every step up in format opens new pitfalls to pay attention to.
The lens was a Rodenstock Apo-Sironar-S 240mm at f/16 on Fuji Pro 160S for a little over six minutes exposure time. In fact I scanned this image at 4500 ppi (1.5 GP and 10 GB file size). Back then I was still trying to find the right master file size for my 8x10" images. I even scanned a central chunk of that film at 6000 ppi. At that resolution the full image would be 2.65 gigapixel in a massive 17 GB file. Are there any RIPs that could handle such a file?
I prepared crops at different resolutions to give you an idea on how much pixel density you need to store detail at various contrasts. The crops were sharpened and saved as quality 12 jpegs. From there you can draw your own conclusions.
6000 ppi - 2.65 GP (http://www.high-end-scans.de/img/bilder/web/DV091221_01_6000ppi_crop_s.jpg)
4500 ppi - 1.50 GP (http://www.high-end-scans.de/img/bilder/web/DV091221_01_4500ppi_crop_s.jpg) (this is a 100% crop from the master file)
2400 ppi - 400 MP (http://www.high-end-scans.de/img/bilder/web/DV091221_01_2400ppi_crop_s.jpg) (downsized from the 4500 ppi scan)
1440 ppi - 150 MP (http://www.high-end-scans.de/img/bilder/web/DV091221_01_1440ppi_crop_s.jpg) (downsized from the 4500 ppi scan)
I didn't bother to spot the file. Spotting a multi-GB file is a laborious and time consuming process.
I'm reluctant to pinpoint the resolution of 8x10" to one number. I see it as a range where it takes a very high resolution scan to capture the finest high contrast details while on the other hand the lower contrast textures are getting lost in the film's grain structure. But like I said earlier I see the greatest advantage in smoother tonal transitions in very large prints compared to upscaling by software. The type of film used of course also has an impact. The Fuji Pro 160S has an excellent MTF. It's very fine grained for a color neg but coarser than the new Kodak Ektar 100. Color negs do shine in high contrast situations where the full dynamic range of the film is used. Under normal medium contrast light reversal film has a finer grain appearance.
What is the file resolution of such a 6gb scan?
Typical pixel dimensions for a 3600 ppi file of 8x10" film after cropping the film holder's edges is 34,700 x 27,500.
My own "conclusion" on how many pixels it took to match each medium, assuming the best possible glass being used for all mediums, was ~~50MP to match a perfectly captured and scanned sheet of 4x5 and ~~100MP to match a perfectly captured and scanned sheet of 8x10. Corollary comment here is even when taking extreme care in my set-ups, I got maybe a 30% hit on the "perfectly captured" part for either 4x5 or 8x10. Not saying the other 70% were unusable, far from it -- just not "perfect." (I had a much higher hit rate with the Betterlight because it had electronic focus confirmation and was of course a perfectly flat capture plane.)
Jack, even though I disagree with your MP equivalents for perfect LF exposures on film I do agree that it's almost impossible to make use of the format's full potential for the various reasons you stated. Often it's just some unintentional fall-off in sharpness that doesn't ruin the image but it does compromise the quality. I do mostly long exposures where the wind and the light travelling through the atmosphere can cause all sorts of trouble over time. I even heard of the possibility that the film could buckle inside the holder. Some faults cannot be traced back easily.
May I ask which lenses and what types of film you used for 8x10" back then?
...so, if we want a really large print, and Apo-Digitars do not have enough image circle, shift-and-stitch on 5*7 with a good LF lens is a viable option, and a good alternative to pan-and-stitch?
I was thinking of shift-and-stitch with a digital back, using LF lenses... you would have to invent a stitching back with enough shift.
Don't you think that it would be more effective to use a DSLR and a long lens on a nodal point adapter for super sized stitching? This way you're always using a high quality image circle of a long lens.
-Dominique
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I have read Roger Clarks reports with great interest. Mainly talking about 35 mm but I guess the fundamental issues can be extrapolated?
http://clarkvision.com/articles/film.vs.digital.summary1/index.html
(http://clarkvision.com/articles/film.vs.digital.summary1/film.vs.digital.35mm-d.gif)
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6000 ppi - 2.65 GP (http://www.high-end-scans.de/img/bilder/web/DV091221_01_6000ppi_crop_s.jpg)
4500 ppi - 1.50 GP (http://www.high-end-scans.de/img/bilder/web/DV091221_01_4500ppi_crop_s.jpg) (this is a 100% crop from the master file)
2400 ppi - 400 MP (http://www.high-end-scans.de/img/bilder/web/DV091221_01_2400ppi_crop_s.jpg) (downsized from the 4500 ppi scan)
1440 ppi - 150 MP (http://www.high-end-scans.de/img/bilder/web/DV091221_01_1440ppi_crop_s.jpg) (downsized from the 4500 ppi scan)
It looks to my eyes that you need the 2400ppi to capture all the detail - the venetian blinds provide a handy source of fine modulation. 1440 ppi is definitely too low.
Typical pixel dimensions for a 3600 ppi file of 8x10" film after cropping the film holder's edges is 34,700 x 27,500.
-Dominique
Well then; scaling 34,700 x 27,500 from 3600 ppi to 2400 ppi gives a 424 Mpix file. Now we know what 8x10 is capable of! It certainly exceeds 152 Mpix (1440 ppi)
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Well then; scaling 34,700 x 27,500 from 3600 ppi to 2400 ppi gives a 424 Mpix file. Now we know what 8x10 is capable of! It certainly exceeds 152 Mpix (1440 ppi)
Well, when you think about it is hardly surprising, is it. Just imagine a digital sensor that big (8x10), or even 5x4.
John
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Well, when you think about it is hardly surprising, is it. Just imagine a digital sensor that big (8x10), or even 5x4.
John
I'm not in the least surprised. My emphasis was there, rather, to prod those who would claim that you can get 8x10 quality in << 150 Mpix.
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Basically I'm just trying to justify my purchase of two apo-sironar-s lenses! (They're my most expensive lenses.)
Don't worry about it - I have a couple of Apo Sironar (150 S and 180 Makro), and they hold their own against my digital lenses . ;)
In other words, I've found that while they perform unremarkably over a small area of the frame (at least by small format standards), the full image still looks great. Due to the increased sensor size (16 times the surface area of 135 film or an FX digital sensor), they only need to perform 1/4 as well as a dslr camera lens or 1/3 as well as a lens for 645 to give the same contrast and detail to the given frame size. And, according to mtf charts, they perform at least 1/4 to 1/3 as well as the very best! Which sounds terrible (and kind of is), but is pretty good in practice, since they're less expensive than the very best and allow for generous lens movements. And by normal working apertures (f11-f32 depending on focal length) you're losing most of your resolution to diffraction, not lens flaws, anyway.
Well put, only I don't see the value of the mtf charts if the conclusions are what you say they are. Also keep in mind LF lenses where almost never developed for sheet film only .
[/quote]I have been really impressed by the 8x10 enlargements I've seen. They put 4x5 to shame, but mostly in terms of tonality, not contrast. 100 megapixels could likely match that, though, but with a different "look." Stitching might be the ultimate solution, if the scene permits.
[/quote]
Good point; tonality is where the larger LF formats really shone. You loose an incredible amount of 'data' when you make an analogue print, yet the tonality somehow gets through .
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...so, if we want a really large print, and Apo-Digitars do not have enough image circle, shift-and-stitch on 5*7 with a good LF lens is a viable option, and a good alternative to pan-and-stitch?
Don't you think that it would be more effective to use a DSLR and a long lens on a nodal point adapter for super sized stitching? This way you're always using a high quality image circle of a long lens.
-Dominique
I have bought an HC 300mm with this in mind... but Nodal point pan-and-stitch is less than ideal for architecture...
Would a hex-stitched image from a good 400mm LF lens be better than a multi-shot with an Apo-Digitar 210mm? If the image included a moving boat, 400mm LF might be better than single shot hex-stitch?
If I do not intend or expect to use film again, is there any point in keeping my LF kit?
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Jack, even though I disagree with your MP equivalents for perfect LF exposures on film I do agree that it's almost impossible to make use of the format's full potential for the various reasons you stated. Often it's just some unintentional fall-off in sharpness that doesn't ruin the image but it does compromise the quality. I do mostly long exposures where the wind and the light travelling through the atmosphere can cause all sorts of trouble over time. I even heard of the possibility that the film could buckle inside the holder. Some faults cannot be traced back easily.
May I ask which lenses and what types of film you used for 8x10" back then?
Don't you think that it would be more effective to use a DSLR and a long lens on a nodal point adapter for super sized stitching? This way you're always using a high quality image circle of a long lens.
-Dominique
No offense taken -- those stated values were more or less subjective impressions by myself and associates I respected based on our own results over our combined years of shooting side-by-side and comparing.
My preferred films back then were,
4x5: Pro160S, Portra 160 NC, and Ektacrhome E100 G
8x10: Pro160S, Portra 160 NC, E100 G and my all time favorite, Vericolor III. Long discontinued, but I had a reserve supply of it :)
My preferred lenses:
4x5: 65mm and 90mm SA MC Linhof badged, 110 SSXL, 150 APO Symmar L, 240 G Claron and 305 G Claron
8x10: 210 SSXL, 305 G Claron, 450 APO Ronar
I tested my lenses back then with the Betterlight scanning back in highest resolution mode.
Re DSLR and stitching. Yeah, I even built a custom camera out of a Horseman L specifically to do that, and have the tee-shirt. At the end of the day, you got enough shadowing from the DSLR's mirror box it limited your widest AoV to basically a normal. Then you had the issue of subject movement during the minimum 12 frames of capture, often even 24 frames and sometimes 48 frames. In the end, it was far easier to shoot film and scan, and usually with superior results. The BL scanning back was awesome as respected IQ and DR, and far more convenient and better IQ than the DSLR stitch approach, but it also suffered from subject movement. The BL also had the added disadvantage of needing power and be tethered to a laptop which was inconvenient in the field to say the least --- again, I found film and scanning far more convenient. (FWIW, there was an intangible Zen-like quality to exposing film on a view camera that I found very enjoyable, more so than direct digital, and that's probably the only reason I would go back to shooting a view camera and film again.)
Cheers,
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FWIW -
Ed shot mostly with 4x5 a while back - the Linhof and the Grandagon 75mm 4.5 a lot.
Of late he has been with the Blad 39 then the 50 and now the 60.
Ed is a super nice guy and very generous with his time and knowledge. He is diligent in terms of technique and applying discipline to the photo.
His lab in Toronto is great and the staff there super knowledgeable - if you want to get the most of your images they can sure help.
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Hi,
I'd suggest that there is a lot of snobbery involved. On the other hand there is another factor. Different optical systems have a specific signature. With digital we may have a tendency for perfection. Large format lenses were never perfect, if you look at MTF data for any of them they are just awful, but they may have some kind of character. Rodenstock Imagons come to mind.
So I'd suggest that it is snobbery and perception.
There is also an aspect of workmanship. Shooting a single sheet of film costing perhaps 50 USD (including processing) vs. shooting images with very little marginal costs.
Best regards
Erik
If MTF charts were the be all and end all in choosing a lens and equipment life would be much simpler. I never compared the mtf performance of my lenses on 35mm 6x6 or LF or my digital, (I never look at mtf charts these days) regardless of what they were, the bigger the sheet of film used the better technical quality image was recorded. I shoot LF on occasion for the fun of it, like a painter takes an easel and paints into the country instead of copying a snapshot. I don't think it's all snobbery on the photographers part, although the galleries like a yarn to spin. Spot on with the workmanship thing, nothing like a bag of money to concentrate the mind. The whole experience and thought process using film and especially LF is different to digital. You need to make a lot more decisions about how the image will look upfront with film than you do digital.
I don't get this obsession with resolution, it is another aspect that digital has amplified the importance of, a bit like everyone now wants a fast lens to shoot the background out of focus. The next craze will be aperture blades when everyone realises it's the shape of the hole that gives good bokeh. Who really cares wether a P65 or 10x8 can show a couple more whiskers on a chin at 50 paces. It's content and always has been that counts.
It's a funny old world where we measure technical perfection a thousand ways and believe the better the figures the more emotionally moved we will be when looking at a picture. I reckon the finest old masters with a brush and oil painted at about 6 - 8 mega pixels resolution, yet we marvel at the detail they brought to life.
Cheers,
Kevin.
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I don't get this obsession with resolution, it is another aspect that digital has amplified the importance of, a bit like everyone now wants a fast lens to shoot the background out of focus. The next craze will be aperture blades when everyone realises it's the shape of the hole that gives good bokeh. Who really cares wether a P65 or 10x8 can show a couple more whiskers on a chin at 50 paces. It's content and always has been that counts.
It's a funny old world where we measure technical perfection a thousand ways and believe the better the figures the more emotionally moved we will be when looking at a picture. I reckon the finest old masters with a brush and oil painted at about 6 - 8 mega pixels resolution, yet we marvel at the detail they brought to life.
Cheers,
Kevin.
I agree about the first part. Resolution is only one of several aspects, and people/media tends to be fixated on one at a time, when it is the whole that matters.
I think that photography is (can be) both a technical and artistic venture. That is part of what appeals to me. And I find the artistic part a lot harder than the technical one.
I think that doing good, repeatable, relevant measurements is a good base for doing camera (equipment) reviews. It serves as a counterpoint to reviewer preferences and biases when subjective impressions are reported.
-h