![]() However the limited dynamic range may mean that very bright or very dark objects cannot be accurately reproduced as these may exceed the gammas dynamic range. So the contrast on the TV screen will match the contrast of the scene being filmed and the picture will look “normal”. This way the contrast range of the camera and the contrast range of the display will be matched. Normally the gamma curve used in the camera is designed to match the gamma curve used by the TV or monitor. The contrast on the TV or monitor will however be correct as the camera captures the same contrast range as the monitor is able to display. When shooting a high contrast scene with conventional gamma the brightest highlights and the darkest shadows cannot be recorded. ![]() Normal television gamma has a limited dynamic range (about 6 to 7 stops) and as a result also has a limited contrast range. Many modern cameras can capture a brightness range, also known as dynamic range, that far exceed the Rec-709 standard.Īs gamma effects the dark to light range of the image, it also effects the contrast of the image. This gamma curve is based on standards developed over 60 years ago and camera technology has advanced a lot since then! Even so, almost every TV and monitor made today is made to the Rec-709 standard or something very similar. When TV was first developed the gamma curve in the camera made the signal small enough to be broadcast by a transmitter and then the gamma curve in the TV set (which is the inverse of the one in the camera) expanded the signal back to a normal viewing range. The current standard for broadcast TV is called “Recommendation BT-709”, often shortened to Rec-709. The gamma curve is there to make the images captured easier to manage by making the file size smaller than it would be without a gamma curve. One of the really nice features of the Sony A7s is the ability to use different gamma curves and in particular the Sony S-Log2 gamma curve.Īll conventional cameras use gamma curves. If you find this useful please consider buying me a coffee or a beer. ![]() LUT’s to accompany this article can be found here. It is based on my own findings having used the camera and tested various exposure levels and methods. This is where I am wondering if you are getting confused.This document has been prepared independently of Sony. The upper is Source Color Space and the bottom is Color Transform. In Source Settings / Color Encoding there are two adjustable areas. You will need to use the Refresh Color Adapters to see the result of this action in the sequence. So you can delete what Avid guessed and substitue a different one. You CAN burn it into the footage during transcode operation if you wish.Īs Dom said, it is possible that Avid is not getting the right info from the clips as to what LUT to use. This does not get "burned in" to the footage. This allows the footage to basically look like what the camera saw. So Sony S-log 2 should get a S-log 2 to Rec709 LUT. When log footage comes into Avid, if you have the Color Management Settings set to Insert Color Transforms Automatically, then Avid attempts to identify what the native log type is present and then add necessary LUTs so that what you see in viewer looks correct for the color space you have chosen for the project. It is possible that all is ok and there is just some confusion going on. To be precise the ‘source colour space’ is identified as rec709 in the top of the source settings window - which is incorrect Our problem is The footage comes in identified as rec709 when it should be identified as s-log2.
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