One of the biggest complaints when the Canon 60D came out was the lack of AFMA. When you spend big money on cameras and lenses you want to get the best out of them.
Now Sigma releases a smart and inexpensive device that allows such modifications even more accurately, on several paramenters and without the need of an AFMA function in camera.
Albi86 wrote:
One of the biggest complaints when the Canon 60D came out was the lack of AFMA. When you spend big money on cameras and lenses you want to get the best out of them.
Now Sigma releases a smart and inexpensive device that allows such modifications even more accurately, on several paramenters and without the need of an AFMA function in camera.
What is there to complain about?
It's called Sigma, that's their problem, not a cool name... They should change their name to "Sigwalt über"
I have had 2 17-70/2.8-4 and currently 2 of the new version. none have had any real issues with any of them. I also have the current 150 macro and had the previous version. other then minor AF tweaks these lenses have performed as adverted.
wiseguy010 wrote:
Lenses just have to focus properly straight out of the box without the need for additional fine tuning by the customer.
If you accept this without any questions, then we have a different opinion about quality. But that was already clear to me.
The problem with this thought, in my opinion, is if I take any wide aperture lens out of the box (Nikon, Sigma) and put it on 5 copies of the same Nikon camera (and the same applies to Canon) it will require slightly different AF on about 2 of the 5 cameras. I do this daily.
So, that makes the problem a camera problem not a lens problem, correct? And therefore the QA issue is with the camera maker?
Except the opposite holds too. If I put 5 copies of a lens on one camera (including Nikon) 2 of them will require MA.
Given the complexity of AF and the quality of sensors we have these days I think reality is we can detect the limits of manufacturing tolerance. I'm a QA freak and spend my days optically adjusting lenses - but reality is there are QA limits. Nothing can be manufactured in multiple copies identically if you measure carefully enough.
I wouldn't have minded using the fine tuning adjustment within Nikons +20/-20 but when focus points left/centre/right vary significantly there is an obvious issue.
Cosmetically I found the nikon 35mm 1.4 to be nicer, the sigma seems weirdly long & almost awkward.
Roger has identified the problem: what were, once, acceptable production tolerances with F2.8 lenses and 6-10 Mp is now out of spec with 24-36 Mp and F1.4-2.0 lenses. With stagnant and now plunging DSLR camera sales the pressure is on Camera companies to cut costs. We have read on this forum of complaints about Nikon's QC and service while they have restricted parts sales to independents.
I started with the 5D classic (no AF MA) and the F 1.4 35mm L. I shot for 18 months with MA since AF insured that none of my captures had critical focus. F1.4 MA focus was difficult but at least there it was possiblility of critical focus. Only when I bought the MK III, with MA, did I realize my 35L was severely front focusing.
I switched from Canon's Mk III and their super speed lenses to Nikon's D3. With the D3's extra hi ISO I was able to use their F2.8 zoom lenses to "frame up" my fast moving dancers. The bonus was much
more reliable AF and more DOF.
My experience with MA is that best results are only obtained at the venue's lighting, shooting distance and zoomed FL So I trade lab conditions for a field MA check using the, magnified, JPEG thumbnail on the VF. Some dealer or rental company could make a business of selling calibrated QCed bodies and lenses. I would certainly pay money to have my core kit tweeked.
RCicala wrote:
The problem with this thought, in my opinion, is if I take any wide aperture lens out of the box (Nikon, Sigma) and put it on 5 copies of the same Nikon camera (and the same applies to Canon) it will require slightly different AF on about 2 of the 5 cameras. I do this daily.
So, that makes the problem a camera problem not a lens problem, correct? And therefore the QA issue is with the camera maker?
Except the opposite holds too. If I put 5 copies of a lens on one camera (including Nikon) 2 of them will require MA.
Given the complexity of AF and the quality of sensors we have these days I think reality is we can detect the limits of manufacturing tolerance. I'm a QA freak and spend my days optically adjusting lenses - but reality is there are QA limits. Nothing can be manufactured in multiple copies identically if you measure carefully enough. ...Show more →
Good point. The manufacturing tolerances for both camera and lens optical paths are probably still what they were in the film days, that's the issue. They were perhaps ok with 4MP or 6MP. But as we get higher and higher MP cameras, these issues get more and more obvious unless those tolerances are tightened at the same pace the MP go up.
2 questions. Would you have to reset the lens calibration in the Nikon or Canon camera back to 0 if it is already calibrated and what do you do with more than one camera that has different calibration numbers from eachother?
mstein274 wrote:
2 questions. Would you have to reset the lens calibration in the Nikon or Canon camera back to 0 if it is already calibrated and what do you do with more than one camera that has different calibration numbers from eachother?
That's a good question.
If they're additive you can actually get to +/- 40.
roger1 wrote:
Ken Rockwell has said it right about the Sigma USB. Read his 'tinkerer vs pro' post.
I Like Ken but I have been a pro shooter for probably longer than he has been alive and Nikon have focus adjust for a reason. My D3s rarely needs focus adjust and the d800 got sent in twice and both times were with nikon lens attached. If the dock can make the Sigma 35 I own focus more accurately, I consider that a major plus to the style of photography I now use. I am not happy to have to take the time to adjust the focus myself, but that a ton less hassle than shipping lens and cameras back to NPS.
roger1 wrote:
Ken Rockwell has said it right about the Sigma USB. Read his 'tinkerer vs pro' post.
Mmmmmm, so spending a couple of minutes AF tuning a lens to perfect focus once and for all is a waste of time and completely unprofessional? BTW Ken also doesn't have time to shoot RAW or use a tripod because he thinks it's a waste of time... Good luck listening to him
