Sony Fs700 Vs A7s

I would expect the APS-C crop to fix the aliasing of the A7S at the 60p framerate. Does it?

Demistate said:
Ailasing At different framerates:

I took the A7s and the FS700 and recorded them at various framerates to check for ailasing in the Slog 2 profile. Sony has been notorious for having "Highlight ailasing" when a really bright spot hits next to a very dark spot.

Take a look at the video:


My conclusions:

24P, look very good on both cameras, Highlight aliasing apparent on both, but the A7s has a small edge over the Fs700 on the downsampling from the 4K sensor.

30P, same as 24P on both cameras.

60P: A7s goes into a mode that looks worse than the 240P 2k pixel binning that the FS700 does. It's still very usable. FS700 stays the same quality as the 24P mode

120P (720P resolution): A7s only -- Is a zoomed in version of the 60P so the aliasing is even more pronounced. I'm not sure if this is APS-C crop, but it is NOT full frame.

240P: Fs700 Only -- Is still really good, but the noise is even more apparent as the internal electronics are not denoising the signal.


I've uploaded all the Raw clips on my site. I welcome your second opinion.
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Here is the first video I've professionally shot with the Sony FS700 and A7s:


Some notes of things I noticed:
  • White balance modes do not match between the two cameras. A7s has a lot more green in it.
  • Using LUT packages like ImpulZ and FilmConvert did not do a good job matching the cameras color wise. I still needed to create secondaries in Resolve and tweak things like the skin and everything else.
  • I used the FS700 as the CU with a Canon 70-200 2.8 IS, The A7s was on a canon 16-35 f/2.8.
  • The A7s will ALWAYS stop at 30 minutes recording time. I had to slate the interview multiple times while the FS700 could just roll untill I ran out of space.
  • The 50Mbps codec wasn't any cleaner than the internal AVCHD of the FS700 in controlled camera movements. I'm sure in more violent handheld, or scenes with a lot of movement (like water, or snow) would hold up better on the A7s.
  • I used variable ND on the A7s, it could be part of the massive color shift I was seeing.
  • Tonality of Slog2 matched perfectly on both cameras. It's just getting those colors to match took some extra time.
  • I used the A7s on a small glidecam rig for smooth shots, it worked out wonderfully since I was the only person doing any of the production. Saved my arms since it was so light.
  • It's not easy to switch framerates on the A7s. I really hope sony makes an S&Q button you can map to one of the buttons.
  • Being able to steal raw stills on the camera was nice and I could keep it on my body at all times when shooting with FS700.
  • The Sony 24-70 F/4.0 lens is so nice. I used auto focus on the Glidecam and it worked wonderfully
 
What PP settings have you used on both cameras? Well done match. How did you expose slog? 2 stops over?
 
jurny said:
What PP settings have you used on both cameras? Well done match. How did you expose slog? 2 stops over?
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I used Slog 2 on the internal AVCHD/XAVC on both cameras. I exposed about +1 to +2 stops over depending on the scene, and I denoised all footage before bringing taking it to Resolve, as Vision-Color recommends.

Normally I would add a film grain on top to give it all a consistent texture, but it gets completely lost in YouTube's compression so I just straight output it from there.

I did a UHD upscale of 1080P material since Youtube gives it better bitrate and the UHD versions look better than 1080P even when being played back on 1080P devices due to increased bitrate alone.
 
Does that mean that you took the longer route by using the stock PP7 with s-gamut and corrected tho colours by hand instead of using the sgamut==>rgb in resolve or any other color space in camera?
 
I leaned heavily on Film emulation Luts from ImpulZ and Film Convert. Of course there was still manual correction needed to get both cameras to match color wise.

With Slog2 there is never an easy route.
 
Samuel H said:
Thanks for the detailed report

* To set 1/45s, you have to tell the a7s to use half-stop-increments instead of third-of-a-stop-increments
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Where can I find that option? I've searched through all the menus but couldn't find it...

Edit: never mind, just found it. I just need to change the Exp comp.
 
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colour matching the fs and the a7s

colour matching the fs and the a7s

jurny said:
2 postts and you still havent replied to my question. i give up :D
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I am surprised this hasn't been discussed/tested in more detail as I suspect these cameras are used a lot together by a lot of people!
timmytimetravel and I have had 'some' success matching colour of the two by using the ITU709 matrix on the a7s and dropping the saturation a little, still needs more detailed testing though...
 
So, I only noticed today that the FS7 does 4K/60P, wow! Any FS7 users can chime in about their experiences vs the A7s? Is the SLog2 implementations the same between the cameras?
 
SuperSet said:
So, I only noticed today that the FS7 does 4K/60P, wow! Any FS7 users can chime in about their experiences vs the A7s? Is the SLog2 implementations the same between the cameras?
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I think the general consensus on the FS7 is that it is next level in every way compared to any DSLR including A7S except when it comes to the menu system and low light ability (but its not shabby in that department by any means)

FS7 has Slog 3 and 10bit codec as well = way better.
 
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