looking for better way to adjust microfocus

I have a 50D and am interested in doing a microfocus adjustment on it, to ensure that it is working perfectly with my 400mm lens.

When I have read about doing this, it seems that every method involves setting the body and lens up and attempting to focus on some actual, physical, tangible object - then take images at several different settings, download, and visually examine the images. Or, to use Live View and actually look at the images and try to visually determine which is in sharpest focus. I am not sure I trust my eyeballs so much.

So, I am wondering if there is some way to do a microfocus adjustment in which I do not have to make a judgement call about what looks sharpest to me. Is there some way the camera can just confirm sharpest focus? Or some computer program that can just "look" at images, and determine the sharpest one?

My concern is that I may end up with a bunch of very sharp images, but that one of the settings will result in images that are a tiny bit sharper than the others - and that I will simply not be able to "see" the difference without equipment that is much more sophisticated than my eyeballs. Plus, I simply do not like having to make discretionary decisions, because there remains a chance that I may make the wrong one.

I trust technology a lot. I do not trust my eyeballs and my brain to work together well enough to make the best decision. Any advice or experience would be appreciated.

Tom, I assume you've looked at Focal? http://www.reikan.co.u​k/focalweb/

It's pretty good unless you're a 5D3 or 1DX owner...

Hi

I have used a piece of software called FoCal to automatically micro adjust and find it fairly easy and paint less. Take a look at http://www.reikan.co.u​k

Regards
Steve

FocusTune works untethered. I have no experience though.

http://michaeltapesdes​ign.com/focustune.html

FoCal.

5dc, no tethering live view option?

Tom,
Are you unsatisfied with your images ? ? ? If so don't worry as wildlife shooters shoot stepped down a lot anyway. If you have a 400/300 2.8 and wish to shoot wide open that's different though..........

I'll chime in with Focal as well. Although I have had a lot of luch shooting a ISO12233 chart. It wont tell you if it's front or back focused, at least right away, it takes a bit of experimenting, but it does tell you when you have reached the point of highest resolution. Example below.

Tom,
You should have good luck since you shoot with a prime.
I have considered MFA with my 7d but I use a 100-400 so I'm not sure how much it will help
over the whole focal range.

Todd Lambert wrote in post #15492835
Tom, I assume you've looked at Focal? http://www.reikan.co.u​k/focalweb/

It's pretty good unless you're a 5D3 or 1DX owner...

What's good when using a 5d3?

nccb wrote in post #15493858
What's good when using a 5d3?

FoCal is still good.. it will still do the automated tests (in the Pro version) it just won't automatically set the values for you. You have to go into the custom functions and choose the value manually. For other bodies is automatically sets that value after the test is run (and if you agree with the results). That's the only function not available for the 5D3 vs other bodies.

I have 5dmk3 and plus version and it works like mentioned above. Maybe Pro has some more things.

Er, has anybody mentioned FoCal yet?

what does that imply? Every prime I have MA'd required adjustment. Most were back focusing by +5 or more.

If you want to use a focus chart, it will work, but you need to play with the adjustments at first as "out of focus" doesn't determine front or back focusing. I will say, after using LensAlign to MA 8 or 9 lenses, all were back focusing except for one.

Personally, I like using LensAlign. It's easy to setup and goes quickly if you have 2 tripods (1 for camera, 1 for tool) and a bit of space. Basically it has a flat focal plane that is inline with a long ruler with a number scale, objects and slashes. Once aligned, you take a test shot and then look at the ruler to see where focus lies. It gives you a good starting point and it's fairly clear what is in focus and what is not because you are shooting with a low depth of field.

Gregg.Siam wrote in post #15495437
what does that imply? Every prime I have MA'd required adjustment. Most were back focusing by +5 or more.

I think it implies that primes require a single MA value, whereas zooms often exhibit different degrees of focus misalignment depending on the focal length one uses.