White dots appearing in film after exporting

[sowden_jd]

Hi everyone!

I consider myself quite green when it comes to coloring a film. I just made a short film and upon exporting, I noticed white dots randomly popping up on screen. Any ideas why? I did usual color correcting from Log shot footage, then added only a 20% opactity Lut on top. It seems to be only the footage towards the end of my 20 minute film. I attached a photo for a reference example. 

Was all shot in 1080p and exported in high quality 1080p. 

 

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[R Neil Haugen]

I'm not seeing any white dots ... this is 'expanded' enough I'm seeing what seem to be actual pixels, with some amount of video noise present.

I've a lot of experience with color in Premiere ... but what's a "20% opacity LUT" ? As a descriptor, I'm a bit puzzled.

Neil

[sowden_jd]

Hi Neil!

Thank you for replying! Apologies about that.

I put an adjustment layer overtop of all the footage and added a pre-made LUT to it. Adjusted the amount of the lut color by adjusting the adjustment layer opacity so it was not as strong. 

I know they do not look like much here, but if you expand it you can see. My fear is when this reaches a movie screen, it will be very obvious. Especially if I can notice it on fullscreen computer monitor. 

Here are some better references.

 

 

[sowden_jd]

This is also a low quality export. Sorry for that but all I have on hand. Clearer white dot (or pixel) in 1080p. 

[R Neil Haugen]

I'm wondering if the LUT is simply making a bad pixel in the film more obvious.

Take the same frame, without the LUT active, and raise contrast some. See if the pixels are showing the same in the same place.

Neil

[sowden_jd]

I think you just helped me narrow it down. Is it possible for that to come from the camera? 

Here is a shot with LUT off and all color correction gone.  

[R Neil Haugen]

Yes, you can have bad pixels in a camera, or alternatively, have a dust spot.

A dust spot will be seen on every frame 'while it lasts'. Some cameras do a shake-thing to clean sensors so you can have a dust spot for a part of a shoot, then turn the camera off and back on later and it's gone. If there's no auto-cleaning action of the camera, they're there until you get the sensor cleaned. Typically dust covers more than one precise pixel though.

Bad pixels are just there. Normally pretty hard to see while an image is playing though.

Neil

[sowden_jd]

I cannot thank you enough, Neil! Have a great night and stay safe!