I made a post on a forum recently that relates to the discussion we had here. I hope you don’t mind if I link it:

http://photography-on-the.net/forum/showthread.php?t=706255

Kind regards,
–Daniel

Just kidding. I’m glad you’re out of the confusion.

i guess that’s why the whole thing was so puzzling to me. these focus points just popped out one day on a few images and then the very next set of images (as well as many many others), it didn’t have them.

it’s very bizarre. the problem somehow reside with the images because they got transferred from compactflash card to PC and then back over to the card and they show up on the LCD screen again but yet they don’t show up on my PC. go figure.

what’s the best way for me to get a video file to you?

The problem is that I’ve gotten a few images where when I’m reviewing the image on the LCD screen, some of the red autofocus points show up in the image (lit up). I know this sounds weird but the points don’t actually show up in the image itself. The problem happens sporadically. Maybe some of the circuitry gets too hot internally? Not sure. Maybe it’s the LCD screen? But it remains there when I review them on the screen. That’s all I can say. When it first happened, I was going to print it out or email them to Canon to show what’s happening but it’s not something that’s permanent on the image (thank god!). So there’s no way for me to demonstrate what’s going on.

Anyone else experience this????????

It is hard to say what exactly happened in your case. You mention you were working inside a church, and I’m assuming that it was a reasonably dark place. the 5D Mark II can’t focus fast and accurately in dark situations. It appears that even in good light, it still has issues and can often make your pictures appear out of focus. I suggest you read the full posts in the links below and do some tests with your 5D Mark II in various lighting conditions before you take it on another job. Many people are having problems as you will see. Read the following links:

http://blog.kareldonk.com/canon-eos-5d-mark-ii-barely-worth-it/
http://blog.kareldonk.com/canon-eos-5d-mark-ii-not-worth-it-save-your-money/

Thanks for expressing your point of view about the Canon 5D Mark II. I have been using this camera for a month for landscape and people photography. Based on my experience, I agree with you on the poor design of the AF system of this camera. To achieve selective focus, most of the times I have to recompose the frame. But this is Okay for me in landscape photography. In people photography, however, I have missed more than 10 shots in different occasions. What has happened is that the camera has failed to focus. I don’t remember what focusing point I was using, most likely the one in the center, but in one occasion I took a shot (and the AF worked well) and immediately after I recomposed the image to take another picture of the same subject but the AF failed. The AF system was completely dead (the red square did not light on). And this was not because the camera was busy writing the file to the card. This problem has occurred only indoor (one inside a church) with either the 70-200 mm f/2.8 IS lens or the 16-35 mm f2.8 II lens. My question to you is: do you think that the cause of this problem can be explained by the poor AF system of the camera? I found your site looking for the cause of this problem.

Sorry I didn’t see your message earlier. My e-mail address is my initials @kavod.com.

> One question I have Daniel, and something that your claims depend on,
> is how do you know you will get better image quality by downsampling a
> large image to a smaller one?

Practical experience backed up by sampling theory and experimentation.

> I thought I heard that if everything else
> is equal, a 40MP image downsampled to 10MP will be inferior to an image
> that was captured natively at 10MP. Is this a debatable issue or there
> consent about it one way or the other?

There is consent among everyone who has practical experience in the area, understands the theory, or has carried out experimental verification correctly.

> Just found something that seems to answer those questions. According
> to the article, downsampling doesn’t work as well as it could in
> theory because noise is larger than 1 pixel in most cameras. Would
> like to hear your arguments to this Daniel.
> http://blog.dpreview.com/editorial/2008/11/downsampling-to.html

In one of my posts above I linked to a thorough rebuttal of exactly that blog post:
http://forums.dpreview.com/forums/read.asp?forum=1018&message=30190836

Phil has a great web site, it’s very useful and I like it a lot. But he makes mistakes about some things and this is one of them.

Second, reading you and Daniel’s back and forth I think you’re missing some of his logic. I don’t have technical knowledge of noise, interpolation, or any of that stuff, but Daniel’s hypothetical camera examples are logical and your responses have either ignored his logic or haven’t been logical. I’m not saying you’re wrong Karel, but just that you haven’t adequately responded to what Daniel is trying to say.
One question I have Daniel, and something that your claims depend on, is how do you know you will get better image quality by downsampling a large image to a smaller one? I thought I heard that if everything else is equal, a 40MP image downsampled to 10MP will be inferior to an image that was captured natively at 10MP. Is this a debatable issue or there consent about it one way or the other?
Also, if what you are saying about downsampling is true, and you get higher quality by downsampling a larger image, wouldn’t there be diminishing returns with the downsampling? With your 99D you say, “all of them [print sizes] would [be] tens or hundreds of times better than the 40D.” But I would think that as long as you are printing at a consistent dpi and as long as the 40D is not upsampling, that with a small enough print it would be either impossible to make the image better or insignificant. For example, using your idea of the 99D with 9999 MP, what if you had another camera that was 500 MP? If you printed 4×6 prints at 300 dpi I would think that there would be no difference in image quality or if there was any it would be insignificant. From my logic, it wouldn’t be until much larger print sizes or much finer dpi that any difference would become apparent.

first, I’m not fond of your writting. your attitude makes me want to not read the article.

ps: spell check will catch some of your spelling errors.

In real life, you choose the best camera for the job. That’s it. There’s no law that says you can’t use a certain camera for a certain job just because it has more pixels. So if it’s legal to use the 50D for the same purpose (print size) as the 40D, the results are the quality is the same. The 50D also can be used for *other* jobs, with even *more* resolution than the 40D, but the 40D doesn’t have that resolution anyway, so it doesn’t need comparison.

Again, if the 99D (with 10 gigapixels) from my example above was released tomorrow, you could make wall-sized prints, mural size prints, 20×30 inch prints, 12×18, etc, and all of them would tens or hundreds of times better than the 40D.

It’s only the football-field sized prints that would be worse than the 40D. And 100% crops would look worse than the 40D.

You’re saying more megapixels are not for resizing, but to do larger prints. According to that logic, the 99D *must* be used for football-field prints. (Personally, I would be happy with 15 feet by 10 feet at 300 DPI at the most.)

The photographer does not *have* to change his output size just because the manufacturer added more pixels. He may still continue using his desired output size and getting similar results to the equipment he uses now, and, if desired, use the higher resolutions.

> Also the 50D does not have much more resolution compared to the 40D.
> If anything, the 50D images look less detailed. Check the DPReview
> review of the 50D and look at the images. So more noise + less detail,
> even though the resolution went from 10MP to 15MP. That’s a step
> backwards.

DPR is a great web site, and I like it, but some of the methods are flawed. The 50D review, specifically, has been thoroughly debunked. Here’s one such correction:

http://forums.dpreview.com/forums/read.asp?forum=1000&message=30412083