JVC RS57 - 144" 2:35:1 Screen CIH - Help - AVS Forum
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post #1 of 27 Old 02-15-2014, 02:17 PM - Thread Starter
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I'm in the home stretch of making some final decisions before sheetrock is installed in my basement. I have decided on projector (JVC RS57) and screen material (Black Diamond 1.4 - will have some ambient light during daytime viewing of HDTV, etc.).

Viewing is about 55% HDTV, 25% Movies and 20% Games (PS4 mainly). Almost 100% of the movie viewing would take place at night in nearly blacked out conditions.

I was pretty set on a 115" 16:9 screen but am thinking now that if I'm going to do this and the projector has lens memory, I might as well do a CIH setup (using the lens memory now but possibly doing an anamorphic lens later).

A 144" 2:35:1 screen gives me the largest 2:35:1 available in the BD Zero Edge model and still gives me the same 115" image for 16:9 viewing I would have had otherwise. It just barely fits inside my LR in wall speakers.

A few questions:

1. If I'm calculating projector light on the screen, I can calculate both AR's as if they were separate screens, correct? My 16:9 fL would be just plugging in the values for the 115" diagonal 16:9 screen (34fL) and my 2:35:1 would just be plugging in values for the 144" diagonal 2:35:1 screen (23fL)? Or is my light output on the screen reduced by the zoom?

2. In the above calcs, I used 17' 6" as the throw distance. JVC says that when you use lens memory for 16:9 and 2:35:1 then the throw range is reduced to 1.4:1 - 2.1:1 so I think that 17' 6" is basically the furthest I can be from the screen, correct? If that's right, then my throw ratio for 2:35:1 viewing will be just slightly under 1.6 (1.5909 to be exact). I know 1.6 is the magic ratio for pincushion distortion... will this be an issue considering I am just slightly below it?

3. The wall that my projector will be on will be matte paint, as close to black as possible within the shades we are using (ie it might end up being a very, very dark navy). Any consideration to light spill over the top and bottom of the screen when viewing 2:35:1 content?

4. How distracting or "annoying" is the unused space on the right and left of the 16:9 image? I hadn't planned for or budgeted for any type of curtains or masking and moving to the 2:35:1 would be stretching the budget slightly anyway so those would probably have to wait. I've been seeing top and bottom letterboxing for years on my 16:9 displays and I can't say that it bothers me greatly.

5. Since this is a multi-purpose room, there will only be one seating row and it will probably be a large sectional at around 13-14'. Any issues there?

Thanks for helping a rookie here. I have a A/V experience but was never a projector buff so I'm diving head first back in. Looking to lock the screen order in Monday.
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post #2 of 27 Old 02-18-2014, 08:18 AM
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Quote:
Originally Posted by JohnLew View Post

1. If I'm calculating projector light on the screen, I can calculate both AR's as if they were separate screens, correct? My 16:9 fL would be just plugging in the values for the 115" diagonal 16:9 screen (34fL) and my 2:35:1 would just be plugging in values for the 144" diagonal 2:35:1 screen (23fL)? Or is my light output on the screen reduced by the zoom?

You have to remember that the projected area of the zoomed image is 78% larger than that of the 16:9 image (1.33x in both directions), though with the JVCs, the actual light output goes up some when you zoom partially offsetting it. You'll want to use a 16:9 screen the same width as your 2.35:1 screen to calculate brightness for that screen.
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2. In the above calcs, I used 17' 6" as the throw distance. JVC says that when you use lens memory for 16:9 and 2:35:1 then the throw range is reduced to 1.4:1 - 2.1:1 so I think that 17' 6" is basically the furthest I can be from the screen, correct? If that's right, then my throw ratio for 2:35:1 viewing will be just slightly under 1.6 (1.5909 to be exact). I know 1.6 is the magic ratio for pincushion distortion... will this be an issue considering I am just slightly below it?

Pincushion only applies when using a horizontal expansion anamorphic lens.
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4. How distracting or "annoying" is the unused space on the right and left of the 16:9 image? I hadn't planned for or budgeted for any type of curtains or masking and moving to the 2:35:1 would be stretching the budget slightly anyway so those would probably have to wait. I've been seeing top and bottom letterboxing for years on my 16:9 displays and I can't say that it bothers me greatly.

Depends on who you ask, it doesn't bother me at all, but some people really like ("need") anything unused to be masked.

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post #3 of 27 Old 02-18-2014, 12:41 PM
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A few additional points (Stanger89's answers are excellent, btw) -

1. Zooming also means that your projector's light output is reduced by 25% when watching letterboxed material (as 270 rows of pixels are shut off to "draw" the black bars). As Stanger89 says, you want to calculate your brightness as if you are using a 16:9 screen of the same width as your 2.35:1 screen. Since the JVC projector actually gives you more brightness as you zoom, that offset gives you a little extra brightness to play with when all is said and done.

2. 17.6' is an excellent throw distance for that size screen, especially if you add an anamorphic lens later. Pincushion will be minimal when / if you add an anamorphic lens (Panamorph recommends at least 3X screen height - you are further away than that, so pincushion will be less). The "1.6" throw figure is calculated from the 16:9 width, not the 2.35:1 width.

3. The dark paint will help greatly for hiding the black bar overspill.

4. The Black Diamond uses black screen material; this makes the side bars VERY hard to notice.

5. FWIW, I am sitting about 14' back from a 144" Stewart StudioTek (11 foot wide) with a JVC projector paired with a Panamorph DC1 lens (very similiar to your configuration). I find it a very comfortable setup.

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post #4 of 27 Old 02-18-2014, 12:57 PM - Thread Starter
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Thanks guys, that helps a lot. Clears up some things for me.

I've got the screen and projector ordered so I'm off and running.

Regarding the throw distance and pincushion, I understand it's not an issue when I'm using the zoom feature, which will be how I start. I may add the anamorphic lens later and want to kind of plan for that as well. If I decide to throw at 16' instead of 17' 6" am I going to potentially have problems with the lens. 16' works much better with the planned seating. If I will have issues, I think I'm going to rough in a second projector location at 17' 6" so that I can move the projector back later if I add the lens.
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post #5 of 27 Old 02-18-2014, 03:01 PM
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Quote:
Originally Posted by John Schuermann View Post

1. Zooming also means that your projector's light output is reduced by 25% when watching letterboxed material (as 270 rows of pixels are shut off to "draw" the black bars). As Stanger89 says, you want to calculate your brightness as if you are using a 16:9 screen of the same width as your 2.35:1 screen. Since the JVC projector actually gives you more brightness as you zoom, that offset gives you a little extra brightness to play with when all is said and done.

Can I go down into the weeds for a minute? biggrin.gif

If we assume a baseline brightness, lets call it "100", for a 16:9 image, then in reality everything else is dimmer, it's a question of how much.

If you place a lens in front of it, you take the same amount of light, "100", and spread it over an area 33% larger (1.33x, 4/3), this means that the brightness is 25% lower (the wonder of reciprocals 4/3 -> 3/4), so you're light output with a lens is "75"

If you zoom, you are now taking that same amount of light, "100", and spreading it over an area 78% larger (1.33*1.33=1.78x), so this means that the brightness is 44% lower, so your light output is now by zooming "56". FWIW, this is where the 33% "gain" comes from when people talk about a lens, 75/56 = 1.33, or 33% brighter.

However, there is a complication, projectors don't output the same amount of light when in long vs short zoom, so when you zoom in, the light output increases. This can range anywhere from maybe 10% to as much as 30% depending on the projector and where in the throw range you are. Suffice to say, this increase in output makes up for a portion of the difference in brightness between zooming and using a lens. I think Cine4home did a test with a Panasonic (AE3000 maybe?), and the net difference between a lens and zooming was essentially zero.
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post #6 of 27 Old 02-18-2014, 11:31 PM
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Originally Posted by stanger89 View Post

Can I go down into the weeds for a minute? biggrin.gif

If we assume a baseline brightness, lets call it "100", for a 16:9 image, then in reality everything else is dimmer, it's a question of how much.

If you place a lens in front of it, you take the same amount of light, "100", and spread it over an area 33% larger (1.33x, 4/3), this means that the brightness is 25% lower (the wonder of reciprocals 4/3 -> 3/4), so you're light output with a lens is "75"

If you zoom, you are now taking that same amount of light, "100", and spreading it over an area 78% larger (1.33*1.33=1.78x), so this means that the brightness is 44% lower, so your light output is now by zooming "56". FWIW, this is where the 33% "gain" comes from when people talk about a lens, 75/56 = 1.33, or 33% brighter.

However, there is a complication, projectors don't output the same amount of light when in long vs short zoom, so when you zoom in, the light output increases. This can range anywhere from maybe 10% to as much as 30% depending on the projector and where in the throw range you are. Suffice to say, this increase in output makes up for a portion of the difference in brightness between zooming and using a lens. I think Cine4home did a test with a Panasonic (AE3000 maybe?), and the net difference between a lens and zooming was essentially zero.

Good breakdown.

We've measured all kinds of different results, lens vs. zoom. From our testing average brightness increase is about 20%, some more some less. Sony engineers in Japan just got done evaluating a Panamorph DC1 with their 4K consumer projectors and reported back to us an average 20% increase.

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post #7 of 27 Old 02-18-2014, 11:32 PM
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Originally Posted by JohnLew View Post

Thanks guys, that helps a lot. Clears up some things for me.

I've got the screen and projector ordered so I'm off and running.

Regarding the throw distance and pincushion, I understand it's not an issue when I'm using the zoom feature, which will be how I start. I may add the anamorphic lens later and want to kind of plan for that as well. If I decide to throw at 16' instead of 17' 6" am I going to potentially have problems with the lens. 16' works much better with the planned seating. If I will have issues, I think I'm going to rough in a second projector location at 17' 6" so that I can move the projector back later if I add the lens.

Just speaking for Panamorph, 16 feet is ideal - precisely in the sweet spot.

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post #8 of 27 Old 03-07-2014, 06:03 PM
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You will be very happy with hour RS57. I have the same projector, using a similar throw and a 2.35:1 screen about the same size as yours (seymour AV, 1.2 gain though).

An anamorphic lens was on my soon to buy list, but I am so happy with the picture the JVC throws when zooming for 2.35:1 content that I decided not to get one. I use low lamp mode for 16:9 and high mode for 2.35:1. eShif is always on and there is no pixel to be seen from my seating location. Zooming is fast and precise, and I easily programmed 6 different lens memories that I can access with the press of a single button.

I use side masking panels for 16.9. The vertical black bars look VERY dark on this JVC, but with the panels, the screen seems to magically float in front of me, surrounded by pitch black velvet.

My advice: dont buy the lens now. Use the zooming method. See if you are happy with it or not. If not, test your setup with an anamorphic lens before buying one (easier said than done).

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post #9 of 27 Old 03-11-2014, 12:05 AM - Thread Starter
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Originally Posted by stef2 View Post

You will be very happy with hour RS57. I have the same projector, using a similar throw and a 2.35:1 screen about the same size as yours (seymour AV, 1.2 gain though).

An anamorphic lens was on my soon to buy list, but I am so happy with the picture the JVC throws when zooming for 2.35:1 content that I decided not to get one. I use low lamp mode for 16:9 and high mode for 2.35:1. eShif is always on and there is no pixel to be seen from my seating location. Zooming is fast and precise, and I easily programmed 6 different lens memories that I can access with the press of a single button.

I use side masking panels for 16.9. The vertical black bars look VERY dark on this JVC, but with the panels, the screen seems to magically float in front of me, surrounded by pitch black velvet.

My advice: dont buy the lens now. Use the zooming method. See if you are happy with it or not. If not, test your setup with an anamorphic lens before buying one (easier said than done).

Great, thanks. It's been a brutal wait, the projector has been sitting in my office upstairs boxed for about 2 weeks now smile.gif Painting in the basement will be finished on Wednesday and my screen should arrive sometime between now and the end of the week so I'm hoping to be installing it this weekend, even if it means I'll be sitting on folding chairs for 10 days or so while we wait for trim and carpet.

My hope is that the fact that the BD screen is very dark by itself will help kind of "auto-mask" the pillarboxing on the 16:9 content. If not, I'll have to look into some type of masking solution but I think the BD Zero Edge frame will limit my options.
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post #10 of 27 Old 03-16-2014, 11:00 PM - Thread Starter
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Okay, I've got the projector mounted to the ceiling and the screen on the wall, everything looks great.... but...

I can't seem to get the 2.35:1 image correct. I zoom the image out so that it meets the edges of the screen horizontally but it does not meet the top and bottom, I am still left with small black lines there (roughly 1"). 16:9 looks fine, zoomed out to the top and bottom and obviously the sides could be "off" and you would never notice with the pillarboxing.

I think the screen is centered horizontally to the screen (or is very, very close) and I am not using any horizontal shift when doing this (I centered the lens using the menu and then only used vertical shift). My projector is about 2" higher than the top of the screen. Does the projector need to be at or below the top of the screen vertically in order for this to work properly? I could get a longer extension column if needed.

Also, a secondary issue is recalling the lens memories. Why does it seem that the shifts don't go back exactly correctly when recalling the lens memory positions? It's not as noticeable when I'm not using horizontal shift but seems like the vertical doesn't return exactly to the stored position either.

Anyone have any ideas? I am using at PRG-UNV mount so I've adjusted the pitch and roll to have it correctly aligned. I've verified with my level that the screen is mounted level. I guess the projector could be slightly swiveled on the extension column (it looks like it's aligned parallel) but I don't even know if that would cause what I'm seeing.

Very frustrating trying to get it perfect.

Thanks.
-john
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post #11 of 27 Old 03-16-2014, 11:25 PM
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Well many movies are 2.40:1 so will be a little skinnier top and bottom than a 2.35:1 screen. Most of us just let a couple inches fall over the sides, so the top and bottom fill the screen, and call it a day.

People with anamorphic lenses are actually projecting a 2.37:1 image so that's not perfect either.

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post #12 of 27 Old 03-17-2014, 03:27 PM
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Keep in mind too that perfect is relative. Next time you go to the theater you will notice that overspill is standard even in pro installations.

That said, the 2.35:1 zoom should fill a 2.35:1 almost exactly. It sounds like you are trying to get a 2.40:1 image to fit a 2.35:1 screen. This is fine, as most movies are actually 2.40:1 anyway. You are expected to zoom the overspill into the black screen surround.

Zoom memory losing position over time is something we hear about at Panamorph fairly often. I can't really draw any conclusions from that as to how prevalent the issue is, since people don't call in to complain when things are working properly wink.gif It would be interesting to hear others chime in to report their experiences, positive and negative.

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post #13 of 27 Old 03-17-2014, 07:24 PM - Thread Starter
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Thanks, guys. I'm going to do some measurements to see if I'm seeing the 2.40:1 on a 2.35:1 screen issue. Based on my calculations for the BD Zero Edge 2.35:1 144" diag (132.625" width, 56.38" height), a 2.40:1 image on that screen should leave approx. 1.2" of letterboxing. If that's the case, I'll prob just live with the sliver of letterboxing on that content as I am crunched for horizontal space to my speakers anyway. There is only about .75-1" of space between the screen sides and the speaker grill, meaning any overspill on the sides is going to be hard to hide so that it's not distracting.

Does anyone know if the widescreen lines the JVC displays on the alignment pattern are 2.35 or 2.40? I can't get those to align properly either, which would make sense if they are 2.4 but not if they are 2.35.

And, John, the "loss of position" I'm talking about with the lens memory isn't happening over time. The first time the projector was set up was yesterday and I could literally set the lens memory, go to a different aspect ration, then recall the saved position and it wouldn't get it exactly right just minutes later.
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post #14 of 27 Old 04-25-2014, 06:39 AM
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I am a bit confused by all of this.  I am still in the 'design' phase, but will shortly be needing to determine 'where' to do the rough-in wiring & bracing work for a projector. 

 

I am leaning towards a JVC RS57, planning to use an Acoustically Transparent Screen, I think a 1.1ish gain.   I am also leaning towards a 144" diagonal 2.35:1 screen.  I want to be able to do "CIH" via the Zoom feature as well.  I will have the ability to be in a 'totally dark' room (there are no windows, I'll have lights on a dimmer which could obviously be shut off).   My room itself is ~ 23' x ~ 17.5' x ~ 8'8" (not planning a soffit, but if I do, that would drop the 'ceiling' height to closer to 8').  I am guessing my 1st row seating will be in the 11'-12' range from eyes, and 2nd row ~ 6 1/2' back from there.  

 

If I go to Projectorcentral.com or eliteprojectcalculator.com, they seem to recommend mounting further back - call it closer to 20'.   

 

I plan to eventually get a projector first, then play with a few screen dimensions to determine what I deem as 'comfortable', and then buy the screen - but the above is my tentative/ initial thoughts. 

 

Thoughts?  Is the 20' too far away?  I could simply be inputting data into the calculators the wrong way, I am fairly new at all of this.

 

Thanks,

Kevin

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post #15 of 27 Old 04-25-2014, 09:51 AM
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Quote:
Originally Posted by kmhvball View Post

I am a bit confused by all of this.  I am still in the 'design' phase, but will shortly be needing to determine 'where' to do the rough-in wiring & bracing work for a projector. 

I am leaning towards a JVC RS57, planning to use an Acoustically Transparent Screen, I think a 1.1ish gain.   I am also leaning towards a 144" diagonal 2.35:1 screen.  I want to be able to do "CIH" via the Zoom feature as well.  I will have the ability to be in a 'totally dark' room (there are no windows, I'll have lights on a dimmer which could obviously be shut off).   My room itself is ~ 23' x ~ 17.5' x ~ 8'8" (not planning a soffit, but if I do, that would drop the 'ceiling' height to closer to 8').  I am guessing my 1st row seating will be in the 11'-12' range from eyes, and 2nd row ~ 6 1/2' back from there.  

If I go to Projectorcentral.com or eliteprojectcalculator.com, they seem to recommend mounting further back - call it closer to 20'.   

I plan to eventually get a projector first, then play with a few screen dimensions to determine what I deem as 'comfortable', and then buy the screen - but the above is my tentative/ initial thoughts. 

Thoughts?  Is the 20' too far away?  I could simply be inputting data into the calculators the wrong way, I am fairly new at all of this.

Thanks,
Kevin

The easiest way to calculate your throw range is to look at the 16:9 screen size and the converted 16:9 screen size for the 2.35:1 screen.

So a 144" 2.35:1 screen has dimensions of 132x56". To calculate the 16:9 screen size you use the height. So that give us a 16:9 image of 99.5x56". The next size is the blown up 16:9 image size. When zooming the image is still 16:9, we're just letting the bars spill over. So in this case we use the width to calculate. So the 16:9 image we're projecting for 2.35:1 is 132x74.3". When you plug those screen sizes into the calculator you get:

16:9 : 11'7"-23'3"
2.35:1 (using the 16:9 size): 15'5"-30'10"

So the range to use the zoom method is 15'5"-23'3". I don't like going to the edge of either. I tend to sacrifice brightness for the better black level of a longer throw so I would go towards the long end. Probably 18-20'. If you want it closer and brighter I'd start at 16'.

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post #16 of 27 Old 04-25-2014, 11:00 AM
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Originally Posted by jeahrens View Post


The easiest way to calculate your throw range is to look at the 16:9 screen size and the converted 16:9 screen size for the 2.35:1 screen.

So a 144" 2.35:1 screen has dimensions of 132x56". To calculate the 16:9 screen size you use the height. So that give us a 16:9 image of 99.5x56". The next size is the blown up 16:9 image size. When zooming the image is still 16:9, we're just letting the bars spill over. So in this case we use the width to calculate. So the 16:9 image we're projecting for 2.35:1 is 132x74.3". When you plug those screen sizes into the calculator you get:

16:9 : 11'7"-23'3"
2.35:1 (using the 16:9 size): 15'5"-30'10"

So the range to use the zoom method is 15'5"-23'3". I don't like going to the edge of either. I tend to sacrifice brightness for the better black level of a longer throw so I would go towards the long end. Probably 18-20'. If you want it closer and brighter I'd start at 16'.


Thanks a lot, I now get it!   I appreciate the help!

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post #17 of 27 Old 07-08-2014, 01:23 PM
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So have you found the JVC/144" scope screen combo provides a bright enough image?
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post #18 of 27 Old 07-08-2014, 01:46 PM
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So have you found the JVC/144" scope screen combo provides a bright enough image?
I would like to hear if anyone else has thoughts on this too...

A key question is what Screen is used, and is it Acoustically Transparent or not, and what is the Gain.

Acoustically transparent screens allow light through them, so aren't as bright. Mike Garrett at AVS Science recommends no wider than a 130" wide 2.35:1 for optimal picture...

Also, apparently the JVC-DLA49/4910 is a bit brighter, so, I am leaning that direction now since the larger screen is my primary objective (vs darker blacks).

I am going to set electric & low voltage connections far enough back to accommodate the 144" screen, and then mock up a screen when I get to that stage (seemingly months and months from now) and 'test it out'.

I am doing 'in-wall' speakers, which, I have decided to mount inside the shell of the room. That also gives me some latitude, so, I can place those wider or narrower depending on the screen width. The Spaceman theater build was the example I found which gave me the idea for doing the 'in walls' later.

Last edited by kmhvball; 07-08-2014 at 01:48 PM. Reason: mention jvc 49 vs 57
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post #19 of 27 Old 07-09-2014, 06:12 AM
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Quote:
Originally Posted by kmhvball View Post
I would like to hear if anyone else has thoughts on this too...

A key question is what Screen is used, and is it Acoustically Transparent or not, and what is the Gain.

Acoustically transparent screens allow light through them, so aren't as bright. Mike Garrett at AVS Science recommends no wider than a 130" wide 2.35:1 for optimal picture...

Also, apparently the JVC-DLA49/4910 is a bit brighter, so, I am leaning that direction now since the larger screen is my primary objective (vs darker blacks).

I am going to set electric & low voltage connections far enough back to accommodate the 144" screen, and then mock up a screen when I get to that stage (seemingly months and months from now) and 'test it out'.

I am doing 'in-wall' speakers, which, I have decided to mount inside the shell of the room. That also gives me some latitude, so, I can place those wider or narrower depending on the screen width. The Spaceman theater build was the example I found which gave me the idea for doing the 'in walls' later.
So are you thinking a 144" 2.35:1 non-acoustincally transparent screen (say 1.3 gain) would be most certainly be bright enough?
I'm considering a Screen Innovations Pure White 4k 1.3 and I can get a solid deal on a JVC but have been worried it would be too dim.
Thanks.
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post #20 of 27 Old 07-09-2014, 10:23 AM
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Quote:
Originally Posted by Ccondo1 View Post
So are you thinking a 144" 2.35:1 non-acoustincally transparent screen (say 1.3 gain) would be most certainly be bright enough?
I'm considering a Screen Innovations Pure White 4k 1.3 and I can get a solid deal on a JVC but have been worried it would be too dim.
Thanks.
I would have to defer to Mike Garrett at AVS Science... He seems to have some program to load the 'specs' into, and that pops out the Foot Lamberts of Light (and he knows the range it should be in).
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post #21 of 27 Old 07-09-2014, 11:41 PM
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Quote:
Originally Posted by Ccondo1 View Post
So are you thinking a 144" 2.35:1 non-acoustincally transparent screen (say 1.3 gain) would be most certainly be bright enough?
I'm considering a Screen Innovations Pure White 4k 1.3 and I can get a solid deal on a JVC but have been worried it would be too dim.
Thanks.
I'm using a 136" 2.35 non-AT Carada BW 1.3 gain screen with my JVC RS50. It's bright enough - at least in my light-controlled room... I'd hope the RS57 would outperform it!

Jeff

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post #22 of 27 Old 07-10-2014, 04:50 AM
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Originally Posted by jautor View Post
I'm using a 136" 2.35 non-AT Carada BW 1.3 gain screen with my JVC RS50.

Jeff
Hi Jeff... is yours 136" Diagonal, and ~124" Wide?

The dimensions I was originally referring to were in "Width" vs Diagonal, not sure which the poster who asking about the 1.3, non-at screen, was referring to though.

I guess as I re-read... my comments regarding Mike Garrett were talking "Width" of Screen vs Diagonal. My earlier post from back in April were referring to Diagonal... but, the latest one's were referring to "Width".

Last edited by kmhvball; 07-10-2014 at 04:53 AM. Reason: Revised Thought...
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post #23 of 27 Old 07-10-2014, 07:26 AM
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Originally Posted by kmhvball View Post
Hi Jeff... is yours 136" Diagonal, and ~124" Wide?
Yes, mine is 136" diagonal in 2.35 (~108" in 16:9). OP was asking for a 144" diagonal (since the 16:9 size is 115").

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post #24 of 27 Old 07-10-2014, 07:48 AM
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Quote:
Originally Posted by jautor View Post
OP was asking for a 144" diagonal (since the 16:9 size is 115").
Agreed, clearly Post 1/ OP of the thread was talking the 144" Diagonal.

I wasn't sure about post 19 though., and if the re-opener, was thinking the same 144" Diagonal... it would seem to make sense given the very original post was Diagonal!
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post #25 of 27 Old 07-16-2014, 12:58 PM
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Quote:
Originally Posted by Ccondo1 View Post
So are you thinking a 144" 2.35:1 non-acoustincally transparent screen (say 1.3 gain) would be most certainly be bright enough?
I'm considering a Screen Innovations Pure White 4k 1.3 and I can get a solid deal on a JVC but have been worried it would be too dim.
Thanks.
I am running a JVC HD950 on a 144" diagonal 2.35:1 Stewart StudioTek130. It is bright enough for my environment with the iris open and the bulb on low (standard) setting. For width reference, the screen is 11 feet wide. Of course, I am using a lens (the Panamorph DC1), so that helps with brightness.

I often tell people that they can go even bigger, but that they will want to replace bulbs well before they hit their full life expectancy. I usually replace bulbs after approx. 1000 hours (when they really start to dim, in my experience).

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post #26 of 27 Old 08-16-2014, 05:54 PM
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I have been using my first PJ for about two years now, A JVC X30 on a Vutec 138" (diaganol) screen (purchased through AVS with the help of Mike Garret)

I am no HT expert at all and pretty much just watch BD movies from a PS3, no lens, just the zoom and I absolutely LOVE IT! I am so glad that I listened to the folks on this forum and to Mike Garret.

While watching movies, we constantly comment on how awesome the picture is for a 1080p PJ!!

And my JVC needs adjustment every time after switching aspect ratios.

My next PJ will probably not be until the 4Ks are affordable and I will step up the screen size a bit

Last edited by EricU; 08-17-2014 at 11:04 AM.
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post #27 of 27 Old 08-31-2014, 07:18 PM
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I use the zooming method with my RS57. My 2.35:1 screen is 124 inches wide (SeymourAV AT screen) and I get 12 fL after 500h on the lamp. I am so glad I didnt spend thousands of dollars on a lens to get more lumens...

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