DIY anamorphic lens

[Mark Techer]

Hi Bud, the light reflections I got were more like those seen from Steve back (link here ) when he was first trying to stretch 4 x 3 to Scope. You can see the "rainbow" on the side of his image - too much stretch? - and I got similar results but in the centre, so worse than his.

I cannot explain why the reflections are there except to say that maybe the light between the faces of the pairs is the problem as the coating does not totally remove the stray light, but reduces it.

The results of a 4 Vs a 2 prisms lens is not trivial so far as a reduction in CA is concerned, but there was too much stray light for me to work with, much less market.

When I have the prisms bonded, I will conduct further testing...

Mark

[Mark Techer]

The prisms are bonded and I will test tomorrow...

Mark

[Mark Techer]

Tested the new bonded prisms today. For the effort that is required Vs the end result, I don't think it was quite worth it. Sure there was some benefits (CA was slightly less for sure) but I could not see this being economically viable long term...

Mark

[satguy]

so what company are people using for the antireflective coating?

[Mark Techer]

In the US they are using LL, but I ordered my prisms with an anti-reflective coating...

Mark

[ROTTEN ROD]

Hey Roar,
I am just finishing my basement with a HT room. I have abandoned my old house/HT set up to start anew. Only gear i am bringing across is my speakers. I want to make a hd projector purchase soon, before November, and will ensure it has V stretch (looking at Optoma HD81-LV as Optoma offers their own Anamorphic lens I am making an assumption it does). Think I will need a set of the prisms. Where in Ontario can I find them. I live in Brampton.
Any help appreciated.
Biting at the bit to get started. Will be going Blu-ray for sure... hope that is not a hinderance to working out CIH...

Rotten Rod. (sorry would have e-mailed but i am new to DIY)

ps. this thread is like a train wreck, have been unable to look away.

[Mark Techer]

It has been documented from the beginning of this extremely long thread that we should be using prisms with a different Refractive Index.

Whilst researching the topic, I found a link that showed a lens element made from two different materials bonded together - flint and corning.

Given that most of use are using optic glass for both prisms, does anyone think that some improvement could be made by bonding another type glass to the prisms face?

Mark

[roar]

Originally posted by ROTTEN ROD
Hey Roar,
I am just finishing my basement with a HT room. I have abandoned my old house/HT set up to start anew. Only gear i am bringing across is my speakers. I want to make a hd projector purchase soon, before November, and will ensure it has V stretch (looking at Optoma HD81-LV as Optoma offers their own Anamorphic lens I am making an assumption it does). Think I will need a set of the prisms. Where in Ontario can I find them. I live in Brampton.
Any help appreciated.
Biting at the bit to get started. Will be going Blu-ray for sure... hope that is not a hinderance to working out CIH...

Rotten Rod. (sorry would have e-mailed but i am new to DIY)

ps. this thread is like a train wreck, have been unable to look away.

I'll have to see if I can dig up that list that I had with the local vendors... that was a long time ago I'll send it your way if I can find it...

In the mean time I may have 2 prisms for sale, I bought 4 originally and I am only going to use 2 I think, not sure yet, have to do some more 4 prism testing first, so that may be an option for you as well...

When considering your projector make sure you look into whether it does the stretch over HDMI, if you are going Blu Ray, I'm guessing you are going to want to run HDMI. I was originally looking at the Optoma HD70 because it does the stretch but my research lead me to believe it does not do the stretch over HDMI, only Component, I ended up puchasing the Panny AX100u insteadto go with my Toshiba A20, I will be using that player to upconvert my SD DVD's over HDMI.

[Mark Techer]

Roar, if your going to get any improvement from 4 prisms, you need to bond them. Not the easiest thing if you want perfect bubble lamination, but other wise you just get more stray light reflections - even with coated prisms...

Mark

[roar]

Originally posted by Mark Techer
Roar, if your going to get any improvement from 4 prisms, you need to bond them. Not the easiest thing if you want perfect bubble lamination, but other wise you just get more stray light reflections - even with coated prisms...

Mark

I don't see any bonding in my future

I remember doing the 2 and 4 prism tests at Bud's last year and seeing very little difference, I'm not expecting much at all and I'm guessing I will have 2 available quite soon