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Topic: Canon 7D +100-400 AF Problem
Username: tom3
Posted 2012-06-19 17:42:52 and read 9470 times.

Hello

I've bought a 7D and now I have a few issues with some of my images , where some parts of the aircraft are out of focus/soft!

With my old 30D + 100-400 I had never such a problem.

Here is an example (unedited and downscaled to 1600x1067)

http://img5.fotos-hochladen.net/uploads/mycefc9gma7u1j8.jpg

The winglets and a part of the nose looks out of focus/soft , but the tail section looks right to me.

Hope to get some advice.

Thanks Tom

Topic: RE: Canon 7D +100-400 AF Problem
Username: Silver1SWA
Posted 2012-06-19 17:52:23 and read 9463 times.

First of all, it would help to see at full resolution.

Second, the shot looks soft throughout. And do you have examples under better conditions?

Topic: RE: Canon 7D +100-400 AF Problem
Username: tom3
Posted 2012-06-19 18:17:55 and read 9435 times.

Here is the original file

http://img585.imageshack.us/img585/8125/mycef1.jpg

Uploaded with ImageShack.us


And here is an image in better conditions

http://img341.imageshack.us/img341/520/lxpcv.jpg

Uploaded with ImageShack.us

Tom

[Edited 2012-06-19 18:29:41]

Topic: RE: Canon 7D +100-400 AF Problem
Username: NZ107
Posted 2012-06-19 19:19:48 and read 9399 times.

Quoting tom3 (Reply 2):

Wow, that Cargolux shot really looks out. Is there some other factor, such as a filter, which could cause some distortions?

Is something dirty? Can you use other lenses on that body without any issues?

Topic: RE: Canon 7D +100-400 AF Problem
Username: tom3
Posted 2012-06-19 19:29:48 and read 9387 times.

I have not used filters and there is no dirt , I have only tried with the 100-400. But also for me it looks quite strange since I had never such problems till now!

Tom

Topic: RE: Canon 7D +100-400 AF Problem
Username: clickhappy
Posted 2012-06-19 21:14:30 and read 9366 times.

The Cargolux shot is pretty blurry, but most likely due to it being 400mil at 1/400. But is that really ISO100? That grain is quite noticeable. That shot was also at f/7.1, have you tried stopping it down to f/8 or f/11?


The (I think?) Hawker is also long (370mm) and relatively slow (1/500). Again at f/7.1

What are your AF settings?

Topic: RE: Canon 7D +100-400 AF Problem
Username: kukkudrill
Posted 2012-06-20 00:20:50 and read 9340 times.

I'd hazard a guess and say that, aside from the grain, it looks like a lens problem. In both shots the trouble appears on the right hand side.

Topic: RE: Canon 7D +100-400 AF Problem
Username: NZ107
Posted 2012-06-20 00:33:51 and read 9334 times.

Quoting clickhappy (Reply 5):
The Cargolux shot is pretty blurry, but most likely due to it being 400mil at 1/400.

It shouldn't be that bad though.. Surely. Seems like a routine shooting session to me, something you expect to nail day in day out with similar settings.

Topic: RE: Canon 7D +100-400 AF Problem
Username: Silver1SWA
Posted 2012-06-20 03:50:59 and read 9303 times.

Something definitely isn't right with the Cargolux shot. It almost looks like a severe vibration effect. Did you have IS on or off? If on, try turning it off and see what happens.

Topic: RE: Canon 7D +100-400 AF Problem
Username: jpmagero
Posted 2012-06-20 04:11:00 and read 9299 times.

I shoot with the same combination (7D + 100-400) and haven't had the focus issues you mention, but I do see that all my shots are very grainy, even at ISO100. Except in extremely bright light on a very bright surface, I *always* have grain in my images. It's not so much of an issue for printing through 13x19, but is noticeable on screen and for sites like this can cause issues (not that this is my only problem getting HQ photos on here). I've always attributed this to the 7D sensor, not the lens. Other IQ issues are my technique, I'm sure.

This sample 100% crop is not a HQ shot, but I don't have many samples on my work PC. Either way, you can see the extreme (IMO) grain present in the shadow and sky.


Shot at ISO100, 1/3200, f2.8 at 200mm

Topic: RE: Canon 7D +100-400 AF Problem
Username: Silver1SWA
Posted 2012-06-20 05:19:19 and read 9275 times.

Quoting jpmagero (Reply 9):

The noise/grain at ISO 100-200 is a characteristic of the 7D. It's usually not a big issue and is easily managed with slight noise reduction in ACR or LR, but I will say I'm getting tired of the 7D image quality. Fantastic camera, but it suffers in the IQ department.

Back to the OP, I'm wondering if you have hada flawed lens this whole time but couldn't see the problem at the relatively small resolution of your 30D. At 18mp, the 7D shows any weakness in a lens.

Topic: RE: Canon 7D +100-400 AF Problem
Username: JakTrax
Posted 2012-06-20 06:43:57 and read 9254 times.

Quoting Silver1SWA (Reply 10):
Back to the OP, I'm wondering if you have hada flawed lens this whole time but couldn't see the problem at the relatively small resolution of your 30D. At 18mp, the 7D shows any weakness in a lens.

Exactly what I was about to say. I had a 28-105mm lens on my old 30D and it was fantastic, but once I put it on the 50D the softness at the frame edges was noticeable. My first 100-400 was terrible one side (I forget which - seem to recall the left), so I swapped it for another and that one was (and still is) fine. Had I coupled it with my 30D the issue may have been less obvious.

I have to be honest and say that, in addition, it appears that you are using the 100-400 in conditions that any lens would falter in. This time of year I keep mine in its box as atmospheric conditions are just too unreliable to guarantee great pictures. Both your example images seem to be at very long focal lengths, with mediocre/poor light, and insufficient shutters. The thing with this theory, of course, is that such limitations would have presented themselves way before now, with the old 30D.

I personally reckon it's a case of the first theory - the resolving power of the 7D revealing softness in the lens.

Karl

Topic: RE: Canon 7D +100-400 AF Problem
Username: clickhappy
Posted 2012-06-20 10:33:33 and read 9204 times.

John, not sure why you have shot that Falcon at f/2.8 and 1/3200!

Topic: RE: Canon 7D +100-400 AF Problem
Username: jpmagero
Posted 2012-06-20 11:17:40 and read 9195 times.

Quoting clickhappy (Reply 12):
John, not sure why you have shot that Falcon at f/2.8 and 1/3200!

I know...this was just a test shot to see how the shutter speed would affect heat haze and happened to be one of the only shots on my work laptop at ISO100 for the purposes of showing the noise I see.

[Edited 2012-06-20 11:19:42]

Topic: RE: Canon 7D +100-400 AF Problem
Username: tom3
Posted 2012-06-20 11:42:13 and read 9188 times.

Hello

I've took this photo today , what do you think about the edited result ?

For me it looks a bit better than the other shots I took recently!

http://img804.imageshack.us/img804/1327/b18720.jpg

Uploaded with ImageShack.us


Tom

Topic: RE: Canon 7D +100-400 AF Problem
Username: KelvinCJ
Posted 2012-06-21 06:42:46 and read 9100 times.

Just a thought here - but you mention you bought it recently. Any chance this could be a firmware issue?

I have read lots of online reports about similar issues and most were resolved by updating the firmware.

I know it is probably unlikely but just an idea. Having said that though I can only imagine said issue if you have an older stock version of the 7D as the update has been around for over a year now?

I think the edited image is better - as it should be! Unfortunately I cannot say anything specific as I am viewing on a smartphone but the general quality appears better than the others to my eyes.

Granted such an issue should affect the whole image but if you have older firmware it is worth a try.

[Edited 2012-06-21 06:45:35]

Topic: RE: Canon 7D +100-400 AF Problem
Username: tom3
Posted 2012-06-21 07:34:26 and read 9076 times.

Hello Kelvin

When I bought the 7D , it had already the latest firmware version 1.2.5 , so I don't think it is a firmware issue.

Tom


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