Go Back   Steve's Digicams Forums > Post Your Photos > Wildlife Photos

Reply
 
Thread Tools Search this Thread
Old Jan 11, 2008, 7:50 PM   #1
Senior Member
 
squirl033's Avatar
 
Join Date: Dec 2004
Posts: 6,696
Default

so, i got a little break in the clouds and rain this afternoon, and took my camera for a walk at the park. i'm still trying to get this 100-400L lens to work as well as my Sigma in terms of image quality, and so far, it's failing miserably. anyway, in spite of its poor focusing (plenty fast, but not very accurate!), i did manage a couple of sort of acceptable shots of a downy woodpecker searching for lunch in the bark of a poplar...






squirl033 is offline   Reply With Quote
Sponsored Links
Old Jan 11, 2008, 7:57 PM   #2
Senior Member
 
Join Date: Dec 2003
Posts: 3,748
Default

Hi Squirl, I'm always pleased with the results of my 100-400 and I also have the Bigma which is rarely used because of the credible work of the 100-400. I would suggest that you send it in for calibration if possible, I've had 2 copies and both have been excellent performers. Beyond the technical stuff, I like these shots, especially the first one, because of it's point of view, from the bottom up, the bird is definitely interested in what you are doing with your lens :-).

Super job, hope things work out eventually with that lens. It's one of my very favorites personally.
Normcar is offline   Reply With Quote
Old Jan 11, 2008, 8:54 PM   #3
Senior Member
 
squirl033's Avatar
 
Join Date: Dec 2004
Posts: 6,696
Default

thanks, Norm. looking at these, it appears to be back-focusing a bit... a suspicion that i kinda confirmed with some shots taken after these. i saw a GBH standing on a sandbar some distance away, and took some shots. i had shutter speeds of between 1/400 and 1/640, at f/7.1, with IS on and my 40D on a monopod. should have been nice and sharp. the heron was hopelessly blurred, but the water behind it was quite a bit clearer. i'm afraid this little doggie will have to go back to Canon for repairs. good thing i have the EX 80-400 as a back up!
squirl033 is offline   Reply With Quote
Old Jan 11, 2008, 8:56 PM   #4
Senior Member
 
rondv's Avatar
 
Join Date: Oct 2006
Posts: 166
Default



Squirl.. It looks to me like your lens may be back focusing. In the first photo the tree above the WP is in focus and in the second the tree and the branch above seems to be in focus. Here is a link with a test chart you can print to determine if you have front or back focus issues. Hope you find the problem.

http://focustestchart.com/focus21.pdf

Ron


It looks like you posted while I was typing.
rondv is offline   Reply With Quote
Old Jan 11, 2008, 9:47 PM   #5
Senior Member
 
squirl033's Avatar
 
Join Date: Dec 2004
Posts: 6,696
Default

thanks, Ron... the article looks like it's aimed at Nikon cameras where the camera back-focuses because of sensor alignment, but the symptom certainly looks the same! i know my 40D works fine with my Sigma lens, and with my two shorter lenses (both Tamrons), so i'm fairly certain the camera body isn't at fault. hopefully, if i send the lens to the nice folks at Canon, they can recalibrate it or whatever it is they do, and make it work right...
squirl033 is offline   Reply With Quote
Old Jan 13, 2008, 11:55 AM   #6
Senior Member
 
thekman620's Avatar
 
Join Date: Feb 2004
Posts: 6,084
Default

Very nice shots Squirl. These little guys are tough to shoot in our area. They don't seem to sit too long, and always seem to have branches in front of them when I try shooting them. After seeing these shots, and your previous ones, I also think you might need a calibration. If you bought it locally, maybe you could exchange it before sending it in? It does appear to be backfocusing a bit...cheers..Don
thekman620 is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 7:46 PM.