fredmiranda.com
Login

Dot-Tune: Autofocus Fine Tuning in under 5 minutes

  
 
Todd Moon
Offline
Details
p.19 #1Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Yes, 6D, and no, never.
Sep 05, 2013 at 08:26 AM
outlawyer
Offline
Details
p.19 #2Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Is there some precise location on the ML site for DOT tuning 6D? Just not seeing it. Snapsy?
Sep 05, 2013 at 08:29 AM
Todd Moon
Offline
Details
p.19 #3Dot-Tune: Autofocus Fine Tuning in under 5 minutes
No, it's a feature of the software once you install it in your camera.
Sep 05, 2013 at 08:49 AM
Richard Nye
Offline
Details
p.19 #4Dot-Tune: Autofocus Fine Tuning in under 5 minutes
mark for future reference
Oct 29, 2013 at 01:16 PM
x-box
Offline
Details
p.19 #5Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Hi Can anyone suggest please?
I got a Zeiss manual focus lens for my 5D mark III, and after using the DotTune method, the first steady point is +16 toward the + side, after using the slightly defocus method to workaround, i found the Steady green dot range is 14, so the mid point is 7 and that brings the exact point to be at +16 plus 7 = +23 which is out of the AFMA range.
what shall I do in this case? should I set at +16 or +20 or send the lens back to manufacture to calibrate within the range? but this is a manual focus lens, so, I really dont know what the best option now.

Many thanks for any advice

Henry
Nov 06, 2013 at 06:03 AM
Kipliq
Offline
Details
p.19 #6Dot-Tune: Autofocus Fine Tuning in under 5 minutes
I read ML has DotTune, cant find anything about my 7D having the option in ML. I'm gonna give this a shot to help with my Sig 35mm 1.4 art if not it going back to Amazon
Nov 07, 2013 at 01:26 PM
snapsy
Online
Details
p.19 #7Dot-Tune: Autofocus Fine Tuning in under 5 minutes
x-box wrote:
Hi Can anyone suggest please?
I got a Zeiss manual focus lens for my 5D mark III, and after using the DotTune method, the first steady point is +16 toward the + side, after using the slightly defocus method to workaround, i found the Steady green dot range is 14, so the mid point is 7 and that brings the exact point to be at +16 plus 7 = +23 which is out of the AFMA range.
what shall I do in this case? should I set at +16 or +20 or send the lens back to manufacture to calibrate within the
...Show more →

I helped Henry out over PM. I suggested sending the lens in for calibration if it's under warranty, or otherwise use +20 since that's relatively close to the center of the tuning range.
Nov 07, 2013 at 01:32 PM
gschlact
Offline
Details
p.19 #8Dot-Tune: Autofocus Fine Tuning in under 5 minutes
x-box wrote:
Hi Can anyone suggest please?
I got a Zeiss manual focus lens for my 5D mark III, and after using the DotTune method, the first steady point is +16 toward the + side, after using the slightly defocus method to workaround, i found the Steady green dot range is 14, so the mid point is 7 and that brings the exact point to be at +16 plus 7 = +23 which is out of the AFMA range.
what shall I do in this case? should I set at +16 or +20 or send the lens back to manufacture to calibrate within the
...Show more →

Henry-
your writeup is a bit confusing, how did you figure the range is 14 for this manual focus Zeiss? Are you basing it off of other 50mm at the same distance? ANyway, +20 is closer to +23 which would be better than your +16 focus edge. BUT, being that the Zeiss is positioned to work on the Canon with AF confirm, I would suggest sending back to them to better calibrate and tell them that it is naturally and heavily front focusing.

ALSO - one related piece of advice. In Canon AF systems, even for fixed focal length and distance to subject, you will get differenet MFA values under different types of lighting!!! Flourescent will create back focused results while Incandescent will be front focued, and Sunlight in between. ;-(. So, if you sent to Zeiss, consider including description of lighting.
Nov 07, 2013 at 01:48 PM
x-box
Offline
Details
p.19 #9Dot-Tune: Autofocus Fine Tuning in under 5 minutes
gschlact wrote:
x-box wroteHi Can anyone suggest please?
I got a Zeiss manual focus lens for my 5D mark III, and after using the DotTune method, the first steady point is +16 toward the + side, after using the slightly defocus method to workaround, i found the Steady green dot range is 14, so the mid point is 7 and that brings the exact point to be at +16 plus 7 = +23 which is out of the AFMA range.
what shall I do in this case? should I set at +16 or +20 or send the lens back to manufacture to calibrate within the range? but this is a manual focus lens, so, I really dont know what the best option now.

Many thanks for any advice

Henry
Henry-
your writeup is a bit confusing, how did you figure the range is 14 for this manual focus Zeiss? Are you basing it off of other 50mm at the same distance? ANyway, +20 is closer to +23 which would be better than your +16 focus edge. BUT, being that the Zeiss is positioned to work on the Canon with AF confirm, I would suggest sending back to them to better calibrate and tell them that it is naturally and heavily front focusing.

ALSO - one related piece of advice. In Canon AF systems, even for fixed focal length and
...Show more →

Many thanks Gschlact

To figure out the steady green dot range I use the workaround method:
http://www.dpreview.com/forums/post/50775939


Very interesting regarding the differenct light conditions, I use one 400W Halogen light to light up the test chat - may give it a try under daytime normal lighting condtion - has to be a weekend, as when I got home weekdays, its completely dark.

Nov 07, 2013 at 02:35 PM
gschlact
Offline
Details
p.19 #10Dot-Tune: Autofocus Fine Tuning in under 5 minutes
x-box,
Halogen should actually have been very neutral with even color specturm in its white light so I wouldn't bother trying under other lighting.

-Guy
Nov 07, 2013 at 03:13 PM
 


Search in Used Dept. 

Kipliq
Offline
Details
p.19 #11Dot-Tune: Autofocus Fine Tuning in under 5 minutes
I'll test the manual way. How bright of a light setting would be best? Afternoon sun? I'll setup my charts in my year if so. The ML kinda scary with people bricking their bodies.
Nov 07, 2013 at 06:11 PM
gschlact
Offline
Details
p.19 #12Dot-Tune: Autofocus Fine Tuning in under 5 minutes
one governing suggestion to any MFA is plenty of light so that you do not make the phase AF struggle.
Nov 08, 2013 at 01:25 PM
Mitchell Carter
Offline
Details
p.19 #13Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Kipliq wrote in part:
The ML kinda scary with people bricking their bodies.


Any people you can name, or sources you can link to?
Nov 08, 2013 at 01:55 PM
Kipliq
Offline
Details
p.19 #14Dot-Tune: Autofocus Fine Tuning in under 5 minutes
I found them on the magic lantern site. I was reading and looking for data on the 7d alpha build.
Nov 08, 2013 at 06:32 PM
Mitchell Carter
Offline
Details
p.19 #15Dot-Tune: Autofocus Fine Tuning in under 5 minutes
So... no link, no one you know, no specific incidents, just a vague I-read-it-at-ML? Sorry; doesn't scare me.
Nov 08, 2013 at 07:00 PM
bushwacker
Offline
Details
p.19 #16Dot-Tune: Autofocus Fine Tuning in under 5 minutes

Okay guys... what's the reason why you have to set it at MAX Aperture when doing AF micro-adjustment?

Nov 24, 2013 at 06:54 AM
bushwacker
Offline
Details
p.19 #17Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Mitchell Carter wrote:
So... no link, no one you know, no specific incidents, just a vague I-read-it-at-ML? Sorry; doesn't scare me.



True!!! it's really funny when I see people say "I read somewhere......."
Nov 24, 2013 at 06:58 AM
Ian.Dobinson
Offline
Details
p.19 #18Dot-Tune: Autofocus Fine Tuning in under 5 minutes
bushwacker wrote:
Okay guys... what's the reason why you have to set it at MAX Aperture when doing AF micro-adjustment?



thinnest DOF . gives you the greatest accuracy of getting the best point of focus .

of course that could be skewed when you have a lens that gives stop down focus shift
Nov 24, 2013 at 07:44 AM
snapsy
Online
Details
p.19 #19Dot-Tune: Autofocus Fine Tuning in under 5 minutes
bushwacker wrote:
Okay guys... what's the reason why you have to set it at MAX Aperture when doing AF micro-adjustment?


The PDAF system always uses the lens at its maximum aperture when performing phase detection for focusing, so setting the lens to a smaller aperture for the VF confirmation of DotTune will have no effect on the results. If however you use a smaller aperture during the initial CDAF/Live View focus of DotTune then spherical aberration (focus shift) correction will be baked into the tuning result, which most users probably wouldn't want since it will negatively affect the accuracy when shooting wide-open. I actually tune some of my lenses that way so it's a valid technique but only if the photographer understands the implications.
Nov 24, 2013 at 08:35 AM
bushwacker
Offline
Details
p.19 #20Dot-Tune: Autofocus Fine Tuning in under 5 minutes

Ian & Snapsy:


That's what I am thinking the focus shift... like how do I compensate for focus shift if I set my lens at 1.4 then focus shifts around f2, f2.8 & f4.
Nov 24, 2013 at 08:57 AM


FM ForumsCanon ForumJoin Upload & Sell
  
 

You are not logged inLog inRegister

Switch to mobile view