Archived posting to the Leica Users Group, 2004/04/29
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]3 categories 1 - Selenium is the one that doesn't take batteries and wears out. 2 - CdS is inexpensive but eventually get non-linear. Batteries needed. Has a memory when pointed at something bright. Most sensitive type of cell. 3 - SPD (or SBC) is the current technology. Batteries needed. No memory, but it can't measure starlight that well. Quoting Frank Filippone <red735i@earthlink.net>: > Jim, there are 2 categories of meter cells.... the CDS ( cadmium sulfide) > Cells and the silicon photodiode cells. What 's the difference? > > CDS Cells generate their own electricity, and do not need a battery. > However, the cell ( contacts) eventually oxidizes, and when that happens, > the cell loses accuracy and the only way to fix it is to replace the cell. > Examples very familiar to all of us ( old farts) is the Weston Master meters > and some of the Sekonics. One big advantage is that they are very much in > tune with film color sensitivity. More so than the Silicon cell meters. > > Silicon photodiode cells need a battery to work. They are basically > bulletproof from anything other than dropping them. They will last for > years and years before they need any repair. ( Calibration is another > issue... once in a while they do age a bit and need a tweak). Lunasix, and > most of the meters made today are of this variety. The Weston Ranger meter > is also of this type. > > You want reliability and longevity? get a Silicon cell meter that requires > a battery. I saw a few Gossens at the store the other day.... digital > readout and really small... About $125. > > But back to my question... reflected or incident use? > > Frank Filippone > red735i@earthlink.net > > As I understand it, the Sekonics don't need batteries. > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >