TEST FOR 5D + LENS 24-70USM F2.8

[peter_k6]

<p>

<p>Hi I am just about to receive Canon 5d and Canon lens 24-70mm usm f 2.8 which i both from the second hand in excellent cond. as it was described I heard a lots of good things about this setup. I have had canon rebel xt until now. Can anyone give me some advice what is the best way to check up if body is good "sensor" and also lens? What would be the best check up steps? Thank you</p>

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[images_in_light_north_west]

<p>Just get out and shoot, maybe use a tripod and MLU with timer or remote to see if you have a good sharp copy of your 24-70. You should have no problems with the 5D, if you do they should be apperant.<br>

Ross</p>

[JDMvW]

<p>You will need to go out and photograph lots of brick walls straight on, and check your lens carefully for back-focus problems and unsharpness. You can test the shutter by tripping it until the unit self destructs -- that way, if you keep count, you'll be able to see if it lives up to its 100,000 actuation standard.</p>

<p>Or, you could just go out and use the camera and lens together, shooting RAW+fine jpeg, and see if it does the job for you.</p>

<p>I just bought a used 5D, with a 24-105mm lens in my case. I haven't yet got it above a couple of hundred actuations, but I'm working on it. ;)</p>

<p>I really love the 5D MkII, it has lowered the 5D prices and made many 5D mkIs available. ;)</p>

[sarah_fox]

<p>Oh, come on now... It's used equipment. It only makes sense to test it. ;-)</p>

<p>Testing the sensor: Aim at a white wall, lens WAAAY out of focus, smallest aperture. Take a shot with the wall exposed at a medium-ish gray, and open it up for examination. You might boost the contrast a bit. You'll probably see some sensor dust. That's normal and means it needs cleaning. What you don't want to see is any scratches, which are admittedly rare. Next, repeat the test with a very long exposure (maybe 5 or 10 sec), probably in dim light. This will give you a glimpse into how many hot/stuck/dead pixels you might have. (All cameras have them. You just don't want too many.)</p>

<p>Testing the lens: Unfold a newspaper, and photograph it. You'll be able to examine both the sharpness of the print and the amount of chromatic aberration (purple fringing) throughout the frame. The image quality won't be as good at f/2.8 as at perhaps f/5.6 or f/8 (where it should probably be at or near its best). Above f/16, the image will start to get fuzzy again, due to diffraction (a physical phenomenon that plagues all lenses). Compare your results with the test results on <a href="http://www.slrgear.com">www.slrgear.com</a>.</p>

<p>If your used equipment is like the used equipment I've bought, everything should work just fine. Be happy, go out, and enjoy some full frame digital photography! It's a blast! :-)</p>

<p>Oh, and congratulations to both you and JDM on your new acquisitions! :-)</p>

[DickArnold]

<p>I recently bought a Canon refurb 5D and I knew within about fifty frames and few prints that the camera was fine. The colors, contrast and sharpness are impressive IMO. I love the mark II for the same reason. JDM this is the third thread in a row where I have agreed with you. </p>

[JDMvW]

<p>I didn't say not to test it, but I'm convinced that the best test is to use it and see if it works. If there are serious focus or other problems, they should show up in such practical testing without brick walls and newspaper print.<br>

I'm afraid that the latter encourage the sort of "OMG is my lens unsharp in the corners?, PANIC!" things that are posted nearly every week on all the forums. ;)<br>

Thanks for the congratulations. I blame it all on my 35mm PC-Nikkor. It was the reason I went Nikon back in 1971, and now it <em>forced</em> me to go "full frame" against my otherwise preference for the 50D.</p>

[sarah_fox]

<p>JDM, I agree that not everyone knows what reasonably to expect in testing. On the other hand, casual picture taking doesn't necessarily show up the problems.</p>

<p>I think you're really going to like full frame digital. When I bought my 10D, I really wished I had full frame (but of course couldn't afford any such thing). My 5D was a breath of fresh air, as my field of view opened up greatly with my collection of wides. I'll probably wait until Canon has a good solution for suppression of banding and/or advances much further in ISO capabilities before I upgrade again. Who knows? Maybe the economy will be so far down the toilet that I can pick up a 1DsIII in a garage sale for $100 in a few years. ;-)</p>

 

[JDMvW]

<p>Point taken. Testing is good if you realize that all lenses are compromises and compare them fairly, not against some impossible ideal. If you test, I should think it a good idea to compare the results to places like photozone.de (for 15x22mm sensors) or other sites for 24x36mm sensor use. As my sainted mother used to say, "CA happens".<br>

Yes, I already quite like the 5D. I got it together with the 24-105mm IS L and a 430EX. The former seems almost exactly to fill the 17-85mm IS slot for the full-frame.<br>

I haven't had a flash in years that I had used (still have all my old Sunpaks and Rollei flashes, plus a Canolite for my Canonet 28). I'm still puzzling through the mysteries of HSS, TTL-II or whatever they are. Most of these issues did not arise with my Nikon F or Nikkormats.</p>

[peter_k6]

<p>Thank you all for advices</p>

[sarah_fox]

<p>You're quite welcome, Peter. :-)</p>

<p>JDM, I know what you mean re the fancy modern flashes. I keep learning/forgetting/relearning the darned things. I simply don't use them enough to retain a decent working knowledge. Usually when I need flash, I use my Vivitar 285hv units off shoe and in manual mode. No need/desire for automation. All I want and need is light. ;-)</p>