Luminous Landscape Forum
Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: dalethorn on April 28, 2008, 12:12:49 am
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I use point & shoots, which I imagine few of you do. Since their pixel specs are usually way overrated, I wonder if there's a better way to rate them. For example, if I were to take a series of landscape pics under ideal lighting conditions, do minimal or no post processing, then make several copies of each at different sizes (say, 3072x2304, 2560x1920, 2048x1536 etc.), and view all copies at full size on screen, could I say that the True Effective Pixels is the smallest size at which I can plainly see all of the detail of the original, ignoring edge artifacts etc. added by the in-camera processing? I ask this because my highly-promoted 9mp camera appears not to have any real detail beyond about 3mp.
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The real question is one of enlargement of the pixels, which are themselves limited by the lens and by your technique (whether you are using a tripod and mirror lock-up for instance). Furthermore, the photosites that generate the pixels you get from your tiny little P&S sensor are much smaller than the photosites my DSLRs use to generate their pixels; add to that better lenses and more careful processing of those pixels (I always shoot in RAW for instance) and there is a dramatic difference in how much larger a print from a DSLR can be compared to a Digital P&S.
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Dalethorn wrote:
I ask this because my highly-promoted 9mp camera appears not to have any real detail beyond about 3mp.
I suppose this varies from make to make and model to model, but in my experience resolution is the one area in which point & shoots have not been especially weak. I've used a variety of both point & shoots and dSLRs and have consistently found the amount of detail in the point & shoot images to be in the ballpark of their megapixel count.
This is confirmed by the careful testing in the reviews at dpreview.com, which gives resolution figures on the page just before the conclusion. For example, the 10 mp Canon G7 measures at 1775 horizontal LPH and 1850 vertical, while the 10 mp Canon D40 weighs in at 2100 and 1800, respectively. The only caveat here is that these are measured from the in-camera JPEGs, not from the RAW.
So if you're only seeing 3 mp of detail, you might want to consider whether you have a defective unit.
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Due to the small pixel dimensions P&S sensors lose resolution due to diffrction earlier than dslrs (to date at any rate - pixel sizes are shrinking there as well). However, we have a 5Mp and a 9 or 10Mp P&S and both seem to be able to provide resolution that is consistent with the numbers. Against this is the noise level that means the files are less malleable, even at base iso, than an dslr file and they tend not to print as well at bigger sizes.
Mike
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Correct me if I'm wrong (and my camera is not defective), but we seem to be missing the point. A lab can measure pixels and "resolution", but cannot see the difference between actual subject and filler, i.e. either "corrected" noise or interpolation. So back to the question - since the proof is in the viewing, am I wrong to suggest that reducing the image to the smallest size that retains the actual detail is proof of the real effective resolution?
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So back to the question - since the proof is in the viewing, am I wrong to suggest that reducing the image to the smallest size that retains the actual detail is proof of the real effective resolution?
No. The trick is to accurately define the threshold size below which detail starts disappearing, and account for resizing artifacts. Probably the best way to do this would be to shoot a resolution test chart, and see how much you can shrink it before the smallest resolved details disappear.
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And it gets trickier, since those tests are almost always done with a black and white graph. If you switch to color, the nasty Bayer filter rears its head. Red and blue on a typical sensor are much lower resolution than the green channel.(typical distribution is 25%/25%/50% R/B/G) As a result, it takes 7 or 8 of these sub-pixels to create a single full color point on the film.
The camera has to then use its internal software to interpolate and anti-alias what it's seeing(or in the case of RAW, the software has to do this) Point and shoot cameras of course tend to have very poor methods of doing this and often won't shoot in RAW format. True, you can see some fine details around edges and such, but they tend to have off-color areas, moires, halos, and whatnot, because while the resolution is technically there, it's only partial color resolution.
So shooting color, you effectively have about 0.6-0.65x the listed resolution in actual full-color locations/true pixels in each dimension. And, yes, their marketing departments lie - huge surprise there... 12MP is actually closer to 4.3-5.0 physical full color locations. Which is why the Sigma at 4.6MP looks about identical to a 10-12MP CMOS sensor. Yes, I know Sigma lists theirs as 14MP, but it's a true 4.6MP.
Try shooting a resolution chart printed in red, blue, and green. I'm amazed that more places that review cameras don't do this.
http://www.ddisoftware.com/sd14-5d/ (http://www.ddisoftware.com/sd14-5d/)
A review that points this out. The problem isn't the lens or the camera, but that we need a new generation of sensors that are free of these problems. I've nearly taken Foveon out of consideration, though, since they seem to be unable to get their act together and make a deal with Nikon or some other major player.
A true 8MP camera would be an ideal replacement for 35mm film. Too bad Foveon and Sigma seem to be stuck in first gear in getting it to market.
EDIT: Why I said 8MP?
A typical D-Lab scans 35mm film at 3000*2000 fixed resolution. This is roughly 2200 DPI. 400DPI Dye-sub as a result. A more reasonable limit would be 2400DPI, though, which would net a 3400*2265 scanned area. Almost all dedicated personal scanners default to this resolution as well, or very close to it. This is roughly equal to about 420lines per inch on Dye-sub, which is where most experts agree that you don't gain anything - at least for color. Most D-labs kludge it at 400 lines per inch and call it a day.
So 2400DPI scanned is a good compromise and what we should aim for to consider 35mm film "dead"/rendered moot.
Anyways, 3400*2265 is ~7.7MP of actual true resolution. That's 7.7 with a Foveon type sensor or about 5200*3500 for a Bayer pattern.(16MP at a 0.65 ratio) It's not a lot different in terms of linear resolution - 5200 vs 3400(roughly like 300 DPI Dye sub vs 400DPI), but of course, the multiplier once you add in both dimensions makes it grow to silly numbers.
That said, many DSLRs do give you 16+MP now and can give you film like results after they have been processed and tweaked. I said 8MP because it's not common to find sensors in exactly 35mm film aspect ratios these days, so you usually have to go to something like 3500*2400.
MF, btw, by the same standards, would require 30MP actual resolution, or closer to 60 with a digital back to replace 120 film. The sensors are larger, and the software is generally better, making it closer to a 0.7 ratio instead of 0.65 or so. I'd rate consumer level point and shoots at 0.6 or worse - which is why they look washed out and dull - there's just too little color data/saturation. They just came out with 40MP digital backs, so 60MP or so and replacing 120 film entirely isn't that far off.
*note* - this isn't subjective measurements. Most pros consider 120 film dead with 40MP, or close enough to where they don't care. But from a technical standpoint, 60MP is about where you'd have to go to actually make it moot. I give the industry 2-3 years to get to this point.
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What got me into this was all or nearly all of the Internet camera site editors and pundits *insisting* to the mfr's that small cameras with big zooms should start out with wide angle (28 mm) so users can take better landscape photos. I insisted (to no avail) that cameras like the TZ5 would benefit more from a 35-350 mm range than 28-280, since landscapes would just show pixel smear at full view. The TZ1 in fact was 35-350. Unlike those pundits I suppose, I have the LLVJ 1 to 12 in hand in the 4-packs, and am well acquained with what a landscape can or should look like. Perhaps a few well-placed Internet postings reviewing these "landscape-ready" pocket cameras as they really are will help shake some of the camera mfg. spokespeople out of their lethargy.
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Sounds good I'd like to read it.
Oh - about Foveon... I think the reason they aren't coming out with a better sensor is because Canon and the others beat them to it.(16-21mp). If I was them, I'd be pouring money into a ~30MP digital back(they'd probably market it as 90mp - sigh). That would make a big impact on pros as well, since the technology seems more geared towards situations where color balance and saturation are important. Most consumers just don't care by comparison.
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I had a similar view of the need to have lots of pixels to equal even 35mm film, but when I bought my 5D I was astounded at just how capable it is in comparison with 35mm. Small sensor P&S cameras are very different and 10 or 12Mp on a small sensor isn't the same as 35mm film - but it's not just resolution that's lacking but the way the image is drawn - there's more noise (certainly at iso 100+ on mine) and much more depth of field.
Also, whilst it's certtainly the case that Bayer sensors do not resolve with the same efficiency as a sensor that could (efficiently) record all colours at each photosite, other people on here who are more knowledgeable than I have suggested that they are capable of resolving at about a 70 to 75% ratio. In part this may be because the world does not comprise single colours, but it supports the observation that a 4.6Mp foveon should be similar in resolution to an 8 or 9ish Mp Bayer camera. I've not tested just observing.
Motly, I would just say that there are some significant differences in the way small sensor cameras draw compared to 35mm film, and that it's worthtrying out a couple of dslrs as you might be surpirsed by the results.
Enjoy
Mike
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Redundant reply text removed.
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Two thoughts here:
I never calibrated a monitor, but have had several in my vicinity for years - a few laptops and desktops with both CRT's and flatscreens. I've displayed my better images on the various screens and learned to make the adjustments that I felt would have the best longevity for proper color. True, the P&S images tend to have the washed-out look, but that's not the only problem. My question here is, do monitors and their video drivers have a problem analogous to audio gear, where "frequency response" isn't flat, but has spikes and resonances? Do any of the monitor calibrations correct for uneven color reproduction?
Second thought: When I bought my Nikon 8800 it had a 2/3 sensor, and a few months later I bought a Casio EXZ1000 pocket camera with a 1/1.8 sensor, which Casio upgraded to 1/1.7 with the EXZ1200. I took photos of the park service's welcome board at Bolsa Chica with both, side-by-side, and can swear that the Casio image was the equal of the Nikon in every way, given slight color adjustments. But today all of the "superzoom" 18x cameras are using smaller 1/2.33 or 1/2.5 sensors. This sounds like good news for DSLR users, of course. But is it really? Take a long look at CameraLabs.com to see who's buying most of the DSLR's. If this is the wave of the future, the future looks grim.
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Two thoughts here:
I never calibrated a monitor, but have had several in my vicinity for years - a few laptops and desktops with both CRT's and flatscreens. I've displayed my better images on the various screens and learned to make the adjustments that I felt would have the best longevity for proper color. True, the P&S images tend to have the washed-out look, but that's not the only problem. My question here is, do monitors and their video drivers have a problem analogous to audio gear, where "frequency response" isn't flat, but has spikes and resonances? Do any of the monitor calibrations correct for uneven color reproduction?
Second thought: When I bought my Nikon 8800 it had a 2/3 sensor, and a few months later I bought a Casio EXZ1000 pocket camera with a 1/1.8 sensor, which Casio upgraded to 1/1.7 with the EXZ1200. I took photos of the park service's welcome board at Bolsa Chica with both, side-by-side, and can swear that the Casio image was the equal of the Nikon in every way, given slight color adjustments. But today all of the "superzoom" 18x cameras are using smaller 1/2.33 or 1/2.5 sensors. This sounds like good news for DSLR users, of course. But is it really? Take a long look at CameraLabs.com to see who's buying most of the DSLR's. If this is the wave of the future, the future looks grim.
[a href=\"index.php?act=findpost&pid=192474\"][{POST_SNAPBACK}][/a]
to your first question, yes monitors can be non-linear and if not calibrated give widely varying results. IMages that look fine on my monitor at home are horrible on my office lcd.
Can you expand on the grim future please?
Mike
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Since mfr's are switching to smaller sensors on P&S's (note: 1/1.7 on pocket camera 2 years ago; 1/2.33 on large superzoom today), and since DSLR's are increasingly being marketed to non-serious photographers, and since marketing triumphs over reason and logic, I see a clear and unmistakeable trend to dumb down the new product releases.
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Since mfr's are switching to smaller sensors on P&S's (note: 1/1.7 on pocket camera 2 years ago; 1/2.33 on large superzoom today), and since DSLR's are increasingly being marketed to non-serious photographers, and since marketing triumphs over reason and logic, I see a clear and unmistakeable trend to dumb down the new product releases.
[a href=\"index.php?act=findpost&pid=192502\"][{POST_SNAPBACK}][/a]
I saw a couple of people in a shop the other day and one was saying to the other, 'I really should get of of those dslr things'. Clearly just the next must have after the P&S, and probably less suitable for their needs.
Dumbing down is the inevitable result of turning items into commodities. On the other hand there remain lots of people who are willing to pay for high quality equipment. I hope though that it doesn't turn into the same esoteric melee as high end audio, where magic seems to be half the equation:)
Perhaps strangely, I have something of a problem with the UKs foody trend, where supermarkets sell 'special' food at higher prices. Usually the special food is what they should really have been selling all along, unlike the cut price dumbed down food that the british consumer expects to pay next to nothing for.
\rant mode off
Mike
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I had a similar view of the need to have lots of pixels to equal even 35mm film, but when I bought my 5D I was astounded at just how capable it is in comparison with 35mm. Small sensor P&S cameras are very different and 10 or 12Mp on a small sensor isn't the same as 35mm film - but it's not just resolution that's lacking but the way the image is drawn - there's more noise (certainly at iso 100+ on mine) and much more depth of field.
True. The software and in-camera processing is getting to be better, but it's really a kludge. In a perfect setup, none of that would be required. Thankfully, though, most good DSLRs are all at the 16MP or so range and have nice, big sensors as well. They really do look a lot like film.(saturation and dynamic range and so on aside) That the 5d can almost kludge its way to look like film is impressive.
Also, whilst it's certainly the case that Bayer sensors do not resolve with the same efficiency as a sensor that could (efficiently) record all colors at each photo site, other people on here who are more knowledgeable than I have suggested that they are capable of resolving at about a 70 to 75% ratio.
With the move towards smaller and smaller sensors, I see the exact opposite happening. Some pocket AF cameras I'd rate as closer to 50% due to tiny lenses and microscopic sensors. 70% is about it for a Bayer type sensor without software and filters and such getting involved in the mix. It's a technological problem inherent in the design itself. Much like how you can't ever get 50% efficiency out of a 4 stroke engine and never will. To get higher output, you need a turbine or other technology. And the same holds true for cameras. The fact is that the Bayer technology has pretty much run its course and we need a major new method. One that captures the dynamic range and saturation of film more accurately, since resolution is at or close to being solved.
Foveon looks stunning, but the resolution is closer to 110 film. I'm no longer expecting anything meaningful from them, though. Fuji has a dual layer sensor, though, which appears to fix the dynamic range problem. This looks like it might be a partial solution. The photos it takes are noticeably more realistic looking than most cameras, since it is basically bracketing - but doing it in-camera off of a single shot.
(two sensor grids overlapped - each set a stop or two apart from each other, then blended, since there's 0 pixels out of place/it's taken at the same time)
http://www.outbackphoto.com/reviews/equipm..._S5_review.html (http://www.outbackphoto.com/reviews/equipment/fuji_s5/Fuji_S5_review.html)
Looks promising, but it's only ~6MP. We need 12MP or more. But it does seem to be better than the Sigma by a tiny bit, mostly because of the extra resolution. I'd rate this as equal to about 70% on the above scale. It has a better saturation and dynamic range - more like a typical DB. But it needs more pixels as well to really replace film and also compete with the "big boys".
P.S. look at the second set of photos. There's no way a typical DSLR would see anything inside that upper floor behind that glass. And, it uses Nikon lenses. I hope they make a 12-16MP version of this soon.
http://www.bythom.com/s5review.htm (http://www.bythom.com/s5review.htm)
Another review.
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"Most interesting is that the expanded dynamic range all happens above middle gray, which is exactly where most DSLRs have their least capability (I've written before that most DSLRs are asymmetrical in their ability to capture values below and above middle gray). If you're dealing with wedding dresses, white bird plumage, or anything else that has detail at the top of the highlight range, the S5 Pro has the ability to pull in two more stops of that."
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They have a new camera out this summer. We'll see if they fix some of the problems .
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True. The software and in-camera processing is getting to be better, but it's really a kludge. In a perfect setup, none of that would be required. Thankfully, though, most good DSLRs are all at the 16MP or so range and have nice, big sensors as well .
[a href=\"index.php?act=findpost&pid=192571\"][{POST_SNAPBACK}][/a]
I disagree with practically every assertion you have made in this thread. My D300 has a 12 MP DX sized sensor and I would stack it up against 135 format film without any worries. The resolution is excellent and the DR is a comfortable 8.5 stops. The biggest problem with Foveon sensors is that they get noisy at relatively modest ISOs; which is another way that my D300 kicks butt on both Sigma DSLRs and film.
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Thankfully, though, most good DSLRs are all at the 16MP or so range and have nice, big sensors as well. They really do look a lot like film.(saturation and dynamic range and so on aside) That the 5d can almost kludge its way to look like film is impressive.
[a href=\"index.php?act=findpost&pid=192571\"][{POST_SNAPBACK}][/a]
That would be just 2 dslrs with 16+Mp and full frame sensors at present - and one is out of production.
In my experience the 5D is comprehensively better than 35mm film for actual prints up to about 30 by 20. At larger sizes the differences become more apparent, but for most work film doesn't win out.
Mike
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The main point of this thread was to discuss the mfr's design trends, and explore the outer limits of sensor capability. Certainly DSLR sensors won't capture anything comparable to scanning backs, so they have a long way to go. My interest is in smaller cameras, and my opinion is that given the *negative* trends there, the implications for DSLR's are also bad, due to market pressures and the dumbing down of the equipment in general. You may see progress for awhile, but things can change. You can get a "superzoom" mini-camera for handheld wildlife shots at ~500mm that will produce a usable image if the lighting is good, so try to duplicate that with a DSLR - handheld. You might, but it's going to be awfully big and heavy. And I don't see any relief there. It did happen in music players, it didn't happen in laptop computers, and I bet it won't happen in DSLR's.
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Certainly DSLR sensors won't capture anything comparable to scanning backs, so they have a long way to go.
You can get a "superzoom" mini-camera for handheld wildlife shots at ~500mm that will produce a usable image if the lighting is good, so try to duplicate that with a DSLR - handheld. You might, but it's going to be awfully big and heavy. And I don't see any relief there.[a href=\"index.php?act=findpost&pid=192652\"][{POST_SNAPBACK}][/a]
Your expectations regarding DSLRs are unrealistic. Frankly, even a DX or APS-C DSLR with a 400mm VR or IS lens attached to it will spank any P&S with a "superzoom" lens. The extra weight of a bigger sensor and bigger glass you get using a larger format is unavoidable if you want to increase image quality and to gain more DOF isolation.
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I disagree with practically every assertion you have made in this thread. My D300 has a 12 MP DX sized sensor and I would stack it up against 135 format film without any worries. The resolution is excellent and the DR is a comfortable 8.5 stops. The biggest problem with Foveon sensors is that they get noisy at relatively modest ISOs; which is another way that my D300 kicks butt on both Sigma DSLRs and film.
[a href=\"index.php?act=findpost&pid=192589\"][{POST_SNAPBACK}][/a]
You are, of course, entitled to that opinion. I was merely talking about theoretical limits and what is required to truly replace film at all levels. Like a typical DB, most people look at the new 40MP models and shrug their shoulders and consider it good enough. 12MP with a large sensor is very close to 16MP, so the 5D could blur the line from time to time. But as others have said, it's not *quite* a total replacement for film at 12MP.
I consider 2400dpi scanned to be the lower limit to replace film, since every scanner on the market does at least this with 35mm film, and most of the D-Labs also are about this resolution as well. That means a lot of data, since that 2400dpi doesn't have micro lenses, moires, anti-aliasing, or other factors affecting it. It's 2400dpi with full color at every pixel. That pushes the bar up quite a bit for digital due to the way Bayer patterning works.
Now, whether we call it 60% or 70% or 75% aside, the fact is that a Bayer sensor has to be higher resolution to replace film because of these inherent design flaws. There is some loss of information that software can't really get back fully due to the lower percentage of red and blue sensors. So you have to shoot at higher resolution and then drop it back down with software to get that smooth and clean look of good film.
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Actually I don't have a problem with "more weight" as you say, but when "more weight" is ten times more, I think it's disingenuous to call that "more weight".
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You are, of course, entitled to that opinion. I was merely talking about theoretical limits and what is required to truly replace film at all levels. Like a typical DB, most people look at the new 40MP models and shrug their shoulders and consider it good enough. 12MP with a large sensor is very close to 16MP, so the 5D could blur the line from time to time. But as others have said, it's not *quite* a total replacement for film at 12MP.
I consider 2400dpi scanned to be the lower limit to replace film, since every scanner on the market does at least this with 35mm film, and most of the D-Labs also are about this resolution as well. That means a lot of data, since that 2400dpi doesn't have micro lenses, moires, anti-aliasing, or other factors affecting it. It's 2400dpi with full color at every pixel. That pushes the bar up quite a bit for digital due to the way Bayer patterning works.
Now, whether we call it 60% or 70% or 75% aside, the fact is that a Bayer sensor has to be higher resolution to replace film because of these inherent design flaws. There is some loss of information that software can't really get back fully due to the lower percentage of red and blue sensors. So you have to shoot at higher resolution and then drop it back down with software to get that smooth and clean look of good film.
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=192702\")
It is not my intention to make this a "film versus digital" thread, and you appear to have backed off on claiming that Foveon sensors are delivering three times the resolution per photosite that BFA sensors deliver. Yes, we are all entitled to our opinions and I wish I had phrased my objections to your earlier posts more diplomatically, but what I'm referring to is the experience and results that those opinions are premised upon. Here's [a href=\"http://www.bythom.com/thom.htm]someone[/url] who has a different opinion than yours about this film versus digital debate and the format and megapixels comparisons. If you ask him (send him an email), he'll tell you that 10-12 MP DX sensors do a better job than 135 format color film does -- if Michael Reichmann wants to get involved here, I'm sure he'll weigh in with a different opinion than yours about the larger format film versus digital comparison.
There's an apt expression that addresses the broader issue of pixel equivalence being discussed here: The proof of the pudding is in the eating. Now if the pudding you want to eat is black and white resolution charts (or black and white anything for that matter), then black and white film is the better choice. If you want to measure black on a 100% saturated red or blue background then I am sure that Sigma's Foveon sensors would excel at that as long as the ISO wasn't pushed too high. However, for small format color photography in the real world 10-12 MP BFA sensors (even smaller DX and APS-C sensors) are every bit as good as 135 format color film assuming you know what your doing with the files they produce.
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I think a more precise description of this thread than "pixel equivalence" is Pixel Count -vs- Pixel Quality. And regardless of the opinion of the person who deposits facts here, just raising those facts or issues in this context has provided some really useful pointers for further investigation. Now we should all chant together "Praise the mfr's for the true good that they've done, and don't spare the criticism when they weasel out some new design that panders to the quality-unconscious crowd."
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Actually I don't have a problem with "more weight" as you say, but when "more weight" is ten times more, I think it's disingenuous to call that "more weight".
[a href=\"index.php?act=findpost&pid=192715\"][{POST_SNAPBACK}][/a]
Let's be clear about some things here. When you say "500mm", you are really referring to some "equivalent" focal length based on 135 film format. The actual focal length is more like 100mm, and to be fair (which marketing hype never is) the "equivalence" should extend to aperture as well as focal length. My rough estimate is that a DX sensor enjoys a 5 stop advantage in DOF isolation over a 2/3 sensor; so the question is, how much would a 100mm f/1.4 zoom lens weigh compared to a 267mm f/11 lens?
As for the overall weight. Even ignoring that the 80-400 mounted on a D60 would give you 50% more reach than a 400mm "equivalent" P&S, off the charts more DOF isolation and high ISO performance; the actual difference in weight between the Nikon DSLR/tele-zoom combo and the Fujifilm Finepix S100FS is double (around 1882 grams compared to 968 grams; now if you can find a 200 gram P&S with a 500mm "equivalent" focal length, I would like to hear about it).
Therefore, I do not think I'm being "disingenuous" writing "more weight".
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If you don't mind I'll put that back on you with the "proof of the pudding" analogy. I have two years worth of shots with a Nikon 8800 and a Panasonic FZ50, and I've been through enough exhibitions to note that my 420mm equivalent zoom works exactly as advertised, and while I don't doubt that your big heavy 500mm zoom has more dynamic range, you're just not getting anywhere near the variety of shots when you're locked down on that tripod. Of course if you're doing mostly landscapes, you can ignore the foregoing, unless you'd want to reconsider and use a MF camera for those landscapes (to gain the extra edge you're selling so passionately).
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If you don't mind I'll put that back on you with the "proof of the pudding" analogy. I have two years worth of shots with a Nikon 8800 and a Panasonic FZ50, and I've been through enough exhibitions to note that my 420mm equivalent zoom works exactly as advertised, and while I don't doubt that your big heavy 500mm zoom has more dynamic range, you're just not getting anywhere near the variety of shots when you're locked down on that tripod. Of course if you're doing mostly landscapes, you can ignore the foregoing, unless you'd want to reconsider and use a MF camera for those landscapes (to gain the extra edge you're selling so passionately).
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=192789\")
I don't have a 500mm lens, but I do have a manual focus 300mm f/2.8 lens that I rarely use and I can testify to it's weight. On the other hand, there is just no comparing the results I get with that 450mm "equivalent" (I use it on a DX camera) to what you are getting from your 420mm "equivalent" lens on a P&S camera. It's just a fact of life that you get what you pay for, and some of that payment is weight and size. There is no way faster, longer focal length glass can be replicated with slower, shorter focal lengths used on a tiny sensor -- the creative potential of the latter is much more limited than the former, although that doesn't mean you can't get perfectly fine photographs with a smaller format sensor.
I have nothing to prove to anyone, but this discussion does become meaningless without some examples; so here's a handheld shot with the aforementioned Tokina 300/2.8 shot at f/5.6 with a D200:
(http://photos.imageevent.com/tonybeach/recentfavorites/large/_AWB1915.jpg)
I doubt the background would be as blurred using a P&S digicam.
What is notable about [a href=\"http://photos.imageevent.com/tonybeach/mypicturesfolder/april2008//2008-04-19_Montage-web.jpg]this[/url] sequence is that the images are cropped and still hold excellent detail despite being cropped. (http://photos.imageevent.com/tonybeach/mypicturesfolder/sharing//_AB14794%20100%20percent%20crop.jpg) It is also useful to note that pixels are not the only thing that matters in an image and that a camera's AF and fps capabilities also contribute to telling some stories that would otherwise not be told.
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...and you appear to have backed off on claiming that Foveon sensors are delivering three times the resolution per photosite that BFA sensors deliver.
Actually, I have never once in any post that I've made online, anywhere, claimed that the Foveon sensor wasn't flat out lying about it being 3x the sensors. It's 4.6MP, because according to the definition of a "pixel" by every other source in printing and optical history other than digital camera manufacturers marketing claims, a "pixel" is:
(Dictionary.com)
The most basic unit of an image displayed on a computer or television screen or on a printer. Pixels are generally arranged in rows and columns; a given combination among the pixels of various brightness and color values forms an image. ◇ A subpixel is one of three components of a pixel used in the representation of a color image. Each subpixel represents the contribution of a single color—red, green, or blue—to the overall color and brightness of the pixel.
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Labeling sub-pixels as the real thing has always been a *major* pet peeve of mine, since it's flat out lying. 12,000 sub-pixels arranged in a Bayer pattern isn't close to what you really need to fully replace film.
Since it's not quite as easy to convert a Bayer pattern into exact true pixels, due to the interpolation that's required, a conversion factor of about 60-65% has proven to be fairly accurate. I'm being generous at 65%, though, since a smaller sensor with tiny sub-pixels is going to take a massive hit to its ability to capture vibrant colors and deal with contrast. And few DSLRs have 1:1 ratio sensors.(do any? I honestly might have missed a model or two) Most cameras seem to be making them *smaller* lately, when they really need to get larger, if anything.(or move to a non-Bayer pattern)
See, my point wasn't about absolute resolution, but about what is required by a typical Bayer patten sensor to overcome these technical limitations and be equivalent to a 2400DPI scan of film in terms of how it looks.(which most Pros consider to be a *minimum* acceptable limit - most say it's closer to 3000dpi with good equipment and low speed film) No jaggies, no moires, no fringing... Because film doesn't have those digital artifacts to begin with. Claiming 12MP is equal to film when defects in the image are present that have to be blurred/anti-aliased out at that resolution is a bit disingenuous.
P.S. I'm not attacking you, but rather the marketing lies by the camera makers. Current technologies have serious flaws in their designs that need to be solved and their marketing hype and misinformation isn't making it any better.
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I don't have a 500mm lens, but I do have a manual focus 300mm f/2.8 lens that I rarely use and I can testify to it's weight. On the other hand, there is just no comparing the results I get with that 450mm "equivalent" (I use it on a DX camera) to what you are getting from your 420mm "equivalent" lens on a P&S camera. It's just a fact of life that you get what you pay for, and some of that payment is weight and size. There is no way faster, longer focal length glass can be replicated with slower, shorter focal lengths used on a tiny sensor -- the creative potential of the latter is much more limited than the former, although that doesn't mean you can't get perfectly fine photographs with a smaller format sensor.
I have nothing to prove to anyone, but this discussion does become meaningless without some examples; so here's a handheld shot with the aforementioned Tokina 300/2.8 shot at f/5.6 with a D200:
I doubt the background would be as blurred using a P&S digicam.
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I'm trusting I did the snip OK on the quote -- anyway here's two from Bolsa Chica - wild birds at the wetlands, using Panasonic FZ50 at 420mm "equivalent". I'm sure you can see all kinds of problems with these non-pro images, being expert as you are, but seriously, do I really need a 50-lb camera to do better than this? All I would ask for is the mfr. to do the best they can in the package size I'm using now, and they can do a *lot* better. BTW this is a two-year old camera, which apparently has been replaced with "superzoom" junk using a 1/2.33 sensor. That's progress in the 21st century.
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Claiming 12MP is equal to film when defects in the image are present that have to be blurred/anti-aliased out at that resolution is a bit disingenuous.
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It isn't a marketing claim, it's what photographers experience in real world prints. Again I cite Thom Hogan (this time directly), "But let me tell you something: all this deep ending into detail isn't particularly useful. The D2x, 5D and 1DsMarkII all outperform 35mm film...", at: [a href=\"http://www.bythom.com/d2xreview.htm]http://www.bythom.com/d2xreview.htm[/url]
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I use point & shoots, which I imagine few of you do. Since their pixel specs are usually way overrated, I wonder if there's a better way to rate them. For example, if I were to take a series of landscape pics under ideal lighting conditions, do minimal or no post processing, then make several copies of each at different sizes (say, 3072x2304, 2560x1920, 2048x1536 etc.), and view all copies at full size on screen, could I say that the True Effective Pixels is the smallest size at which I can plainly see all of the detail of the original, ignoring edge artifacts etc. added by the in-camera processing? I ask this because my highly-promoted 9mp camera appears not to have any real detail beyond about 3mp.
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My view is that more than a few compact cameras used at base ISO and in the middle of their zoom range do resolve close to as much as a DSLR of the same pixel count (I am basing this on an extended usage of my Ricoh GX100).
Since they are typically designed for users with very limited post processing skills, they tend to offer a pretty strong AA filter to prevent moire etc... which limits a little bit their pixel sharpness, plus some noise is present even at noise ISO which tends to hide some detail also.
But overall, it remains pretty close.
Regards,
Bernard
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...anyway here's two from Bolsa Chica - wild birds at the wetlands, using Panasonic FZ50 at 420mm "equivalent". I'm sure you can see all kinds of problems with these non-pro images, being expert as you are, but seriously, do I really need a 50-lb camera to do better than this?[a href=\"index.php?act=findpost&pid=193043\"][{POST_SNAPBACK}][/a]
They are fine images, but the background in the first one is cluttered and would have benefited from a shallower DOF. Now please Dale, stop exaggerating about the weight of improving upon that. I posted the weight of gear that would deliver better results, the total weight is one tenth of what you are claiming. While being half as heavy is not inconsiderable (remember that in my previous post on this that the comparisons were 1882 grams versus 968 grams), it is not even remotely ten times as much.
Here's what I routinely tell my son (and anyone else who cares to take my advice) on the topic of photography: the more effort you put into an image, the more it will distinguish itself to the viewer. In this discussion that means if you want to carry a lighter camera with a small sensor and slow lens and shoot handheld then (all other things being equal) you will have less to show for your efforts than someone who is willing to haul more gear and work harder at getting the shot.
I am sorry you are disappointed with camera makers not making better P&S cameras. Many photographers share your frustration. However, many photographers want bigger sensors and faster wide angle, fixed focal length lenses with a simple UI and the ability to shoot RAW; while many consumers prefer a more telephoto image (they want the camera to get them closer to the subject) in a small package and they want it to come out of the camera ready to view, which means they end up with a "superzoom" lens and a less capable smaller sensor in a camera that doesn't shoot RAW. Since the camera makers are all chasing after consumers we end up with the latter and not the former in the P&S digicams they are marketing.
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I can't even quote Tony because of the endless repetition of "justifications" for the way things are. Well, Tony, I and my cameras are the way things are, and no offense intended, but I'm not concerned about your gear and how you use it. I've been at this since the 1960's so I'm well aware of the way things are for you. And LL shows me all the other formats as well. What I want is forward progress in my interests, and the best way you could help is to stop excusing the mfr's and just tell it like it is - they're pandering not progressing in most cases. And not only are those good images I posted, but thanks to my lightweight kit, I was able to share hundreds of those with other photogs at the wetlands using the Libretto computer I also carried. And not one other photog ever showed me anything - they were all bogged down with "camera gear". So what's the point of this "hobby" if you can't share? I know - this forum, away from the action. Well, it's a poor substitute for that purpose.
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One last point on the subject of "having less to show because of smaller less capable gear": I totally disagree - I have far more good images to show than the Big Gear folks from Bolsa, for what should be obvious reasons - I get anound the site much better, get into smaller spaces, get closer to the animals (scare them less), have no issues of tiring out, and on it goes. You probably can't appreciate that if it's outside of your experience.
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One last point on the subject of "having less to show because of smaller less capable gear": I totally disagree - I have far more good images to show than the Big Gear folks from Bolsa, for what should be obvious reasons - I get anound the site much better, get into smaller spaces, get closer to the animals (scare them less), have no issues of tiring out, and on it goes. You probably can't appreciate that if it's outside of your experience.
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First, on "justification"; I am not justifying anything -- it's just a fact that camera manufacturers are more interested in "pandering" to consumers than making a camera that you want. I don't like it anymore than you do and I'm sorry that you are upset by this state of affairs.
Second, if you are going to quote me, then do me the courtesy of accurately quoting me. I said "...(all other things being equal) you will have less to show for your efforts than someone who is willing to haul more gear and work harder at getting the shot." That means they have to work harder; now if you worked harder then you got the better images, and I acknowledged that I thought you got fine images.
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Two points: We're here to provide useful info - not to state the obvious, or say "that's the way it is" etc. When there's no other reason to state those things -- it defaults to justification. Point two: I didn't work harder to get my pics, I worked *less* because I had better (i.e. more appropriate gear).
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It isn't a marketing claim, it's what photographers experience in real world prints. Again I cite Thom Hogan (this time directly), "But let me tell you something: all this deep ending into detail isn't particularly useful. The D2x, 5D and 1DsMarkII all outperform 35mm film...", at: http://www.bythom.com/d2xreview.htm (http://www.bythom.com/d2xreview.htm)
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That's one sentence in the whole review, and is quite obviously his opinion. I don't see him giving hard facts about it. 12MP to compete with a 35mm scan at 2400dpi would require about a 75% ratio for interpolation and that's just not physically possible beased upon how the technology works.(66% is the most you can get, actually, out of the raw, which is why 65% is being very generous. As is 2400DPI. If you bump it to 3000dpi, it jumps to nearly 13 million actual full pixels, which the Bayer patterned sensor isn't possibly going to do - that's over 100% radio. Some desktop scanners go to 3600 DPI even.(though I think 3000 is about the practical limit - and is what the Minolta scanners do)
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That's one sentence in the whole review, and is quite obviously his opinion. I don't see him giving hard facts about it.
Some desktop scanners go to 3600 DPI even.(though I think 3000 is about the practical limit - and is what the Minolta scanners do)
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In theory I could devise a scanner that could deliver 50 or a 100 MPs from a 35mm negative or slide; but that doesn't mean there is that much meaningful detail in that negative or slide. The question that needs to be answered (and may have an actual connection to this thread) is how many pixels can you really extract from a 35mm negative or slide? Not addressing that question and the lack of side by side examples makes your arguments unsubstantiated speculation.
You can choose to disbelieve Thom Hogan on this issue; but then you are saying he is either wrong or lying. It is specious of you to try to claim simultaneously that Thom may not have really meant what I quoted (because it is only one sentence in a longer review) and to then argue that is just his opinion. Thom's "opinion" is based on his experience, and I trust his experience and mine over your speculations.
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Most experts agree that the effective maximum for film is between 2400 and 3000DPI. Certainly not less than 2400DPI for good film. Even the cheapest DLabs try to keep it at or near 2400DPI. That raises the bar to slightly higher than 12MP with a Bayer sensor.
Again, if we were talking about 16MP, I'd say it was a wash, or close to it, though with AA filters and other nonsense being so common, you might have to go to 20MP or so or find a camera without such a filter.
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Most experts agree that the effective maximum for film is between 2400 and 3000DPI. Certainly not less than 2400DPI for good film. Even the cheapest DLabs try to keep it at or near 2400DPI. That raises the bar to slightly higher than 12MP with a Bayer sensor.
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My D300 has 12.2 MPs. Anyway, just show a comparison of a scanned slide side by side with a 12 MP DSLR file -- if the shots are taken under identical conditions then that would put the debate to rest.
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Two things: One, some small cameras shoot RAW (Pana FZ50 for example), and I use it, and it makes a real difference, and when you consider that the *only* reason the mfr's leave it out on some advanced P&S models is due to their cynical view that naive users will ask too many questions, well that's really pathetic. Item 2: I've developed my own B&W for years, used "zone system" to some extent, have even produced apparent "grain-free" 11x14's from Minox 9mm. My observation of low-ISO color slides and prints from Leica M cameras is they look different from digital unless both film and digital output are viewed at reduced size or sufficient distance to make the underlying structure invisible. My experience in making fixes to digital images tells me there's a subconscious threshold factor, so viewing for film -vs- digital to obscure the grain etc. would have to take place at 4x or more reductions from maximum image size, otherwise your brain would still see the differences.
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My observation of low-ISO color slides and prints from Leica M cameras is they look different from digital unless both film and digital output are viewed at reduced size or sufficient distance to make the underlying structure invisible. My experience in making fixes to digital images tells me there's a subconscious threshold factor, so viewing for film -vs- digital to obscure the grain etc. would have to take place at 4x or more reductions from maximum image size, otherwise your brain would still see the differences.
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You compared the color slides to which digital camera's files? Did you use the same lens in the comparison? How do you know you weren't comparing lenses and processing rather than digital compared to film? That's why Thom Hogan's experience carries more weight with me here; he uses the same lenses (Nikkors) in his comparisons, he is also very knowledgeable about post processing.
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I would expect after 30-plus years of film and 15-plus years of digital processing, with the highly exacting work I've described, you might assume I can tell the difference between grain, pixellation and noise, and lens crud (to use a crude term), but apparently that's not the case. Maybe I should have taken up knitting?
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I would expect after 30-plus years of film and 15-plus years of digital processing, with the highly exacting work I've described, you might assume I can tell the difference between grain, pixellation and noise, and lens crud (to use a crude term), but apparently that's not the case. Maybe I should have taken up knitting?
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Maybe you could just specify what camera and lens you are comparing the film and Leica lenses to. Better still, you can also show examples so we can make direct comparisons for ourselves. For now (considering what you have written so far in this thread) I wonder if you are comparing a P&S digicam to a Leica, and that would be a ludicrous comparison and would tell us nothing.
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My main point in posting is to help people, who might then help me. But nothing I do will help you, in spite of all my experience and wealth (of knowledge, funds, and equipment). I hope your trust in Thom pays off - he seems like a better than average pundit as pundits go, but I doubt he has anywhere near the depth I have.
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Addendum: I've put my negatives and slides under a Wilde microscope for inspection - if you've seen such a thing you won't forget what grain looks like. I don't have a slide scanner but: 1) I could buy one just to supply a pic and impress Tony, or 2) If I did that, would the scan be a true representation of the film grain? I dunno - haven't tried, don't really care.
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I hope your trust in Thom pays off - he seems like a better than average pundit as pundits go, but I doubt he has anywhere near the depth I have.
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He has one thing on you in spades -- humility. I become immediately suspicious of arrogant postings claiming a wealth of expertise from someone with no website, no biography, and whose only bona fides are a couple of mediocre bird shots.
Now lets see how this "Ignore User" feature works" -- bye.
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Now I remember Tony - the professional skeptic. The skeptics' rules: Admit nothing. Deny everything. When cornered, demand proof, then refuse to accept it. Now my feelings are hurt Tony. Please come back.
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The biggest problem with Foveon sensors is that they get noisy at relatively modest ISOs; which is another way that my D300 kicks butt on both Sigma DSLRs and film.
Hmmm... that's not what I've found. I picked up a Pentax K20D, a 14MP camera that will do as good or better than a D300, because I wanted something 'better' than my Sigma SD14 in terms of resolution and camera functionality. In short, I wanted a dSLR that would not have the limitations of the SD14.
The K20D is a pretty amazing camera, and because it will also take M42 lenses, I can shoot the same scene with the same lens with both the SD14 and the K20D. What have I found?
I've found that the SD14 is VERY competitive with the K20D in terms of actual resolved detail and image quality. In fact, I'd give the nod to the SD14. Where the K20D excels is in better/faster AF, in-camera image stabilization (handheld shots with a 300mm lens at low shutter speeds are very sharp), and multiple shot capabilities (for bracketing and capturing action). With the latest firmware the SD14 is excellent at ISO 200 and below, very good at ISO 400, and acceptable at ISO 800, while the K20D is excellent at ISO 400 and below, very good at ISO 800, and acceptable at ISO 1600. In other words, you get one extra stop of 'film' speed.
I'd characterize the SD14 as my 'Kodachrome/Velvia' camera... sort of like a medium format manual focus/exposure camera. When I can take the time to think about a picture, the SD14 allows me to obtain superlative results in terms of color and resolution. The K20D is more of a 'chromogenic' camera in that I can get good results while having more latitude with exposure. Pixel for pixel (shooting a 100mm lens on the SD14 and a 50mm lens on the K20D, and cropping the same # of pixels out of the center of the K20D image), the SD14 is sharper.
My plan for the K20D is for 'action' type photography, like air shows, sports, etc. I'll continue to use my SD14 for landscapes, scenics, etc., or anywhere where I can be more deliberative. When I take the time to make a 2x2 multi-row panorama, the resulting 14 MP SD14 image blows any other dSLR away, not excepting the high-end Canons.
BTW, I think the SD14/K20D combo is worth considering. Both cameras can share the same batteries, use the same (M42) lenses, etc. And, I also think that Sigma and Pentax have both done a good job of putting forth the qualities (and implicitly, for Sigma, the limitations) of their respective products.
An example of the same subject with two different cameras:
Pentax K20D:
(http://obijohn.smugmug.com/photos/385461823_k77Q8-X3.jpg)
Sigma SD14:
(http://obijohn.smugmug.com/photos/385278697_V8HsH-X3.jpg)
Which one do you like better?
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After adjusting the darker image, the leaves looked about the same, but the darker background detail was pretty well lost.