Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,886   Posts: 1,520,618   Online: 1046
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 16
  1. #1
    Donald Qualls's Avatar
    Join Date
    Jan 2005
    Location
    North Carolina, USA (transplanted from Seattle)
    Shooter
    Multi Format
    Posts
    1,845

    Alternate filter source and filter stacking

    I've located a source for very inexpensive filters that appear as if they'd be usable for multi-contrast, split-filter, and potentially even color printing (though color isn't a good option with my present cold light setup). That source is Lee Filters: http://www.leefilters.com/home.asp

    I'm in process of locating a local dealer, but it appears they sell a half sheet, 20x24 inches, for about $8, and they have filters that mimic CC spectra in red, blue, green, cyan, yellow, and magenta -- the ones I'm interested in, yellow and magenta, up to 50cc density. One half sheet will make about a dozen 6x6 inch above-negative filters -- pretty decent pricing! I understand that in order to get extreme high and low contrast with multigrade papers (ideally, I'd like to get from 00 through 5, but I'm not sure how much of that range will be realizable from a Zone VI cold light), I might need as high as 140cc -- am I correct in thinking that stacking multiple layers of filters would increase the density arithmetically? If not, is there a factor I could use? Alternately, where might one locate 00 and 5 filters in 6x6 inch for a good price, ready to use?
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  2. #2
    ann
    ann is offline

    Join Date
    Sep 2002
    Shooter
    35mm
    Posts
    2,859
    Images
    26
    at one time, one could buy 12x12 sheets of graded Ilford filters for printing at B&H. we got them to replace damaged filters and was cheaper to buy a full sheet and cut down to fit particular enlargers than buy a new set.

  3. #3
    Helen B's Avatar
    Join Date
    Jul 2004
    Location
    Hell's Kitchen, New York, USA
    Shooter
    Multi Format
    Posts
    1,557
    Images
    27
    Donald,

    You are correct: a CC10 plus a CC20 is the same as a CC30. As well as giving away the little swatchbooks for free, Lee et al offer larger 'Designer' swatchbooks, usually for a nominal price, but that seems to depend on the dealer. These are about 3" x 6" unfortunately. Maybe no good for this case, but possibly worth knowing about.

    Rosco also do CC equivalent filters. If I had to choose between Lee and Rosco, I'd generally go for Rosco because they seem to last longer. I've never done a proper comparative test, this is just an unscientific observation over the years I've been using them on hot lights so don't take it as gospel.

    Good luck with your search,
    Helen

  4. #4
    Helen B's Avatar
    Join Date
    Jul 2004
    Location
    Hell's Kitchen, New York, USA
    Shooter
    Multi Format
    Posts
    1,557
    Images
    27
    "It took a while to find the bandpass charts with the Roscoe filters but they are on the site."

    A quick way to them is to go the the Rosco (sic) page I gave the link to and click on the little graph icons.

    Best,
    Helen

  5. #5
    Lee L's Avatar
    Join Date
    Nov 2004
    Shooter
    Multi Format
    Posts
    3,239
    Steve Anchell, p. 94 of The Variable Contrast Printing Manual, recommends the Roscoe [sic] 68 Sky Blue and 389 Chroma Green for split filter printing. He also discusses filtration options for different light sources to allow the maximum contrast range, with contributions from several people who have calibrated their systems.

    In addition, there is an appendix of paper and filter combinations that provide a good handle on just how much contrast control you get from many different combinations. A recommended book if you're trying to calibrate, and extend the possibilities with a given light source and VC papers.

    Look for the Rosco filters at an online theater supply company, or both B&H and Calumet have them in 20x24 inches. $5.65 at B&H, $7.49 at Calumet. Look for Rosco. not the misspelled Roscoe from Anchell.

    Lee

  6. #6
    David A. Goldfarb's Avatar
    Join Date
    Sep 2002
    Location
    Honolulu, Hawai'i
    Shooter
    Large Format
    Posts
    17,154
    Images
    20
    You can do this, but one attraction of the Ilford Multicontrast filters, is that there is ND built into the filters, so you can go from 0-3.5 without changing exposure, and add just one stop for grades 4-5.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
    Photography (not as up to date as the flickr site)--http://www.davidagoldfarb.com/photo
    Academic (Slavic and Comparative Literature)--http://www.davidagoldfarb.com

  7. #7
    Lee L's Avatar
    Join Date
    Nov 2004
    Shooter
    Multi Format
    Posts
    3,239
    Quote Originally Posted by David A. Goldfarb
    You can do this, but one attraction of the Ilford Multicontrast filters, is that there is ND built into the filters, so you can go from 0-3.5 without changing exposure, and add just one stop for grades 4-5.
    This is true, but the split filter approach, although more complex in some ways, allows finer gradations of contrast, and also provides the opportunity for more even grade spacing with papers that don't match the Ilford specs. It also can provide a greater contrast range in some circumstances, and one of those could be the use of a cold light head such as the Zone VI, which doesn't match the color temperature of the assumed frosted tungsten bulb to which the Kodak and Ilford filter sets are matched. More work, but more flexibility.

    Lee

  8. #8
    lee
    lee is offline
    lee's Avatar
    Join Date
    Nov 2002
    Location
    Fort Worth TX
    Shooter
    8x10 Format
    Posts
    2,913
    Images
    8
    I use the Lee filters Dark Blue and a Dark Green as a split filter option. The Dark Blue is the hard filter printer and the Dark Green filter is the soft filter printer. I start with a test strip using the green filter and look at the highlite and decide what time puts the tone in the highlite I want. Then I make a new print with the green filter and the time just found. Leaving the paper in place I change to the Blue filter and make a new test strip on top of the green filter exposure. I then select the blue filter time by looking at the shadow and seeing how it affects the over all contrast. I then make the third print using the green filter at the selected time and then the blue filter at the selected time. This should give you a good work print. Really simple.

    lee\c

    ps: looking at the lee filter site I am using Dark Blue #120 and Dark Green #124

    l\c
    Last edited by lee; 08-07-2005 at 03:47 PM. Click to view previous post history. Reason: more information

  9. #9
    Donald Qualls's Avatar
    Join Date
    Jan 2005
    Location
    North Carolina, USA (transplanted from Seattle)
    Shooter
    Multi Format
    Posts
    1,845
    Lee, are you able to get very hard and very soft grades with single layers of those filters, or are you using mutliple layers? Also, I've understood that magenta and yellow are preferable over blue and green because the red light, while not affecting the paper, makes the image much brighter to the eye for focusing (which is best done with the filter in place, at least with the filter below the lens; in my case, it may not matter).

    What I had in mind was to stack three layers of the magenta and yellow 50cc filters to get a maximum hard and maximum soft, and work from there. As pointed out above, split filtering will give me much more control with the cold light -- perhaps even take away my current longing to find condensor glass and go back to the tungsten light I know from printing 20-30 years ago.

    Oh, and the Lee filters, while about a dollar more per sheet, are available from a local dealer; I can save $10 or so on shipping and have them in my hands the day I have the money. I'm almost through chasing light leaks, have a fresh box of 8x10 RC multigrade paper (and a couple 40+ year old boxes of snapshot size Velox and Dupont, heaven only knows if they're still any good), plan to mix my Dektol on Friday, and should be able to print (for the first time since 1981) this coming weekend.
    Photography has always fascinated me -- as a child, simply for the magic of capturing an image onto glossy paper with a little box, but as an adult because of the unique juxtaposition of science and art -- the physics of optics, the mechanics of the camera, the chemistry of film and developer, alongside the art in seeing, composing, exposing, processing and printing.

  10. #10
    Lee L's Avatar
    Join Date
    Nov 2004
    Shooter
    Multi Format
    Posts
    3,239
    Donald,

    The recommended blue and green filters for split filter VC printing are primary additive filters, similar to the #58 or #61 greens and #47B Wratten filters. Since these are practically full cutoff outside their passbands, each should give you as close as possible to the maximum isolation of either the high contrast or low contrast emulsion layers in the paper. Of course this will vary to some degree with the paper in question, as their spectral sensitivity varies, but it should hold in general, and so shouldn't require that you stack identical filters for increased effect.

    As for easier focusing with the red light included, I don't think that will matter too much, and you wouldn't want to shift focus when changing filters in split printing anyway. If you're using a decent enlarging lens a stop or two down from wide open, you should be able to focus in white light and then put in the filters, especially if they're above the film. Even quality CC gels below the lens shouldn't have that great an effect. Seems I recall an article somewhere that had to do with focus shift with enlarging filters, maybe by Gainer if memory serves, but it's been a while. In any case the finding was that there was an insignificantly small shift in focus with filters in place. If you'd feel better about focusing with filtration in place, focus with the green, near where your vision peaks, then use that for the blue as well. That's probably the route I'd take.

    BTW, VC papers vary all over the place, and some require more than 150CC magenta for maximum contrast. Just to give you an idea, Anchell lists Agfa VC papers as needing 80-90CC magenta for maximum contrast and Ilford MG IV RC Deluxe and MG FB need 200CC M to reach maximum contrast. Split blue/green printing seems to me the most versatile approach across a range of papers.

    Just for the record, I'm currently printing split with the "end of range" filters from the Kodak and Ilford filters that I have on hand, which are 20+ years old, and don't include the newer extremes. I plan to get some blue/green filters soon, but don't have them yet. I'm getting back into the darkroom after a hiatus of some years, but only about 10 or 12 in my case. I used to print about 2000 custom B&W's a month on Kodak RC II and III, and could guess to a half-grade by looking at the neg. Don't think I could do that now without a little practice. But I'm not exposing and running 20 prints an hour now either.

    Good luck and have fun getting back into the darkroom. It's still magic in the end, even if you know what you're doing.

    Lee

Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin