Sigma 150-500

Girish, check your camera. My 40D was back focusing enough to cause alot of OOF photos for the last 6 months. It doesn't show up much on shorter lenses, but the long lenses are more pronounced. How many photos did this happenin? Center point/one shot too? My 40D jumps all over the place, just took it in today. Hope yours is an easy fix. It's not always the lens though. I've been bringing in lenses for calibration like crazy this year, and since the sigma badly focused with the 40D, I switched to my 20D and problems went away. It autofocused better on the 1.4x teleconverter too. The 40D would not at all. Like I said, I sure hope the issue can be resolved for the 3rd time this year. No use buying a $5000 lens if the camera is faulty. I may rent a different one just out of curiosity.

Linda,

Thanks a lot for your suggestions !

Couple of folks have told me that the focus was not the subject's eye (mostly birds) after seeing my post-processed pics taken with Sigma 150-500mm. I didn't get it then - because when I checked my RAW file, the focus was spot-on !! So, I left it at that. However, it seems to make a bit of sense to me now - the front-focussing issue.

Unfortunately, I've no clue who the culprit is - the camera or the lens . I'm not an expert and all kind of useful tips/techniques will help.

Please elaborate when you say "Check your camera" - do you mean I should take it to Canon service centers ?? How did you resolve the issue with 40D ?

Since rentals for camera is not very prevalent here, the best I can do is to borrow my friend's 400D to isolate the problem.

Thanks once again.

Netgarden wrote in post #5913273
Girish, check your camera. My 40D was back focusing enough to cause alot of OOF photos for the last 6 months. It doesn't show up much on shorter .

I've finally got mine and posted some comparisons with Canon 100-400
http://www.pbase.com …ma_150500_vs_ca​non_100400

Sofar it seems to compare quite well with my 100-400. I will keep updating it...

In case anyone in UK is interested: £599.99 including next day delivery from RGB technology.
http://www.rgb-tech.co.uk/browse/56 (Sigma lens page)

evandavies wrote in post #5960812
I've finally got mine and posted some comparisons with Canon 100-400
http://www.pbase.com …ma_150500_vs_ca​non_100400

Sofar it seems to compare quite well with my 100-400. I will keep updating it...

In case anyone in UK is interested: £599.99 including next day delivery from RGB technology.
http://www.rgb-tech.co.uk/browse/56 (Sigma lens page)

I appreciate your thoughts, but I will have to disagree about the OS statement. The Sigma is FAR greater than the Canon in this regard. I have been able to get sharp shots at 1/25 at 500mm! The Canon couldn't do 1/25 at 400mm IMO.

Hmmm... maybe mine is defective????
I'll keep testing.

(Maybe I was shaking with excitement )

EDIT: Just tested again @400mm, swapping between the two and the Sigma has slightly more high frequency movement than the Canon
Can another owner chime in...?

evandavies wrote in post #5960900
Hmmm... maybe mine is defective????
I'll keep testing.

(Maybe I was shaking with excitement )

Definitely check it out. I also got this one at 1/60!

HTTP response: NOT FOUND | MIME changed to 'image/gif'

wow, that's awesome!

Nice, Mikey!! The OS is definitely more effective than the older generation 1-4 IS unit. Without any doubt about it.

goatee wrote in post #5961104
wow, that's awesome!

LightRules wrote in post #5961114
Nice, Mikey!! The OS is definitely more effective than the older generation 1-4 IS unit. Without any doubt about it.

Thanks guys. Yup, without the OS I wouldn't be able to shoot anything unless in bright sunlight. The shutter speed would just be too slow and I have decently steady hands.

LightRules wrote in post #5961114
The OS is definitely more effective than the older generation 1-4 IS unit. Without any doubt about it.

Damn, then mine is defective

evandavies wrote in post #5961200
Damn, then mine is defective

Evan, you should be able to get reasonably sharp images at 1/50th. That's about 4 stops gain with 800mm FOV. I was able to get about 4-5 stops consistently.

LightRules wrote in post #5961262
Evan, you should be able to get reasonably sharp images at 1/50th. That's about 4 stops gain with 800mm FOV. I was able to get about 4-5 stops consistently.

Same here.

Oh, goodies, I woke to wood...Bigmos is Out For Delivery!!! YeeeeeHaaaawwww!!!

In2Photos wrote in post #5961051
Definitely check it out. I also got this one at 1/60!

HTTP response: NOT FOUND | MIME changed to 'image/gif'

NEAT picture, it's almost like there is a "sphere of focus" (rather than the phrase 'depth of field') around the fuzzy bunny critter. I love the effect.

Yes, I can get pretty good shots even at 1/40 sec but I'm talking about comparing directly with the 100-400.

The OS doesn't seem much better than the 100-400 IS even with both @400mm

When the OS is active you still see a bit of camera shake right? (Duno how to express it... not drift but a bit of shaking)