I honestly don't know the answer to that (I recently moved and haven't unpacked that box); I just bought two standard table top goose neck lamps. If the watts end up being too high, you can diffuse the light with toilet paper or tissues. Likely, you won't need to. I think I bought the first/cheapest two I could find on Amazon.
Ok, as far as lighting goes this is what I read: "a hooded lamp with frosted incandescent 75 watt bulb at 12-18 inches under which you can huddle with the coin". I thought I saw in this thread the you wanted flourescent light.
I'm about to score a stereo microscope with a camera adapter on an auction. It's loaded with objective lenses and eyepieces, so mag ranges should be pretty wide. The way it's configured, one eyepiece can be the camera with monocular viewing on the other, or both for viewing to go stereo. Any recommendations for lighting non-transparent things like coins?
Sorry for the confusion. I meant CFL bulbs: the new ones with the spiraling. https://en.m.wikipedia.org/wiki/Compact_fluorescent_lamp
My experience with various stereoscopes is that "modified" ringlighting is the best approach. You'll need a ringlight adapter for the scope, or depending on how it's configured one of the adjustable ringlights with 3-screw mount might work without an adapater. You DON'T want to use the full ringlight for full-coin imaging. The basic rule for coins is that no primary light should come from between 3-9:00. Secondary or "fill" light is OK but needs to be at a lower intensity. You can achieve this type of lighting very effectively using a ringlight with "hard" and "soft" masking. My recommendation as a starting point would be to use duct tape or a couple layers of masking tape to cover the areas between 11:00 and 1:00, and between 3:00 and 9:00. This will give the classic starting point of lights at 2:00 and 10:00, with a 1-hour spread either side. If you need fill lighting from below or the sides, replace some of the duct tape with thinner, more translucent material. Standard white printer paper can work for this. I'd start by opening an area between 5-7:00, and adding a couple layers of paper, then remove the paper until you get the amount of bottom fill light desired.
Thank you for the highly detailed response. Great stuff. Do you like equal light coming from 10 and 2, or one brighter? (Sorry, I'm a former glamour photographer. The 80's were very, very good to me.)
Amount from 10 vs 2 depends on the coin. Usually you want more light hitting the face, so if the bust is facing left, 10 should be a bit brighter. Your experience as a glamor photographer should be very useful for coins. Balancing of shadows and suppressing highlights is key to a really good coin image. It would be a rare thing to shine a light at a model from the floor, so that maps to blocking the ringlight from shining between 3 and 9. Plus I'm sure you have 100 other tricks I know nothing about!
