Archived posting to the Leica Users Group, 2005/02/08
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]http://www.expodisc.com/ In brief, it's a disc that fits the front of the lens to read the color temperature. I haven't tried this tool, but it was recommended by a studio lighting equipment sales rep. It's supposed to be more reliable than white or grey cards for setting white balance because there no hassles with tilting the card and glare and all that. Much cheaper than a color temp meter. Because Expo Discs are individually sized to fit different front threads, one could end up with a batch of them. But, one could get by with only one. As I'll do, because I'm one cheap s.o.b. Here's the strategy; get the disc that fits your largest front diameter lens. In my case, that's 77mm, which means about $149.00 for an Expo Disc that snicks right into place. For smaller front diameter lenses, I'll just hold the disc in place to take readings. So, my 77mm disc will work with 72mm, 58mm, etc., Canon lenses. Of course, when Leica introduces the digital M, I'll have to get the Leica-approved disc to cover 39mm, 55mm and 60mm. For, oh, $995.00. Of course. -Chris Lawson