I have done a lot of research (including searching these forums) but have been unsuccessful in finding an answer to:
I have a fixed throw distance (Approx 4 meters) and am wanting to use a 15" lcd monitor for the projection source.
The only place I can find lenes available in australia is lumenlab, and they only offer 1 set of focal length lenses which are:
1 * 220mm focal length fresnel
1 * 317 mm focal length fresnel
1 * lens triplet Focal length: 320mm
Now the issue is that I only want a screen size of 2.5 meters (diag), by my calculations the projection will be about 4 meters given that lens combination.
What can be done? Are there any tricks for shrinking the screen size in this situation?
Obviously the correct solution to the problem is to find a supplier for the correct fresnels and tripplet for my throw distance, but my searching has not proved successful.
Anyone know a supplier that can supply matched fresnels and triplet lens to give my what I need?
Many thanks in advance, and sorry if I'm asking questions which have already been answered.
Cheers,
--segfault--
I have a fixed throw distance (Approx 4 meters) and am wanting to use a 15" lcd monitor for the projection source.
The only place I can find lenes available in australia is lumenlab, and they only offer 1 set of focal length lenses which are:
1 * 220mm focal length fresnel
1 * 317 mm focal length fresnel
1 * lens triplet Focal length: 320mm
Now the issue is that I only want a screen size of 2.5 meters (diag), by my calculations the projection will be about 4 meters given that lens combination.
What can be done? Are there any tricks for shrinking the screen size in this situation?
Obviously the correct solution to the problem is to find a supplier for the correct fresnels and tripplet for my throw distance, but my searching has not proved successful.
Anyone know a supplier that can supply matched fresnels and triplet lens to give my what I need?
Many thanks in advance, and sorry if I'm asking questions which have already been answered.
Cheers,
--segfault--
Look up some of Guy Grotke's posts regarding a homemade long-throw duplet made from eyeglass blanks. I'm still not sure where he got his matching long-throw fresnels for that. It's hard to find a set of matching optics for this application.
Probably the easiest solution is to use a smaller LCD. Again, hard to find. But there's a better chance this way, especially if you are willing to give up some resolution. A reflector and condenser are also a good idea since the small LCD will capture less angle of the light sphere emanating from the light source.
See, here's an 8" display. 800x600. That would get you right down to the image size you're looking for. The image would be almost half the size (quarter the area) of a 15" projector at the same throw distance. Shipping on this particular item is murder, but at least the options are out there. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5220221772&category=3698&rd=1
Probably the easiest solution is to use a smaller LCD. Again, hard to find. But there's a better chance this way, especially if you are willing to give up some resolution. A reflector and condenser are also a good idea since the small LCD will capture less angle of the light sphere emanating from the light source.
See, here's an 8" display. 800x600. That would get you right down to the image size you're looking for. The image would be almost half the size (quarter the area) of a 15" projector at the same throw distance. Shipping on this particular item is murder, but at least the options are out there. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5220221772&category=3698&rd=1
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.