Sony A7S III

[Llaasseerr]

 

3 hours ago, cpc said:

The sun is so bright that you'd need significant underexposure to bring it down to below clip levels (on any camera). And these images don't look underexposed to me. A clipping value of 0.87106 is still very respectable: on the s-log3 curve, this is slightly more than 6 stops above middle gray. With "metadata ISO" cameras like the Alexa the clip point in Log-C moves up with ISOs higher than base, and lower with ISOs lower than base. But on Sony A7s cameras you can't rate lower than base in s-log (well, on the A7s you can't, at least), so this is likely shot at base s-log3 ISO 640.

I any case, the s-log3 curve has a nominal range of around 9 stops below mid gray (usable range obviously significantly lower), so this ties up with the boasted 15 stops of DR in video. You can think of the camera as shooting 10 - log2(1024/ (0.87*1024 - 95)) bit footage in s-log3. That is, as a 9.64 bit camera. 🙂

Right, a far as partially mapping to s-log3 this camera is gonna fill all the slots below middle grey because it's an excellent low light performer. Thus leaving a deficit of highlight capture because the sensor is going to clip before the expensive pro cameras. But it's just how much highlight capture that is in question. It would also be helpful to see a lens cap test to see where black levels are at with both s-log3 and ProRes RAW.

[Llaasseerr]

4 minutes ago, Hangs4Fun said:

I hope they haven't taken notes from Canon's Cripple hammer.  Would it be expected to get close to 38.42 in that published clip, what was the expectation?

Are you thinking that it is pre-release firmware issues and/or the footage itself?

 

Absolutely no way it would get anywhere near 38.42, that's Alexa territory. But I was expecting more than 12 considering the DR test that Gerald Undone did.

You make a good point that maybe this footage was shot slightly overexposed and got exposure adjusted down, or maybe he did something else wrong in post. So it's really too early to say.

[Hangs4Fun]

16bit RAW to SSD $/GB costs vs 10bit All-I internal to CFexpress Type A

I'm really looking forward to using the RAW output.  I know they are outputting in 16bit RAW over HDMI, and my Ninja V will get a firmware update that will allow me to capture that output as 12bit ProRes RAW HQ upto 4K/60p.  Though I am sure there will be a recorder coming out soon that will record the full 16bit RAW (maybe Ninja V2)  Just getting the proper SSD's for the Ninja V to handle this new RAW is costing more money, though I can't complain.

Besides not being able to capture internal RAW, the other main reason I am not considering getting CFexpress Type A cards is the $$ per GB costs with that compared to external SSD costs.  The difference is significant, over 13 times more expensive.  There is only 2 options that require the CFexpress Type A cards, with many options being supported by V60 and most of the ones I will be shooting in requiring V90.  Beyond V90, I will just use external RAW.

If you compare CFexpress Type A $/GB vs Atomos Supported SSD's rated to handle 12bit RAW ProRes HQ $/GB you get:

• $2.50 per GB for CFexpress Type A
• $0.19 to $0.25 per GB for Atomos approved SSD for RAW on Ninja V

I just used the Ninja V https://www.atomos.com/drives supported media page, and looked up the cost of 2TB and 480GB OWC Mercury Extreme Pro 6G drives and divided the latest prices by the gigs and compared that to the Sony TOUGH card prices ($399 for 160GB).  I'm probably going to have to wait 2 years or more for the CFexpress Type A prices to go waaaaay down before I would ever consider using them.  Plus you can't even do RAW to them, so my plan is to use V90 Sony G cards for main shots, Sony M V60 for longer run stuff, and special stuff RAW out to SSD.  Unless someone pays me extra to do all RAW.

But $0.19 versus $2.50 makes CFexpress Type A 13.16 times more expensive per GB (I've had my Ninja V since the end of 2018, so I'm not counting that cost).

[Llaasseerr]

3 hours ago, cpc said:

A clipping value of 0.87106 is still very respectable: on the s-log3 curve, this is slightly more than 6 stops above middle gray. With "metadata ISO" cameras like the Alexa the clip point in Log-C moves up with ISOs higher than base, and lower with ISOs lower than base. But on Sony A7s cameras you can't rate lower than base in s-log (well, on the A7s you can't, at least), so this is likely shot at base s-log3 ISO 640.

I any case, the s-log3 curve has a nominal range of around 9 stops below mid gray (usable range obviously significantly lower), so this ties up with the boasted 15 stops of DR in video. You can think of the camera as shooting 10 - log2(1024/ (0.87*1024 - 95)) bit footage in s-log3. That is, as a 9.64 bit camera. 🙂

Yeah but the amount of DR doesn't shift much at all with Alexas when you for example use an ACES IDT rated for a different ISO. 

As I mentioned, when linearised 0.87106 works out about half a stop more than the a7s. It's okay, but it seems less than the sensor is capable of.

I just checked Gerald Undone's DR test again, and it's clipping at around the same point - around 0.87106. It looks like it's at about 880/1023 on his chart. So that would appear to be the max value.

 

[Hangs4Fun]

13 minutes ago, Llaasseerr said:

Absolutely no way it would get anywhere near 38.42, that's Alexa territory. But I was expecting more than 12 considering the DR test that Gerald Undone did.

You make a good point that maybe this footage was shot slightly overexposed and got exposure adjusted down, or maybe he did something else wrong in post. So it's really too early to say.

yeah, I for one will be publishing a ton of test footage when my A7SIII comes in.  I'm hoping Atomos gets their firmware released in time.  But even if it doesn't the new All Intra should be decent to look at.  The real test will be when there is a 16bit recorder that we can see footage from, since that will be the full potential of this camera.

my guess is that the footage has some overexposure in it.  S-Log3 can be tricky in mirrorless to expose properly, there is none of the cool tools you have in the pro Sony cameras.  If they didn't find 32% gray properly and bump up 2 stops from there, then the results we see are what I would expect.  Since most people (rightfully so) shied away from using S-Log3 in 8bit mirrorless camera's they are rusty on how to properly expose it. 

I will bet you lunch that they got zero at middle gray and then added 2 stops from there (instead of starting at 32%).  Phillip Bloom has some downloadable footage from his time with the A7SIII on his Vimeo channel.  Haven't had time to see what he put there.  He did have the Atomos RAW option (though pre-release).

[Llaasseerr]

Just now, Hangs4Fun said:

yeah, I for one will be publishing a ton of test footage when my A7SIII comes in.  I'm hoping Atomos gets their firmware released in time.  But even if it doesn't the new All Intra should be decent to look at.  The real test will be when there is a 16bit recorder that we can see footage from, since that will be the full potential of this camera.

my guess is that the footage has some overexposure in it.  S-Log3 can be tricky in mirrorless to expose properly, there is none of the cool tools you have in the pro Sony cameras.  If they didn't find 32% gray properly and bump up 2 stops from there, then the results we see are what I would expect.  Since most people (rightfully so) shied away from using S-Log3 in 8bit mirrorless camera's they are rusty on how to properly expose it. 

I will bet you lunch that they got zero at middle gray and then added 2 stops from there (instead of starting at 32%).  Phillip Bloom has some downloadable footage from his time with the A7SIII on his Vimeo channel.  Haven't had time to see what he put there.  He did have the Atomos RAW option (though pre-release).

The easiest way to visually expose it is not in log. just treat it like a film camera and use a light meter. Or if you want to use a monitor, add a LUT that makes it Rec709 and expose for the middle grey value (around .45). In fact, the narrow green band with false color tools generally falls on the Rec709 middle grey -but obviously check that beforehand. A decent grey card is your friend.

I'll check out Bloom's download on Vimeo.

[Llaasseerr]

Actually, I just checked and Slog3 and Rec709 both have almost the same middle grey value of around 0.41 - which I imagine Sony did by design.

[Hangs4Fun]

1 minute ago, Llaasseerr said:

The easiest way to visually expose it is not in log. just treat it like a film camera and use a light meter. Or if you want to use a monitor, add a LUT that makes it Rec709 and expose for the middle grey value (around .45). In fact, the narrow green band with false color tools generally falls on the Rec709 middle grey -but obviously check that beforehand. A decent grey card is your friend.

I'll check out Bloom's download on Vimeo.

I hear you, I just rarely carry a light meter into wilderness, lol.  BUT... that being said, I do ALWAYS have a grey card with me.  Only problem is, I no longer carry a monitor/recorder.  For about 2 years I was bringing a SmallHD with me (and the batteries, ugg).  when you already have a heavy enough backpack for your 1 to 2 week stay in wilderness, and then add photography gear for landscapes/astro/wildlife, and then add more weight and volume for filming gear (drone, video, audio), you wish you had a Sherpa.  So now when I do my solo wilderness trips, I have to get creative on exposure.  For studio work and on location filming for video production work, it's a whole other ball game.  Yeah then I could definitely use my 478 and meter properly and color checker charts.

When I saw that outdoor footage, I immediately thought of my backpacking adventures and the limitations it puts on me.  But yeah, you are probably right, most of the time when you see footage outdoors, they probably didn't have to hike several days to get there, and easily could have the right gear to set exposure.  For me, I have my little 18% grey card and I have to get very creative to use it in the field. 

If you have any suggestions for a super light weight method for setting proper exposure for what I described above, I would greatly appreciate it.  I don't plan on using my Ninja V in those conditions, so will have to rely on what the camera has built in (and they sadly still have not provided us with scopes or false colors).  One VERY promising thing though, is that it is rumored that the Sony Xperia Mark II PRO (the PRO specs haven't been officially released yet).  But I have heard it might have hdmi, which means I could use it as my monitor to get false colors and scopes potentially...

[Llaasseerr]

Yeah that's a fair point about not carrying the light meter in the wilderness. The grey card is great to have in your pre-roll though. For me personally I found false color a great quick way of doing it. For on-the fly shooting I use a vari ND and a grey card and wait til I get green hitting the card on the false color then I'm good to go.

I hate frankenrigs too, but maybe look at getting a cheap small 5" lightweight plastic hdmi monitor with false color and custom LUTs like the Fotga. Just an aside, from what I gather the Pana S1H has a tool for exposing based on looking at a grey card - that sure would be nice in other small mirrorless cameras.

[Llaasseerr]

35 minutes ago, Llaasseerr said:

Yeah but the amount of DR doesn't shift much at all with Alexas when you for example use an ACES IDT rated for a different ISO. 

As I mentioned, when linearised 0.87106 works out about half a stop more than the a7s. It's okay, but it seems less than the sensor is capable of.

I just checked Gerald Undone's DR test again, and it's clipping at around the same point - around 0.87106. It looks like it's at about 880/1023 on his chart. So that would appear to be the max value.

 

Just following up on this again.

If I check the black levels of the Xyla on the vectorscope here, they correspond with the min black level in the s-log3 spec - around 96. So yeah, it appears the default Data levels interpretation is correct and I was wrong that it may be Video levels. 

 

[Hangs4Fun]

2 minutes ago, Llaasseerr said:

Yeah that's a fair point about not carrying the light meter in the wilderness. The grey card is great to have in your pre-roll though. For me personally I found false color a great quick way of doing it. For on-the fly shooting I use a vari ND and a grey card and wait til I get green hitting the card on the false color then I'm good to go.

I hate frankenrigs too, but maybe look at getting a cheap small 5" lightweight plastic hdmi monitor with false color and custom LUTs like the Fotga. Just an aside, from what I gather the Pana S1H has a tool for exposing based on looking at a grey card - that sure would be nice in other small mirrorless cameras.

yeah, I really love using my Ninja V and false color's, makes it fast.  I do use a variable ND (the PolarPro PM edition on my Sony 24GM f/1.4).  I really like your idea of using a cheap and light plastic monitor to get false colors.  But since I mentioned it, maybe I should upgrade my phone to the Sony XPeria 1 Mark II PRO if it actually does have an hdmi port.  Sony is interested in providing us monitoring capabilities with their top Xperia phones, I just thought it wouldn't be available until the Mark III.  The video tools on the non-pro Xperia 1 Mark II already have false colors and scopes, so if the PRO version adds hdmi,

I think that would be the best way for me.  Since I have to have a smart phone for my wilderness trips any way (not for cell service, but for using topo maps, and Earthmate bluetoothed to my InReach Explorer, controlling my drone, and backing up my footage at night in the hammock to a Samsung T5).  

[BTM_Pix]

14 minutes ago, Hangs4Fun said:

If you have any suggestions for a super light weight method for setting proper exposure for what I described above, I would greatly appreciate it.  

You might want to have a look at the Expodisc.

Pops onto your lens to get 18% grey for white balance but you can then also use it as an incident light meter too.

They have videos on their YouTube channel showing how to use it for WB and ones like this about using it to meter

 

[Hangs4Fun]

6 minutes ago, BTM_Pix said:

You might want to have a look at the Expodisc.

Pops onto your lens to get 18% grey for white balance but you can then also use it as an incident light meter too.

They have videos on their YouTube channel showing how to use it for WB and ones like this about using it to meter

 

Interesting, thank you.  For studio and onsite work, I would still use my 478 and my Color Checker video card...  But when doing more run and gun (shoot and scoot) in wilderness, this might be the perfect tool for me.  I watched the first video and will watch the others.

I'm really excited to finally have 10bit on my adventures and even better dynamic range.  But I'm very rusty on exposing S-Log3, since it is unusable on 8bit.  I like how quick I could set WB and Exposure though.  The 18% gray is awesome to set WB, but without false color I have to get creative on using it to set exposure.  If I'm being honest, I could use help properly exposing S-Log3 on the A7SIII when in wilderness without false color.  If this ExpoDisc worked in that case, it would be worth it to me to have something like this over a cheap monitor that may not work well in humidity, plus the battery weight and cables.

[cpc]

2 hours ago, Hangs4Fun said:

my guess is that the footage has some overexposure in it.  S-Log3 can be tricky in mirrorless to expose properly, there is none of the cool tools you have in the pro Sony cameras.  If they didn't find 32% gray properly and bump up 2 stops from there, then the results we see are what I would expect.  Since most people (rightfully so) shied away from using S-Log3 in 8bit mirrorless camera's they are rusty on how to properly expose it. 

I will bet you lunch that they got zero at middle gray and then added 2 stops from there (instead of starting at 32%).

For determining the clip point it doesn't matter if the footage is overexposed; overexposure doesn't move the clip point; if anything, it helps to find this point easier. All you need is locating a hard clipping area (like the sun).

 

re: exposing

While a digital spotmeter would be the perfect tool for exposing log, the A7s II does have "gamma assist" where you are recording s-log, but previewing an image properly tone mapped for display. The A7s III likely has this too.

You don't really need perfect white balance in-camera when shooting a fully reversible curve like s-log3. This can be white balanced in post in a mathematically correct way, similarly to how you balance raw in post. You only need to have in-camera WB in the ballpark to maximize utilization of available tonal precision.

 

[Llaasseerr]

8 hours ago, cpc said:

I any case, the s-log3 curve has a nominal range of around 9 stops below mid gray (usable range obviously significantly lower), so this ties up with the boasted 15 stops of DR in video. You can think of the camera as shooting 10 - log2(1024/ (0.87*1024 - 95)) bit footage in s-log3. That is, as a 9.64 bit camera. 🙂

Going back to this comment. So I'm someone that wants my DR above middle grey and in this case I would be inclined to just shoot with a -2 ND and push it 2 stops in post. I don't like grainless images anyway.  Looking forward to being able to test that theory out though haha.

[MeanRevert]

7 hours ago, Llaasseerr said:

Yeah that's a fair point about not carrying the light meter in the wilderness. The grey card is great to have in your pre-roll though. For me personally I found false color a great quick way of doing it. For on-the fly shooting I use a vari ND and a grey card and wait til I get green hitting the card on the false color then I'm good to go.

I hate frankenrigs too, but maybe look at getting a cheap small 5" lightweight plastic hdmi monitor with false color and custom LUTs like the Fotga. Just an aside, from what I gather the Pana S1H has a tool for exposing based on looking at a grey card - that sure would be nice in other small mirrorless cameras.

I use the same exposure method - green card and false color.  It's a shame that Sony doesn't have it built in like BM.

[Hangs4Fun]

26 minutes ago, MeanRevert said:

I use the same exposure method - green card and false color.  It's a shame that Sony doesn't have it built in like BM.

same, I will be using my Ninja V a good bit of the time.  I am looking for a better way to set exposure when I'm on a backpacking trip and not carrying the Ninja V.  18% grey card and custom zebra's set to 41% is what I have been doing.  Was curious if that would change with with the A7SIII since I would finally be able to use S-Log3.

The other option I mentioned was upgrading my cell phone to the rumored PRO version of the new Sony Xperia 1 Mark II which supposedly has hdmi and scopes/false color.  If that is the case, then I'm golden.

[cpc]

7 hours ago, Llaasseerr said:

Going back to this comment. So I'm someone that wants my DR above middle grey and in this case I would be inclined to just shoot with a -2 ND and push it 2 stops in post. I don't like grainless images anyway.  Looking forward to being able to test that theory out though haha.

This is too optimistic, I think. The A7s needed overexposure in s-log, it was barely usable at nominal ISO (and I am being generous with my wording here). With the lower base ISO in s-log3 of the A7s III (640 vs 1600 on the A7s), Sony now basically make this overexposure implicit.

[kye]

Brandon Li with a short film shot on A7s3, plus his impressions and some zoomed in examples of noise, IQ, and AF tracking etc.  Quite a useful video it seems:

 

[Daai]

not a7s3 question. But on a7iii would you get more DR on slog3 compare to slog2? i know 8 bit etc. but to get most dynamic range which profile?