Ok, thats the kind of answer i needed 🙂 .. ya, the fresnels were offset a bit from eachother so im hoping thats it..... And i hope the colours even out a bit too .
But there is also the problem with the light . Shouldnt it be a rectangle pretty much, not a circle on that screen. But the lcd wasnt in its frame and the screen was only 3 feet away, about, instead of 8feet like its supposed to be. Will those have to do with it?
But there is also the problem with the light . Shouldnt it be a rectangle pretty much, not a circle on that screen. But the lcd wasnt in its frame and the screen was only 3 feet away, about, instead of 8feet like its supposed to be. Will those have to do with it?
yes
Use the real throw distance you plan to use. If it is focussed at 8' and the screen is only 3' away, then you will see a big round blob.
Using the real throw distance is important so you can get the right LCD-to-lens distance. With that, you can adjust your lamp and fresnel positions until you are getting nice even light mostly into the lens. If you set it all up with one throw distance, and then change that radically, it will need more adjustment.
Use the real throw distance you plan to use. If it is focussed at 8' and the screen is only 3' away, then you will see a big round blob.
Using the real throw distance is important so you can get the right LCD-to-lens distance. With that, you can adjust your lamp and fresnel positions until you are getting nice even light mostly into the lens. If you set it all up with one throw distance, and then change that radically, it will need more adjustment.
Ok, i did all that, set it up at 8feet. Its alot better, but the sides are still dim and a little orange looking but its not green no more but a tiny bit bit on the edges. But i ran it for 40 minutes or so while testing it so that slowly helped, hope it gets better.
I tried the whole setting it all up and then removing the lcd and pj lens and then focusing the arc image on a piece of papr where the pj lens should go. I moved the lamp closer and it gets WAY more focussed and the light distribution was sooo much better. I got it from this site: http://www.diyaudio.com/forums/showthread/t-68683.html
I Put the lens and lcd back in and the edges were fine so i guess thats what my problem was. But the wierd thing is is that the lamp is almost 1 inch closer to the first fresnel which made it about 190mm instead of 220mm. Should it be that far off or is that normal.
I tried the whole setting it all up and then removing the lcd and pj lens and then focusing the arc image on a piece of papr where the pj lens should go. I moved the lamp closer and it gets WAY more focussed and the light distribution was sooo much better. I got it from this site: http://www.diyaudio.com/forums/showthread/t-68683.html
I Put the lens and lcd back in and the edges were fine so i guess thats what my problem was. But the wierd thing is is that the lamp is almost 1 inch closer to the first fresnel which made it about 190mm instead of 220mm. Should it be that far off or is that normal.
whatever it takes
If moving the lamp to that position gave you a nice sharp arc image right where the center of the lens goes, then that is what you want. Your lamp arc distance is compensating for the imperfect match between the field fresnel focal length and the distance from the field fresnel to the center of the projection lens. If it was way far off, then I would suggest you look for a field fresnel that is a better match, but in your case I think its fine.
That is exactly what you needed to do to tune the condensor system. Congrats!
If moving the lamp to that position gave you a nice sharp arc image right where the center of the lens goes, then that is what you want. Your lamp arc distance is compensating for the imperfect match between the field fresnel focal length and the distance from the field fresnel to the center of the projection lens. If it was way far off, then I would suggest you look for a field fresnel that is a better match, but in your case I think its fine.
That is exactly what you needed to do to tune the condensor system. Congrats!
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