Mirrorless Autofocus

[Bill Pierce]

A friend of mine who is a staunch rangefinder user asked me what was the big deal about these new mirrorless cameras. As a Leica user he was not impressed that the mirrorless cameras were small and quiet. There are a lot of mirrorless cameras out there, varied in features and quality. The only common “big deal” that I could think of was the focusing accuracy inherent in the autofocus and, if you have good eyes, the manual focus. That’s simply because they are cameras that actually use the image on the sensor to determine focus (and, in the majority of cases these days, use both phase detect and contrast for auto focus).

Other cameras can read off the sensor, but not as easily. Even when film was the only recording medium, Leitz acknowledged the limitations in rangefinder focusing especially with high aperture and longer focal length lenses. Those limitations have expanded and become more obvious as sensors have improved in their ability to capture fine detail. But the digital rangefinder camera’s magnified LCD and digital Visoflex focusing can solve that problem - just not its rangefinder.

And DSLRs offer a similar solution. Throwing up the mirror and using the rear LCD to focus returns judging the focus to the actual sensor rather than a separate autofocus sensor that gets its image from a sub-mirror.

In other words, you can get the focusing accuracy of a mirrorless camera with rangefinders and DLSRs by converting them to mirrorless cameras. It’s just not anywhere as quick and convenient as using a mirrorless camera to begin with but may be important in certain shooting situations.

Your thoughts? Mirrorless or the work arounds?

 

[Jamie Pillers]

Not to split the topic here, but another big deal benefit of using mirrorless is that the EVF or LCD displays a close approximation of the end result. I use Fuji gear and enjoy using their film simulations. The EVF gives me a good representation of what the simulation will look like. Pretty cool to see the scene as B&W, for example.

 

[Darthfeeble]

I've gone totally mirrorless but for the M9 and R-D1 that I use very rarely. Mostly Fuji cameras and one Nikon. One of the things that I enjoy is the ability to see in B&W in the viewfinder. It helps me compose better and I need that help.

 

[BillBingham2]

I look at DSLRs now as soon to be dinosaur, a 4x5 Crown Graphic in group of Nikon Fs. I never thought about B&W on an EVF, damn, another great idea. Especially if you can set up a couple of control buttons to flip a red, yellow or green filter conversion quickly.

Nikkor Z mount wide glass look HUGE, yes it's fast, yes it's great, and yes it's also very expensive. Prices of new CV glass and the quality of old glass from many sources has spoiled me.

Mirrorless opens up the world of digital to a lot of old glass for just about any source. Something DSLR could.

Leica digital bodies, even used are still in the stratosphere for me. I'm not sure there's enough of a reason to save my shekels up to move back that way. Fuji is not perfect, but it's flexible and good enough for me.

B2 (;->

 

[ColSebastianMoran]

My take (with Sony mirrorless)
- Mirrorless Autofocus with current lenses is great
- Mirrorless works great with legacy adapted manual focus lenses (focus peaking works very well)

 

[Rayt]

Mirrorless means I can use an M lens without the hood blocking a corner of the viewfinder, or not misfocus a fast lens when focusing with the RF patch in the middle and then recompose, or manually focus an SLR lens in the dark etc. I really like the M10 with both an optical viewfinder and an EVF.

* just saw it was mirrorless Autofocus. Nevermind!

 

[Out to Lunch]

Mirrorless, autofocus and tracking is just another step-up. Not very long ago, people were debating whether an in-camera light meter was just a fad. La Nave va. Cheers, OtL

 

[jsrockit]

I like being able to see highlight over-exposure in my viewfinder...that’s the real big change for me.

 

[Dogman]

The problem I have with most mirrorless cameras is the EVF. I use Fuji XPros and a couple of old X100s cameras solely for the OVFs and the nice bright view the provide. EVFs, for me, looks incredibly synthetic and not at all like the subject I'm photographing. I know many like the way the camera translates the subject to what it sees and what the final image will become. However, I really prefer to view the actual subject, not an interpretation of how it will look. I'll interpret it later when I edit and print it.

The other problem I have with EVFs is how difficult it is for me to see them in bright light. My eyes are very sensitive to light. Combined with the rather dim image of the EVF in bright light, with loss of detail in shadows and highlights, it's extremely difficult for me to use them. It's not quite as bad as using the LCD in bright sunlight but it's pretty close. A neighbor came by a few months ago with his new Nikon Z7. I tried using it and it was too dim for my eyes while viewing outside. Couldn't see detail.

I will admit that the EVF can be helpful under very low light conditions. That's when I can flip the switch on the XPro and X100 and find the EVF useful. But I would hate to depend on it as the only viewing source. I sorta now use my Fujis as I used Leicas in the past. As supplemental cameras with SLRs. After using various mirrorless cameras and settling on the XPro and X100, I decided to try using an SLR again. I discovered I loved using the thing and I've since reverted mostly to Nikon DSLRs. I enjoy using them even though they are heavy and big and have their own set of negatives. After using them for a few months, I pulled out my Fuji XT1 that I had not used in over a year and tried shooting with it. For my eyes, the image looks like video and unnatural. Gimme an SLR and a clear window viewfinder and I'm much happier.

Autofocus? I suppose mirrorless would have the advantage here. I have to adjust the AF for my Nikon lenses on each Nikon body while that's not an issue with the Fujis. Still, both seem accurate to me and the DSLR still appears to have an advantage in some areas of AF such as tracking. I haven't kept up with it so things might have changed but sports and wildlife shooters (I'm not one) still like DSLRs for AF speed and tracking. I'm good with AF with the Nikons and the Fujis. Either or both are more accurate and faster than I've ever been able to manually focus so AF is a win for me in all respects.

 

[Cascadilla]

I haven't bought a mirrorless camera yet, and I'm not in a hurry to do it since I know that the implication for me is a new set of lenses. I do use live view a lot in my studio with my DSLRs and love the ability to zoom in for accurate manual focusing, with focus peaking being very useful. It isn't my Schneider 8x loupe on the ground glass of my 4x5 but it's good. For field use I still prefer the optical finder--brightness for live view is an issue with my cameras in bright light and I'm not about to bring back my focusing cloth to use with a DSLR.

 

[Ricoh]

“Your thoughts? Mirrorless or the work arounds?“

Mirrorless and their native lenses are designed as a system. The system solution is highly tuned.

Work arounds, such as mirrorless and manual focus lenses are a second best even with focus peaking (my experience).

Leica M240 digital rangefinder is really clunky when operated as a mirrorless. With a screensaver in place the contrast is diminished, and with the EV-2 the delayed screen update is off putting, plus the shutter needing to open, close, open and close again is a massive compromise.

I would say if you want mirrorless buy a system solution, the workarounds are second best. The Leica digital is probably the worst of all the workarounds I’ve met. Use it as a rangefinder and use live view to verify lens calibration.

 

[Ko.Fe.]

I have all three. DSLR, RF and mirrorless.

SLR/RF systems are in use for decades now. RF is getting close to the century. SLR is more than half. DSLRs are still in use by many professional photogs.
User of DSLR and RF just have to make sure lens is aligned and pay attention to DOF for focus-recompose.

Here is no big focus accuracy issues with DSLR and RF in the real world. As long as user ain't dummy. I see W/O f1.1 and wider in focus pictures with RF. And I never had problem for get my AF 50L f1.2 in focus on DSLR. Never used LV on my DSLRs. Tens of thousands pictures, in focus and with use of tracking AF.

With DSLRs it doesn't matter how much camera costs, how old it is, consumer, semi or pro model. AF works nearly the same as long as it is quality lens. Just Sigma lenses needs to be avoid, they can't make AF DSLR lens without focus issues.

 

[pvdhaar]

For me, mirrorless is all about comfort: I can do all settings through with the EVF. No more squinting at tiny print that I would need reading glasses for.

 

[willie_901]

I don't think work arounds are worth the effort.

Lens AF motor technology, increased camera CPU speeds, on-sensor phase-sensitive AF detection and EVF improvements have combined to make mirrorless camera AF fast, flexible and efficient. This was not always the case.

With my X100T and X-Pro 2 I use the EVF/OVF system to implement AF manually. I use the back-button or shutter half press modes to focus and recompose. I use the audio beep, the finder green dot/focus box indicator or the electronic rangefinder, ERF (a small EVF display of the on-sensor focus-region with focus peaking) to confirm AF lock. For my needs this works remarkably well - even in low light. Once and a while I use the lens focus-by-wire barrel to make small changes.

Occasionally I use the EVF and other more sophisticated AF modes. These are nice to have at hand.

When I was doing interiors photography, I set a X-T1 with the 10-24/4 on a tripod and used articulated LCD live view to simulate a using a view camera. I used AF manually to spot focus an appropriate hyperfocal point for each composition. The infinity point would the end of the room (or a wall in the most distant room. I only needed a handful of DOFs and focus points for 95% of the compositions.


Devotion to M/LTM lenses lenses is not a work around. So, if I owned a collection of cherished M/LTM lenses, I would use a M typ 240, 262 or M10.

 

[Lee Rust]

My autofocus cameras are certainly easy to shoot with, but I find that I'm often fighting with them over their choice of focus point.

Focus peaking or zooming are nice for telephoto and precision work, but a rangefinder can do the job much faster with wide or normal lenses in most situations. With RF plus convenient live view or EVF, a camera like the M10 is the best of all possible worlds for me.

 

[RichC]

EVF cameras outclass optical viewfinder cameras in every way. I bought a Sony A7R II a couple of years ago to try (my first ever EVF camera), and I was blown away. I sold all my optical viewfinder cameras, and will never use those obsolete dinosaurs again! My reasons:

• What you see is exactly what you get (my main reason).

• Ability to use almost any lens.

• Small size and low weight (compared with SLRs).

• Ease of manual focus (often no need for focus peaking or magnifying with Sonys - edges between objects shimmer slightly when in focus, so similar to a microprism in film SLRs).

• Menus displayed in viewfinder (allows settings to be changed quickly without moving camera from eye).

• Viewfinder unaffected by bright sun, so menus and photos can be seen (unlike screens).

• No blurred photos from mirror shake (which all SLRs suffer from).

• Built-in image stabilisation (allows insanely low hand-held shutter speeds).

 

[jsrockit]

My autofocus cameras are certainly easy to shoot with, but I find that I'm often fighting with them over their choice of focus point.

Why can't you choose the point then?

 

[Dogman]

EVF cameras outclass optical viewfinder cameras in every way. I bought a Sony A7R II a couple of years ago to try (my first ever EVF camera), and I was blown away. I sold all my optical viewfinder cameras, and will never use those obsolete dinosaurs again! ....

I bought my first EVF camera when Panasonic introduced the G1 in 2008. Also tried the Olympus E-P2 with the accessory EVF. I've also owned and used the Fuji X-T1 and X-E2S and the Olympus OMD-E1. A few others belonging to other people along the way. I've really tried to find an EVF that I liked and it simply hasn't happened. In addition to my own vision limitations there's just this inorganic look about the subject, a loss of contact. It's like paying to attend a live music concert and then having to watch the performance on the big screen rather than watching the musicians directly. I can't explain it any better than that other than saying it's not comfortable for me to use.

 

[Dogman]

My autofocus cameras are certainly easy to shoot with, but I find that I'm often fighting with them over their choice of focus point
....

Perhaps you should use the focus and recompose method employing only the center AF sensor. It's how we used rangefinders and the center microprism screens of SLRs for decades.

 

[willie_901]

My autofocus cameras are certainly easy to shoot with, but I find that I'm often fighting with them over their choice of focus point.

Improving the focus-point choice success is achieved by optimizing AF parameters. Newer cameras typically have more option improve focus-point choice performance. Low light combined with low contrast focus objects remains a challenge.

Another approach is to use focus and recompose. Set the focus region to the center of the frame and use the smallest possible the focus-region area. Disable as much AF automation as possible. Achieve focus on the object of choice, lock focus and recompose. The challenge is to figure out how to use the camera's AF system to simulate using a RF camera. For some mirrorless cameras this may not be possible. Of course focus and recompose is not practical when DOF is thin or in other situations where critic focus is required. But this is true for analog, mechanical focus cameras as well.