A7s sample footage

paulcurtis said:
I'm not so convinced with Slog2 at the moment on this camera, i did some transmission wedge tests, very quick and dirty (i will do them again properly though).

There's perhaps a 2 stop advantage in Slog2 (maybe 12 overall). But the distribution of those stops in Slog is fairly flat, which is what you want in high range situations. But the black level is higher than it is on the FS700 - it's riding around 25/30 code values for me (unless i'm doing something wrong). This means that your useable range is 25 to 255, split into 11/12 stops, so 20ish code values per stop. Whereas with cine4, yes the blacks roll off quicker and the highlights have a knee but the blacks in Slog are *very* noisy, so first stop unusable IMHO, lots of purple(!) blobs. So you're going to crush those blacks anyway. Then, depending on subject, the last few stops might just be specular.

So with cine4's 10ish stops divided into 0-255 the distribution for skin/interiors may have more tonal details, plus you can mix and match colour spaces.

I'm not saying there are any problems with Slog2 but it's not a be all and end all, IMHO at this early stage, it's implementation is worse than it is on the FS700. If only Sony did 10bit, then it probably would be the ideal way to shoot. Why... why.... why....

cheers
Paul
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Hey Paul,

So I'm working on this right now before lunch (SOOO HUNGRY been doing this since like 7Am this morning and forgot to eat haha) and I've come across what I consider a far worse issue with anything outside of Slog2... banding. The banding in Cine Profiles in lower mids can be quite atrocious. Cine2 and 3 seem to handle this a little better than 4, but 3 clips sooner than 4 up top.

I do feel that the banding's a lot more troublesome here, but also it's not unmanageable. Exposing more for shadows with the current Cine/Pro PicPro I'm working on looks pretty okay. I don't know if I like it as much as Slog2 but the results are cleaner. I should probably go and find a food truck.. and grab some footage with the new settings.
 
Kholi said:
Hey Paul,

So I'm working on this right now before lunch (SOOO HUNGRY been doing this since like 7Am this morning and forgot to eat haha) and I've come across what I consider a far worse issue with anything outside of Slog2... banding. The banding in Cine Profiles in lower mids can be quite atrocious. Cine2 and 3 seem to handle this a little better than 4, but 3 clips sooner than 4 up top.

I do feel that the banding's a lot more troublesome here, but also it's not unmanageable. Exposing more for shadows with the current Cine/Pro PicPro I'm working on looks pretty okay. I don't know if I like it as much as Slog2 but the results are cleaner. I should probably go and find a food truck.. and grab some footage with the new settings.
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Do you mean banding in the source material? This doesn't sound right. Can you post samples?
 
cpc said:
Do you mean banding in the source material? This doesn't sound right. Can you post samples?
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Hey cpc,

I'll post an example soon, just packed everything up and need to finally eat, and start on my tower rebuild >.< Need to reseat CPU .... and eat.

I hope I'm doing something wrong, I'm just seeing a lot of crazy banding down bottom and it's fine if you just ramp up until it goes away, it's also mostly in very low lit comps or extreme contrast situations.

Paul might be able to do a better job of checking it out, again I'm totally fine with having done something wrong! Really digging the camera (outside of APS-C mode and high speed stuff) and want to help figure it out.
 
ssvet said:
Correct. When shooting in S-Log the lowest ISO setting is 3,200.
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Thanks, ssvet.

Now trying to figure out in my head how Kholi can shoot SLog2 on a bright day with only a ProND64 (6 stop), while Erik required to stack ProND500 (9 stop) + ProND200 (7 2/3 stop). No shutter compensation for Kholi, and surely not shooting cpc's Sunny 16™? Erik's stacked ND requirement makes more sense to me at ISO 3200, save ETTR more and swap out the ProND200 for, say, a 64 or 32, reducing 2 or 3 stops of ND. That's still 14 stops or more of ND versus 6 stops. Thinking...
 
Samuel H said:
I just commented in that video: "I think the extra sharpness you see is actually false detail, a byproduct of aliasing, created by a bad downscaling algorithm."
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i'd have to agree with this assessment from the Vimeo clip as well. Would be nice to see a source.
 
Now trying to figure out in my head how Kholi can shoot SLog2 on a bright day with only a ProND64 (6 stop), while Erik required to stack ProND500 (9 stop) + ProND200 (7 2/3 stop). No shutter compensation for Kholi, and surely not shooting cpc's Sunny 16™? Erik's stacked ND requirement makes more sense to me at ISO 3200, save ETTR more and swap out the ProND200 for, say, a 64 or 32, reducing 2 or 3 stops of ND. That's still 14 stops or more of ND versus 6 stops. Thinking...
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Erik had mentioned he didn't ETTR and Kholi does. Heck, just crank the shutter and shoot like you just got hired to do a Nike ad. Saving Private Basketball shoes.
 
Christopher Barry said:
Thanks, ssvet.

Now trying to figure out in my head how Kholi can shoot SLog2 on a bright day with only a ProND64 (6 stop), while Erik required to stack ProND500 (9 stop) + ProND200 (7 2/3 stop). No shutter compensation for Kholi, and surely not shooting cpc's Sunny 16™? Erik's stacked ND requirement makes more sense to me at ISO 3200, save ETTR more and swap out the ProND200 for, say, a 64 or 32, reducing 2 or 3 stops of ND. That's still 14 stops or more of ND versus 6 stops. Thinking...
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On a sunny day, 9 stops will get you to f/5.6 at a 1/50th.
 
Complete overcast day where I am located in Australia this morning. For convenience, grabbed the GH2 in photo mode, ISO 3200, standard profile, AWB and/or WB set to 5600K, Tak 50mm set at f3.5, ProND1000 10-stop, internal light meter mode set to (.), showing +1 stop to +2 stops pointing into brightest part of dull clouds. No specular highlights to be found at the moment, the ocean is dull and flat. Further review later today or tomorrow, when the sun returns.
 
L1N3ARX said:
A few shots with the Tokina 28-70
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Thanks for posting, Roman. Good samples of daytime shots in the sun and indirect day light. I am starting to question if the Sony a7S firmware needs a tweak for S-Log2, or if the 8 420 50Mbps codec is not enough to handle post processing, or the sensor is simply hyper sensitive or other theory? I mentioned that I was observing a lean towards magenta in some of Erik's Sunset Cliffs shots. Observing a few of Roman's shots in the alley, does not appear to be direct sunlight, nor is the camera lens pointing towards the sun in the extracts, below. paulcurtis said two pages back, "lots of purple(!) blobs". Perhaps what paul is referring to relates to samples below.

a7S_S-Log2_Magenta_Mauve.jpg

Top sample, the shadow and the mortar are not grey. Middle, hair showing magenta tones. Jeans similarly have magenta/purple tones, although could be part of the synthetic material.

Mentioned as reference to what I think I am seeing, not intended as a blight on Roman or Erik's excellent work. I am trying to determine if I am properly calibrated or if the a7S SLog-2 has a problem/limitation or requires a different shooting and/or post process. Thanks.
 
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That's what Paul's referring to for sure. I've seen a lot of it in my footage, just trying to ignore it overall haha.

Even with the other gammas, I'm finding it hard to strike a balance between shadows and highlights, but of course there're still a lot of settings to explore.
 
Thanks for the confirmation and the Profile work over the last couple of days (and nights), Kholi. Now I think I am reasonably calibrated. Solution to a7S S-Log2 'purple greys', we'll see in due course.
 
I was shooting my kids riding their bikes at the 'proving grounds' with the 5D raw on the weekend and I'm seeing the magenta shift as they ride out of the shadows into the sun. I'm going to get a Hoya UV & IR filter to see how it affects the 5D and the A7s. I'll be shooting at the proving grounds again with the A7s with the same lens (Pentax 35-105 'stack of primes'). Very interested to see how S-Log performs next to raw.
 
I had a lot of moire in the ocean when I was shooting in 120fps. Purple color like crazy. Not so much in 24p. I did grade the image to get a look I liked. That doesn't mean it's for everyone. :-D

Looking forward to using Kohli's profile. I like the idea of boosting the saturation and keeping Slog2 for better dynamic range. If I can keep the noise in check than thats a win. ISO 3200 is a b*@th!

I also was using traditional methods of shooting in log and need to try the 2 stops over method. However the cameras meters are less than perfect to get you in the perfect zone. I think it's going to have to become a feel more than a technical thing. Do you know what I mean?
 
Erik Naso said:
I had a lot of moire in the ocean when I was shooting in 120fps. Purple color like crazy. Not so much in 24p. I did grade the image to get a look I liked. That doesn't mean it's for everyone. :-D

Looking forward to using Kohli's profile. I like the idea of boosting the saturation and keeping Slog2 for better dynamic range. If I can keep the noise in check than thats a win. ISO 3200 is a b*@th!

I also was using traditional methods of shooting in log and need to try the 2 stops over method. However the cameras meters are less than perfect to get you in the perfect zone. I think it's going to have to become a feel more than a technical thing. Do you know what I mean?
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Just use Cine 2 to even 1 then over S-log. Personally, I see that s-log is straining the codec. Outside in bright bright conditions with tons of ND S-log looks decent. But I also find that Cine 1 or 2 can get you right there with a bit of CC.
 
I think SLOG performs fantastic but if you go crazy with the grade, you'll break it. Pair with Filmconvert or Impulz and aim for a flatter filmic grade and you'll be fine. Works great for Terrance Malick but perhaps not as well for Michael Bay, basically.
 
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