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  1. #11
    jd callow's Avatar
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    Quote Originally Posted by Mike1234 View Post
    If I recall correctly, Ed has it right with the Wratten 44. I have a whole box full of Kodak Wratten gels stuffed away somewhere and I might have some information with them. I'll try to find them.
    I believe that the Wratten 44 is a minus red filter and therefore would be close to Ortho, but it may still allow yellow through. Adding Gels to the lights won't be the same as the idea is cut off red and yellow bandwidths as gels on lights won't keep those colours from reaching the film.

    I'm not sure if my earlier advice recommending a cyan filter is the same thing. I think what needs to be done is to compare the spectral sensitivity of ortho to the masking/pass through ability of a given filter.

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  2. #12

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    A Wratten 44 is a deep cyan filter. Cyan is opposite of red so it indeed does block most red. I don't think it will pass much yellow either. We were talking about using the filter at the lens... at least I assumed this.

  3. #13
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    Mike
    With regard to my comment on putting gels on lights I was referring to an earlier post where the poster asked if this was a viable alternative. The Wratten 44 may have some blue in it, but I suspect that it is not a minus yellow which is what I believe would be needed in conjunction with a minus red to achieve an ortho look. I could be wrong as i do not know what exactly ortho is sensitive to nor do I know what exactly a Wratten 44 will block or pass.

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  4. #14
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    I think a green filter used to be specified for this purpose. It's been a long, long time. A green filter will keep red roses in green foliage from looking like garbage.
    Gadget Gainer

  5. #15

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    JD... ahh yes, forgot about the post asking about filtering the lights.

    With regard to the #44 passing yellow, going from memory (not reliable anymore), it blocks most yellow as well as red light... close enough anyway. A green filter passes quite a bit of yellow light and bright red turns very dark (even black-ish) depending on how deep red the rose is and how deep green the filter is. I know there was a #58 deep green but I can't remember if there were darker ones... maybe a #61??
    Last edited by Mike1234; 08-12-2009 at 03:49 PM. Click to view previous post history.

  6. #16

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  7. #17
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    Quote Originally Posted by Mike1234 View Post
    Thank you, that makes the discussion in this thread much more clear.

    Steve
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  8. #18

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    Quote Originally Posted by Mike1234 View Post
    Looks like a #47A would be the best choice, as opposed to the blue I recommended earlier. It passes 380 - 520 nM instead of 400 - 470 nM like the #47B.

    I use an 80A for a blue filter. I guess it is because I am cheap, and I already have it.
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

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  9. #19

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    I might have a 47A. I've been searching for my Wratten filter box to look for other filters but I haven't located it yet. I'll try again tonight.

  10. #20
    jd callow's Avatar
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    Again we would need toknow what Ortho is sensitive to, but it appears that the 47 (410-500) more closly covers the area I understand as being the portion that Ortho is blind to Yellows through red .
    Last edited by jd callow; 08-12-2009 at 05:40 PM. Click to view previous post history.

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