Interest in 22" EFL w/ 5" Diameter Opaque PJ lens?

[Guy Grotke]

eBay auction #7569996997

This is a Beseler.

[Lwilliams]

Guy,
Thanks for the heads-up on the Beseler 22in efl lens. I ordered one from Ludek(AAAequipment@aol.com), and it arrived today.
I have been planning and gathering parts for some time now, and this was just what I was looking for.

My Projector components:

Samsung 710T 17 ''
1280 x 1024 (selectable to 1280X720 for 15" widescreen)
Contrast ratio 600:1
Average response time 12 ms
IceCap 400MH 400w ballast (www.diyprojectorcompany.com)
OSRAM HQI-TS 400W Daylight – HM (www.exclusiv-online.com)
12.000 h
5200 K color temperature
Color index: 93
Glass reflector (cold mirror) (www.exclusiv-online.com)
50 mm Diameter
IR/UV glass filter (www.exclusiv-online.com)
Diameter 90 mm x 2 mm thick
Fresnel Lens 220mm fl (www.diyprojectorcompany.com)
Fresnel Lens 550mm fl (www.3dlens.com)

I picked up a couple of 128mm Dia. x 1000mm Fl coated Positive Meniscus lenses from Anchor Optical Surplus for $12.00 each. I had planned to use these spaced about 120mm apart as my projection doublet, but this lens sounded too good to pass up!

Hope to get everything setup and tested in the next week so I start designing the cabinet.

Lloyd

[Guy Grotke]

It will be interesting to see just how well it works with a 17" LCD. If the corners seem too dim, I do have a suggestion for an experiment:

You could probably increase the FOV of this lens by remounting the lens elements in another tube (maybe a 4" ABS pipe coupling?), with the lens elements a bit closer together. That is what some people have done with 18" EFL triplets, and they claimed they got wider FOV with only a tiny loss of sharpness in the center of the image. I think you could try this without damaging the original tube or lenses, so you could put it back together afterward if it didn't work out.

Anyway, please post your results when you get it all together. From your parts list, it sounds like you will have a great projector.

Try it with the DIY doublet too. That would be another very interesting "data point".

[graffixjones]

Originally posted by Guy Grotke
eBay auction #7569996997

This is a Beseler.

Just wanted to say thanks Guy for pointing a bunch of people at the auction I was bidding on (didn't even know this post existed)...

Oh well... can't win them all I guess

I actually found this post as I'm searching Google trying to find another Beseler for my 17" projector... since the first one got sniped away...

[Guy Grotke]

If it got sniped, then you just weren't willing to pay what it was worth!

Seriously though, anybody should be able to find an opaque projector lens, or maybe a whole projector for the lens. In this case, the winning bid was $71, which is right about the winning bid level I have seen for several of these lenses. (The 22" fl lenses that started this thread were $75.)

If sellers see a steady market for these lenses, then they will bother to list them. If they see them going for $12, then they will not list them. I think it's better to have the market exist!

If you really need one immediately, then I would try bidding about $85 in the last 30 seconds of the auction just to make sure I won it. If you have to get a bargain to feel good about it, then you can try for a low-ball bid. I have seen one go for $12!

[supahcool]

I´m a lucky guy , I won 2 ebay auctions months ago , 1 opaque projector that I asked seller to send me only the lens , and 1 american optical 18" efl lens. paid only about $35 for each one. the first one did a typo on description (besler). when I won the first I was a zero FB international ebay user !!!

[Quinn]

does the front, middle, or back of the lens have to be the field fresnel FL away?


im trying to plan if a long throw modification is possible

also how good is the focus on an 18" FL beseler

[ukagr]

Hey Guy, What would happen if i used a 330mm frensel with the 18" EFL instead of the 550 that you were using?

And i got my 18" lens for free at a surplus auction. I asked the guy how much he wanted for it , he said he didn't want it so he gave me the whole projector!

[superdaveumo]

If you use a smaller LCD, 330mm fresnel would be fine.

[superdaveumo]

I have an 18" opaque projection lens on a 17" projector. The focus is great until you hit the corners (on a 17" LCD). They start to become blurry right around the Start button (windows) and the same blur in the other corners.

With a smaller LCD (15" and smaller), I would suspect that the focus would be no problem. It's all about FOV. Search FOV (field of view) for some answers.