Mathew Collins Posted April 24, 2017 Share Posted April 24, 2017 Hi, Lee portal says, Full CTO Converts Daylight to Tungsten Light 6500K to 3200K1/2 CTO Converts Daylight to Tungsten Light 6500K to 3800K1/4 CTO Converts Daylight to Tungsten Light 6500K to 4600K1/8 CTO Converts Daylight to Tungsten Light 6500K to 5550K3/4 CTO Converts Daylight to Tungsten Light 6500K to 3600K http://www.leefilters.com/lighting/technical-list.html#&filter=conversion What would be the change in CT when we use these filters in front of a light with 5600K( say Arri PAR 4K) Please share your views. Link to comment Share on other sites More sharing options...
Michael Rodin Posted April 24, 2017 Share Posted April 24, 2017 Your HMI's color temp will be roughly 180 mired (= 1 000 000 / Kelvin CT). Then you find out the mired shift of a certain CTO and add it. Or subtract if it's CTB. More mired - less Kelvin - warmer Less mired - more Kelvin - colder Link to comment Share on other sites More sharing options...
Mark Dunn Posted April 24, 2017 Share Posted April 24, 2017 (edited) Full CTO mired shift is about 159. So the new CT will be 1000000/(180+159)=2950K. There's a chart on page 56 of the "Think Lee" download on that site under "resources". Just put a ruler across it. http://www.leefilters.com/lighting/lighting-resources.html Edited April 24, 2017 by Mark Dunn 1 Link to comment Share on other sites More sharing options...
Mathew Collins Posted April 26, 2017 Author Share Posted April 26, 2017 Full CTO mired shift is about 159. So the new CT will be 1000000/(180+159)=2950K. There's a chart on page 56 of the "Think Lee" download on that site under "resources". Just put a ruler across it. http://www.leefilters.com/lighting/lighting-resources.html Thanks much Mark and Michael. When I calculated the required Miredshift, for converting 5600K to 3200K using the formula, 1000000/3200 - 1000000/5600 =133 1000000/3200=312.5 1000000/5600=178.5714285714286 I could not find a filter with 133 Miredshift in the pdf. But almost near one is 285 (Three Quarter CTO) with a value +124. Would this calculation is correct? Link to comment Share on other sites More sharing options...
Premium Member David Mullen ASC Posted April 26, 2017 Premium Member Share Posted April 26, 2017 626 LED conversion gel (Seven Eighths Digital LED CTO) has a 132 MIRED shift value. Link to comment Share on other sites More sharing options...
Michael Rodin Posted April 26, 2017 Share Posted April 26, 2017 If you can't get it with one filter, use two. Or more. And if you want to apply a lot of correction to a big light (especially a PAR) it's better to add a couple spaced gel frames than a single dense gel. The so-called LED gels shift tint, not only color temp. They're for daylight LEDs only, on HMIs they can give magenta color casts. Link to comment Share on other sites More sharing options...
Mathew Collins Posted April 26, 2017 Author Share Posted April 26, 2017 626 LED conversion gel (Seven Eighths Digital LED CTO) has a 132 MIRED shift value. Would the LED conversion gel is OK for HMI PARs? Link to comment Share on other sites More sharing options...
Stuart Brereton Posted April 26, 2017 Share Posted April 26, 2017 There's no need to get hung up on correcting your lamps exactly according to the Mired system. Most people do perfectly well with Full, 1/2 and 1/4 CTO and Full ,1/2 and 1/4 CTB Link to comment Share on other sites More sharing options...
Mathew Collins Posted April 27, 2017 Author Share Posted April 27, 2017 There's no need to get hung up on correcting your lamps exactly according to the Mired system. Most people do perfectly well with Full, 1/2 and 1/4 CTO and Full ,1/2 and 1/4 CTB Hi Stuart, Thanks much. Now I got the answer. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now