# DOES TWO 1/2 CTB's = ONE FULL CTB???????

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### #1 Daniel Porto

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Posted 11 September 2008 - 12:59 PM

Does putting two 1/2 CTB's (half blues) together equal the same color temperature as a full CTB?? Some people have told me that this is true, others have told me that it only lowers the light. Im sure that it lowers the light and although two 1/2 CTB's might not equal a full CTB exactly, I imagine that it would be quite close (in terms of color temperature).

Would this be the same for CTO????

Thanks
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### #2 Darryl Richard Humber

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Posted 11 September 2008 - 01:21 PM

It's very common to combine two halfs to make a full or two quarters to make a half if you don't have the degree you need.
Would this be the same for CTO????

Yes. It happens all the time
Thanks
[/quote]
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Posted 11 September 2008 - 03:36 PM

I would say it's close enough not to worry, though, if memory serves right the MIRED values of a full CTO and the combined of 2 1/2 CTOs is slightly different. This may also depend on brand.
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### #4 Chris Pritzlaff

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Posted 11 September 2008 - 04:25 PM

you can get a swatch book from any of the gel manufactures that have the specs on each of the gels. I don't have one in front, but IM pretty sure that doubling up on 1/2 is not exactly full strength, but its always been close enough for me to work with.

Again check the books for the mired shifts of each gel and that should answer all your questions

1/2 CTO + 1/2 CTO = Full CTO?

http://www.cinematog...n...44&hl=mired
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### #5 Daniel Porto

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Posted 11 September 2008 - 06:56 PM

THANKYOU EVERYONE!
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### #6 Chris Keth

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Posted 11 September 2008 - 08:20 PM

I see Chris already linked to my old post about the same thing. They don't add up to the right thing technically but it's close enough to not worry about it.
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