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So I have rendered an Image Sequence and created a video of those images. Suddenly I realised that if I had only one image (shot by a camera or created with Blender) I would now go to Photoshop and do some colour correction (for instance set a white and a black point).

How best to do this with videos? Is it possible to color correct the whole Image Sequence in Blender or is that to be done in another software (like Adobe Premiere)?

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    $\begingroup$ Related: blender.stackexchange.com/q/2105/2843 $\endgroup$ – Samoth Mar 22 '16 at 22:29
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    $\begingroup$ Also related: blender.stackexchange.com/questions/42649/… $\endgroup$ – p2or Mar 23 '16 at 9:47
  • $\begingroup$ why is this a bad question ? $\endgroup$ – Old Man Mar 23 '16 at 11:04
  • $\begingroup$ Where ever you choose to do the color corrections make sure that you use the image analysis tools in the UV?Image editor window in the Tools tab. Or in the VSE see the scopes icons in the VSE preview window. $\endgroup$ – 3pointedit Feb 9 '18 at 12:03
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Yes, you can do color correction in both the compositor, and in the color management tools of the Scene Tab.

I would use the Scene Tab option for Black and White, as it is pretty simple to do.

My recommendation would be to render one frame, get this set the way you like it in the UV/Image Editor, and then render your sequence.

enter image description here

Here's a look at the compositor (NOTE for just B&W adjustments, BrightContrast Node might be all you need). For rendering an existing Image Sequence change your Input to Image Sequence. If you want to influence color there is a Color Balance node just for this reason (although you could just play with grayscale values here as well). This is a huge topic, so this is not definitive, just a good starting point. You could use all sorts of things like color ramps, blurs, etc... to get the "LOOK" that you are going for.

If you find that you need to animate the color balance at any point in your timeline, you can keyframe any slider value by hovering your mouse over that value and hitting I as well.

enter image description here

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  • $\begingroup$ Also set white/black points ? Because that is the one thing I always start with when editing still images $\endgroup$ – Old Man Mar 22 '16 at 23:13
  • $\begingroup$ Thanks, I will explore these color management tools. Could you maybe give some ideas how this can also be done in the compositor ? $\endgroup$ – Old Man Mar 22 '16 at 23:30
  • $\begingroup$ @JanScherders I just appended my answer to address your request. $\endgroup$ – Rick Riggs Mar 23 '16 at 0:16
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Via the Video Sequence Editor

Import your Image Sequence into the VSE and in the Properties Modifiers Panel with your Strip selected you can add a Strip Modifier for your whole Image Sequence like a Color Balance or a White Balance Modifier.

Modifiers Panel

You could copy them to other Strips if needed selecting Replace or Append now since 2.77.

In the White Balance Modifier you can pick a Color from your Sequencer Preview to set a White Level:

White Balance Modifier Color Picker

All pixels will then mathematically be divided by this choosen color.

Apart from that, the Bright/Contrast Modifier might help you with the blacks. Or when you use a Curves Modifier, you can easily boost your black level when you lift the bottom left part of the curve:

Curves Modifier with lifted Black Level

Unfortunately, the Curves Modifier for Strips doesn't have the White and Black Level Color Choosers as the RGB Curves Node does - where you can set exactly what you want.

RGB Curves Node

But this RGB Curves Node is only available in Compositing via Nodes. So You might consider using one of the VSE to Compositing Add-ons for this:

Alternatively via Compositing

To use only nodes you might set your frame range to the length of your Image sequence, make sure, in the Post Processing Panel in your Properties' Render Tab you have only Compositing selected, check Use Nodes in the Compositing Node tree, remove the Render Layers Node and add an Input > Image Node instead. Set it to Image Sequence and set its frame range accordingly. Put the Color > RGB Curves Node between it and the Composite Node and hit Animation (F12).

Compositing Node Setup

(You might have to delete your default camera to prevent Blender rendering your Default Scene again and again, but I think it shouldn't do that when you delete that Render Output Node)

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  • $\begingroup$ I will dive into this. Thanks. Can you also set white / black points because that is one thing I have not seen in Blender ( or did I not search enough) ? $\endgroup$ – Old Man Mar 22 '16 at 23:11
  • $\begingroup$ @JanScherders: I added some more details about the other Modifiers and mentioned a second possibility via the Compositor. That should help you out. $\endgroup$ – Samoth Mar 23 '16 at 11:35
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    $\begingroup$ The VSE, again, is an extremely poor choice for colour grading for a number of reasons too long to list here. Proper grading should be done in a compositor, with strict control over the transforms for your primary and secondary grades. $\endgroup$ – troy_s Mar 24 '16 at 4:29
  • $\begingroup$ I am new to Blender and wanting to change Black and white arrears in a video to colour which found hard to find information on and can confirm in following the above heading "Alternately via Compositing" instructions it can be done. Get to the picture stage in the above and click either the white level or black level on the RGB curves node to bring up its colour chart. click on the small dot and move it around the outer edge with the cursor and you will see it go through the different colours in your video clip. Many Thanks Rick Riggs for the answer. $\endgroup$ – user40792 Jun 28 '17 at 14:12

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