Could you please tell me the distance that the focal calculator has is the distance from the start,the midle or the end of the lens?Its little hard to figure it out.
And is the focus mechanish nesecery?I meen that if the focus is ok,there will be a moment that i will need to change the lens positioning?Or the positioning at that time will be ok 4ever?

I just got the lumenlab packedge and today i orderd the woods .

LUMENLAB I LOVE YOU...xoxxooxooxaooxaoxoix(hope my girlfriend wont see this post or i'm doomed).

The distance is to the approximate center (middle) of the lens.

Once you are focused you never need to refocus unless you move components (screen, projector, or some internal stuff). If you intend to put your projector in one place and never move it or change anything you won't need to refocus.

The distance is to the optical center of the lens, which is usually approximately the center. The difference is minimal, but it's possible for the optical center to not even exist within the lens.

For the pro lenses, the optical center is actually fairly close to the flange. Go figure. For the standard triplet, it's close to the center.

Then i realy need a focusing mechanish...Craps!Anyway i will make it easy for the start and i think i'll find a good way reading the other plogs.

Thank you Durachko and SupraGuy

Do we have a hard number for the pro? Say within a few millimeters? I don't recall seeing one. I imagine it may be derived with OSLO? Be nice to post the actual numbers somewhere.