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Go Back   Blu-ray Forum > Displays > Projectors

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Old 02-01-2013, 02:08 PM   #1
GeneticMutation GeneticMutation is offline
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Sorry if this has been asked or is a really dumb question!

As you can guess I'm a projector noob and was wondering what all the ratios and the like mean? I've had a look on a few websites which try to explain Dimension divide Width and other calculations I just don't understand!

My question is do people really use these "calculations" or do they / you just buy a projector, set it up and wam bam you have a huge screen?

If anyone would like to help / explain how this all works it would be much appreciated, oh and if you are going to explain please do so in a way that Harry and Lloyd would understand lol!

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Old 02-01-2013, 03:19 PM   #2
ImPulSive ImPulSive is online now
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Have you visited http://www.projectorcentral.com/proj...ulator-pro.cfm ?

May not answer your questions, but if you know the size of your room, the size of the screen, and the light control, it can help you decide about how bright of PJ you will need, its placement, screen size, brightness, etc. Helps to put you in the general ball park and pseudo evaluate various screens and PJs.
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Screen: Carada Precision 126 inch 1.78 BW Fixed Frame PJ: Epson 8700UB (2D) Panasonic AE7000U (3D)
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Old 02-01-2013, 03:52 PM   #3
GeneticMutation GeneticMutation is offline
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Quote:
Originally Posted by ImPulSive View Post
Have you visited http://www.projectorcentral.com/proj...ulator-pro.cfm ?

May not answer your questions, but if you know the size of your room, the size of the screen, and the light control, it can help you decide about how bright of PJ you will need, its placement, screen size, brightness, etc. Helps to put you in the general ball park and pseudo evaluate various screens and PJs.
I have had a little play on this but not sure if I'm using it correctly

The longest part of my room is about 11 feet (I'll post correct measurements when I get home) which projector would you recommend? It'll be in a living room with a large EAST facing window but the projector will mostly be used in the evenings for blu ray movies, SKY HD and a little PS3 gaming.

We rarely watch TV during the day as we both work and at weekends are always busy or out visiting!

EDIT: I've been looking primarily at Epson projectors as they seem to get the most amount of praise over on AVForums!
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Old 02-01-2013, 04:21 PM   #4
Flatnate Flatnate is offline
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Most of the math that surfs around the site is just making sure you can project an image of a certain size with a specific throw distance. This ensures your buying a screen that you can actually make work given a specific throw distance that you can't change from your room. That calculator page over at Projector Central is way better than doing it by hand as it just automatically gives you a range for any entered set of values. I think Epson has a similar calculator on their website as well for each given model... well at least on the North American site.

You can do math on other things like recommended seating distance, recommended brightness for a certain size screen; but really that projector calculator for size and throw over at Projector Central is what matters for most people.
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Old 02-01-2013, 04:22 PM   #5
ImPulSive ImPulSive is online now
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Quote:
Originally Posted by GeneticMutation View Post
I have had a little play on this but not sure if I'm using it correctly

The longest part of my room is about 11 feet (I'll post correct measurements when I get home) which projector would you recommend? It'll be in a living room with a large EAST facing window but the projector will mostly be used in the evenings for blu ray movies, SKY HD and a little PS3 gaming.

We rarely watch TV during the day as we both work and at weekends are always busy or out visiting!

EDIT: I've been looking primarily at Epson projectors as they seem to get the most amount of praise over on AVForums!
I will let others chime in with their recommendations. Yes, Epson does make good PJs, but that all depends on who you ask and what you need the PJ to do for you.

Things to factor in:
- do you have 100% light control, or something less? Can you fix that via black out curtains?
- colors of the walls, and ceiling? Darker matte is better for PJ but may not work well with the significant other. If too light, may be issues with reflections, reducing contrast.
- can you place the PJ in the dead center sweet spot? If not, make sure to get a PJ that has lens shift to make placement easier. Not all do.
- want 3D? If so, make sure PJ is bright enough, you lose light via glasses so you need brighter PJ. If not, might be able to compensate via screen gain of 1.3 or 1.4 or similar.
- black levels? How big of an issue is this for you? Some people are very picky, others not so much.

I have an Epson 8700UB PJ and I love it. Great black levels, but not the brightest PJ. Works very well in 100% light controlled room with 126 inch 1.78 screen with 1.4 gain and 17 feet from the screen. Lets me use it in eco mode for less noise, longer bulb life, and then use full power for extra punch when needed. Can still get them as refurbs.

Or perhaps you want 3D in which case look at the Epson 5020 series. Panasonic also has good gear too. I have the AE7000 for 3D, but if I was to buy today I would get the AE8000. Big Daddy has one, search for his review.

Not sure about the model # where you live, these are in the US.
Power: APC H15 Conditioner, CyberPower CP1350PFCLCD Pure Sinewave UPS w PFC (for PJ, PS3)
Pre/Pro: Onkyo TX-NR808 Amps: Emotiva XPA-3 Gen2 (200W x 3) XPA-5 Gen2 (200W x 5)
Speakers: Def Tech BP8B (Front L+R), Pro Center 2000, Pro Monitor 1000 x 4 Subs: SuperCube 2000 x 2, ProSub 1000 x 2
Screen: Carada Precision 126 inch 1.78 BW Fixed Frame PJ: Epson 8700UB (2D) Panasonic AE7000U (3D)
Player: PS3, Mac-Mini Video Acc: MonoPrice 1x2 HDMI Splitter w/3D Support, Darbee DVP5000 Darblett
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Old 02-01-2013, 04:26 PM   #6
kpkelley kpkelley is offline
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Quote:
Originally Posted by ImPulSive View Post
Things to factor in:
- do you have 100% light control, or something less? Can you fix that via black out curtains?
- colors of the walls, and ceiling? Darker matte is better for PJ but may not work well with the significant other. If too light, may be issues with reflections, reducing contrast.
- can you place the PJ in the dead center sweet spot? If not, make sure to get a PJ that has lens shift to make placement easier. Not all do.
- want 3D? If so, make sure PJ is bright enough, you lose light via glasses so you need brighter PJ. If not, might be able to compensate via screen gain of 1.3 or 1.4 or similar.
- black levels? How big of an issue is this for you? Some people are very picky, others not so much.
You missed a few:

-how will the projector be mounted? How will this affect the screen size given the height of the walls and viewing angles.
-what aspect ratio will the screen be?
-Budget
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Old 02-01-2013, 05:34 PM   #7
GeneticMutation GeneticMutation is offline
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Ok a few questions there lets see if I can answer all them for you guys:

Lighting - Large east facing window very bright room during the day but can get it very dark in the evenings.

Wall colour - This can be changed easily and we're looking at some dark colours for the viewing wall and a lighter shade of that for the rest of the room.

Sweet spot / mounting - This is easy as there is nothing in the way and it'll be ceiling mounted so its out the way and can be placed anywhere.

3D - Not to bothered about this as I don't think it'll last long on the consumer market (we'll see).

Black level - This is something I would really like but I'm no expert and not sure I would notice it as much as some of you guys. I would get the PJ professionally calibrated once all installed if that helps?

Aspect ratio - 16:9 as the PJ will be used primarily for blu rays and some PS3.

Budget - 1-1.5k solely for the PJ.

Hope I've answered all questions asked and they make sense!
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Last edited by GeneticMutation; 02-01-2013 at 06:15 PM.
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Old 02-01-2013, 06:38 PM   #8
kpkelley kpkelley is offline
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The two epson projectors are probably your best bet, the TW3200(800Gbp) and TW6000(1800Gbp). You may be able to find a TW5900 still, which imo would be better than the TW3200 and cost much less than the TW6000.

The Sony's and JVCs are outside of your budget from everything I could find over the pond. Some people prefer DLPs to 3LCD projectors, so perhaps a projector from BenQ or Mitsubishi. These however usually come with some limitations in terms of lens shift.

An interesting prospect would be the ViewSonic Pro 9000 Laser Hybrid LED Projector(1600Gbp), but I've never seen any of the laser based projectors in person. This projector has no lens shift, though, so strict measurements would need to be taken to ensure that it would work within the space. Here's another review on that one.
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Old 02-01-2013, 06:58 PM   #9
GeneticMutation GeneticMutation is offline
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I have my room measurements if that makes a difference?

Height - 7' 4"
Length - 12' 10"
Width - 12'

What do you think to this:

Epson EH-TW6100
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Old 02-01-2013, 07:15 PM   #10
kpkelley kpkelley is offline
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Quote:
Originally Posted by GeneticMutation View Post
I have my room measurements if that makes a difference?

Height - 7' 4"
Length - 12' 10"
Width - 12'

What do you think to this:

Epson EH-TW6100
The 6100 is the model which replaces the 6000. I didn't realize it was available over there yet. That seems like a good value.

At that height, a projector without lens shift wouldn't make any sense if you were ceiling mounting the projector, it would force a smaller screen size than you would probably like. Seems like the Epson would be the best choice.

Assuming that it's similar to the tw6000, a screen just north of 100" seems like a good size, though as small as 92" would be within the 2.5-3x image height([distance from seating position to screen in inches]/[2.5 or 3]=image height, resulting in a range of diagonal size from 90" up to 108"). If the projector were shelf mounted(i.e. mounted against the back wall), then you could go as large as about 120".
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Old 02-04-2013, 10:34 AM   #11
GeneticMutation GeneticMutation is offline
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Quote:
Originally Posted by kpkelley View Post
The 6100 is the model which replaces the 6000. I didn't realize it was available over there yet. That seems like a good value.

At that height, a projector without lens shift wouldn't make any sense if you were ceiling mounting the projector, it would force a smaller screen size than you would probably like. Seems like the Epson would be the best choice.

Assuming that it's similar to the tw6000, a screen just north of 100" seems like a good size, though as small as 92" would be within the 2.5-3x image height([distance from seating position to screen in inches]/[2.5 or 3]=image height, resulting in a range of diagonal size from 90" up to 108"). If the projector were shelf mounted(i.e. mounted against the back wall), then you could go as large as about 120".
Yeah I was thinking of ceiling mounting as it's the easiest place to put it in the room!

So does the projector have to point at the top of the screen when mounted, also will this reduce the need for screen correction?
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Last edited by GeneticMutation; 02-04-2013 at 12:43 PM.
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Old 02-04-2013, 05:29 PM   #12
ZoetMB ZoetMB is offline
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There are calculators online, but the formula is this and if you know basic algebra, you can handle it:

FW=DA
where F = focal length of the lens in inches.
W= Width of the screen in feet
D= Distance from the screen in feet
A=Aperture of the projector in inches.

So:
If you're trying to find the right lens:
F = DA/W
Distance = 20', Aperture=1" (don't know what your aperture is, this is just an example), Width of screen = 12'
F = (20 x 1)/12
F = 20/12
F = 1.67" (of course if you have a zoom, this won't matter much).


If you're trying to find the right sized screen:
W=DA/F
Distance = 20', Aperture = 1", Focal length = 2"
W = (20 x 1)/2
W = 20/2
W = 10 feet.
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Old 02-05-2013, 12:13 PM   #13
GeneticMutation GeneticMutation is offline
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Quote:
Originally Posted by ZoetMB View Post
There are calculators online, but the formula is this and if you know basic algebra, you can handle it:

FW=DA
where F = focal length of the lens in inches.
W= Width of the screen in feet
D= Distance from the screen in feet
A=Aperture of the projector in inches.

So:
If you're trying to find the right lens:
F = DA/W
Distance = 20', Aperture=1" (don't know what your aperture is, this is just an example), Width of screen = 12'
F = (20 x 1)/12
F = 20/12
F = 1.67" (of course if you have a zoom, this won't matter much).


If you're trying to find the right sized screen:
W=DA/F
Distance = 20', Aperture = 1", Focal length = 2"
W = (20 x 1)/2
W = 20/2
W = 10 feet.
This all just became really confussing!!!
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