TMR Design wrote in post #3416224
Ok so here is the question. The ones you are suggesting are all boosting temperature. How does that help with the one strobe I have that is 'hotter' than the others?
I see one that's close to what I need. It's actually the first one listed and it converts 5500 degree to 4900 degrees. I need a change of about 500 degrees and that is 600 but it's the closest thing.
How precise is all of this and how precise do we need to be? Will that gel do the job I need?
The problem is that the color shift is not linear. It is different based on the color temperature you are starting from. The factor is expressed as the "Mired shift".
Mathematically, this is defined as:
Mired Shift = 1000 * (1000/T2 - 1000/T1)
where T1 is the color temperature you have and T2 is the color temperature you desire
The Rosco and Lee sites do not show the mired shift values for all "color conversion filters". However, the samples do supply the mired values.
For Roscoe CTB cinegels, they are:
# filter mired
3202 ctb -131
3203 3/4 ctb -100
3204 1/2 ctb -68
3206 1/3 ctb -49
3208 1/4 ctb -30
3216 1/8 ctb -12
3220 2x ctb -260
Hope this helps...
Ooops....just read that you may need to go in the other direction. Same rules apply, just need to use CTO filters. The Rosco site http://www.rosco.com/us/filters/cinegel.asp has mired values for the different CTOs.