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Sony A7s, FHD camera, with 12Mp sensor, big DR
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  • Cine1 gamma has proven much easier to use than S-Log2 on the a7S, while delivering the exact same exposure latitude.

    • You can judge exposure for Cine1 from the monitor.

    • A proper exposure for Cine1 is +0.0.

    • Cine1 is available down to ISO 100, compared to ISO 3200 for S-Log2, which gives 3.5 more stops of highlight range, reducing the need for a neutral density filter.

    • Cine1 has better precision.

    Cine1, a.k.a. HyperGamma 4 or HG4609G33, is designed to be similar to Rec.709, making previewing and grading easier. It has 460% the white highlight range of Rec.709. Cine1 has whites going to 109% RGB, and saturated colors to 113.6%. There's 0.8 stops of highlight range from 100% to 109%, and another stop up to 113.6%. The a7S is actually using the entire range of the Cine1 curve up to 113.6%, giving a huge range of saturated highlights. I built an ACES IDT for Cine1.

    Cine2 (HyperGamma 2, or HG4600G30) is the same as Cine1 except it scales the signal to put the white clipping point at 100% instead of 109%. Cine2 might be useful in situations where you want zebras to show you the recorded white clipping point, or if your post workflow doesn't let you access values above 100%.

    A color mode setting of 'Still' is giving me the most accurate color. There's something wrong with S-Gamut on this camera. It doesn't correspond to any of the S-Gamut decoding matrices that Sony has provided. The other color modes are all undersaturated or oversaturated.

  • Thanks a lot for this detailed explanation, Balazer!

    Could you write a word or two about Cine 3 and 4 as well ? I found Cine 4 quite useful in darker situations.

    And you are perfectly right about S-Gamut in the A7S, it's really whacky and much harder to grade than footage from a FS7.

    And would you consider posting that IDT for the community?

  • Thank you, @nomad. :) I don't know anything about Cine3 and Cine4. It seems Sony has not provided the specifications of those gamma curves. I think they are variations on the same general idea as Cine1 (similar to Rec.709 but with an extended highlight range), though without a specification they are of no use to me. I wonder if it's possible to transfer Cine3 and Cine4 from a camera using CvpFileEditor.

    The Cine1 ACES IDT is posted here: http://www.jbalazer.com/aces-in-sony-vegas It's an OpenColorIO config for Sony Vegas Pro, with an spi1d LUT for the Cine1 curve. I assume Rec.709 primary chromaticities. You should be able to transform the LUT into whatever LUT format you need. I got the original LUT specification from CvpFileEditor. I can tell you how to export from that, if you want to go to the source.

  • @balazar what is the estimated dynamic range of Cine1 vs S-log?

  • If you mean highlight range, e.g. stops above middle grey, Cine1 has a range of 460%, compared to 1300% for S-Log2 (relative to Rec.709 at 100%). So S-Log2 has 1.5 stops more highlight range.

    But the usable dynamic range is practically the same for both, being limited by noise and color shifts in the shadows. The amount of noise N stops below the white clipping level is the same for S-Log2 and Cine1 on the a7S. S-Log2 extends more stops below clipping, but the lower part of the S-Log2 output on the a7S is too noisy to use. And that's why you need to overexpose by 2-3 stops in S-Log2 on the a7S.

    These two videos illustrate how the dynamic range and exposure latitude compare:

  • @balazar thanks for the info i will look around for some best settings - i find it so difficult to really make the colors punchy in slog. Also i hear a lot about aces but cant seem to find a lot of info on what it is and how it is useful, can you give direction?

  • If you check Balazar's link and scroll down, you'll find some recommended reading…

  • If you are trying to manipulate S-Log2 levels directly to produce standard video output, you are going to have a very hard time. S-Log2 was never meant for that. S-Log2 has no highlight roll-off and it's not very similar to Rec.709. S-Log and S-Log2 were always meant to have some transformation into another color space for grading, like Cineon or ACES. S-Gamut also needs some transformation: it needs to be linearized and then put through a decoding matrix. (or do all of that with a 3D LUT) If you're not decoding S-Gamut with a matrix, it will produce hopelessly weird colors that you can't correct with any standard color tools. Even with Sony's decoding matrix, S-Gamut from the a7S has a lot of color inaccuracies that you don't get with S-Gamut on a CineAlta camera, so I no longer recommend S-Gamut on the a7S.

    If you want to manipulate levels directly with standard tools like levels and curves, I recommend shooting in Cine1 (or Cine2-4) with 'Still' color. It has a nice highlight roll-off, and you'll get pretty close to what you want just using a levels filter to select a range of the Cine1 RGB levels and stretch that out to Rec.709. More complicated things can be done with curves.

    But of course I recommend ACES or ACEScc because they take care of the transformations for you, for whichever color space you shoot in. My video tutorial covers the basics in Sony Vegas Pro. Nuke does ACES too. Resolve has an ACES workflow also, but I haven't spent much time trying to figure out Resolve, and I don't know if the ACES implementation in Resolve is really correct or useable.

  • Have you had any problems using A7s and follow focus? I just bought Shoot35 r3 follow focus unit along with Fotga DP500 rails and whenever I try to focus lenses, the camera leans either upwards or downwards. It seems that the Fotga plate doesn't hold tight enough to keep the camera steady. Using other plates has the same problem as well. I'm using Contax Zeiss lenses with CY-E-mount adapters. Any ideas how to stabilize and nail the camera in it's place while focusing?

  • @vstardust:

    You can use multiple tools to stabilize this movement. But the best way is, to use a cage for your camera, which is also mounted on top of it (so the camera body is really "jammed" inside and cannot move any more). The cage you can then mount MUCH tighter - Or even with multiple screws - onto the QR plate (or baseplate). That way you´re minimizing the movement with EVERY lens you´ll ever mount to the body.

    On the other hand you can also use a lens stabilizer (like the lanparte TS-02 or similar ones) - Especially with bigger lenses it´s a good way. Though: With compact lenses (like the C/Y) that´s not possible (as there´s not enough space to use it). Also it´s not helping THAT much to be honest. You could also use a speedbooster for your C/Y lenses. As there you also get a tripod support which you can then combine with a spacer for your camera body (to get also multiple screw down points - One on the adapter and one on the body). But that´s more "DIY like" as you need to find or build a compatible spacer (and this solution is not very handy if you want to change the C/Y lenses to native Sony-E ones - As you cannot remove the adapter anymore that easily).

    Btw.: According the C/Y lenses also a CLA process is helping ALOT (CLA = "cleaning lubricating adjusting"). The most C/Y lenses are quite "stiff" (focus ring wise). And a very light grease is reducing the camera and image movement while focusing significantly. Though keep in mind: These are stills lenses. They always have a little bit of "play" in the focusing mechanism / helix. So the max. stability is always limited ^^.

    Additionally you can also try to "limit" the max. focusing way of your lens. For example: Use a hard stops follow focus, and don´t use the hard stops for your focus pulls - Use them to set the closest and infinity focus. Most lenses are turning OVER the infinity point (without finde adjustment). So there you could set the point with the 1st hard stop. The 2nd one you set a little bit BEFORE the lens limiter is hitting. That way you ALWAYS get the limit from the follow focus and not from the lens. And with this method the force isn´t applied to the lens (aka the body - aka the image) - It´s applied to the hard stops (and so the follow focus only) ^^.

    Ok. That´s it. Sorry for the long text (@ all).
    But these are the options you have to minimize the frame movement ^^.

    LG

  • Wow... thanks a lot @Tscheckoff, you really seem to know your game. I thought about getting a cage, but I didn't realise that they can be tightened also from the top as well to minimize movement. I think that's the best way to get this problem sorted.

    I'm not looking for really high end cage since I don't use external monitors with my set (atleast yet) because I want to keep everything really portable. Therefore this seems to be very cost efficient and small in size choice: http://amzn.to/1I36HnF

    Do you have any experience, would this kind of hotshoe based tightening system be the best choice strenght/cost wise?

    Thanks in advance. :)

  • @vstardust:

    Yes. Locking down from top is helping alot. The SmallRig cage you linked to should be enough yes (they offer good quality). At least it´s locking down from top AND it´s not THAT bulky compared to other solutions. (Btw.: You could even go for the cable lock at the side - For the HDMI cable for example.)

    About locking it down on the baseplate / QR plate: There are two 1/4" slots at the bottom. They are quite tight together. But if you use smaller head screws (from a local hardware store), it´s maybe possible to use both threads (to get a tighter and 100% non sideway twisting connection). Btw.: Locking down from top is only possible with the hotshoe of the camera - As there are no other connections possible. ^^

    LG

  • For anyone using Adobe Lightroom or Adobe Camera Raw to process the a7S's ARW files:

    You get much more accurate color by changing the camera calibration profile to Camera Standard. Adobe Standard gives weird colors that you can't fully correct within Lightroom. Camera Standard an almost perfect match for Sony Image Data Converter. I can't believe I had this camera for a year before I figured this out.

  • @Blazer are you referring to the sRGB option for color space?

  • @nosignal, I'm not sure if you're referring to my post about video color spaces, or raw images in Lightroom. Either way, the color space setting in the camera makes no difference. Please let me know what you mean, and I can try to answer better.

  • @balazer I was referring to the lightroom post where you said calibrate the color profile to standard instead of adobe.

    Did you mean do the calibration within adobe lightroom? Now that I'm reading it back, it seems like that is what you meant.

  • Yes, I meant in Lightroom's develop module, you go to Camera Calibration and change the profile to Camera Standard.

  • Sony Alpha A7S Mirrorless Digital SLR Camera Body + 1 Year Warranty - $1799

    http://www.ebay.com/itm/171867486373

  • I find I really have a problem with the way motion looks on this camera at times, for instance when doing pans it always seems to look stuttery like everything is shimmering. Changing shutter to 1/40 or 1/60 doesnt seem to help - is this to do with compression and if so will shooting to pro res recorder help?

  • I haven't noticed that much when panning. Are you using an image stabilized lens with the stabilizer on? Sometimes panning confuses them.

  • "Sony Alpha A7S Mirrorless Digital SLR Camera Body + 1 Year Warranty - $1799"
    $700 different compare to big seller, so tempted to buy but too late -;)

  • @tinbeo

    It is out of stock already.

    Most probably it is non US model, import.

  • Tinbeo, Buyer BeWare! The one advertise may have been "sold" before the ad was even released. Most of the time these "good" deals are bait and switch. They will try to "Upgrade" and never deliver the advertised product. They could be used product repackaged. Almost always "Grey Market". No US warrantee except their own worthless one. Incomplete package with no battery, charger, etc. Huge restock fee and/or other return hurdles when you find the camera defective.

    You would usually be better off buying a used/tested camera from a private party.

  • Tinbeo, Buyer BeWare! The one advertise may have been "sold" before the ad was even released. Most of the time these "good" deals are bait and switch. They will try to "Upgrade" and never deliver the advertised product. They could be used product repackaged. Almost always "Grey Market". No US warrantee except their own worthless one. Incomplete package with no battery, charger, etc. Huge restock fee and/or other return hurdles when you find the camera defective

    Why so much scary things at once?

    Grey market or not takes small time to check.

    I never actually saw camera sold by big seller and advertised as new with incomplete package or such.

    Instead I saw private sellers selling cameras with big issues and openly lie about it.