Panamorph DC1 Lens - Page 2 - AVS Forum | Home Theater Discussions And Reviews
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post #31 of 54 Old 03-01-2011, 10:09 PM
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Quote:
Originally Posted by Gotchaa View Post
CAVX, did some research and asked Panamorph some of these questions, would appreciate your feedback.

It is my understanding that purely cylindrical lenses compensate for astigmatism by balancing the curvatures of their primary elements against the spacing between them for a certain throw distance. If the throw distance in question is different than the designed throw distance, astigmatism requires an adjustment. Since you can’t change the curvatures of the cylindrical elements you can change the distance separating those elements, and that is what the focus ring does

According to Panamorph, the sweet spot for the DC-1 and UH480 is between 14.5 and 17 ft, outside of that is when you need the correctors.
They market it as a "5 element" lens meaning that is has a corrector built in. If it didn't, it would not be able to focus both V and H at the same time as prisms can not do that on their own. 2 1/2 feet is a big 'sweet' spot.

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It's my understanding that there is also a sweet spot for a cylindrical lens.
All lenses would have a "sweet" spot. Basically because of the design and the ability to adjust the air gap between the lenses, it can be made to focus both V and H lines at any point in the operating range - say from 2m and beyond. A single correction lens can not do that.

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According to Panamorph, their hybrid technology is less sensitive (ie has a larger sweet spot) both for throw distance (against a fixed cylindrical) and lateral alignment. This is why purely cylindrical solutions need to have the adjustment – it goes out of correction faster than the Panamorph hybrid design.
Interesting. A true cylindrical lens can be brought into focus anywhere in the operating range. Yes, you do have to make an adjustment, but once set, that doesn't change unless you change the projection distance. And it operates well outside of 14.5~17 feet.

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post #32 of 54 Old 03-02-2011, 07:40 PM
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I got the DC-1 delivered today, going to set it up with an RS-50 and see how it looks.

Attached is the mounting plate that is for the RS50, it does not require another pole which is nice, we'll see how it actually holds up when mounted.
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post #33 of 54 Old 03-02-2011, 10:15 PM
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That looks neat. Is it powder coated steel or anodized alloy?

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post #34 of 54 Old 03-03-2011, 02:37 PM
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Quote:
Originally Posted by CAVX View Post

That looks neat. Is it powder coated steel or anodized alloy?


Not sure but it's thick and heavy easily between 10-15 lbs. It is pretty sturdy as well. Cosmetically it matches the JVC finish and looks great. I am attaching some iPhone photo's for now.

I have it hanging from a Chief mount 24" from the ceiling using a track mount rated at 500lb attached to the ceiling. It is very sturdy and did not require hanging another pole. The mounting plate clearly changed the center of gravity and shifted the horizontal center which was not an issue due to the ceiling mount I choose which allows me to move the pole horizontally on the track...I though hard about doing a joist mount in the ceiling and decided vertical was not a concern but horizontal movement, based on my joists being horizontal to the screen I choose the ceiling mount option with the horizontal track to allow pole adjustment.

I am about 16' 8" from the screen throwing onto a 122.5" wide and 52" high screen, I believe within Panamorph's sweet spot range and a decent throw ratio (need to calculate). I did some basic alignment late last night and it went very well.

I used the JVC pattern to align the 16:9 image, then slightly zoomed top/bottom. I did not find an option to reset horizontal shift, and I found it difficult to determine the horizontal shift center as there are no values presented in the menu. Also given the ceiling mount and distance, the vertical shift used directly affects the amount of horizontal shift.

Currently I am contemplating leaving the lens in place and using the JVC's Anamorphic mode to squeeze to 16:9.

One thing I did do is measure the native 16:9 image on the screen, and then with the lens in path using JVC's Anamorphic 16:9 mode. I found that native had about 1" more image on each side...I guess the image scaling is not 100% accurate with the JVC+ lens in the light path. It's not that noticeable, but not something I was expecting..

One other note, after initial 16:9 alignment on the screen, and then placing the lens in the light path, the image was shifted to the right. Before mounting the lens, I thought I was compensating for this shift by moving the mounting pole 1" to the left, but I think it was late and in affect I ended up throwing it off center.

The reasoning behind the move was looking at the existing mounting plate and the Panamorph mount plate, what I noticed was it was about 1" shifted so I attempted to compensated for that difference...I didn't think this one through so likely have some additional fine tuning to do.

Focus, I focused without the lens first, then with the lens in the light path, it appeared a bit off, I fine tuned with the JVC controls and it dialed in well. I will revisit this again after further adjustments.

Some basic testing w/ 3:10 to Yuma, it looked great I could not see any pin-cushioning, I know it's there, but not discernible thus far. Test patterns this evening will reveal.

I also could not discern any light output drop, again more testing this evening will reveal. If anyone has suggestions on a reasonably priced light meter let me know. I'll also take a look at the color/contrast shift.
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post #35 of 54 Old 03-03-2011, 02:39 PM
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Here is a link to the Chief Ceiling mount I am using, picture attached
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post #36 of 54 Old 03-03-2011, 04:29 PM
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Quote:
Originally Posted by Gotchaa View Post

Not sure but it's thick and heavy easily between 10-15 lbs.

OK, I'd say powder coated steel

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post #37 of 54 Old 03-04-2011, 02:18 PM
 
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[One thing I did do is measure the native 16:9 image on the screen, and then with the lens in path using JVC's Anamorphic 16:9 mode. I found that native had about 1" more image on each side...I guess the image scaling is not 100% accurate with the JVC+ lens in the light path. It's not that noticeable, but not something I was expecting..]

It will stretch less than 1.33 towards the center and more than 1.33 towards the edges.
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post #38 of 54 Old 03-04-2011, 04:09 PM
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Quote:
Originally Posted by Kenster48 View Post
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[One thing I did do is measure the native 16:9 image on the screen, and then with the lens in path using JVC's Anamorphic 16:9 mode. I found that native had about 1" more image on each side...I guess the image scaling is not 100% accurate with the JVC+ lens in the light path. It's not that noticeable, but not something I was expecting..]
It will stretch less than 1.33 towards the center and more than 1.33 towards the edges.
Yes, what you have measured is commonly known as grid distortion. Basically because the prism faces are flat and when they are rotated to give the appropriate amount of stretch, they tend to over the edges and under stretch the centre. A curved screen may help, however only curved glass can be engineered to truly fix this.

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Quote:


Yes, what you have measured is commonly known as grid distortion. Basically because the prism faces are flat and when they are rotated to give the appropriate amount of stretch, they tend to over the edges and under stretch the centre. A curved screen may help, however only curved glass can be engineered to truly fix this.

I thought all anamorphics had grid distortion? Even ones with curved surfaces. Didn't I read something here recently where even the Isco had this distortion? (Can't find the thread now)
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post #40 of 54 Old 03-05-2011, 12:42 AM
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Quote:
Originally Posted by CAVX View Post

Yes, what you have measured is commonly known as grid distortion. Basically because the prism faces are flat and when they are rotated to give the appropriate amount of stretch, they tend to over the edges and under stretch the centre. A curved screen may help, however only curved glass can be engineered to truly fix this.

Not sure that is the case it's actually a 2" total difference, I am wondering if this is a scaling affect of the JVC anamorphic mode to correct to 16:9. It could be a combination of both lens/scale.
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post #41 of 54 Old 03-06-2011, 11:44 PM
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Quote:
Originally Posted by Gotchaa View Post

Not sure that is the case it's actually a 2" total difference, I am wondering if this is a scaling affect of the JVC anamorphic mode to correct to 16:9. It could be a combination of both lens/scale.

It is an optics issue and will get worse if you shorten the throw.

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post #42 of 54 Old 03-07-2011, 04:39 PM
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Quote:
Originally Posted by Gotchaa View Post

Not sure that is the case it's actually a 2" total difference, I am wondering if this is a scaling affect of the JVC anamorphic mode to correct to 16:9. It could be a combination of both lens/scale.

2" Difference !? In the grid in the middle or side? Yikes.
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post #43 of 54 Old 03-09-2011, 12:24 AM
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2" Difference !? In the grid in the middle or side? Yikes.


Side 1" on each..
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post #44 of 54 Old 03-09-2011, 12:27 AM
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So I did some initial measurements and with the RS50, which is already being scrutinized for Lumens, I measured the following:

In THX mode I measured an average of 457 Lumens @ 17ft throw. I have 214hrs on.

In my calibrated Cinema mode, I measure 417 Lumens.

With the DC-1 in THX mode I drop to 349 Lumens, and 309 Lumens for Cinema mode..


In terms of color/sharpness, on test patterns with Spears & Munsil disc, I could not discern any changes at all.

More to come...
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post #45 of 54 Old 03-31-2011, 01:02 AM
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So I took some more measurements in 4 different scenarios to try and capture the DC-1's light transparency. I'm at a 17ft throw, details are in attached PDF with test criteria.
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post #46 of 54 Old 04-01-2011, 07:22 AM
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Very interesting. Thanks for the hard work.
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post #47 of 54 Old 04-05-2011, 11:43 PM
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Quote:
Originally Posted by Gotchaa View Post
So I took some more measurements in 4 different scenarios to try and capture the DC-1's light transparency. I'm at a 17ft throw, details are in attached PDF with test criteria.
Folks, I have to repost this. Apparently after reviewing my findings with UMR he pointed out that I left the 16:9 screen area measurement in Ron's chart set to 2.35:1 when measuring 16:9 native mode, no lens.

Since I am doing a CIH with my A-lens and 2.35 screen, the measurement for a 16:9 mode should maintain the screen height for the sq ft and proper image area measurement of the JVC's 16:9 native throw. Doh!

Accordingly when using the Panamorph DC-1 A-lens, and switching to Anamorph B mode to squeeze down to 16:9 it should remain 2.35:1 as the JVC is scaling with the A-Lens in place already applying it's optical stretch to 2.35:1.

If you disagree with the above please explain why, assuming Ron's calculations are accurate as you will see CIH is approximately 52.7-52.8" on all measurements now.

The good news is for Panamporh DC-1. It does appear to be about 96.875% light transparent if you compare the Lumens output of 16:9 mode native with no lens at the corrected value of 256 Lumens to 2.35:1 with the lens in line at 248 Lumens output.

Unfortunately if this is correct the Lumens are actually lower for the JVC RS50 than expected.

I'll measure again when I hit 400hrs.

 

RS50 Lumens Measurement v2 Test Mode Criteria.pdf 37.2138671875k . file

 

RS50 Lumens Measurement v2 pdf.pdf 49.5615234375k . file
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File Type: pdf RS50 Lumens Measurement v2 pdf.pdf (49.6 KB, 76 views)
File Type: pdf RS50 Lumens Measurement v2 Test Mode Criteria.pdf (37.2 KB, 49 views)
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post #48 of 54 Old 09-04-2018, 05:24 PM
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Help

Gentlemen, I purchased a DC1 from another member who had never opened it. (He bought it from another member years ago). Everything was in like-new (or actually new) condition.

Long story short, I had an accident while mounting the AK8-ATH2-DC1 assembly. The weight of the AK8 plate contributed to the DC1 shattering. I was crushed. After sleeping on it I re-examined the damage and it seemed like it can possibly be salvaged.

The front glass was only chipped, outside of the light path. The rear glass was ruined. It seems to be a basic, cheap glass. I'm not sure it did/does anything other than protect the optics. Does anyone know? Do I need to get this glass replaced or just clean the inner lens periodically?

The lens seems to still be functional when I hold it in front of the projector (JVC RS620 not yet amounted, awaiting Chief extension pole). I haven't heard back from Panamax yet. I've epoxied the housing back together and it is curing.
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post #49 of 54 Old 09-05-2018, 09:05 AM
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Quote:
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Long story short, I had an accident while mounting the AK8-ATH2-DC1 assembly. The weight of the AK8 plate contributed to the DC1 shattering. I was crushed. After sleeping on it I re-examined the damage and it seemed like it can possibly be salvaged.
I feel for you. That is so unfortunate. You may want to consult your homeowners insurance to see if a claim would be worthwhile. If you used a creditcard through paypal there may be insurance for damage to purchases as well.

Best of luck!
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post #50 of 54 Old 09-29-2018, 03:57 PM
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The rear glass was ruined. It seems to be a basic, cheap glass. I'm not sure it did/does anything other than protect the optics. Does anyone know? Do I need to get this glass replaced or just clean the inner lens periodically?
That is the astigmatism correction lens. It is a properly ground lens to help bring focus to the vertical lines. Anamorphic adapters will pass horizontal lines with no defects, but the vertical lines need to be focused. Without this lens, you will have to rock the focus of the primary lens in the projector and find the point that kind of fudges both vertical and horizontal lines together.

I'd be contacting Panamorph for a replacement. Not sure what it is going to cost you but I seem to remember change out lenses for the uh380 and uh480 being around $1500.

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Last edited by CAVX; 09-29-2018 at 04:04 PM.
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post #51 of 54 Old 09-29-2018, 06:10 PM
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Originally Posted by CAVX View Post
That is the astigmatism correction lens. It is a properly ground lens to help bring focus to the vertical lines. Anamorphic adapters will pass horizontal lines with no defects, but the vertical lines need to be focused. Without this lens, you will have to rock the focus of the primary lens in the projector and find the point that kind of fudges both vertical and horizontal lines together.

I'd be contacting Panamorph for a replacement. Not sure what it is going to cost you but I seem to remember change out lenses for the uh380 and uh480 being around $1500.
Thanks so much. I never got a response back but I'll keep trying. Maybe I need to pretend I'm in the market for a Palladin.

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post #52 of 54 Old 01-12-2019, 10:58 PM
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Does anyone know if the DC1 lens will work with the new JVC 4K/8K projectors? specifically the NX9? I am hoping it does and I wont need to sell mine. Currently using it with my JVC 990.

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post #53 of 54 Old 03-31-2019, 11:48 PM
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Anyone? Should have my NX-9 this thursday and hoping I dont need to replace my DC1 to enjoy 4k

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post #54 of 54 Old 04-02-2019, 11:59 AM
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Does anyone know if the DC1 lens will work with the new JVC 4K/8K projectors? specifically the NX9? I am hoping it does and I wont need to sell mine. Currently using it with my JVC 990.
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Anyone? Should have my NX-9 this thursday and hoping I dont need to replace my DC1 to enjoy 4k
It should work. Although the chip in the NX-9 is 4096X2160, the projector has a 16:9 mode, so the DC1 you have can expand the 16:9 image properly.
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