5dmkiv focusing Microadjustments

[Gino-Mazzaferro]

I've been watching youtube vids about microadjustment for autofocusing. From what I understand, the focusing process is different in liveView. Is Liveview more accurate or not (in autofocus mode)? Would I benerfit in going through the process of the microadjustments for my different lenses for liveView or would it only help in viewfinder focusing? Thanks

[RobertTheFat]

---

@Gino-Mazzaferro wrote:

I've been watching youtube vids about microadjustment for autofocusing. From what I understand, the focusing process is different in liveView. Is Liveview more accurate or not (in autofocus mode)? Would I benerfit in going through the process of the microadjustments for my different lenses for liveView or would it only help in viewfinder focusing? Thanks

---

It helps only in viewfinder focusing. In principle at least, you don't need it in live view. Because the focusing is being done directly on the sensor, there's nothing to adjust.

[kvbarkley]

The point is to calibrate the focus chip - which has a different optical path length than the sensor - to the sensor. Live view defeats the purpose of that.

[Gino-Mazzaferro]

Thanks. So theoretically the autofocus in liveview and through the viewfinder could be slightly different if the lens/body combination needs microajustement? 

[kvbarkley]

Yes. Autofocus in live view should theoretically be perfect, but there can be some tuning of the control loop required for perfect autofocus.

[Waddizzle]

---

@Gino-Mazzaferro wrote:

Thanks. So theoretically the autofocus in liveview and through the viewfinder could be slightly different if the lens/body combination needs microajustement? 

---

Just go out and use the camera.  Stop watching so many YouTube videos.  There are quite a few quacks out there belching nonsense.  The only really good YouTube video on the topic of AFMA is the " Dot Tune Method " video.

Making AFMA only affects viewfinder focusing.  Making the adjustments is not as simple and straightforward as some of the videos make it out to be.  Hardly any of the videos point out the pitfalls and common mistakes that you can make.  One of the biggest mistakes is trying to make adjustments in the first place.

Making adjustments can test your skill as a photographer because you need to take numerous shots, not just a handful.  You need for those sample shots to be identical from one shot to the next.  The videos do not tell you take several shots and average the results.  The videos do not point out that lighting conditions can make a world of difference.  

The videos fail to point out the impact of what type of focusing target you use   Size and distance matters.  Do not buy one of those overpriced calibration targets that are the size of an 8x11 sheet of paper, and then try to use it to calibrate a super telephoto lens from 50 yards away.

It is far easier to make a bad set of adjustments than to make a correct set of adjustments.

[Gino-Mazzaferro]

Thanks for the feedback. 

[Waddizzle · Accepted solution]

---

@Gino-Mazzaferro wrote:

Thanks for the feedback. 

---

You're welcome.  Not every photo you take is going to be tack sharp.  Some lenses do not focus accurately enough to make the exercise of AFMA worth the effort.  These lenses are typically the budget priced lenses.

Canon's L glass seems to rarely need any AFMA adjustments, although my 70-200 did seem to need it on the short end, where it appeared to be back-focusing.  I did not buy it from either of my usual online sources for Canon gear: The Canon Online Store and B&H Photo Video in NYC.

[ebiggs1]

"Just go out and use the camera."

You ARE the man!  Could have not said it better. Outstanding!