John Gerlach Loc: Island Park, Idaho

Things keep changing for me as I continually evolve my photo techniques I like to use. Though often necessary for wildlife, I use autofocus with AF microadjusted lenses and camera combos and that helps a lot for getting sharp focus. I have found that all of my Canon lenses required some AF microadjustment value between - 3 and - 9 to hit sharp focus, but autofocus still can vary a bit from shot to shot. I use manual focus using the 10X magnified live view image with super results for everything that holds still. And lately, I have heard and tried using autofocus by touching the LCD in live view. I heard that this eliminates the microadjustment problem just like it does on mirrorless cameras. Not having a mirrorless camera yet, I wonder if those that do also find their focus is right on. I ran a small autofocus test where I did five shots by using autofocus on the LCD and manual focus using the magnified live view image and both methods produced the same sharpness. But, I don't want to draw any conclusions from such a small test. Has anyone else testing autofocus in live view and found it to be accurate? I have not seen a compelling reason to use mirrorless yet, but accurate autofocus without having to microadjust autofocus is appealing.

For nearly all landscape and close-up images, I rely on manual focus using the magnified live view image. Here is a 5 shot focus stack where I changed the focus distance manually, but I could have done it using autofocus by touching the LCD set to S

(Download)

burkphoto Loc: High Point, NC

John, I use a Lumix GH4. Any focus errors are mine, either because I chose the wrong focus mode, or used the camera incorrectly, or exceeded its ability to track a moving subject.

Most of the latest mirrorless cameras focus quite well. The latest from Panasonic (G9) and the Canon FF mirrorless (R) are both extremely fast, if not the top two fastest in the world.

There are two types of focusing systems. Phase detect AF is generally better at tracking motion. Contrast detect AF is best at single-point AF.

Mirrorless cameras DO NOT require any sort of lens to camera calibration. Because the same sensor plane is used for both focus and image capture, there is nothing to get out of alignment. All your lenses will focus equally well, so long as they support native AF with your camera.

Manual focus on mirrorless cameras often has the assistance of "focus peaking." The EVF also may magnify a part of the subject in the finder, so you can see the focus better.

lamiaceae Loc: San Luis Obispo County, CA

All good questions. I really don't know (yet). I mainly shoot Close-ups and Macro when I'm not shooting landscapes. More Close-up & Macro I am usually manually focusing, often with vintage manual lenses with a DSLR. The few times I've tried it, LV and Focus Peaking does work. Better or not than my own Manual Focusing I could not yet say. The one single-lens Digital Rangefinder Mirrorless Camera, a Fuji X100T does provide manual focus OVF, and EVF/back Screen Auto Focus with Peaking that does work. I've found this slow thus far, but this is not the ideal camera for close-up work, having a 23mm lens for a APS-C Sensor. The similar Fuji Full MILC with a 35mm, 50mm, or 60mm lens X-Pro2 camera would be a better test for me.

I've never found I've needed to adjust the AF on my Pentax Cameras or AF Lenses. Most of my many Pentax Lenses are vintage and manual though (some support full AE but not AF).

DaveO Loc: Northeast CT

John, are you "focusing" in Yellowstone again this winter??

John Gerlach Loc: Island Park, Idaho

Yes, I am leading four five day photo tours in Yellowstone from mid Jan to mid February.

John Gerlach Loc: Island Park, Idaho

Sounds good. This is what I am finding on the web and glad you see the same results. It is good to know I can rely on autofocus on the LCD to be accurate. It speeds up focus stacking for simple subjects that don't require many different focus points.

DaveO Loc: Northeast CT

Have fun! Someday when we're old we shall do a winter tour.

I found your site: https://www.gerlachnaturephoto.com/workshops

bsprague Loc: Lacey, WA, USA

"The latest from Panasonic (G9)..."

I wish you would quit bragging up that camera!

speters Loc: Grangeville/Idaho

I have yet to find a Canon lens that I have to micro-adjust, so far never had to. I always prefer manual focus for critical shots, its just more precise, although I do rely on af for any sorts of action shots!

burkphoto Loc: High Point, NC

See, I can, because I'm GAS-proof on that one. It isn't quite the video champ I need. Now, the GH5 is another story...

TriX Loc: Raleigh, NC

And I have only found 1 Canon lens out of 8 that did not benefit from microfocus adjustment, but I know this is a contentious subject, and I have no illusions that I will convince anyone who is in the “MFA unneeded” camp to try it.

Cheers

Strodav Loc: Houston, Tx

I have done a fair amount of focus testing with Nikon bodies and Nikon, Tamron and Sigma lenses and have found that I get the sharpest results possible in LV (if you use good technique) and can then compare AF shots against LV shots. LV uses a different method to achieve focus than AF uses. I usually find AF is a bit softer and can be tweaked using AF fine-tune to walk it in. You are right in saying AF is not consistent, but is a random variable. If you take a number of shots in AF (tripod, remote trigger, wide open aperture, ...,) by moving the focus ring off of focus a bit then taking the shot you will see that some shots are a bit forward focused and some shots a bit back focused from the average focus point. Its not much, but there is a difference, which is masked by closing down the aperture increasing DOF. Note that there is only 1 focus plane and sharpness drops off slowly around the focus plane. Of course it drops off faster around the focus plane with a small DOF (open aperture) and slower with a larger DOF (stopped down) until diffraction happens.

imagemeister Loc: mid east Florida

Yes, and deservedly so ! ......the 80D is very adept (fast and accurate) at focus on the LCD ( mostly for video or using the articulating back)- and full mirror less are better !

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John Gerlach Loc: Island Park, Idaho

Thanks all. It does seem to be that live view AF is more accurate than AF in the old way of shooting where you look through the viewfinder. I like that. And I am surprised to hear some shooters don't find AF microadjustment helpful as I have yet to test a Canon lens that has the best focus using the default 0 setting at the longest focal length on a zoom lens. It could happen, but I am 0 for about 25 so far as I test my client lenses too when they want me to. Usually they aren't off much, but some AF microadjustment has vastly improved my sharpness. Trust me, when -9 is the best setting for my Canon 100-400mm lens at 400mm, the 0 setting is significantly not sharp. My article on microadjusting is found on my web site.

John Gerlach Loc: Island Park, Idaho

Exactly what I find is autofocus does vary a little and stopping down masks the error, but often in wildlife photography I have to shoot wide open or close to that and then the depth of field doesn't hide the error. My answer is to shoot the same shot, but make the lens focus a couple of times. Shoot a few images, refocus on something else, then focus on the target again and shoot a few more.