View Full Version : Contact printing light source

18-Jun-2013, 04:58
Hi all,

Looking for ideas for light sources for contact printing, which I'm just about to start dabbling with. I'm going to be printing onto Ilford Multigrade RC and I understand that I need a really low wattage light bulb - 15w or less. Problem is I simply can't find that wattage bulb around here. So looking for other light source options until I source something else suitable.



Lachlan 717
18-Jun-2013, 05:26
Bear with me on this one: For low wattage lights, try your local sewing machine shop. Those suckers have small bulbs to light up the area where the "magic" happens.

As for their use for CP, I have no idea.

18-Jun-2013, 05:27
.1 can you find a dimmer?
2. hang the bulb you can find, further away.
3. build a box of some sort around your fixture and cover the open end with a sheet of paper to cut down the intensity.

18-Jun-2013, 06:23
Christmas tree bulb?

Tony Lakin
18-Jun-2013, 07:16
Ed Weston used different sized bulbs suspended from a piece of wooden dowel located in holes at varying heights, if his lowest wattage bulb was too bright he would wrap toilet tissue around it to diffuse and reduce the light output, 'necessity is the mother of invention', experiment!:)

Brian Ellis
18-Jun-2013, 07:30
I'm not sure why you necessarily need such a low wattage bulb. You can control the exposure time by both the wattage of the bulb and also by the distance of the bulb from the paper and negative, at least if you have enough height in your darkroom. It helps a lot if you rig up a pulley system so that the height can be varied depending on the negative. I don't remember the wattage of the bulb I used but I know it was an indoor flood lamp from Home Depot so it almost certainly was brighter than 15 watts.

Jim Noel
18-Jun-2013, 07:53
build a simple electrical circuit which includes a rheostat light switch, and a duplex receptacle. This way you can use any incandescent bulb and limit it's output to the desired level. This will likely cost you $20 or less.
By the way,buy some extra bulbs as incandescents are gradually being removed from the market. Currently it is 100w which ae no longer manufactured, and I believe the same fate awaits 60w at the end of this year.

Merg Ross
18-Jun-2013, 11:02
Since you are not using a slow speed contact paper, strong illumination becomes a problem. How do you plan to use filters with the projection paper? If you have an enlarger, that would be a good light source for contact printing on projection paper; it will give you the opportunity to control illumination and to use filters. Otherwise, as Jim suggests above, a rheostat would be a solution to control illumination intensity.

18-Jun-2013, 12:20
I am dabbling myself and use a 15W bayonet mount bulb from the supermarket in the light fitting. Exposures are about 4-12 seconds. I use the light switch and count. Using Delta 100, x ray and cone methodology 3 digital negatives on ilford multigrade (no filter) so far. Its a fun way to spend time. I am using expired paper bought on trademe relatively inexpensively to use as final support for carbon prints, just repurposed.

Peter Yeti
18-Jun-2013, 14:55
In the old days, photographers used their cameras as enlargers by putting a box with a light source on top of the ground glass. You could try something similar for contact printing and even could use contrast filters in front of the lens like with a usual enlarger. You could adjust the light by the aperture of the lens as well, solving both issues at once.

18-Jun-2013, 18:54
Thanks for the thoughts and ideas. I have been on the look out for 35mm enlarger but at the moment there appears to be few around (for the money I'm willing to spend).

I've got a couple of ideas of something I'm going to try and construct. Will update you on progress!

18-Jun-2013, 20:17
All sorted. My local light shop is making a light for me - a length of cable, with a light socket on one end and a plug on the other, I'll stick some hooks to the bathroom ceiling and I'll rig it up as follows:


What could possibly go wrong?

18-Jun-2013, 23:28
As for low wattage bulbs - I have been shopping only yesterday for a replacement bulb for a glowing globe for our kids - bought a "fridge" bulb - small, standard 14mm thread, 15W. Bought two - one for me and mz contact prints - as I currently use 25W and the times are sometimes too short.

Sal Santamaura
19-Jun-2013, 11:58
...Looking for ideas for light sources for contact printing...I understand that I need a really low wattage light bulb - 15w or less...I'm late to the party since you've already got a plan in place, but decided to reply anyway so future archive searchers will find another alternative. :)

I use this reflector


along with the accessory diffuser


to contact print on enlarging paper. This bulb screws directly into that reflector's socket:


Using Ilfobrom Galerie, my times with properly exposed negatives are in the 20 - 25 second range. Diffusor surface is positioned 20 inches above the print frame. A benefit of contact printing on enlarging paper using low-lumen light sources is that one's eyes don't suffer from whiplash. Alternating between bright exposing lamps and lower-level safelighting with silver chloride contact papers can sometimes result in eyestrain.