I dont even know if it's considered a triplet. I got it off an old video only LCD projector, it has a mechanical focus but the projector itself is broken so I dont think that'll work too well. I can kind of twist it anyway. Text printed on the lens says "LCD Projector Zoom Lens 100-160mm 1:3.9-5.2". Also, what fresnel lenses do you guys reccomend to buy for a 17 inch projector? I want to try and avoid dark corners if at all possible. Pro lenses are on backorder and I have until december 7th to build my projector, so thats a no-go. Also please tell me if I will have to cut the fresnel to size. Here are some pics of my triplet (or whatever it is):

Heres another pic of the lens:

100-160mm is pretty short focal length you would have to place the projector very close to the screen. I'm assuming that the LCD used in the projector was something like 1" so the FOV (field of view) will probbaly be very small. This probably won't work i.e. it won't be able to "see" a 17" LCD. The standard triplet will work with a 17" so if you can't wait for the PRO use the standard and maybe upgrade later.

alright thanks for the info

what do you guys reccomend as far as fresnels are concerned?

220/330

The LL store fresnels will be too small, so I'd go for the 220/330 focal length 395mm x 395mm's from 3dlens.com . I'm planning on using them in my 17" LCD projector as well.