[LargeFormat] Turner Reich Orange Filters
Les Newcomer
largeformat@f32.net
Sat Jun 9 15:28:09 2001
Clive I pulled my Kodak filters publication B-3 out and looked at some
filter graphs
The standard #8 yellow cuts out at 460nm and has 100% transmission by 520nm
The # 12 is a Deep yellow and cuts out about 490nm and opens up at 540nm
This is also called a minus blue filter.
#15 is a deepr yellow than a 12 with the numbers shifting to 510 and 560
#16 is a light orange with a steeper cut off than a 15 520 and 560
#21 is an Orange filter with cutoffs points of 540 and 580
#22 is deep orange with cut off points at 550 and 600
You can see that as you progress from a #8 to a #22 you are simply
absorbing more blue and green light.
Since most of the films from the early 20th c. were very blue biased I
have to wonder if TR didn't over prescribe the yellow filter so
customers would get more dramatic effects, thus claiming TR lenses to be better.
Les
Clive Warren wrote:
>
> Some time ago we discussed Turner Reich 4x5 lenses - some people love 'em
> some have had bad experiences....
>
> Think it was Ken Hough who has great things to say about them. It seems
> that bad experiences may have been due to the fact that the lenses need to
> be refocussed when stopped down and that they should (always?) be used with
> an orange filter which was supplied with the lenses when new. This is when
> using both lens groups together in addition to single lens groups for the
> longer focal lengths.
>
> Hardly an APO lens - however apparently capable of excellent performance as
> they are a protar design with an additional element to avoid being sued I
> guess .......
>
> If Ken is listening then perhaps he can enlighten me - or maybe someone
> else knows - would like to find out the Wratten number equivalent of the
> original orange filter. Can anyone help?
>
> Cheers,
> Clive
>
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