Re: FILTER FACTOR FOR #52
Bob, according to the filter wheel I have (The negative Ansel Adams) #52 it's not mentioned but as others have suggested a starting point of 6 or 7X would seem reasonnable. A light meter or even a digital camera would also give you a fair starting point but you need to remember that each film as a specific response to light from a spectral point of view and this may translate to a somewhat and may be significantly different filter factor. In the end this mean that one should make a few test to make sure they have the right filter factor for the film under consideration. If you intend to digitize your negs you have much more room to play as long as your scanner can capture the density range you end up with on the neg, in other word you can over expose by as much as 3 stops if your scanner can read around 2.5D and even more stops if it can read around or above 3D and you will still be able to use the neg and edit the image to your satisfaction. But, if you use the negatif in the traditional fashion, you need to capture the density range required by you printing process, otherwise you may be unable to process and print the neg correctly. The traditional fashion is much less forgivin them the digital route as you surely know already. Regards, Yves ----- Original Message ----- From: "BOB KISS" <bobkiss@caribsurf.com> To: <alt-photo-process-l@usask.ca> Sent: Wednesday, July 09, 2008 8:51 AM Subject: RE: FILTER FACTOR FOR #52 > Thanks to all on Alt Photo who replied! > CHEERS! > BOB > > -----Original Message----- > From: Liam Lawless [mailto:lawless@bulldoghome.com] > Sent: Wednesday, July 09, 2008 12:01 AM > To: alt-photo-process-l@usask.ca > Subject: RE: FILTER FACTOR FOR #52 > > Bob, > > When I forget the factors of the many filters I have kicking around here, I > simply put the offending piece of glass or resin in front of the window of > my light meter and take a reading... then another without a filter. Works > pretty good! > > Wikipedia has an entry for 'Wratten Number' that lists all the commonly > available Wrattens, and 52 ain't there. Neither is it in the 'Filter > Substitution Table' in Wall & Jordan, where they have Wratten 11 and 23A as > light green (and 13 as medium green). No factors, though. > > Liam > > > > __________ NOD32 3254 (20080709) Information __________ > > This message was checked by NOD32 antivirus system. > http://www.eset.com > >
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