Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,008   Posts: 1,524,581   Online: 970
      
Page 2 of 2 FirstFirst 12
Results 11 to 17 of 17
  1. #11

    Join Date
    Apr 2006
    Location
    Woking, Surrey, UK
    Shooter
    35mm
    Posts
    475
    Images
    27
    My uncle, who owns an electrical shop, ordered a 3W CFL lamp for me to try in a safelight. According to the packaging it is equivalent to a 15W conventional lamp.

    One safelight test coming up!

    Ian

  2. #12

    Join Date
    May 2003
    Location
    Valley Stream, NY
    Shooter
    Multi Format
    Posts
    3,216
    Go to an art store and get some rubylith. The stuff is designed to be used as a mask for orthochromatically sensitized materials - just like B&W photo paper. I have made a couple of safelight filters using a couple of layers of this stuff sandwiched between a couple of pieces of glass cut to the proper dimension. Works just fine after a proper safelight test. Of course, as with any safelight, it's only safe when used with dim light bulbs.

  3. #13

    Join Date
    Aug 2005
    Location
    Los Alamos, NM
    Shooter
    Multi Format
    Posts
    2,043
    The lamp size for a safelight depends on a lot of things: the filter, the distance from the light to the material, whether the illumination is direct or reflected, even the lamp itself. With Kodak filters, Kodak usually recommends a 15 watt inside frosted incandescent lamp for direct illumination at four feet. But other safelights work differently. I have a safelight for VC papers that uses a 20 watt standard cool white fluorescent tube. That's a bright lamp, and the safelight is bright, but it is perfectly safe at four feet. You should go by the manufacturer's recommendation. If you can't find that, use the Kodak rules (which are fairly conservative) as a starting point; then test the safelight. The inverse square law applies, of course, and you can use an appropriately larger lamp at greater distances.

    I would stick with the better known commercial products. The plastic you mention for a home grown safelight _may_ work, but different plastics vary a lot in their transmission, depending on the plastic, the dyes used, and the manufacturing process. If you usiig it, be sure to do some thorough testing. One additional possibility is to use a red LED cluster. You can get these with a standard lamp base. They are quite bright and perfectly safe for printing.
    Last edited by nworth; 12-30-2007 at 12:19 AM. Click to view previous post history.

  4. #14

    Join Date
    May 2006
    Location
    PO Box 231 New Underwood, SD 57761-0231
    Shooter
    Medium Format
    Posts
    189

    Safelights

    I gave up on red years ago, too harsh on the eyes. Since the advent of LED Christmas lights, I've found and have been using a set of yellow (35 light) string for several years now. Nice color that won't fog paper even after 10 minutes in the open. This would be the time to buy a set really cheep also. But since you have the red plexi already cut, pick up a pack of C-7 red or orange Christmas lite bulbs for 50 cents and a candleabra to edison base socket adapter and you've got safelights to go untill next Christmas.

  5. #15
    Sirius Glass's Avatar
    Join Date
    Jan 2007
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    13,021
    Quote Originally Posted by nworth View Post
    The lamp size for a safelight depends on a lot of things: the filter, the distance from the light to the material, whether the illumination is direct or reflected, even the lamp itself. With Kodak filters, Kodak usually recommends a 15 watt inside frosted incandescent lamp for direct illumination at four feet. But other safelights work differently. I have a safelight for VC papers that uses a 20 watt standard cool white fluorescent tube. That's a bright lamp, and the safelight is bright, but it is perfectly safe at four feet. You should go by the manufacturer's recommendation. If you can't find that, use the Kodak rules (which are fairly conservative) as a starting point; then test the safelight. The inverse square law applies, of course, and you can use an appropriately larger lamp at greater distances.

    I would stick with the better known commercial products. The plastic you mention for a home grown safelight _may_ work, but different plastics vary a lot in their transmission, depending on the plastic, the dyes used, and the manufacturing process. If you usiig it, be sure to do some thorough testing. One additional possibility is to use a red LED cluster. You can get these with a standard lamp base. They are quite bright and perfectly safe for printing.
    Good advise, except that I am asking about a ceiling light in a canister. The light goes on when the fan is turned on. Either I remove the bulb or I convert it into a darkroom light. A commercially available safelight will not work in this situation.

    Steve
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  6. #16
    Sirius Glass's Avatar
    Join Date
    Jan 2007
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    13,021
    Follow up:
    The cut red plastic disk using the plastic store's red plastic did not work with a 25 watt or 15 watt bulb. Now the red plastic appeared to be almost the same color as the safelight filter I had brought [the plastic store did not want to cut it since they did not know the cutting characteristics of the filter]. I know that what the eye sees and what the paper sees are not the same thing. The problem could have been all the light leaks around the fixture cover.

    I ended up taking the plastic store filter out of the canister and returning the safelight filter. I purchased a red bulb from FreeStyle and that solved the problem.

    Thanks for all the suggestions. I used the "old quarter on the photographic paper for five minutes" to do the testing.

    Steve
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  7. #17
    richard ide's Avatar
    Join Date
    Nov 2005
    Location
    Markham, Ontario
    Shooter
    Multi Format
    Posts
    1,214
    When doing the "coin test" Make an exposure on the paper with a negative without a safelight. Then place coins on the paper for varying lengths of time under the safelight. This way, the paper has received an overall exposure and will show small variations in exposure which may not show up the other way.
    Richard

    Why are there no speaker jacks on a stereo camera?

Page 2 of 2 FirstFirst 12


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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