I'm trying to sort though some ideas I have to make a brightness box for testing and/or adjusting the exposure meters on my used cameras. I'm hoping someone has built a brightness box and if so, could tell me what is needed to do it right? I'm looking for help in adapting what may already be laying around... dimmer switch, house light bulbs, old lamp w/socket, wood to make the box... etc. I only have an old GE light meter, and a DSLR to find light/exposure output from the box and then mark switch positions... Need EV 4 thru 15 if possible, but not sure of what bulb to use... this I can buy if needed. Pointers, links, schematics, anything to help would be appreciated. I tried both apug and google searches, but nothing I found helped. Thanks in advance.