Another in a long line of posts that I write, make it a draft so I can do one final edit, then forget about it for over a week.
I guess I am not alone in realizing that the new Canon 5D Mark II opens up some opportunities to snap up the 5D Mark I for a good price. In fact, a lot of people realized that the price of the 5D and 50D are very similar and there's a lot of debate about which is better. As you probably know, I would prefer the 5D.
Bob Atkins (bio), a very knowledgeable person in all things EOS, has an interesting post about the 50D vs 5D debate. Go ahead and read it. Yeah, really, I mean read it. Even if you shoot Nikon or some other camera than Canon, give it a quick read. There's some bigger issues discussed here than just camera models.
Ok, are you back yet?
So, I take no issue with his first point.
In fact, I think it is important for all photographers to realize that diffraction reduces sharpness at smaller apertures. I knew this somewhere in my head, but I also distinctly remember wondering a few months ago why my images at f/22 weren't as sharp as I hoped they'd be. Put simply, after f/16 or so, expect sharpness to decrease as you stop down. This happens for all cameras from all makers. Bob also has a good point about the trade-off between spherical aberration and diffraction and the basic 'sweet spot' of any lens.
On the second point I have to cry 'Bad Science!'.
Yes, I get his point; the 50D's 15.1 MP is better than the 40D's 10.1 MP and this difference shows up even with crappy lenses. If you can call the kit lens 'crappy'. Actually, the kit lens isn't that bad, which many have been saying all along.
My main issue with Bob's comparison is that the experimental evidence suggests that APS-C resolution peaks at around 12 MP (again, see my previous post for details). Honestly, I suspect it might be somewhere between 12 - 15 MP, but the point remains... of course the 10.1 MP sensor in the 40D is outresolved by the 50D!
Also, I have to say the evidence Bob provided was less than compelling -- the JPEG artifacts in those images were more noticeable than the resolution differences. I consider my eyes pretty good, but I was hard-pressed to see a big difference in those images. And for that reason, the other factors, like the cost and improved screen, would be more important to me than the extra resolution when deciding between the 40D and 50D.
Ok, maybe my cry of 'Bad Science!' was a little premature. I do see Bob's point. He's mostly poking holes in other peoples' arguments that the 50D has no increase in resolution over the 50D. And he does demonstrate that there is a meaningful difference in picture quality between the 40D and 50D even on the kit lens. It sounds like he is taking aim at those people who are trying to compare 100% crops between the cameras -- of course the 100% crop of a 15 MP camera will be less 'sharp' than a 100% crop of a 12 MP camera. I fully agree -- pixel peeping is not what makes a camera useful.
I still really wish Bob had posted some better images though. It might even be cool to see the difference on an "L" lens between those two cameras. It'd also be really interesting to see the difference between a 12 MP sensor and the 15 MP sensor, if that's possible.
Ultimately, I think we are splitting hairs on this 40D vs 50D comparison. If you have the cash, buy the 50D. If you don't, buy the 40D. If you are somewhere in between, compare the features (I'd consider the 50D more of a 13 MP camera than a 15 MP though) and make an educated decision.
Then focus on your pictures.
After all, a picture of a turd is still a picture of a turd whether it is captured in 10.1 MP or 15.1 MP!
A little addendum to this post which is (somewhat) related.
Turns out, the 5D Mark I isn't the least expensive full frame camera on the used market.
The Canon 1Ds is.
On eBay, the 11 MP 1Ds prices have dipped below $900 while the 12.8 MP 5D is still scratching $1000. A local craigslist ad had a 1Ds for $950, well below used 5D prices.
Sadly, there's a reason you can pick up a used 1Ds for less than a used 5D. The 1Ds is from the previous generation than the 5D Mark I, meaning worse noise performance and a reputation as a very large, heavy brick. On the plus side though, it is full frame and it is a 'professional' camera, meaning weather sealing and an intimidating presence.
For more, check out:
- Photo.net thread: 100% crops comparing the two cameras. Not a huge difference visible.
- Sportshooter thread: Echos most of what I've seen on the web -- the 1Ds has significantly worse low noise performance, a slow and hard to use interface, and weighs a ton.
But I'm still left wanting the 5D to have it both ways: full frame AND low noise performance!