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Messages - V8Beast

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So if we make our interpretation a bit more conservative, DXO is claiming the D800 somehow magically gains around some 7500-8000 discrete tonal levels (or luminance levels) by the simple act of DOWNSAMPLING (as they claim, anyway)? Fishy. And even if that WAS somehow possible, whatever you "gain" is artificial...the camera itself is still the limiting factor when you press the shutter button and capture a scene, in which case the D800, according to DXO's "screen DR" results, captures somewhere around 13.8 stops of DR.

If I understand correctly, DxO claims an increase in DR by the simple act of downsampling an image? This would seem to favor big MP cameras, and I question the legitimacy of the subsequent results.

From a standardized testing procedure, I fully understand that they downsample to level the playing field between sensors of different resolutions. On the other hand, I can't possibly see how this scenario applies to actual shooting technique in real life. Obviously, if you buy a 36 megapixel camera, part of the appeal is the massive resolution. I can't see why you'd pay money for all those pixels, just to downsample an image and throw them away. However, this is precisely the scenario that DxO is simulating, is it not?

EOS Bodies / Re: Canon smarter than we think
« on: March 29, 2012, 01:34:33 PM »
Like many other, I also with the 5DIII were priced closer to $3,000 than $3,500, but at the end of the day, I was more than willing to cough up the extra dough for its substantial improvements in AF, FPS, and build quality.

That said, I don't think Canon has showed all its cards just yet. There's been talk of an entry-level FF body for quite some time, and if it turns out to be true, the 5DIII's price point makes more sense. The fate of the 7D line is unknown at this point, either, so if Canon does axe the 7D or merge it into the xxD line, then an entry-level FF body priced somewhere between the 7D and the 5DIII makes even more sense.

@V8Beast: I guess my point got lost in all the rest. 

I wouldn't say that. I just found your assessment that 90 percent of observers wouldn't be able to tell the difference between the two posted images to be quite bold :) That said, my test subjects weren't exactly your typical observers. I'd say that their eyes are well trained :) It's quite possible that if presented the two images in question, the general public would have a much more difficult time distinguishing any differences between them.

I wouldn't recommend using their numbers as a sole source of information, though...they DO tend to be rather odd at times. ;)

That's the point that seems to get lost in all the e-hysteria. The DxO stuff is useful at times, but some people seem to think it' s the be all, end all authority for judging image quality. How can you possibly attempt to objectively judge a medium (photography) that's so inherently subjective? You don't need a lab test to determine whether or not you like the images a camera produces. 

I think this is right here demonstrates exactly why DXO has something to offer. Your opinion here is simply that...your opinion. If you actually held a poll about those two photographs, I would be willing to bet that you would NOT get a 90%/10% ratio, where most people could tell just by looking at those photographs which was which. I would bet such a poll would end up closer to a 60%/40% ratio.

It's interesting how different people see the same set of images differently. It's funny that you bring up a "poll," because I did just that after these shots were taken. I sent these two images out to a half-dozen colleagues of mine to see if they were able to determine which image came from each camera. Every single one of them correctly identified which shot came from which body, and unanimously agreed that the image shot with the 5D looked substantially better. Keep in mind theses are professional automotive photographers, each with decades of experience, that routinely scrutinize images like this. So you're right. The ratio wasn't 90/10. It was more like 100% of respondents that agreed with my assessment :)

In fairness, viewing shrunk down images on a message board do hide some of the obvious differences. If you're really bored, I'd be happy to email you both jpegs, but I ain't sending the damn raws :)

On a somewhat related note, clients generally have no idea what kind of equipment their contributors shoot with. All they know is the quality of the images you submit. That said, my editor immediately complained about how the images shot with the 7D lacked contrast and shadow detail with blown-out highlights. This despite my best efforts to address these issues in post. 

That wouldn't be entirely because how each of us sees is subjective, but also due to the differences in computer screens, computer screen calibrations, etc. To me, those photos look relatively similar, however I have a calibrated screen tuned for post-processing photographs for final print. Because I print and judge my print qualities from how things look on-screen, the blacks in those photos look pretty even-keel. I'd be willing to bet, however, that one of them would indeed stand out as having "better" blacks if I viewed it with the screens I have at work, as they are calibrated for an entirely different purpose, and are a bit lower contrast (which would enhance shadow details.)

The difference is obvious on a $h!tty monitor as well :)

There is also the simple point that we don't know for sure how dark the deepest shadows are in the leaves of the trees of the 5DC shot. They may look "better" simply because they are not nearly as deep as the ones the 7D had to work with. That may be the case with all the 5DC shadows, where as the 7D may have had to deal with deeper shadows everywhere. You can't really make an objective comparison with two entirely different shots like don't know for sure exactly how the shadows of each shot compare. You need a consistent, calibrated photographic source to properly measure the differences (even if they are "useless differences"), and that would be an area where DXO excels.

You make a good point. This is by no means a scientific test, and it would never stand up in a lab. However, it was never meant to be a scientific test. It just so turns out I had a a car to shoot, my 5D took a dump, so I busted out the 7D as a backup, using it in the same manner with the same technique in which I always shoot. You can question the difference in background lighting in the foliage between the two shots, but you weren't there :) All I can tell you is that, in terms of the backgrounds, the image captured with the 5D looks MUCH more like what I saw through the viewfinder that the image captured with the 7D. There were all kinds of beautifully backlit green pine needles in the 7D's viewfinder, but none of that showed up in the captured image. 

DXO mark publishes low-level measurements run through a standard set of mathematical formulas. While their numbers may seem odd, I find them valuable at times if for no other purpose than to demonstrate that physical hardware specifications make a picture not. The best example are DXO's MF camera ratings, which generally appear rather crummy compared to the latest and greatest from Sony, Nikon, and Canon. Empirically, modern-day digital MF sucks (regardless of niche.) Practically, they are still the best money can buy (by a long shot) for the niches they service.

I'm not saying this to be a smart@ss, but have you shot with multiple bodies at length in order to asses how DxOMark's ratings stand up to your own personal observations? I find that sometimes their rankings seem legit, while at others they're completely off. For instance, I shot with a 20D for a long time before moving up to a 5D. The IQ of the 7D reminded me a lot of the 20D, and sure enough, both bodies rank similarly on DxOMark ratings. I'd say their rankings of the 5D, 1DII, 1DsII, and 1DsIII seem somewhat useful when compared to my personal experiences with those bodies as well.  That said, according to DxO the 20D and 7D aren't that far off IQ wise compared to the 5D, but I'd beg to differ. Your results may vary :)

EOS Bodies / Re: DXO vs Reality
« on: March 28, 2012, 07:52:09 PM »
I received feedback from a client today who wasn't too thrilled with my work. He commented on how the images were poorly lit and composed, and lacked any emotion. Fortunately, I was able to manipulate the exif data to make it appear as if the images were shot with a D800. I sent him a link to its DxOMark test results, explaining how it has the best-performing sensor on earth. He then said, "you're right, these image right here are some medium format $**t. Now everyone's happy ;D

Go to a club with the 5DIII one night, and a D800 another night, and see which one gets you more women. Be sure to take lots of sample images.

Are you related to wickidWombat  ;) ;) ;)

Why yes, I do believe my ancestors inter-bred with wombats some time ago. This would explain why the ladies think I'm so cute and cuddly.

As for CR board member wickidwombay, I presume he might take offense to the notion that he might be related to a hack like me :)

EOS Bodies / Re: Ken Rockwell Updated 5D MK3 Review
« on: March 28, 2012, 05:24:18 PM »
It's hard to take a man seriously who posts snapshots taken with $5,000 worth of gear.
Actually, $3600 worth of gear...his sample photos use a 50mm f/1.8 on the front of the camera. Kind of hard to believe he doesn't have a better prime in his bag...or that his D800 review will use the Nikon 50mm f/1.8

My bad. For some reason I assumed it was the 50mm f/1.2L. You'd think that someone that spent $3,500 on a body would use something other than a $100 lens in front of it. 

Here are two samples images of black cars, one shot with a 5DC and the other with a 7D. Both images were taken with the same 70-200 f/4L, on bright sunny days, within 45 minutes of sunset. So the variables in light quality and lens quality is next to zero. Both images are out-of-camera raws converted to jpegs with no post processing.

According to DxOMark, the 7D has 11.7 stops of DR, while the 5DC has 11.1 stops. Call me crazy, but the the 5D seems to pull out substantially greater shadow detail, especially in the foliage. IMHO, the difference is so obvious I don't even have to label which image came from the 5D, and which came from the 7D. I very much prefer the color and contrast of the 5D's images, but again according to DxOMark, the overall sensor scores between both bodies is very similar (66 vs. 71).

Go to a club with the 5DIII one night, and a D800 another night, and see which one gets you more women. Be sure to take lots of sample images.

Personally I am not convinced about the DxO measurements - they dont pass the common sense tests

I'm of the same opinion, but I figure that if so many people think they're the holy grail of judging IQ, there must be something to it. I'd like to try to understand it better before making any further judgements concerning its usefulness.

EOS Bodies / Re: Ken Rockwell Updated 5D MK3 Review
« on: March 28, 2012, 04:01:37 PM »
Why don't you start writing reviews by your own, Neuro? Seriously. I find your comments very useful.

Off topic, but that's one heck of a portfolio you have there. Great work!

We have heard that the D800 has wonderful metering must take the shots in green square mode  ;D ;D ;D

Who needs green square mode? I heard you can run a USB cable from the 5DIII into your ear, and it will compose, frame, and meter your shots telepathically :)

Yes absolutely more DR means a greater amount of perceptible detail from the shadows (noise floor) to the highlights (clipping headroom). You won't crush your blacks (lose shadow detail and/or have perceptible sensor noise) or blow out your highlights (e.g. lose the clouds in the sky) when you have more DR. And shooting RAW with lots of DR, exposure settings aren't as critical as a result, you will retain detail even with relatively poor metering.

That's what I figured. My next question is if the DR difference should be noticeable in out-of-camera raws, or do you have to manipulate the files in post production to maximize the DR? It's a dumb question in some respects, but I believe the 7D has better DR than a 5DC according to DxOMark, yet I've noticed that with dark subjects, the 5DC will capture detail in the clouds while they'll get blown out with the 7D. The highlights seem more difficult to recover with the 7D as well despite it's superior DR. Maybe I'm just doing something wrong :)

The D800's photocells look to have very similar DR to the 5D3's, but the D800 has packed them more densely, and DR improves when reducing resolution, so the D800's advantage in MP will be felt in the noise performance of an uncropped but reduced resolution output. So if you are delivering 8MP JPEGs from RAW originals with the same per-pixel DR, the 36MP original will have better delivered performance than the 22MP one. At least that is how I understand the theory there.

I know it's an apples to oranges comparison, but does this mean that the D800's DR advantage is most obvious when its resolution is reduced to the same level as the 5DIII? I can see why you'd downsize the resolution if you're DxO to level the playing field with sensors of different resolutions, but I can't see doing this in real life. A massive part of the D800's appeal is its resolution and DR, so I can't see why you'd pay for a 36 megapixel sensor only to throw those pixels away.

I've tried to comprehend the DxOMark test standards the best I can, but apparently I'm not the smartest person out there. When I think about the practical advantages of greater DR, I envision that it would enable me to recover burned out highlights, or pull out more shadow detail, out of a  high-contrast scene.

For instance, I have no idea how many stops of DR is captured in this image. What I'd like to know is if having 14.4 stops of DR instead of 11.9 would allow me to pull more shadow detail out of the wheels, body panels, and asphalt on the shadow side of the car. I'd like to think so, since the highlights on the hood/grille compared to the wheels/asphalt seems to have maxed out the DR of the 5DC's sensor.

EOS Bodies / Re: Ken Rockwell Updated 5D MK3 Review
« on: March 28, 2012, 02:52:27 PM »
It's hard to take a man seriously who posts snapshots taken with $5,000 worth of gear.

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