I have a Sanyo PLC- XM-100 (5000 lumen) projector and I need a shorter throw - anyone have experience with wide angle zoo lenses? Any substantial image degradation ? (Sanyo makes the lens)
Well, Sanyo is no longer, it has now been fully merged into Panasonic. Several Sanyo projector models were slightly modified and added to the Panasonic line under different model numbers but essentially all of the Sanyo projector models are discontinued and limited to what people have in stock. They have kept spare parts inventory for warranty service but I don't know the status on inventory of items like optional lenses, you may just have to see what dealers and suppliers have in stock.
FWIW, Panasonic considers the PT-EX500 as their replacement for the Sanyo PLC-XM100. You might contact Panasonic to see if the lenses for the PT-EX500 would work with your Sanyo. You might also want to look at the Eiki LC-XL100 and Christie LX505, those are OEM versions of the PLC-XM100 that Sanyo made for Eiki and Christie and Panasonic is supposedly continuing production of those for some unknown time, so you could check with Eiki and Christie to see if their lenses might work for you.
As Tony alluded to, there are wider angle zoon lenses but the very widest angle/short throw projector lenses are usually fixed and require that the projector be located on the horizontal and vertical centerline of the projected image. In some cases a shorter throw zoom lenses may also be less flexible in their placement than the standard lens, however I don't think that applies to the shorter zoom for your projector.
Generally, the short throw lenses don't significantly degrade the image. They ay be a bit more susceptible to hot spotting in the center of the image and drop off in the corners. If there are any optical aberrations they also tend to occur in the corners. And you usually want to try to avoid the combination of wide angle lens with a high gain screen.
