I don't understand how 72" wide equals 200" diagonal, especially on a 16:9 screen. My 4:3 at 72" wide is 90" diagonal.
Great results. Wasn't it exciting the first time you got the whole image projected and in focus? I'm curious though, have you managed to get a "perfect rectangular" image - not any sides that are slightly curved? I have't figured out why mine is, yet its not a keystone problem. For all I know, it could be a problem with how my lens is reflecting off a mirror.
Great results. Wasn't it exciting the first time you got the whole image projected and in focus? I'm curious though, have you managed to get a "perfect rectangular" image - not any sides that are slightly curved? I have't figured out why mine is, yet its not a keystone problem. For all I know, it could be a problem with how my lens is reflecting off a mirror.
dont know dude, but i measured it myself and its 198" so work it out if you want, if the edges are slightly curved, it might be that your lcd is not straight, remember that has to be at a 45 degree angle to your mirror, if its 1 degree out, then that one degree will make it bend a bit, so you get 1 bit slightly taller than the other,
thats what i think anyway, cant see it being anything else,
the other thing it could be is the gap from your Frez to your lcd, if that is uneven, that will definatly cause it, cause i had to adjust mine,
thats what i think anyway, cant see it being anything else,
the other thing it could be is the gap from your Frez to your lcd, if that is uneven, that will definatly cause it, cause i had to adjust mine,
Its basically a retrofitted overhead so the arm and everything "should" be straight. I've tried messing with the triplet and mirror without luck. The fresnel was tilted awhile ago but I got that fixed (broken tabs) but nothing changed in the projection. The weird thing I ran into is that the left, top and bottom used to be perfectly straight. Now its the right, top, and bottom. The only thing changed is it moved a few inches one direction (moving it back doesn't fix it) and both the overhead and screen have been risen up nearly a foot. Moving parts of the screen closer/further don't help much (fixes the curve but then the top isn't straight). If you look at http://home.comcast.net/~s.g.s/desktop-on.jpg , you can see what I mean on the left side. The right was slightly tilted in that picture because I didn't put everything back properly after cleaning the optics.
The mirror is what...3x6" or so, just above the lens. LCD is 10.5". Triplet's from diylabs. i messed with it for 10 minutes last night and pushing back on the arm/tilting it upward more corrected the left, right, and top but the bottom was slanted. Plus it was then at such an angle that the top of the image was nearing or on the ceiling (don't remember). Moving the projector a foot each direction just brought horrible keystone into the projection so I figure its about center with the screen how it sits right now. I actually liked it more when the right side was curved and the other 3 were straight...the right side is in the corner furthest away from everything.
At least yours seems to have worked out
At least yours seems to have worked out
SGSeeker said:The mirror is what...3x6" or so, just above the lens. LCD is 10.5". Triplet's from diylabs. i messed with it for 10 minutes last night and pushing back on the arm/tilting it upward more corrected the left, right, and top but the bottom was slanted. Plus it was then at such an angle that the top of the image was nearing or on the ceiling (don't remember). Moving the projector a foot each direction just brought horrible keystone into the projection so I figure its about center with the screen how it sits right now. I actually liked it more when the right side was curved and the other 3 were straight...the right side is in the corner furthest away from everything.
At least yours seems to have worked out
heay SG, your case is of missaligned optics not being in their center position, the frensels focal is out from the light, the top frensel being too far away from the lcd, the mirror has a worp in it, the frensel isnt flat and the projection lens isnt right in the center of the optical axis. Check all of those and get back to me.
Trev
actually, the mirror could be off. Since I don't remember what made the curved edge move to the other side of the screen, yet the only thing I've flipped around is the mirror (had a scratch in a spot so I flipped it so the scratch wouldn't appear in the projection), it may point to that. It appears to be flat but it may not all be perfectly aligned at a 45º angle since all you need to do to keep the mirror in place/take it out is bend two pins. I'll try taking the screws holding the mirror holder out (tough little things) and see if angling the mirror helps/makes it worse.
I believe the bulb is placed in the same place the original bulb was as I reused the reflector in its stock placement and I'm using the stock fresnel. The only way the lens would be off center is if the original lens was as the triplet is mounted within the same hole the singlet was...but since its thicker, it's also closer to the the mirror than I think its supposed to be.
I might try mounting the lens to the bottom of the head instead of inside. This'd allow the mirror to reach a higher angle like I've seen in pictures ( http://www.mbelectronics.com/QuickReferenceGuide/images/apolloAI-1000oh.jpg )...the mirror on mine only goes up to 45º before it hits the edge of the lens. I figured 45º should be how its setup but its possible the rest of the overhead wasn't made for that low of an angle.
The fresnel was warped after I first used it but I managed to get it flat again - didn't fix anything.
I believe the bulb is placed in the same place the original bulb was as I reused the reflector in its stock placement and I'm using the stock fresnel. The only way the lens would be off center is if the original lens was as the triplet is mounted within the same hole the singlet was...but since its thicker, it's also closer to the the mirror than I think its supposed to be.
I might try mounting the lens to the bottom of the head instead of inside. This'd allow the mirror to reach a higher angle like I've seen in pictures ( http://www.mbelectronics.com/QuickReferenceGuide/images/apolloAI-1000oh.jpg )...the mirror on mine only goes up to 45º before it hits the edge of the lens. I figured 45º should be how its setup but its possible the rest of the overhead wasn't made for that low of an angle.
The fresnel was warped after I first used it but I managed to get it flat again - didn't fix anything.
Heya SG, have you got that front surface mirror facing to the lcd with the shinny side down so the coated mirror side is facing the lcd? If not thats the problem, the coated side of the mirror must face the lcd or you will get aberations in your image from the light going through the glass before it hits the mirror surface, the light must hit the mirrored surface first and not the other side with the glass.
Trev
heh, I was gonna say...having a projection the size of nearly my entire wall in this room? Your pixels would be HUGE.
I haven't used my 25" tv since finishing the projector, have you tried it? Looks unbearable now. I don't think you've said if you're projecting onto a wall or screen...which is it? If wall, you really should get or build a screen. Everything looks quite a bit better with one, although its a lot easier to see where your optics are dirty. This can be either a good or bad thing
...and I still haven't bothered messing with the projector. I'm not bored enough to bother with it since the thing still works - it just doesn't look right.
I haven't used my 25" tv since finishing the projector, have you tried it? Looks unbearable now. I don't think you've said if you're projecting onto a wall or screen...which is it? If wall, you really should get or build a screen. Everything looks quite a bit better with one, although its a lot easier to see where your optics are dirty. This can be either a good or bad thing
...and I still haven't bothered messing with the projector. I'm not bored enough to bother with it since the thing still works - it just doesn't look right.
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