Page 2 of 2 FirstFirst 12
Results 11 to 13 of 13

Thread: Fluorescent Grow Light Bulbs for alternative printing.

  1. #11

    Join Date
    Jul 2018
    Location
    Vermont
    Posts
    33

    Re: Fluorescent Grow Light Bulbs for alternative printing.

    Quote Originally Posted by Lisa K View Post
    NHE - can you please be specific as to what LED bulbs you have moved on to using that you feel have given you the results you are looking for, how many, and at what distance from your support you have placed them? Also, what exposure time have you been using? I have four fluorescent fixtures holding 2 bulbs each of F-40T12BL 40 Watt - T12 tubes (they are 48 inches). I have them about 5 inches away from the support. I make a digital negative with either Pictorico or Fixxons film and expose the cyanotype for 30 minutes. I am hoping to find a better "LED" bulb that makes my exposure go quicker.
    Quote Originally Posted by William Whitaker View Post
    +1, please.
    I use this led strip: https://store.waveformlighting.com/p...12527605252198

    I cut and soldered a 5m strip (of the 365nm) so the exposure area would cover my 11x14 printing frame. The strips come with adhesive so I just stuck them to a plywood board I had, in retrospect an aluminum sheet would have been better as they didnít stick all that well. The LEDs get warm but not hot enough that they need a heat sink.

    Exposure distance is approximately 2in as that was the closest distance where the beam spread appeared even. As to exposure time, a palladium print will get to maximum density in around 2min through an unexposed area of film and around 5min through a blank area of pictorico. I donít typically print cyanotypes but if I remember correctly the exposure time would be in the 10-15 minute range.

    I have focused more on using film lately, but my longest exposure has been around 60min. That was to get detail in an area of snow with a density of log 2.8-3.0. The LEDs are expensive so it was a tough decision, but it has been worth it when printing negatives with very dense highlights.

  2. #12

    Join Date
    Feb 2021
    Posts
    134

    Re: Fluorescent Grow Light Bulbs for alternative printing.

    Quote Originally Posted by NHE View Post
    I use this led strip: https://store.waveformlighting.com/p...12527605252198

    I cut and soldered a 5m strip (of the 365nm) so the exposure area would cover my 11x14 printing frame. The strips come with adhesive so I just stuck them to a plywood board I had, in retrospect an aluminum sheet would have been better as they didn’t stick all that well. The LEDs get warm but not hot enough that they need a heat sink.

    Exposure distance is approximately 2in as that was the closest distance where the beam spread appeared even. As to exposure time, a palladium print will get to maximum density in around 2min through an unexposed area of film and around 5min through a blank area of pictorico. I don’t typically print cyanotypes but if I remember correctly the exposure time would be in the 10-15 minute range.

    I have focused more on using film lately, but my longest exposure has been around 60min. That was to get detail in an area of snow with a density of log 2.8-3.0. The LEDs are expensive so it was a tough decision, but it has been worth it when printing negatives with very dense highlights.
    The 20W LED I use cost 1/10 this price and gets the same printing time at a distance of 12 inches. (I'm saying just the LED without the other equipment)
    Last edited by martiansea; 15-Jun-2021 at 20:54.

  3. #13

    Join Date
    Feb 2021
    Posts
    134

    Re: Fluorescent Grow Light Bulbs for alternative printing.

    I've gone back and found the details about my LED. I bought it from Taobao in 2018 (I was in China at the time) for 62RMB; less than $9. After getting back to the US, I ordered a Chanzon 20w 600mA constant current LED driver from Amazon for $8.81 and a cheap heatsink from Amazon for $14.99 (I wouldn't buy this particular heatsink again, the quality wasn't good. Better to order one from HeatsinkUSA, still inexpensive). A suitable AC power cord can be gotten for less than $5. All told, this package was put together for well under $40, and nothing else is necessary to use it for printing apart from figuring out a means to hang it above your work surface. At the moment, I have mine in my oven. It sits on the top rack and the work I'm printing sits on the bottom rack. If I need to get them closer together for some reason, I need only change the position of the rack. This sounds maybe crazy, but it works like a charm and the oven door does an excellent job of blocking the UV light. Of course I have to be careful not to forget it in there if I'm going to make a pizza!

    The Taobao listing for my LED said it is in the 380-385nm wavelength range. I'm getting very good printing results with this range; I printed all the pieces you see here with this LED: https://entropyandchaos.com/?portfol...ate-activities
    You can get an equivalent 385nm 20W LED from Amazon for $22.99, more than twice the price as from Taobao, but it's still dirt cheap compared to all the prefab UV printing units I see out there. One of these 20w LEDs is plenty coverage for an 8x10, and it can do 11x14 too with a little bit more distance and maybe a couple more minutes printing time. I haven't tried to do larger than 11x14 with it yet.

Similar Threads

  1. Replies: 14
    Last Post: 4-Aug-2017, 17:51
  2. Replies: 15
    Last Post: 15-Sep-2014, 12:14
  3. Replies: 9
    Last Post: 7-Apr-2008, 11:34
  4. fluorescent light
    By tao in forum Style & Technique
    Replies: 6
    Last Post: 30-Apr-2000, 23:50
  5. fluorescent light source for enlarger
    By Colin Seaman in forum Darkroom: Equipment
    Replies: 3
    Last Post: 9-Jul-1999, 15:17

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •