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causio
Joined: 19 May 2006 Posts: 6 Location: London
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Posted: Sun Jun 25, 2006 10:00 pm Post subject: |
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I,ve managed to find some of these filters for my speed graphic.Can anybody please tell me where I can find the compensation factors.Regards Dave M |
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Henry
Joined: 09 May 2001 Posts: 1648 Location: Allentown, Pennsylvania
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Posted: Mon Jun 26, 2006 12:54 pm Post subject: |
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Tell us which ones you have, maybe we can help. The only lists I have are in out-of-print pamphlets and guides. At a camera shop you might be able to find a brochure from a current maker such as Hoya; these usually give the factors. |
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causio
Joined: 19 May 2006 Posts: 6 Location: London
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Posted: Mon Jun 26, 2006 2:31 pm Post subject: |
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Ah of course but thought it might be simple like a nice website somewhere.Anyway these are ones I have.Red marked A.Yellow K2.Reddish? 85B.All series 7.Thanks Dave |
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Jack5541
Joined: 31 Jul 2003 Posts: 76
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pv17vv
Joined: 22 Dec 2001 Posts: 255 Location: The Ardennes, Belgium
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Posted: Mon Jun 26, 2006 5:12 pm Post subject: |
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For panchromatic " modern " film like Tri-X, from Graflex photography 1948 :
A : daylight 4, tungsten 2
K2 : daylight 2, tungsten 1.5
85B : used for Kodachrome = nice display item
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Henry
Joined: 09 May 2001 Posts: 1648 Location: Allentown, Pennsylvania
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Posted: Mon Jun 26, 2006 6:47 pm Post subject: |
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From Kodak Master Photoguide (1966; agrees with 1954 ed.), for panchromatic film:
K2 - daylight 2, tungsten 1.5
A - daylight 8, tungsten 4
Filter factor "2" means "double the exposure", ie., open up one f-stop, OR halve the shutter speed. Factor "8" means open up three f-stops, OR divide shutter speed by 8 (eg., 1/200 becomes 1/25).
[ This Message was edited by: Henry on 2006-06-26 11:48 ] |
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causio
Joined: 19 May 2006 Posts: 6 Location: London
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Posted: Wed Jun 28, 2006 7:45 pm Post subject: |
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Thaks very much.Dave |
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Murray@uptowngallery.org
Joined: 03 Apr 2002 Posts: 164 Location: Holland MI
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Posted: Tue Sep 12, 2006 5:33 am Post subject: |
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A is same or close to same as 25, right?
Wouldn't the 85B still be useful as an orange contrast enhancer with B/W? I don't think one need only use the 'classic' colors for b/w.
I have a number of filters I originally thought were useless because the films were no longer made, but that still have an effect, so I kept them. Unfortunately, some of the Series filters I have have wrinkles/reticulations on them...I guess they weren't made to last forever.
_________________ Murray |
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Henry
Joined: 09 May 2001 Posts: 1648 Location: Allentown, Pennsylvania
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Posted: Tue Sep 12, 2006 3:11 pm Post subject: |
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Right, 25 = A (red) filter.
85B is for converting Type B color film, balanced for 3200°K, for use in daylight. Used as a contrast filter with b/w, I suspect it would follow the principle laid out in the Kodak Master Photoguide (ed. 1954, p. 23): "Contrast filters lighten (in the print) colors similar to the filters, darken those complementary to the filters."
On the subject of longevity, the Guide has this to say (p. 21): "Note 1 - The Kodak Wratten filters 85 and 85B currently being manufactured have improved stability. If filter being used is several years old, its replacement is suggested." Hmm, time to stop by your nearest Wratten series filter supply store and stock up on those improved ones!
[ This Message was edited by: Henry on 2006-09-12 12:47 ] |
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