1Ds MkIII - AF Microadjustments

FM Forum Rules
Canon SLRs, primes, and zooms lenses reviews

FM Forums \| Canon-mount SLRs \| Join Upload & Sell	Search Used
1 2 end

Archive 2008 · 1Ds MkIII - AF Microadjustments

SoundHound
Offline
Dedicated FM
Upload & Sell: On

p.2 #1 · 1Ds MkIII - AF Microadjustments

I tweaked my 35L for 8' and now it's way out at 20." So I am not certain that, at big aperture of F1.2-F1.8 that many lenses will not AF properly over the entire distance range.

Sep 03, 2008 at 04:49 PM

jjlphoto
Offline
Dedicated FM
Upload & Sell: Off

p.2 #2 · 1Ds MkIII - AF Microadjustments

Don't forget that some lenses actually exhibit what is known as "focus shift" as the aperture is stopped down. Modern lens designers try to avoid or minimize it, but it does exist.

Edited on Sep 03, 2008 at 04:53 PM

Sep 03, 2008 at 04:53 PM

Daan B
Offline
Dedicated FM
Upload & Sell: Off

p.2 #3 · 1Ds MkIII - AF Microadjustments

I needed a +15 micro adjustment for my 35L. ALthough I use the lens mostly at about 2-3 meters, it doesn't seem to have any problems focusing at infinity. The same for my 85L II and 135L (both needed +5).

Some lenses perform better at closer distances while other perform better at long distances and some perform good at both closer and longer distances. Maybe the MA exaggerates these design related characteristics in some way?

Edited on Sep 06, 2008 at 11:33 AM

Sep 06, 2008 at 11:31 AM

xrayvision
Offline
Upload & Sell: Off

p.2 #4 · 1Ds MkIII - AF Microadjustments

Here's an interesting finding. The 200 1.8 is dead on at 10 ft. -no adjustment. At 60 ft. it requires -13. Between 10 and 60 feet the microadjustment required follows a linear progression from 0 to -13. But at or near infinity it will miss the focus unless I dial the adjustment back to -10 or less. Now for the catch. When I attach the 1.4x extender it is dead on focus at all distances with no adjustment at all!
I'd love to have a Canon engineer explain this.
Since Canon has taken the ingenious descision to orphan the 200 1.8 I want to know what inside this lens is adjusted for autofocus corrections. I'll get the tools and take it apart myself if I have to - no problem.
The 35L also requires +7 at up to 8 ft. and +12 at 15 ft. keeping in mind I want to shoot at f1.4 to f2 with this lens and still have a subjects eyes in focus and not her ear

Sep 10, 2008 at 01:13 PM

Mike1
Offline
Upload & Sell: Off

p.2 #5 · 1Ds MkIII - AF Microadjustments

I think these "modern" zoom lenses are not parfocal like the older manual focus lenses and the engineering dept have overlooked that maybe due to time constraints. As far as primes, I think the design of the lens in correlation to distance scale has also been overlooked as well... As photographic equipment gets more complex, one would expect the lens designs to be the same, but it's not always what it should be, even though it looks good on paper. Ah... engineering at its worst.

Sep 10, 2008 at 02:06 PM

mdbassman
Offline
Dedicated FM
Upload & Sell: On

p.2 #6 · 1Ds MkIII - AF Microadjustments

Any recent(within 2-6 months) on this? I have tried and tried the AF MA and it is NEVER the same at any distance!!!!
My 300mm f/2.8 IS is "dead on" anywhere but every other lens is off.
Any speculation or newer good tests??
dan

Jun 12, 2009 at 01:21 PM

jerrykur
Offline
Dedicated FM
Upload & Sell: On

p.2 #7 · 1Ds MkIII - AF Microadjustments

mdbassman wrote:
Any recent(within 2-6 months) on this? I have tried and tried the AF MA and it is NEVER the same at any distance!!!!
My 300mm f/2.8 IS is "dead on" anywhere but every other lens is off.
Any speculation or newer good tests??
dan

My results are 100% repeatable. But this is with a 5DMK2. With the lenses adjusted they are all spot on at 20X focal length. I am using a one ope Tape's adjustment targets.

Jun 12, 2009 at 02:28 PM

stanj
Offline
Dedicated FM
Upload & Sell: On

p.2 #8 · 1Ds MkIII - AF Microadjustments

eonflux wrote:
By the way...Is the Canon 1Ds Mk III the first and only camera to have this feature? Do any of the other Canon models allow you to perform this mod...what about Nikon?

Canon 1D3, 1Ds3, 5D2, 50D
Nikon D300, D700, D3, D3X

Maybe some of the new, "lesser" cameras too but I haven't been keeping track of these.

BTW, my MA on my 1Ds3 are way less spread than yours. I think it would be prudent to have the lenses calibrated.

Jun 12, 2009 at 03:55 PM

Paratima
Offline
Upload & Sell: Off

p.2 #9 · 1Ds MkIII - AF Microadjustments

Auto-focus is a crutch that you shouldn't really need anyway. Not much more than a fancy marketing ploy to sell more lenses and cameras. It's a fad that will die off in a few years.

Eschew AF. Train yourself in the way of MF and your world will be a happier place.

Jun 12, 2009 at 04:20 PM

UCSB
Online
Dedicated FM
Upload & Sell: Off

p.2 #10 · 1Ds MkIII - AF Microadjustments

eonflux wrote:
I finally received my RRS L-Bracket in the mail yesterday. With that said, I thought it was time to see what this camera can do (1Ds MkIII). Of course, I had to make sure my lenses were tack sharp. In order to do that, I had to find out what the "AF Microadjustments" was all about.

One word...WOW!!! I thought my lenses were sharp and sweet before. Shoot, based on my results, I should have thrown the lenses away. Of course, I would never throw them away. That's like asking a crack head to give up his supplier. In short, these lenses are far sharper now than ever before (except for the 85mm).

In the end, I made the following adjustments...Tell me what, if any, were your adjustments? I'm curious to see what others are experiencing.

Canon 14mm f/2.8 MkII (at f/8)
+20

Canon 50mm f/1.4 (at f/8)
-10

Canon 85mm f/1.8 (at f/8)
0 (no adjustment needed)

Canon 135mm f/2 (at f/8)
-20

Canon 135mm f/2 (w/ 1.4x MkII) (at f/8)
-10

Canon 24-70mm f/2.8 (at f/8)
+5

Canon 70-200mm f/2.8 (at f/8)
-20

Canon 70-200mm f/2.8 (w/ 1.4x MkII) (at f/8)
-20

Tamron 28-75mm f/2.8 (at f/8)
-20

By the way...Is the Canon 1Ds Mk III the first and only camera to have this feature? Do any of the other Canon models allow you to perform this mod...what about Nikon?

Thanks,
Karl

Karl,

All of the +20 and -20 adjustments seem to indicate a problem with your micro adjustment approach or equipment. Other posters have brought up other problems (MA only works at some distances, what distance to use when MA'ing, etc.) ... these can also be caused by a bad approach to MA.

Here is a link to a procedure that can be used to get accurate results: http://www.precisioncaps.com/training_af_micro_adjust.html

Good luck,
Bill.

Jun 12, 2009 at 05:25 PM

mdbassman
Offline
Dedicated FM
Upload & Sell: On

p.2 #11 · 1Ds MkIII - AF Microadjustments

Thanks Bill, this was the question I was addressing..broad variation in results. Thanks for the link!
Dan

Jun 13, 2009 at 01:48 PM

xrayvision
Offline
Upload & Sell: Off

p.2 #12 · 1Ds MkIII - AF Microadjustments

Paratima wrote:
Auto-focus is a crutch that you shouldn't really need anyway. Not much more than a fancy marketing ploy to sell more lenses and cameras. It's a fad that will die off in a few years.

Eschew AF. Train yourself in the way of MF and your world will be a happier place.

Yeah,right. Unless you are shooting an 85 at f1.2 on a full frame 20mp+ camera. Back when my eyes were 20/15 (exceeding 20/20) I might have been able to accomplish the exact focus in that setup using my eyes. Now? my eyes are down to 20/30 or so. I'm getting old and then I'll die... In the meantime I need autofocus as a crutch to stand, not something to lean on

When they start using the pixels sites on the sensor as the autofocus mechanism things will improve.

Jun 13, 2009 at 02:15 PM

1 2 end
FM Forums \| Canon-mount SLRs \| Join Upload & Sell 1 2 end