First a question for Lucky_Me..I just read some parts of the 33pager on your parabola experiments...the question what happened to your parabola reflector projector ?

Aiden was also working on one...

Am I wrong but with the short arc lower wattage lamps that are available perhaps the parabolas are positively feasible again....lower wattage lamp...smaller arc size.

Another..once was talk of using off-axis reflectors..did any one try this ?

Has anyone toyed with 2 reflectors/2 lamps (side by side)

arizonavideo has done some work in this area. Check out his "The Frankenfresnel" thread.

There was also a guy saying that you could get very good results by using 2 eliptical reflectors placed end to end with a small hole in one end. The guy was here for a while (couple weeks maybe), then kinda fizzled away. Lemme find his plog...
Here it is: "Me2!'s Bag Of Tricks".

Hi Hirudin

Yeah I know AV has done some interesting stuff with 2 Fresnels but I was more thinking
2 parabolic reflectors & 2 lamps.

Just not sure what happened in the end with Lucky_Me's Aidens experiments...

Pinging Lucky_Me

I guess that means you want a reply.

I just somewhat ran out of time with the Parabolic Projector, then afterwards... I lost interest. I guess I could finish it, but really I don't have the will to. I know people here would have liked to have seen some sort of projector built from it. I don't know what happened to Aiden's idea.

Marco_Polo recently gave me a good reason to drop the Parabolic design. If you've read the thread you will see the part where I could start a fire with the Parabolic Reflector and one USHIO S400DD lamp. He told me imagine passing all that energy through my expensive WUXGA panel. That kind of killed any further aspiration on my part.

Why not try CDM lamps? I don't know... someone here was suppose to ship their unused Parabolic Reflector. I haven't recieved it yet, hint hint. You know who you are. Anyways, if I was to try a CDM lamp I would need a new reflector as mine is modified for the S400DD (which I have now sold).

Lucky_Me

Thanks for your reply...

This DIY thing can be expensive not so much the buying but of the time/effort spent...therefore I can understand why you never completed the PJ...hell Im one of those who are yet to commit to start a build !!

I seem to think alot/talk a lot..I keep promising myself that I will get it on ..soon..always seem to be looking at ideas instead of building.

The last time Aiden was active was back in May 2006..so I guess we probably wont hear from Aiden.....pinging AIDEN !!!

BTW I hope u dont mind me asking if you ever got 'even illumination' with the parabolic?

Cheers

I did, but I had to have a great distance between the Parabolic Reflector and the LCD. Something like 24". Now, a person would have to have stripped his LCD and actually built a projector to know if there was going to be problems.

FWIW once again I refer to the diyaudio forum....a guy was trying to get a parabolic reflector designed to fit a 15.4 inch LCD...

he mentions that the parabola has to be deep enough so that the focal point is well inside the parabola..the idea being to catch as many rays as possible from the source...

Yes and no he didnt succeed at least yet i getting a design...he was hoping somebody could help, Im not sure there would be many with the knowhow to work this out... a good shape, which would be sorta parabola then into rectangle...

His best bet is to just buy the Edmunds 18" Parabolic Reflector, cut it to size and then place it 24+" away from the LCD. Then line the inside of the light engine with mirror, that's what I was planning on doing.

This is the only place I know of that sells large parabolics. They might be available thru 18Wheeler/ywh.
http://www.hb-optical.com/English/reflectors/parafl.htm