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Discussion Starter · #1 ·
I'm using a 110' screen, so my mounting distance should be 13.9' to 16.8'. Does it matter where in that range for optimal performance? I wouldn't think so.


I plan to mount it near its maximum (16.8'). I'm flexible, but this will get it back far enough so that it is over the second row of seats and not where someone could hit their head on it .. if I had any friends that were taller than 6.5ft ;)


Thanks, Chad
 

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There are a couple of things to consider, IMO. If you want to try and use a constant height screen so that you can zoom out on 2.35:1 aspect ratio movies, then it is very key to get the exact spot to mount the PJ. If you're using 16:9 screen, then that is less important. If you plan to watch any low quality sources, i.e. cable of VHS tapes, then being able to zoom in might be useful, as the picture flaws could be minimized. Lastly, I know the HS20 is much quieter than my HS10, but since it vents out the front having those vents in front of you instead of behind you can reduce the noise you do hear from it.


I ended up moving my HS10 mounting location 3 or 4 times as I went through various configurations. Fortunately I have a suspended ceiling and a DIY mount that made that fairly easy. ;)
 

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Discussion Starter · #4 ·
Is this true? When you zoom, you are moving the lens, not the panels/light source right? Doesn't seem to make sense and also I would think this would be manual for optimal set up. I agree that the large the image the more washed out it will get, but not just for the zoom function.


Technically, if I'm far away from the screen, but w/ the smallest image possible ... wouldn't that be zoom 'in'?


Thanks, Chad
 

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I am not an expert but from what I have learned as you increase the size of the image you are needing more light output to generate as good a picture as you are in a smaller setup. Since the lumen output for the most part is constant you loose some of the light intensity you are getting closer in. I think the same would hold true for the colors, the black and the white.


Backing the projector up opens up the distance the light has to be thrown and I would think that would comprimse the available output... I could be wrong just thinking off the cusp here so please someone jump in a correct me.
 

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Quote:
Originally posted by JDLIVE
If you want to try and use a constant height screen so that you can zoom out on 2.35:1 aspect ratio movies, then it is very key to get the exact spot to mount the PJ.
I've been considering the HS20 and I'm understand the concepts behind a constant height setup, however I have no clue as to exactly how to set it up.


Based on my room dimensions and where the seating area will be, the widest 2.35:1 screen that I can use is 96" which would give me a screen height of approximately 41" (and almost 104" diagonal). If my math is correct that means that for 16x9 material, I'll be looking at a 73" wide screen (almost 84" diagonal), and for 4x3 material the screen will be 54 1/2" wide (about 68" diagonal).


Given this screen size (96" wide), where exactly would I mount the projector? The calculator at PJC only has the option for 16x9, no 2.35:1. Secondly, what needs to be done at the projector and/or the DVD player to display a movie in 2:35:1? Thanks in advance for any information.



Confused in Tampa,


Mikey_C
 

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When mounting my HS20 I noticed that using the zoom resulted in a slightly greater pink fringe on the focus pattern as opposed to being the maximum distance from the screen. My WAG would be about 1/2 pixel less fringe (for about 1.5 total instead of 2) when not using the zoom. This only applies to the edge of the screen, center was perfect in either case.
 

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Mikey_C, the easiest way to look at this is that you want the minimum zoom to be for the 1.78 (16:9) size. From your post, the 84" diagonal gives you a throw distance of 12.7'. The max zoom for the 2.35 size at that distance is 109" diagonal (1.3 x 84") (The HS20 has a 1.3 zoom, not 1.2 that PJ Central uses), or 95" wide. That gives you a 40" screen at that distance, so again it's not perfect, but pretty close. I would make sure and experiment before mounting your PJ for good just to be sure. ;)


The other thing you have to account for is that when you zoom out for 2.35, you need to move the picture, since the zoom also zooms the black bars. I use and HTPC which does it automatically via a preset. The HS20 will let you move the picture display as well, but that would be a manual step each time and I doubt you'd want to live with that. Not sure if any standalone DVD players can do this or not.
 

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Quote:
Originally posted by JDLIVE
The other thing you have to account for is that when you zoom out for 2.35, you need to move the picture, since the zoom also zooms the black bars. I use and HTPC which does it automatically via a preset. The HS20 will let you move the picture display as well, but that would be a manual step each time and I doubt you'd want to live with that. Not sure if any standalone DVD players can do this or not.
Excuse me for being a neophyte, but I'm not sure I follow what you mean by moving the picture because the zoom also zooms the black bars. Could you go into a little more detail? Also, could you explain how an HTPC could do this better than a standalone DVD? Thanks


Still confused...


Mikey_C
 

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It's hard to explain, much easier to see. ;) It has to do with the fact that the center of the lens for an HS10/20 is at the top/bottom of the screen (depending on whether you have a ceiling mount or not). So when you zoom, that edge of the screen does not move. The picture gets larger in all other directions. So say you have a 48" high screen and are showing a 2.35 AR film with the PJ zoomed in to your 16:9 size. The movie part of the image will be approx 36" tall, so you have 6" black bars at the top and bottom. Now zoom that out to max, the image zooms away from the fixed edge of the screen meaning the black bar is zoomed proportionally larger in that direction. Now if you have a 110" wide image, movie portion is nearly 48" high, but the black bar at the top is now bigger, and your 48" movie's top edge is 7" from the top, meaning 7" is also off the screen at the bottom. So you have to be able to shift that picture 7" or so upward. Using Zoom Player on my HTPC, I can do this easily, and it even remembers each movie and knows to shift it automatically. My only standalonde DVD player is a $40 cheapy that I have hooked to my old tube TV for watching DVDs I converted from VHS, so I just don't know whether a standalone player can do this or not. That's just one of the advantages of a HTPC and software based player, you have much more configurability/tweakability.


You could also get around this with a different projector that has "lens shift", I think. I'm just guessing here because the HS10 is my first PJ and it doesn't have that so I'm just speculating....
 
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