Hey Guys,
I got everything on my build done except drilling the hole for my triplet. I am hesitating on this because I don't know where to drill it. How do I know where to position it? I don't want to make it to high or too low, or too much to the side. The Horizontal position I don't think is too much of a problem since I am using a FS mirror to direct the light into the triplet.
Anyways how do I determine where to place the triplet? It seems like a chicken and the egg thing. I need the optics working to adjust them, but I can't get the optics working until I drill the hole. How do I know where to put the hole for the triplet, since once the wood is drilled, I can't really fix it.
Any help is appreciated.
Thanks
Christof
I used a temporary focus board/box to mount mine on, until I could get the optics lined up properly.
I then took the board which I was going to use as the final lens board, put it in place, and with the top off the projector (the light box area covered) I moved the board forward and backward until I got a fairly sharp arc image, marked that (basically drew an outline of the arc image), and then marked the center of that so that the arc image would be centered in the triplet. Once I found the center, I cut the hole, mounted the lens, mounted the lens board, and it's perfect.
I then took the board which I was going to use as the final lens board, put it in place, and with the top off the projector (the light box area covered) I moved the board forward and backward until I got a fairly sharp arc image, marked that (basically drew an outline of the arc image), and then marked the center of that so that the arc image would be centered in the triplet. Once I found the center, I cut the hole, mounted the lens, mounted the lens board, and it's perfect.
QUOTE (fmerrill @ Oct 1 2007, 12:53 AM) 
I used a temporary focus board/box to mount mine on, until I could get the optics lined up properly.
I then took the board which I was going to use as the final lens board, put it in place, and with the top off the projector (the light box area covered) I moved the board forward and backward until I got a fairly sharp arc image, marked that (basically drew an outline of the arc image), and then marked the center of that so that the arc image would be centered in the triplet. Once I found the center, I cut the hole, mounted the lens, mounted the lens board, and it's perfect.
I then took the board which I was going to use as the final lens board, put it in place, and with the top off the projector (the light box area covered) I moved the board forward and backward until I got a fairly sharp arc image, marked that (basically drew an outline of the arc image), and then marked the center of that so that the arc image would be centered in the triplet. Once I found the center, I cut the hole, mounted the lens, mounted the lens board, and it's perfect.
What do you mean by arc image? How would I draw it?
I suppose I could unscrew the triplet board and use a piece of Cardboard or something in place. I kinda lost you after that part.
He's saying just use your lamp and fresnels as your guide. Turn on the lamp and as the light passes through the fresnels you will see the arc begin to form on the inner front of the board where your triplet will be (best to sunglasses when doing this I suppose). As the arc gets brighter you then start marking the edges of the arc onto the board with a marker. Might be best to remove the lcd if you have it in place, it will get brighter. After marking the area of arc on the front board - remove it and find the bull’s-eye center of your markings, thereafter, you then mark the circumference of the triplet in that area. Before cutting, it might be best to remeasure. By this time you will have found out if your optics are lined up and centered within your box.
Arc image
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