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I've Joined The A-Lens Club! - Page 2

post #31 of 46
Thread Starter 
Quote:
Originally Posted by RapalloAV View Post

Looks like you may have finally seen the light Rich!

Thanks.

I'm not sure I've experienced any new revelation. I've planned on the possibility of acquiring an A-lens from the beginning and have inquired about them for years here, while exclaiming all the A-lens set ups I've seen looked wonderful.

As I said, this mostly has to do with the practicalities of my limited throw distance. It does introduce a bit more cumbersome element to my set up at the moment (having to manually move the lens, vs previously everything remote controlled).
post #32 of 46
Quote:
Originally Posted by R Harkness View Post

Thanks.

I'm not sure I've experienced any new revelation. I've planned on the possibility of acquiring an A-lens from the beginning and have inquired about them for years here, while exclaiming all the A-lens set ups I've seen looked wonderful.

As I said, this mostly has to do with the practicalities of my limited throw distance. It does introduce a bit more cumbersome element to my set up at the moment (having to manually move the lens, vs previously everything remote controlled).

Have you tried, just leaving the lens in place full time. That is what I do, using the Lumagen to convert back to 16:9.
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post #33 of 46
Quote:
Originally Posted by R Harkness View Post

Thanks.

I'm not sure I've experienced any new revelation. I've planned on the possibility of acquiring an A-lens from the beginning and have inquired about them for years here, while exclaiming all the A-lens set ups I've seen looked wonderful.

As I said, this mostly has to do with the practicalities of my limited throw distance. It does introduce a bit more cumbersome element to my set up at the moment (having to manually move the lens, vs previously everything remote controlled).

Panamorph has a automated transport that fits it. Was sold under Optoma and Marantz branding, too. See them for sale used regularly if you want to automate it and don't want new.
post #34 of 46
Thread Starter 
Quote:
Originally Posted by AV Science Sales 5 View Post

Have you tried, just leaving the lens in place full time. That is what I do, using the Lumagen to convert back to 16:9.

I don't have a lumagen and I'm not a fan of the idea of leaving the A-lens in place. I only need to use it occasionally.

I guess the Lumagen has a setting where it properly re-shapes the 16:9 image so it comes out correctly when put through an A-lens?
post #35 of 46
Quote:
Originally Posted by R Harkness View Post

I guess the Lumagen has a setting where it properly re-shapes the 16:9 image so it comes out correctly when put through an A-lens?

Yes, it scales/compresses the 16:9 native image to 33% of it's original width. Now the 16:9 material is compressed to 4:3 resolution. Then the lens expands it by 1.33 to get back to 16:9. If you watch an old movie in 4:3, it compresses that to an even narrower strip of video which is then optically expanded to 4:3.

If you move the lens when not required for 2.37, you get the original 16:9 (or 4:3) image unaltered, and in full resolution.
post #36 of 46
Thread Starter 
Quote:
Originally Posted by GetGray View Post

Panamorph has a automated transport that fits it. Was sold under Optoma and Marantz branding, too. See them for sale used regularly if you want to automate it and don't want new.

Thanks.

Yes, ideally I would want the A-lens on a motorized sled too, and I'm aware of the ATH1 Transport for the UH480.

I've been watching the A-lens market for years and I can't recall the last time I saw one of those transports actually for sale second hand, alone. Usually it's a lens/transport being sold together. I'm not sure I can even come up with a reason anyone would sell just their ATH1 Transport if they owned a Panamorph lens.

But if you know of any bargains...I'm all ears.

My issue is that it's been hard to justify spending a lot of money on A-lenses and transports. Unlike most people who use an A-lens every time they switch to scope, I only use it occasionally, just to get those last few inches of width in my set up when I want it.

When my friend came over and saw the Panamorph lens I told him how much I spent on it, which was an incredible bargain. He couldn't believe it was "so expensive." Then I told him how much it was new. He almost fell over. Then I told him how much an electric transport was just to move the lens into position. He literally couldn't comprehend the price "just for a lens to widen the image????!!!!"

The ironic thing is this is a guy who reviews high end audio and is used to insane prices for amplifiers, DACs, speakers not to mention cables. (He once had $18,000 1m long speaker cables at his place).

Anyway, the prices for an A-lens and transport does tend to make the blood run cold, which is why I leapt at this once-in-a-lifetime price for the UH480.
I doubt I'll have any such luck with a remote controlled transport, but I'll be keeping my eyes out.
post #37 of 46
Well, I'd take care of you just due to how long you've been here. But the bracket on the 480 really doesn't fit the CineSlide very well. It's been done, but it's not what the CS was designed for. I had a guy who replaced their Marantz/Isco III transport with a Cineslide and Multistand a few months ago. If you want, feel free to PM me and we can chat off-line. I bet that one is sitting in a box collecting dust. Maybe I can hook you guys up.
post #38 of 46
Thread Starter 
Thanks again GetGray! I know your product is very well regarded so I appreciate your input.
post #39 of 46
Yes Rich if you could get your lens on a CS it would be much better than many others. I have my Schneider mounted on a CS and that slide is certainly a very good piece of equipment, plus its highly accurate every time at where it stops.
post #40 of 46
Thread Starter 
I've been used to having everything in my system automated/remote controlled, including all AR and image size changes. Hence, as much as I'm enjoying the A-lens, moving it manually was getting old fast.

Fortunately it looks like I'm about to pick up a used automated lens sled for my Panamorph lens. (Thanks to GetGray/Scott for giving me a lead).

Question for anyone using these lens sleds: Usually it seems the lens sled is depicted as mounted overtop the projector with the lens hanging down in front of the projector lens.
Do these sleds also work mounting them the opposite way: sled mounted below projector (attached to the projector shelf or whatever) with the lens above the sled?

Or are they designed always to operate with the lens hanging down from the sled portion?

Thanks,
post #41 of 46
Mine (different device) is happy in either orientation. That one uses a plastic friction bearing made by a company called Igus. Igus says it is designed to have the same friction in either orientation. It *should* be happy either way.
post #42 of 46
Thread Starter 
A font of knowledge you are, sir. Thanks.
post #43 of 46
Thread Starter 
So I've had my UH480 Panamorph lens on it's automated sled for a while now. I had to re-build my projector shelf. I made it two tiered, with the shelf holding the A-lens a bit lower than the projector. Works great.
I have it all programmed into my RTI remote system so a single macro engages the anamorphic stretch (from my JVC projector) and slides the lens into the path. Very slick.

I'm still just making my way around using the system this way. Because I bought the lens to help with a shorter throw, I'll have to live with a certain amount of pin cushion, but I've got it to a pretty discrete amount.
I'm still using the zoom method a lot and deciding when I want to do it A-lens style vs zooming - I always use the A-lens for anything larger than a 116" wide scope image. I'm still completely thrilled to have this A-lens set up, allowing my image width to be it's most immersive when I desire it. And the picture quality through the lens can be terrific - I'm quite happy with the sharpness (and I appreciate having the JVC's E-shift MPC processing and a Darbee in the chain, to increase apparent clarity when desired).

Anyway, learning as I'm going, I bumped into an issue that highlighted my naivete. I was all excited about finally watching 2001 A Space Odyssey as wide as it could be shown on my screen, using the A-lens. It wasn't until I engaged the anamorphic stretch that I realized: the processing cuts off some top and bottom of the image! I'd always just figured that an anamorphic stretch simply takes whatever picture information is there, and stretches it to the top and bottom of the screen. But this experience woke me up: I realized that it must be the case that because an A-lens is built to stretch a very particular geometry, the re-scaling/stretching of the image must fit exactly the geometry "expected" by the lens, to come out geometrically correct.

So, in essence, a CIH system using vertical anamorphic stretch and an A-lens like this one treats every anamorphic event as 2:35:1, and the processing will crop the image height to fit that aspect ratio, no matter the original aspect ratio of the movie. And I presume any wider-then-2:35:1 movies will be left with a bit of black bars top and bottom in the image (which can be masked off).

Am I up to speed here?

(To me an A-lens only represented a larger scope image than I can get via zooming, and I'm so used to zooming and masking perfect aspect ratios thatI never gave the actual process of the anamorphic stretch that much thought).

It was something of a disappointment with 2001 since that seemed to be the ultimate "want it as big as possible" movie. It still looked excellent in 2:35:1, but it would have been nice to see the full frame. I was wondering if more sophisticated scalers like a Lumagen somehow allow for retaining the full image of a movie like 2001 when doing anamorphic stretch. But then I'm not sure how that would work in concert with the geometric stretching of the A-lens.
post #44 of 46
Sounds like you are giving the lens "credit" for something it has nothing to do with smile.gif. The lens is designed to be a 1.33x expansion device. Technically, if it were perfect, it would be a process of creating a 2.37:1 image from a 1.78:1 image. Only if the movie is less than 2.37:1 should the 1.33 stretch push any actual video off the 16:9 imaging device.
post #45 of 46
Yes. processors like the Lumagen will allow you to customize the stretch for non-2.35:1 movies while also taking into account the percentage of stretch accomplished by the lens. Maybe Josh Z. will chime in here with more specifics. Personally, I don't usually mess with such settings for reasons I will outline below.

BTW, your thinking about all of this stuff is correct. The VStretch scaling always stretches the picture by a fixed amount, as an anamorphic lens always expands the image by a fixed amount.

As Josh has pointed out here many times, the vast majority of UltraWide movies are going to be transferred to Blu-ray / DVD with a ratio somewhere between 2.35:1 or 2.40:1. Even though the standard has actually been 2.39:1 since 1970, directors and video transfer techs often mess with the picture framing when transferring to video. This explains why a film may have slightly different framing each time it gets transferred. Contrary to popular belief, the framing of an image is almost never calculated down to some kind of precise ratio when shooting. Both directors and DPs will take into account the fact that the film is eventually going to be projected or shown in something other than the original aspect ratio, so frame accordingly. 2001 is an excellent example. Kubrick shot 2001 in 70mm, which has an aspect ratio of 2.20:1. However, the only folks who ever saw 2001 in 2.20 where those who lived near a theater equipped to show 70mm (these theaters were usually only in the biggest cities). Everyone else got to see 2001 cropped down to 2.35:1, just like you experienced it with your system. When Kubrick composed the image, he knew full well that 80 - 90% of viewers would actually get to see it at the 2.35:1 ratio. For that reason, I can't imagine that he put any vital picture information at the very top and bottom of the picture.

Like you said, it looked fine. Unlike panning and scanning - where it is obvious that a picture's original composition has been destroyed - what you are talking about here is pretty much SOP in the filmmaking world. I've been on numerous shoots, and its not like most filmmakers so precisely frame a shot that losing 8% of the top of bottom is going to make any difference at all. In fact, it's amazing how little you can tell about exact framing when you are looking through a tiny viewfinder or video assist monitor, which is that the DP or director are using for framing purposes when setting up a scene.

Hope this helps! And I am very happy to hear you are enjoying your 480. smile.gif
post #46 of 46
Thread Starter 
Looks like I got the general idea. I'm familiar with film production, safe framing etc (having occupied many positions in the industry over time), but for home theater/video projection I'm learning as I go along. For the longest time I couldn't be bothered with home theater projectors because I'd come from watching rushes and prints in various stages in professional environments, and home video projection just looked too much like video blown up trying to be film. I just couldn't buy it, so I went the other way and went with the razzle-dazzle of flat panels. It was the advent of the HD DVD and Blu-Ray era, combined with the leaps in consumer projector performance, that finally brought me into the fold. And now I'm just pinching myself at how good I have it watching movies at home. It's truly a golden age for movie buffs.

Much thanks for the replies.
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