And the Sigma auto focus issues continue !

So I had what I thougth was a perfect Sigma lens. Slight back focus issue but I fixed that with my MA.

Went out today shooting my "Strangers Project", first time using the Sigma 50mm 1.4 and I had about a 40% keeper rate!

I'm not going to post all the photo's - way too many... but the Sigma would hit or mis for no reason at all!!!

I would move at all, and the subject would move. Shots at 2.0 would just be way OOF, and then the next shot, same settings same everything would be sharp.

Shutter speeds were crazy fast too at like 1/2000 sec.

Very dissapointing. I can't have a lens that gives me 40% keeper rates... sux, because the IQ is so nice...

what type of AF were you using?

looked at your previous threads...you've had issues with 2 canon 50mm AF'ing...and now a sigma 50mm AF issue...dude there's a good chance it might not be the lens..if it is you've got the worst luck in the world

DreDaze wrote in post #11649162
what type of AF were you using?

looked at your previous threads...you've had issues with 2 canon 50mm AF'ing...and now a sigma 50mm AF issue...dude there's a good chance it might not be the lens..if it is you've got the worst luck in the world

today I was using spot focusing on my 7D to be as precise as possible. always on the eyes of the people.

the two Canons one was just soft period, and the other had back focus issues. if I had my 7D i could of fixed the back focus issue....

There was one thing consistant with the Sigma today. If I was close to the subject (4 feet) it would focus dead on at 1.4 - crystal clear.

If I was like 7-8 feet back, even at f2.0 - OOF shots all over the placed.

Focus SHIFT.

mdgrwl wrote in post #11649218
There was one thing consistant with the Sigma today. If I was close to the subject (4 feet) it would focus dead on at 1.4 - crystal clear.

If I was like 7-8 feet back, even at f2.0 - OOF shots all over the placed.

Focus SHIFT.

same problem I had with my Sigma 50..but it was the one I bought the week it came out..up to 8feet it was razor sharp..when i got further out like 15-20 feet the focus was off by feet not inches. did you buy it used?

This was on my old 1DMKII..I even sent the lens to Sigma and they said they had no issues on their stuff and it was in spec. I sold it..bought another one last year..it was much much better but ended up selling it due to lack of use. Thats bad thing with that lens..its a gamble.

mdgrwl wrote in post #11649218
There was one thing consistant with the Sigma today. If I was close to the subject (4 feet) it would focus dead on at 1.4 - crystal clear.

If I was like 7-8 feet back, even at f2.0 - OOF shots all over the placed.

Focus SHIFT.

Someone reported a similiar problem in the Sigma 85 f1.4 thread.

i meant what mode...AI Servo, AI Focus, or One shot?

If it was me, the only thing possible it could be was my method. I used the focus & re-compose method.

DreDaze wrote in post #11649249
i meant what mode...AI Servo, AI Focus, or One shot?

One Shot - non moving subjects.

mdgrwl wrote in post #11649261
If it was me, the only thing possible it could be was my method. I used the focus & re-compose method.

Why on a 7D with all the focus points?

send it back.

05Xrunner wrote in post #11649233
same problem I had with my Sigma 50..but it was the one I bought the week it came out..up to 8feet it was razor sharp..when i got further out like 15-20 feet the focus was off by feet not inches. did you buy it used?

This was on my old 1DMKII..I even sent the lens to Sigma and they said they had no issues on their stuff and it was in spec. I sold it..bought another one last year..it was much much better but ended up selling it due to lack of use. Thats bad thing with that lens..its a gamble.

i'm still within the 30 day return policy. i'm just going to get the Canon... i'm reading way too much about Sigma's issues reverse engineering to Canon mounts. I can't have a 40% keeper rate. Though I don't like the Canon's 50 1.4 as much, i'll love the fact my shots are in focus! lol.... sigh.

mdgrwl wrote in post #11649209
today I was using spot focusing on my 7D to be as precise as possible. always on the eyes of the people.

the two Canons one was just soft period, and the other had back focus issues. if I had my 7D i could of fixed the back focus issue....

Or are you referring to spot metering?

Not a good idea for absolute sharp images, especially at wider apertures..

mdgrwl wrote in post #11649261
If it was me, the only thing possible it could be was my method. I used the focus & re-compose method.

that could very easily be it...it looks like most your flickr shots were done at f1.6...
http://visual-vacations.com …focus-recompose_sucks.htm

yogestee wrote in post #11649278
Or are you referring to spot metering?

no the 7D has Spot focus and normal focus..spot focus uses a much smaller focus point to get a more accurate focus but its a little bit slower