SL2-S Video Autofocus

[ahendy]

Advertisement (gone after registration)

Just a quick observation here.. 

I was eagerly awaiting the new firmware for the SL2-S because of the improved video continuous AF. I've spent a lot of time with Canon and Sony (R, R5, R6, A7s III, etc) and was excited to see if the AF from the SL2-S could become even half as good as any of those..

Initially, when shooting at 24fps, I was quite disappointed. Detection (box around face/subjects) was quite good but AF was just painfully slow. Upon switching to 30fps things were a bit better. At 60fps it was incredibly good — almost EOS R level!

I've since read about this phenomenon with regards to the Panasonic S1, S1R, S1H, S5 cameras and am here to confirm that it applies to the SL2-S as well. If you want good continuous AF in video with an SL2-S, 60fps is your friend. If you need to shoot at 24fps... you're SOL. It's still just not very good.

That's all

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[hansvons]

Interesting find. Thanks.

[Slender]

It makes sense as the sensor output/readout is faster at 60fps, it gets interpreted faster by the DFD system. That's why its (very IMHO) good for stills, there is no restriction on how fast the sensor readout can be used for DFD calculations (I think I read somewhere it can make up to 600/700 depth-calculations per-second 🤭). The base EVF rate of 60fps for stills (up to 120fps) and the fact it gets even speedier (but lesser definition) when using AFC in picture mode is a good indication things behind the scene go relatively fast... So at a constrained and constant 24fps readout/recording for video performance degrades.

Shutter angle will also have a positive effect in theory. If you can live with the effect they produce on motion blur. APS-C v FF should also affect this as either pixel-mix or full-scan kicks-in on a smaller surface to scan.

In my experience I like how you can control the smoothness of aufofocus pulls in video mode (SL2 on current FW... more to come soon hopefully for us). When it works it looks very natural, almost handmade.

Edited June 9, 2021 by Slender

[markieh]

Thanks aheny, I'v been looking for "any tricks" that could improve video auto focus, 60 frames really helps. thanks for that. I also tend to use the TL lens's (the 11-23 is great)

in  APSC mode which also improves the focus speed and smoothness.

Mark

[TealWayFilms]

Agree with the TL/CL lenses for video on my SL2-S. I have the 18-56 (with a variable ND already added) in my bag when I travel. It's small, light and perfect for quick video when I'm mainly shooting stills with the SL 24-90 or 35 APO. Switch to the 18-56 lens and switch to video and I'm ready for a short handheld clip .

 

To address the original autofocus concerns, I don't use autofocus. I switch to manual focus and use the joystick to do back button manual focus when using the 18-56.

Edited November 20, 2023 by TealWayFilms