enlarger conversion cont.greenspun.com : LUSENET : Large format photography : One Thread
Another question regarding my attempt to convert a copy camera into an enlarger (8x10 plus). Several days ago I mentioned that I picked up a Goodwin copy camera with a 13'' x 15'' opening at the top of the bellows. Well today I picked up some kind of light box at a metal recycler. I thought I might try and use it as a light source. At first glance, it looked like a light box for viewing negs/trans. , but on closer inspection, I'm not sure. Firstly, the odd thing I noticed is the bulb. It looks to be neon, and is white. It's quite a sophisticated looking bulb. The bulb zig zags, much like Ansel Adams used for a cold light source, although no where near the same concentration of tubes. The total area the tubes cover is 14'' x 18''. I've never heard of neon being used as a light source for a light box. I'm wondering what colour temperature it has. An electrician I showed the box to, expects the light would be quite powerful judging from the guage of power cord. That is the second problem, the plug on the power cord. It's not North American or anything European. It could be a special plug that plugs into a transformer/power source. It's square with five prongs. Four of the prongs are flat (like the North American plug), with a round prong in the middle. Two electricians couldn't identify the plug. I'm not sure if the box has a seperate power source or not, it's quite heavy. Lastly, the box has two pieces of glass, but no white plexi for diffusion. The bottom piece of glass is attached to the box, but the second piece is hinged and they sandwhich together. It would be a perfect place for filters or maybe even your neg?
Any comments or help would be appreciative, thanks
-- Colin Seaman (email@example.com), April 23, 1999
Colin...I admire your pluck. Beware that your new 'light box' dosen't take off when you fire it up.
-- C Matter (firstname.lastname@example.org), April 23, 1999.
To follow up from earlier today, I took the light box to a neon sign maker. He cut the plug off and hooked the wires up to a transformer, and voila, it worked great. Apparently the neon light source could be used at two power levels to give the user some control. The technician also told me that he could add more tubes and a bigger transformer if I needed more power, and I'm sure I do. Does anyone out there know how many watts (or fstop) I need from a cold light source like this, to enlarge an 8x10 negative? Assuming I'm using a 300mm process lense and have about 26'' of bellows. I know the Aristo light sources vary from 400 watts and up, but I've also seen adds for Durst enlargers with 2000 watt tungsten halogen light sources.
-- Colin Seaman (email@example.com), April 23, 1999.