Very noisy blues

[Appleguy]

Shooting some footage with the red in specific conditions certain fluorescants for example made the picture give out incredibly noisy blues. Does anytbody know of a way of rectifying this in camera without having to grade it out later?
Also is this related to the IR issue?

Thanks

 

[Dan Hudgins]

Defocus

Defocus

If you can't use more fill light, in post you can use my sharp/soft filter to blur the blue image and adjust the curves, that helps reduce the blue spots. More fill light should also help, you can gel the fill light to match better. You can also try a FL-D or FL-B filter and use the special FL matching gels for the lights to get more centered color light into the camera, a UV filter could be added as well. If you have enough light try an 80 series plus a FL-D maybe?

 

[Donald G]

Black Shade again. It helped me when I had a ton of noise in the blacks and blues. Give it a shot.

 

[Tim Sutherland]

As Dan said, filters in camera go a long way to fixing this issue. Then of course you need more light, but that's the nature of the beast.

 

[jbeale]

I don't know about fluorescents, but I know there are some kinds of metal-halide lamps (used in some gyms, for example) that have almost no blue component at all. If you try to white balance in that case, you'll end up with a huge gain-up compensation and get very high noise levels in the blue channel (with any camera).

 

[Esteban Sosnitsky]

Make sure your exposure is right. Underexposure brings up the noise dramatically.

 

[Jochen Schmidt-Hambrock]

I don't know about fluorescents, but I know there are some kinds of metal-halide lamps (used in some gyms, for example) that have almost no blue component at all. If you try to white balance in that case, you'll end up with a huge gain-up compensation and get very high noise levels in the blue channel (with any camera).

So you dont white balance? Or manual white balance to a higher temperatur?

All the best,
Jochen

 

[Zorie Barber]

what's Black Shade"? I have the same challenging blues in some dark shots.

best

Zorie

 

[HD Hildebrand]

If you can't use more fill light, in post you can use my sharp/soft filter to blur the blue image and adjust the curves, that helps reduce the blue spots. More fill light should also help, you can gel the fill light to match better. You can also try a FL-D or FL-B filter and use the special FL matching gels for the lights to get more centered color light into the camera, a UV filter could be added as well. If you have enough light try an 80 series plus a FL-D maybe?

"sharp/soft filter to blur the blue" what does this mean - you have a filter? Went to your web page but my limited brain power could not figure it out.

 

[J. Eric Camp]

What's black shade?

Well it would be something you have to do before you shoot to matter, so if you have footage that you want to "fix" black shading will do you no good.

Dan is developing his own program, that is what he is referring to. Past that what he is saying is if you separate the blue channel and put some softening on it you will smooth out the dancing noise some.