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Discussion Starter #1
I have been watching these as the price steady has risen... I wonder if its any of us that are bidding...
http://cgi.ebay.com/aw-cgi/eBayISAPI...tem=1278851747


Interesting things to note... Focal length down to 17ft and 70mm input lens... These are the usual two big issues...


Plus on a purely aesthetic note they look gorgeous !! A quick 'ISCO' search does bring up another one of the same (I think)... Certainly would be a nice gamble if a 17ft throw fits your application...


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I used this exact same lens in my HT. You will experience significant vignetting with your Davis DL450 and clones. Just letting you know...
 

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Isn't it 2X expansion?


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Greg
 

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MC,


Yes.


Cinemascope lenses do a 2x horizontal expansion. Thus, it overstretches the image. To use the enire 4:3 panel of a projector's display with 2.35:1 material, you would need a lens that did either a 1.76x horizontal expansion, or a 44% vertical compression. Of course, any movie that has subtitles that aren't in the picture area will be cut off with a full panel height lens (like this one).
 

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So the conclusion is that it's not worth buying? Even at that price? If you buy a lens like that one I guess you need to use yxy to correct the image! Right?


Bruno

Viewsonic PJL 830
 

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Discussion Starter #6
The reason I had not bought one (I always seem to be pig headed enough to burn my own fingers even when warned) is that I assumed the Davis unit to be the worst for getting the image through that 70mm lens... Many many other PJ's have a smaller beam spot (dramatically) and I was thinking of them mostly... This should avoid vignetting...


Yes they seem to be 2x expansion so YxY is a must...


I would shy away from them at this price though but the other MC2x is still at the $110 mark...


I would like to see how a small beam spot PJ would handle these...


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Yes, you need to use YXY and as Greg points out, you also need to "shrink" the image horizontally, i.e drop resolution, with this lens in place to regain the correct geometry.


PP,

Yes, with a smaller beam spot, you can use this 2x lens. ISCO makes longer focal length prime lenses for various projectors that would allow you to use this with your Davis. These lenses are expensive. Of course, you also lengthen the throw by using a lens with a longer focal length. I think the 1.33x ISCO II is a much better solution, unless you want to just mess around and have fun.
 

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Discussion Starter #8
Larry, I already have a Pannie in hand I just always trawl in case an ISCO I or II is ever being sold by someone who doesn't know its AVS value http://www.avsforum.com/ubb/smile.gif The main reason for looking at these is for the tinkerer's out there that want to get a anamorphic play (I think these should mate with the diminutive LT150 acceptably) at a <$200 price not <$2000 !!


IF I saw another Super Panatar for <200 I would get it just for the variable rate squeeze... I have some hobby robotics experience and a stepper and cog wheel mechanism / actuator tied to Girder serial control to allow variable YxY + variable optical compression would be something to behold... Sure the lens may be a light hog and need cleaning but as a proof of concept for what the 'prefect' lens would be this seems to me to be it...


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Quote:
Originally posted by Phat Phreddy:

IF I saw another Super Panatar for <200 I would get it just for the variable rate squeeze... I have some hobby robotics experience and a stepper and cog wheel mechanism / actuator tied to Girder serial control to allow variable YxY + variable optical compression would be something to behold... Sure the lens may be a light hog and need cleaning but as a proof of concept for what the 'prefect' lens would be this seems to me to be it...

[/b]
You must of missed it but last week, on Ebay, a Super Panatar sold for ~$85 and a Tushinsky-Superscope (an Super Panatar knockoff) sold for $76. I'm the winner of the Superscope. The seller sold me 2 Superscopes for $125. I received them today. The optics in both look to be in pristine condition.




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Greg
 

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Damn! I missed the opportunity of getting such an Isco anomorphic lens...for the Norelco AA2 35/70mm film projector set up. It would be quite a system with one 'em puppies backed by a primary Isco lens. Oh, well...


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Quote:
Yes they seem to be 2x expansion so YxY is a must...
The problem is that now you will loosing horizontal pixels. 2X will give you a 2.76:1 aspect ratio so you will have to horizontally squeeze the image or else crop the top and bottom of the image which is not acceptable IMO.


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