protecting light leak on an ohp
I wish I could find the software for my digital camera, I'd take some pictures of my OHP and how I have it set up... I'll try to describe it as best as I can.
My father in law rounded up an old 3M 66AG OHP for me a couple weeks back... I was using it just to play with for a while until I got my first panel... I was able to get some decent focus with it, but found that I just couldn't get the lens in the right place... mostly because the mast just wasn't in the right place. So I yanked the mast off of the OHP... I also decided to use a different lens... I have a barrel lens (beseler 12.5EF series III from an opaque projector I think) So I got creative.
For almost all the "construction" I used a couple of sheets of that pressed board stuff that comes with boxed furniture (computer desks, dressers, entertainment centers)... I had a piece from an old entertainment center that I had torn down, and I kept those panels cuz I figured they may come in useful someday... they sure did... easy to cut with a razor blade, sturdier than cardboard, and it looks a little better.
First thing I did was took a big chunk of it that had a natural crease in it to fold it up, and cut it to the right size to make a screen (not a projection screen, think more like the kind that sexy women get naked behind in the movies
) that I can put in front of my OHP. Tall enough to block a LOT of ambient light, short enough not to hinder the projection. I have the ohp on a little stand about 2' tall, and my "screen" sits on the floor, so ther is about 6 inches between it and the front of the OHP... plenty of room for circulation.
Next I stripped the first surface mirror out of the mast from the OHP and using my new favorite construction material, I fashioned a little box with four sides: left, right, back, and top. I drilled a hole on the front edge of the left and right sides and ran the bolt that held the mirror in the mast head through those holes... This way, the mirror swings freely in my little box, and by placing it over my barrel lens, I can slide it forward and backward against the barrel to get it to reflect at the angle I want. I can also turn it side to side for lots of positioning options.
To replace the mast itself, I fashioned 2 big squares out of 2x4 scraps I had. They are about 21" tall and 10" wide. I placed one on each side of the ohp. For some sturdiness, I used a couple strips of that same pressboard stuff across the back, just like it's meant to be used to make an entertainment center sturdy. Wonderful side benefit is that it also blocks out a lot of ambient light that escapes through the rear. It's only from the top of my 2x4 frame to the top of the OHP, I didn't go down far enough to cover my fan vent.
To mount my lens to this whole crazy thing, I took a piece of scrap sheetrock (easier to work with than wood, but more rigid than the pressboard) and I cut a large hole in it.. The other half of my barrel lens (which is duct taped to a scrap of 1x8) hangs down through the hole, and the 1x8 that the lens is on sits on the sheetrock. The sheetrock then spans across the two 2x4 frames.
For focus, I drilled a couple large holes in the top edges of the 2x4 frames about 3/4" deep and went to home depot and bought 4 6" 3/8 bolts threaded the entire length, and 4 3/8 T nuts - cost: ~$3. I put the T-nuts into the bottom of the sheetrock, and threaded the bolts down through them... Then the bottom of the bolts go into the holes in the top of the wood frame. By manually turning each of the 4 bolts, I can focus the lens quite well.
I think you'd be amazed at the amount of light leak I've managed to kill off, without even really doing anything to the normal circulation of the OHP.
That's it... Now after that, I'm sure I'll get lots of people wanting to see this crazy thing... and I'll admit it looks pretty goofy, but for what I've got into it, I've had a lot of fun playing with it, and I'd post my results if I could get my camera to work... maybe I can do something with my cam corder... it just takes so long to get them moved to the computer.
I wish I could find the software for my digital camera, I'd take some pictures of my OHP and how I have it set up... I'll try to describe it as best as I can.
My father in law rounded up an old 3M 66AG OHP for me a couple weeks back... I was using it just to play with for a while until I got my first panel... I was able to get some decent focus with it, but found that I just couldn't get the lens in the right place... mostly because the mast just wasn't in the right place. So I yanked the mast off of the OHP... I also decided to use a different lens... I have a barrel lens (beseler 12.5EF series III from an opaque projector I think) So I got creative.
For almost all the "construction" I used a couple of sheets of that pressed board stuff that comes with boxed furniture (computer desks, dressers, entertainment centers)... I had a piece from an old entertainment center that I had torn down, and I kept those panels cuz I figured they may come in useful someday... they sure did... easy to cut with a razor blade, sturdier than cardboard, and it looks a little better.
First thing I did was took a big chunk of it that had a natural crease in it to fold it up, and cut it to the right size to make a screen (not a projection screen, think more like the kind that sexy women get naked behind in the movies
) that I can put in front of my OHP. Tall enough to block a LOT of ambient light, short enough not to hinder the projection. I have the ohp on a little stand about 2' tall, and my "screen" sits on the floor, so ther is about 6 inches between it and the front of the OHP... plenty of room for circulation.Next I stripped the first surface mirror out of the mast from the OHP and using my new favorite construction material, I fashioned a little box with four sides: left, right, back, and top. I drilled a hole on the front edge of the left and right sides and ran the bolt that held the mirror in the mast head through those holes... This way, the mirror swings freely in my little box, and by placing it over my barrel lens, I can slide it forward and backward against the barrel to get it to reflect at the angle I want. I can also turn it side to side for lots of positioning options.
To replace the mast itself, I fashioned 2 big squares out of 2x4 scraps I had. They are about 21" tall and 10" wide. I placed one on each side of the ohp. For some sturdiness, I used a couple strips of that same pressboard stuff across the back, just like it's meant to be used to make an entertainment center sturdy. Wonderful side benefit is that it also blocks out a lot of ambient light that escapes through the rear. It's only from the top of my 2x4 frame to the top of the OHP, I didn't go down far enough to cover my fan vent.
To mount my lens to this whole crazy thing, I took a piece of scrap sheetrock (easier to work with than wood, but more rigid than the pressboard) and I cut a large hole in it.. The other half of my barrel lens (which is duct taped to a scrap of 1x8) hangs down through the hole, and the 1x8 that the lens is on sits on the sheetrock. The sheetrock then spans across the two 2x4 frames.
For focus, I drilled a couple large holes in the top edges of the 2x4 frames about 3/4" deep and went to home depot and bought 4 6" 3/8 bolts threaded the entire length, and 4 3/8 T nuts - cost: ~$3. I put the T-nuts into the bottom of the sheetrock, and threaded the bolts down through them... Then the bottom of the bolts go into the holes in the top of the wood frame. By manually turning each of the 4 bolts, I can focus the lens quite well.
I think you'd be amazed at the amount of light leak I've managed to kill off, without even really doing anything to the normal circulation of the OHP.
That's it... Now after that, I'm sure I'll get lots of people wanting to see this crazy thing... and I'll admit it looks pretty goofy, but for what I've got into it, I've had a lot of fun playing with it, and I'd post my results if I could get my camera to work... maybe I can do something with my cam corder... it just takes so long to get them moved to the computer.
Personally If I was you Id just stay with the LCd panel for now, Its allready at your disposal and there isnt a problem with maybe skrewing up a LCd monitor, The panel will be worth just as much in 2 months or so, and By then you will have a better Idea of what your wants and expectations are and Maybe LCD monitor prices will go down a little more for Christmas shoppers.
🙄
🙄XBOX and projectors
I too had dim scenes with the XBOX and my DIY setup.
(Elmo SD 575w MH, NEC1545v).
The rez was fine using a 9a62 component-VGA adapter, but everything was kindof muddy.
since I upgraded to a X1 DLP projector, it is alot better....but still not as clear & bright as on my 50" RPTV HDTV monitor. I'm still using the 9a62 converter.....next I will get the proper cable to run component video directly into the X1 and see what happens.
Anyone out there have the answer to the muddy XBOX image problem????
I too had dim scenes with the XBOX and my DIY setup.
(Elmo SD 575w MH, NEC1545v).
The rez was fine using a 9a62 component-VGA adapter, but everything was kindof muddy.
since I upgraded to a X1 DLP projector, it is alot better....but still not as clear & bright as on my 50" RPTV HDTV monitor. I'm still using the 9a62 converter.....next I will get the proper cable to run component video directly into the X1 and see what happens.
Anyone out there have the answer to the muddy XBOX image problem????
I made a Xbox vga cable and my Xbox image improved greatly. I had more contrast, brighter, and sharper picture. This was on a commercial infocus projector but I would think it would help diy setups too. Only problems are you have to have a mod chip for the vga bios and some game don’t work. I have never tried this one X2VGA (this is not a line doubler this is a hdtv to vga trascoder. Much better picture) but people on xboxhacker.net were saying that it gave them a very bight clear picture. Only problem with this one is it only works with hdtv compatible games but the good thing is you do not have to have a mod chip.
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