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Discussion Starter · #1 ·
I have finally decided to get a screen for my G11, currently thinking of a firehawk 16:9, 107"x60", mostly for dvd viewing.

Depending on the zoom at the pj, my mounting distance will obviously change. The pj can be mounted anywhere from 17' to 25'.

My question is - are there any advantages to projecting without any zooming as opposed to full zooming in terms of distortion or any other effects.

Also, would the brightness be affected since while using dilard, the degree of zooming seems to alter the brightness values.

Thanks in advance,

Sanjiv
 

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Quote:
Originally posted by sprakash


Also, would the brightness be affected since while using dilard, the degree of zooming seems to alter the brightness values.

Thanks in advance,

Sanjiv
I assume you mean that zooming seems to alter the perceived brightness value. It shouldn't actually affect any real brightness settings in the projector.


Since all of the optics involved at different zoom levels are the same, there is no actual change in the total amount of light from the projector to the screen. However, as the actual projected image itself gets larger and smaller, you definitely will see a change in the image brightness, simply because there is a change in the total amount of light available divided by the number of square inches of image. This is essentially the benefit of using the panamorph lens to view 16:9 images with a 4:3 panel.


As far as where to mount your projector, I would install it such that the largest image (zoomed out?) produced is just a little bit larger than your desired screen size. This will give the most amount of "useable" zoom. You may find that you'll want to zoom-in when viewing poorer quality signals (VCR, NTSC).


Technically speaking, the measured light intensity drops off at an exponential rate in relation to the distance. In other words, the closer to the screen, the better.
 

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I don't agree taht the closer to the screen the better with Sharp 9000. I am using 16x9 96 inch firehawk and have pj at max distance with no zoom When pj is at min distance and zoomed to fit screen the loss of overall brightness is very noticable and overall geometry is is incorrect. I initally thought that the closer the better but it did not take too many position swaps to prove that the the max distance with no zoom is far better.
 

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Discussion Starter · #5 ·
Hi Harvey,

that was my theory too. Maybe I need to physically move the pj and test it out.

What dvds did you use for checking the geometry? I could try VE. Any particular chapter/scene you could guide me to would help.

Thanks,

Sanjiv
 
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