Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,699   Posts: 1,549,146   Online: 1130
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 16
  1. #1

    Join Date
    Jun 2005
    Shooter
    4x5 Format
    Posts
    3

    Using 8x10 contact printer with 20W screw-in BL fluorescent bulbs.

    Hi all. I wonder if any of you are using a Rexo 8x10 Master Contact Printer model 3 mfg. by Burke & James for alternative processing.
    After reading an article by Sandy King, I would like to try Kallitypes.
    My printer has 7+1 screw-in round light bulbs. Three in the centre row, two on the right and two on the left (+ one off centre, very dark, which I do not know what the use is).
    I was thinking to change them for screw-in 20W Blacklight Fluorescent bulbs. The space between top of bulb and glass is about 6" (16cm). On the beginning I would use it mainly for 4x5 printing.
    This contact printer does not have any fan for cooling. I wonder if I would have to add one.
    I would like to get your opinion on whether or not this could work.
    Thanks Jacek

  2. #2
    Donald Qualls's Avatar
    Join Date
    Jan 2005
    Location
    North Carolina, USA (transplanted from Seattle)
    Shooter
    Multi Format
    Posts
    1,845
    The off-center bulb is for a safelight bulb, used in setting up with silver gelatin contact printing papers to ensure the negative, any mask, and paper are all correctly aligned on the glass. Probably unnecessary with platinum and other UV sensitive processes, since you can set up in subdued room light.

    Incandescent BL bulbs will print, but likely no faster than unfiltered bulbs would (think multi-day exposures); the coating merely subtracts the visible light so you can see the effects of the tiny fraction of the light emitted by the tungsten filament in the near UV. You'd most likely get much, much faster printing if you can locate compact fluorescent bulbs with a "daylight", "grow-light" or similar broad spectrum coating, or even CF BL bulbs (I've never seen such, but can't decide why they haven't appeared, given there's a market for the very, very weak incandescent BL bulbs). Even ordinary kitchen type CF bulbs will probably print faster (and run cooler, and use less energy, and last longer) than incandescent BL.
    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.

  3. #3

    Join Date
    Dec 2002
    Shooter
    Large Format
    Posts
    6,242
    Quote Originally Posted by Jacek Luc
    Hi all. I wonder if any of you are using a Rexo 8x10 Master Contact Printer model 3 mfg. by Burke & James for alternative processing.
    After reading an article by Sandy King, I would like to try Kallitypes.
    My printer has 7+1 screw-in round light bulbs. Three in the centre row, two on the right and two on the left (+ one off centre, very dark, which I do not know what the use is).
    I was thinking to change them for screw-in 20W Blacklight Fluorescent bulbs. The space between top of bulb and glass is about 6" (16cm). On the beginning I would use it mainly for 4x5 printing.
    This contact printer does not have any fan for cooling. I wonder if I would have to add one.
    I would like to get your opinion on whether or not this could work.
    Thanks Jacek
    Since you did say fluorescent BL I will assume that you mean the bulb that Sandy King and others have used for exposing Azo. I would assume that from what I have heard about that particular bulb that this may work for you. I personally have not used that bulb but I have used the F15T8BLB lamp and it works fine.

    The BLB incandescents are an entirely different matter...I have used those and they will not expose Azo and hence would be even worse on alt process.

    Regarding your question about a fan, I can not answer your question other then to say that for an equivalent wattage the fluorescent lamps are usually much cooler. If you decide to try the lamps that you mention, I would just wait until I tried it before I decided on a fan.

  4. #4

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by Donald Qualls
    Incandescent BL bulbs will print, but likely no faster than unfiltered bulbs would (think multi-day exposures); the coating merely subtracts the visible light so you can see the effects of the tiny fraction of the light emitted by the tungsten filament in the near UV. You'd most likely get much, much faster printing if you can locate compact fluorescent bulbs with a "daylight", "grow-light" or similar broad spectrum coating, or even CF BL bulbs (I've never seen such, but can't decide why they haven't appeared, given there's a market for the very, very weak incandescent BL bulbs). Even ordinary kitchen type CF bulbs will probably print faster (and run cooler, and use less energy, and last longer) than incandescent BL.
    Donald,

    He is not talking about using incandescent BL bulbs but coiled fluorescent tubes that screw into incandescent fixtures. Watt for watt they put out the same amount of UV radiation as regular tubes.

    Sandy

  5. #5
    TheFlyingCamera's Avatar
    Join Date
    May 2005
    Location
    Washington DC
    Shooter
    Large Format
    Posts
    8,391
    Blog Entries
    51
    Images
    438
    Quote Originally Posted by sanking
    Donald,

    He is not talking about using incandescent BL bulbs but coiled fluorescent tubes that screw into incandescent fixtures. Watt for watt they put out the same amount of UV radiation as regular tubes.

    Sandy
    Sandy- do you have a source for those bulbs? I haven't seen them at Home Depot or Lowes.

  6. #6

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by TheFlyingCamera
    Sandy- do you have a source for those bulbs? I haven't seen them at Home Depot or Lowes.
    I have not seen them locally either.

    Here are a couple of sources.

    http://www.coolstuffcheap.com/fluorscrewin.html

    http://www.saveonlighting.com/itemdetail.asp?item=1091


    Sandy

  7. #7
    Donald Qualls's Avatar
    Join Date
    Jan 2005
    Location
    North Carolina, USA (transplanted from Seattle)
    Shooter
    Multi Format
    Posts
    1,845
    Oops, guess I need to read more carefully. I'd never seen or heard of a CF version of a BL fluorescent (as I said above) until this thread -- I'll bookmark those sources, since I can see those as the easy way to make a UV printer (no ballasts to buy, just install sockets in the correct pattern and set up a cooling fan). Of course, $72 for just the bulbs makes me shudder a bit (not even counting the sockets and the box to mount it all, and then the contact frame on top), but still a lot cheaper than buying ballasts and doesn't require me to become an instant expert in wiring fluorescents...
    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.

  8. #8

    Join Date
    Mar 2005
    Shooter
    ULarge Format
    Posts
    868
    Images
    24
    I am in the proceess of building a UV light source using BLB tubes. I was a little hesitant to go with the build from scratch method, simply because I don't like wiring--even though I have done some in the past. In Sandy's excellent article on UV light sources, he describes using prewired fluorescent light strips for building a unit. I followed up on that idea and started pricing units at Home Depot.

    I found Commecial Electric Shop Lights with instant on electric ballast which fit my needs. Each shop light is ready to plug into the wall out of the box. When I got one home, I took the metal plate off the top to examine the insides. Everything is pre-wired. The only problem with the prebuilt unit is that the lights are too far apart. My solution, take the bi-pins, wiring and ballasts out of the pre-built unit and put them into a wooden frame to size. To do so requires removing six sheet metal screws. I get the advantage of having the bulbes closer together, and I don't have to do any wiring.

    I rechecked at Home Depot to see about the cost of buying the parts individually and assembling them. Guess what, it is cheaper to buy the pre-wired unit than to build from scratch. I purchased the 48" unit form Commercial Electric. I don't know if they make a 24" unit. It would be worth looking into if you want to use 24" tubes.

  9. #9

    Join Date
    Jun 2005
    Shooter
    4x5 Format
    Posts
    3
    Thanks for the reply.
    The bulbs I am talking about are listed on the website www.starmgc.com/theatre.html
    Name of the company is Star Light & Magic. The reference for that bulb is F60U. It is a 20 W UV Fluorescent Blacklight. Screws into a standard socket. Cost 16.95$.
    Donald what do you think would be the correct pattern for setting the bulbs? And how much space between them.
    Jacek

  10. #10

    Join Date
    Mar 2003
    Location
    Greenville, SC
    Shooter
    Large Format
    Posts
    4,813
    Images
    5
    Quote Originally Posted by Allen Friday
    The only problem with the prebuilt unit is that the lights are too far apart. My solution, take the bi-pins, wiring and ballasts out of the pre-built unit and put them into a wooden frame to size. To do so requires removing six sheet metal screws. I get the advantage of having the bulbes closer together, and I don't have to do any wiring.
    Allen,

    My 48" UV bank is made of the two-tube fixtures. When I originally built the unit I found that the spacing was not ideal if you just placed the fixtures side by side. That left the outside tubes on adjacent fixtures much closer together than the two tubes in the fixture itself. I simply adjusted the unit by narrowing the distance betwen the tubes in each fixture. This involved nothing more than drilling a hole in the end of the fixtures for the new anchor position. It may sound complicated but in fact it was very easy and took very little time.

    Sandy

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