And the Sigma auto focus issues continue !

i really don't understand all the problem with Sigma lenses. Do they really have that much focusing issues? I tried few copies of the 30 1.4 and they all performed great. Did Sigma really screw up that bad? If they did i would expect they'd do a recall and take back all the faulty lenses.

I am glad you brought this up cause i noticed each one of the threads that hit the forum when he posted them thinking i would actually gain any knowledge from a thread.

philwillmedia wrote in post #11657187
GC, the OP refuses to accept that the only constant in his "testing" is himself.
Can you honestly say to yourself that there is not even the slightest possibility that equipment is not the problem but the operator is...
11 consecutive lenses that are "faulty" - I seriously doubt it.
Several different bodies that are "faulty" at the same time lenses are - I doubt that too.

Maybe you should have a look at these threads by the OP.
Firstly this...https://photography-on-the.net/forum/showthre​ad.php?t=984731
and this one
https://photography-on-the.net/forum/showthre​ad.php?t=980470
both preceeded by this one...
https://photography-on-the.net/forum/showthre​ad.php?t=980364

Hmm...multiple bodies AND lenses with focusing issues even after micro adjusting, all used by the same person.

GC, can you not see a pattern here?

mdgrwl wrote in post #11654819
no, one shot drive method, no AI Servo

the lens wouldn't hunt whatsoever

i would fire 5 shots off in a row without moving the focus point at all

then i tried a different method where i shot 5 shots off, but in between i would focus on something else, then re-focus on my subject to give it a "fresh" focus. same thing. 2-3 of 5 OOF

guys really... why does this thread supprise you so much? Sigma has been reported on by hundreds to have horrible compatibility issues with Canon bodies.

And you still bought a Sigma? As they say on ESPN, "C'mon man!"

cristphoto wrote in post #11659011
And you still bought a Sigma? As they say on ESPN, "C'mon man!"

I've never had a problem with Sigma lens that I bought new . All worked great right out of the box . So I really don't know what the problem is .

CountryBoy wrote in post #11659054
I've never had a problem with Sigma lens that I bought new . All worked great right out of the box . So I really don't know what the problem is .

This is my experience as well.

CountryBoy wrote in post #11659054
I've never had a problem with Sigma lens that I bought new . All worked great right out of the box . So I really don't know what the problem is .

I agree. I have no rub againt third party equipment (one would guess they have to be competitive to survive). I've been a photographer for over 30 years and a paid pro for over 10 years and work the heck out of my equipment. I've hit doorways hard with lenses, dropped equipment, shot boat races and had everything totally doused and it keeps on working. That's why I stick with Canon. Their support when I call is helpful and professional. Maybe I'm lucky but I've only had to have one body adjusted under warranty and sent one lens back (wasn't defective per se, but I didn't like the feel of the focus ring). I also purchase fine equipment knowing I plan on giving it a long hard life. I'm not going to pile on here but this poster is either the unluckiest person in the world or he would help himself by speaking with an experienced photographer for advice. I'm a bit curious about the store where all these purchases are made. Assuming the poster is correct about all the faulty products (?), this place is a mess. I only purchase from Adorama or B&H for the big ticket items and as stated previously, problems are virtually non-existent. I wish the poster well and hope he gets all these issues fixed.

When I get home tonight, I'm going to try to find the shots to show you guys as proof its just a bunk lens. But I believe I may have deleted them in disgust. I hope I still have them to show you guys.

I admit I got a little defensive, but really the underlying tone in most comments toward me was I'm basically an idiot, its user error and I don't know what I'm doing. How could I not get a bit defensive.

I doubt most of you guys even read the post where I described my "real world" style shooting. Its not 100% real world, but its not shooting batteries.

Just to be clear this is exactly what I did, and after so, deemed it to be a bunk lens.

How can you explain how this is user error? Here is EXACTLY what I did:

- Set up a 2 liter bottle of Soda outside on my stoop
- Found a contrasty point to focus on
- Fired off 5 shots in a row on the same exact point at same camera settings (no focus/recompose, I stress, no focus/recompose, the camera didn't move, and I focused on the same exact point on the bottle)
- Change aperature, fired off 5 shots again
- Moved back a few steps, fired off 5 shots again
- changed aperature, fired off 5 shots again.

*Note - shutter speeds were very fast so camer shake were not a factor 1/1600 shutter speeds. Also tripod mounted.

Results: Of each set of 5 shots 2-3 were OOF.

Explain that to me. Explain how this isn't simple focus shift and that its user error.

I personally really hate such tests, but I understand that you want to get this argument out of the way.

What aperture did you use? How far away were you from the subject? Did you use a tripod and timer/remote?

I'm looking forward to the samples.

Rsyx wrote in post #11664721
I personally really hate such tests, but I understand that you want to get this argument out of the way.

What aperture did you use? How far away were you from the subject? Did you use a tripod and timer/remote?

I'm looking forward to the samples.

yes, I want to clear my name of being a noob and an idiot basically. this was no user error.

tripod mounted, no remote. shutter speeds were very fast (very bright out side) 1/1600 some 1/2000 so I wasn't worried about camera shake.

I did all aperatures I intended to use the lense in

Up close (4-5 feet) - 1.4 / 1.6 / 1.8
move back a little (6-9 feet) 1.8 / 2.0 / 2.2

Same results 2-3 were OOF.

I cannot make this clear enough. I did NO focus/recompose for this. I used the center AF point, and also the outer AF points.

I also used my 7D's SPOT AF feature, and regular AF. I did over 200 shots that morning. Same results.

I basically explored ALL possibilities.

mdgrwl wrote in post #11664707
When I get home tonight, I'm going to try to find the shots to show you guys as proof its just a bunk lens. But I believe I may have deleted them in disgust. I hope I still have them to show you guys.

I admit I got a little defensive, but really the underlying tone in most comments toward me was I'm basically an idiot, its user error and I don't know what I'm doing. How could I not get a bit defensive.

I doubt most of you guys even read the post where I described my "real world" style shooting. Its not 100% real world, but its not shooting batteries.

Just to be clear this is exactly what I did, and after so, deemed it to be a bunk lens.

How can you explain how this is user error? Here is EXACTLY what I did:

- Set up a 2 liter bottle of Soda outside on my stoop
- Found a contrasty point to focus on
- Fired off 5 shots in a row on the same exact point at same camera settings (no focus/recompose, I stress, no focus/recompose, the camera didn't move, and I focused on the same exact point on the bottle)
- Change aperature, fired off 5 shots again
- Moved back a few steps, fired off 5 shots again
- changed aperature, fired off 5 shots again.

*Note - shutter speeds were very fast so camer shake were not a factor 1/1600 shutter speeds.

Results: Of each set of 5 shots 2-3 were OOF.

Explain that to me. Explain how this isn't simple focus shift and that its user error.

When you are in the exact same place w/the exact same settings with 5 shots fired in rapid succession and 5 different results, that is not likely the lens and that is not focus shift. It could be the body.... that's a pretty weird outcome...

The focus shifts I've experienced were all consistent. Stopping down resulted in consistent front/back focus. Different distances drove consistent front/back focus. Again, what you describe is a little out of the ordinary of typical "bad lens" behavior.

Regardless, you should probably request a mod to close this thread.

hieu1004 wrote in post #11664750
When you are in the exact same place w/the exact same settings with 5 shots fired in rapid succession and 5 different results, that is not likely the lens and that is not focus shift. It could be the body.... that's a pretty weird outcome...

Regardless, you should probably request a mod to close this thread.

perhaps it is my 7D, but i doubt it but my gut feeling is its more the pairing of the Sigma with 7D.

I didn't do the same exact "test" with a Canon lens, but I did shoot around my house to check AF accuracy and just about every single shot was in focus.

Either it was the Lens, or the pairing on the Sigma Lens & 7D.

I'm getting my new 35L today (UPS "out for delivery")
I'm going to fire off like 100 shots around my house and check for AF accuracy.

My gut feeling is Sigma just hasn't mastered reverse engineering these Canon bodies.

I gotta be honest, I had similar problems with both the 30mm and 50mm from Sigma. Sometimes subject distance would affect focus accuracy, other times it was the amount of permissible light. There were more throw aways than keepers. I consider myself a pretty reasonable person, but these were just unacceptable. There were all sorts of shooting factors that would cause it to be wildly out of focus, and I need something I can trust when I'm shooting. Ultimately I had to say goodbye to Sigma.

It's funny, I'm not sure what to think anymore. So many people swear by Sigma as the best mid-grade choice for lenses, and yet my experience was completely the opposite. I admittedly can say I liked most of the aspect of Sigma lenses, for the price they were a deal. But the AF was so unpredictable, I couldn't justify keeping them. Compared to Canon's similarly priced non-L lenses, the Sigmas certainly are an intriguing offer... but unless they can get the AF right, it'll never really be an option for me. I'd rather spend the extra bucks and step up to an L... which are superior in AF, Color Rendition, Build Quality, and usually even Bokeh. To me that's worth the extra $500-$800.

^People's experiences will definitely vary. My local store doesn't even carry Sigma because of the said quality issues. I've been one of the more lucky ones (I guess?) and haven't had any issues with my Sigma. The AF isn't as speedy as Canon's USM in the L series, but I learned to work around them. I've owned and own lenses that are considered best in class and I rank the Sigma very high up there. That's too bad that the quality varies so much - because if you get a good copy, it is VERY good.

mdgrwl wrote in post #11664782
perhaps it is my 7D, but i doubt it but my gut feeling is its more the pairing of the Sigma with 7D.

I didn't do the same exact "test" with a Canon lens, but I did shoot around my house to check AF accuracy and just about every single shot was in focus.

Either it was the Lens, or the pairing on the Sigma Lens & 7D.

I'm getting my new 35L today (UPS "out for delivery")
I'm going to fire off like 100 shots around my house and check for AF accuracy.

My gut feeling is Sigma just hasn't mastered reverse engineering these Canon bodies.

I think you'll be much happier with the 35L. No offense to Sigma, AF excluded they're a great value for the money. But there's not a Sigma out there that touches L primes... not even the 50L. My point is you're not just gaining AF accuracy... the overall rendition from Colors to Bokeh is just better on an L Prime.

mdgrwl wrote in post #11664782
perhaps it is my 7D, but i doubt it but my gut feeling is its more the pairing of the Sigma with 7D.

I didn't do the same exact "test" with a Canon lens, but I did shoot around my house to check AF accuracy and just about every single shot was in focus.

Either it was the Lens, or the pairing on the Sigma Lens & 7D.

I'm getting my new 35L today (UPS "out for delivery")
I'm going to fire off like 100 shots around my house and check for AF accuracy.

My gut feeling is Sigma just hasn't mastered reverse engineering these Canon bodies.

So seems you just got into photography and you already have determined that Sigma..the biggest lens manufacture out there still hasnt got the reverse engineering down. Why cant it be your 7D..I think this 7D might have some issue in helping it be off..Like I said my 24-70L was 0 MA on my 1D3 and it was dead nuts on every shot..now with my 7D its -10MA and i get some stuff your getting..I will take 5shots in a row and 2-3 will be little out of focus.

realmike15 wrote in post #11664854
I think you'll be much happier with the 35L. No offense to Sigma, AF excluded they're a great value for the money. But there's not a Sigma out there that touches L primes... not even the 50L. My point is you're not just gaining AF accuracy... the overall rendition from Colors to Bokeh is just better on an L Prime.

I guess speaking from all that experiance you have with all those L primes in your sig