p.33 #1 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
snapsy wrote: Canon version of technique
1. With the camera mounted on a tripod, enter Live View and establish critical focus on a high-contrast subject over the center point. Exit Live View.
2. Set the lens to MF (Manual Focusing). Be careful not to jostle the focus ring when you move the switch - you don't want to alter the focus you established in step #1.
Will it be OK to swap steps 1 and 2? That means; 1) Set the lens to MF. 2) Manually focus in LV and then exit LV.
p.33 #6 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Has anyone does much experimenting to see how consistent their contrast detection focus is on their camera?
For example you do the normal dot tune method and get a range of -12 to 4 for a specific camera /lens combo. Then you do another contrast focus for the same lens/camera combo this time you might get -10 to 6. These are not too far off. However sometimes I have had the range shift 8 or more.
p.33 #7 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
SeattleBirdMan wrote:
Has anyone does much experimenting to see how consistent their contrast detection focus is on their camera?
For example you do the normal dot tune method and get a range of -12 to 4 for a specific camera /lens combo. Then you do another contrast focus for the same lens/camera combo this time you might get -10 to 6. These are not too far off. However sometimes I have had the range shift 8 or more.
Has anyone else seen that before?
Canon's contrast-detect precision is pretty good but there's still enough variance to significantly effect potential tuning. I generally MF in LV using a magnifying loupe when I DoTune. Roger did a precision test of CDAF as part of his PDAF precision tests - you can see the results here. In my experience, Nikon's CDAF has much worse precision than Canon - in fact Nikon's is so bad that on newer bodies like the D750/D810, PDAF is more consistent than their CDAF.
p.33 #8 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Thanks for the response Snapsy. I do use Canon cameras. Interesting suggestion to use manual focusing. I'd have to practice that. I'm not sure if I could be very accurate on manual focus even using 10x view.
p.33 #9 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
I usually check the range three times. Usually, all agree. Sometimes one reading is significantly off but not reproducible.
SeattleBirdMan wrote:
Has anyone does much experimenting to see how consistent their contrast detection focus is on their camera?
For example you do the normal dot tune method and get a range of -12 to 4 for a specific camera /lens combo. Then you do another contrast focus for the same lens/camera combo this time you might get -10 to 6. These are not too far off. However sometimes I have had the range shift 8 or more.
p.33 #10 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
SeattleBirdMan wrote:
Has anyone does much experimenting to see how consistent their contrast detection focus is on their camera?
For example you do the normal dot tune method and get a range of -12 to 4 for a specific camera /lens combo. Then you do another contrast focus for the same lens/camera combo this time you might get -10 to 6. These are not too far off. However sometimes I have had the range shift 8 or more.
Has anyone else seen that before?
Yes, that's why I quit using the Dot Tune method. But I have Canon equipment. For Nikon, apparently, it works much better.
p.33 #12 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Obviously, my mileage varies. FoCal is a pain to use, but since version 2.0 has been released, I have consistent, reliable MFA. Maybe it is just me. But most of my photography friends no longer use Dot Tune either. Of course, we all have Canon bodies. I wish Dot Tune was reliable (for me) because it is a simple method. Glad you're satisfied with Dot Tune.
p.33 #13 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Thanks Snapsy, bookmarked this a few months ago when it trickled to the top again. Got around to trying it today. Worked great for me with a 1Dx, 70-200 II, 85 1.8 and 50 1.8. All done in under 30 minutes. Would have taken me much longer with Focal. Not a knock against Focal as it does many other things also.
p.33 #14 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
snapsy wrote:
Roger did a precision test of CDAF as part of his PDAF precision tests - you can see the results here. In my experience, Nikon's CDAF has much worse precision than Canon - in fact Nikon's is so bad that on newer bodies like the D750/D810, PDAF is more consistent than their CDAF.
Wow, that is very surprising?! That just throw something I assumed about CDAF out the window.
p.33 #18 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
Dumb question. If you dot tune 3 lenses obviously they will have different settings. Does your camera (6d/70d) "remember" the settings automatically or do you have to set something up like a custom setting and trigger that each time you use a different lens.
p.33 #19 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
pointbob wrote:
Dumb question. If you dot tune 3 lenses obviously they will have different settings. Does your camera (6d/70d) "remember" the settings automatically or do you have to set something up like a custom setting and trigger that each time you use a different lens.
Yes, there is a setting to save adjustments for each lens or use the same adjustment for all lenses. Just make sure it is set appropriately.
p.33 #20 · Dot-Tune: Autofocus Fine Tuning in under 5 minutes
SeattleBirdMan wrote:
Yes, there is a setting to save adjustments for each lens or use the same adjustment for all lenses. Just make sure it is set appropriately.
Thanks: do you know where in the menu that would exist?
I only suggest AF first for those who want to use CDAF in LV rather than having to manually focus in LV.