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Discussion Starter #21
Well firstly..welcome to the Shack mnfish..

Ideally the prisms for a DIY lens need to be 5" x7"..This size will be suitable for most projectors..

Most commercial lenses these days are using 4 prisms plus corrective elements..
These types of lens units are beyond a DIY set up..but the 2 prism lenses do a fine job and well worth the effort..:T
 

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Thanx for the Hello!!

The reason I ask about the number prisms is that 4 of them seem to do away with the rainbow affect on the outer edge of the screen? Or would it be better to have a curved screen? Is that just too much to get into for a simple home theater screen? And looking at cost of the prisms...they aren't that cheap? The ones I was looking at were $66 US each.
 

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Discussion Starter #23
A curved screen won't have effect on any Chromatic Aberrations that you see at the sides of a screen.
Curving the screen helps to reduce pin cushion effect..

You need to use the best quality prisms you can find, so there is a premium to pay..
 

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Discussion Starter #25
I know of many people who have Marks new Mk.3 lens..In Aus, UK and the US and ALL are very impressed with the quality of the build and the image it produces..
It's right up there with the best of any 4 element prismatic lens..and very reasonably priced..:T
 

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I've not posted in a while and thought some might like to see the latest developments.

The CAVX Corrector


And of course the best of the best, the MK4.

It is pretty impressive when you can see pixel structure on an AT screen.

It seems I can not attach images, so here is the link to the image I am referring to. Click on the with the word "FOCUS" in the centre. If you look closely, you can see fine lines in both the Horizontal and Vertical lines of the Test Pattern. They are the interpixel gaps of a 1080 DLP.
 

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Discussion Starter #27
Quite remarkable Mark..:clap: :T
You certainly have come a long way with the advent of the Mk.1V!
How are sales going?..It seems that there just isn't the interest in anamorphic projection these days..
I've also noticed that there's not a lot of A lens activity on the AVS forum these days either..

I think a lot of people who had considered going anamorphic, are now looking more at the preset AR projectors, as a cheaper alternative..

Good luck with the new lens..
 

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There is plenty of interest, just not too many people prepared to pay the price for a high quality lens.
 

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Discussion Starter #32
Hi Prof i cant find the build specs for the housing (BOX) only where to get the prisms in AU. Cheers
I don't think any specs for the housing was published..
It will of course depend on the size of the prisms..
If the prisms you refer to are the ones used in Marks earlier models, then I can pass on the dimensions of my housing to you..
 

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Discussion Starter #37
You only need to blackout the thick end of the prisms..

My original prism ends were blacked out with flock tape, but the backing on the tape actually reflected the image!
If you looked at the lens from the side, you could see a reflection of the image!!

I removed the flock tape and painted the ends with a special matt black glass paint..and I would recommend that you use a similar product..
It's a 2 pack application..consisting of a glass primer and a carbon black fluid acrylic..
This product is available from Artists supplies..The brand I found was Jo Sonja's..which I bought online..
 

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ok will be building my Anamorphic lens this long week end. I will be making a new screen but should i go 2:35 0r 2:37 screen? cheers Troy
 
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