[qopit]

Quick question...


Is there any image drawback or penalty when you use a projector's zoom feature?


ie: is it better to lock the projector zoom at 1x (no zoom) and match the projector distance to fit the screen size you've chosen, or is it fine to tweak the distance to fit your room by playing with the zoom?

 

[Gray Davis]

"Is there any image drawback or penalty when you use a projector's zoom feature?"


I think this has been debated here before, and as far as I know the conclusion is that it does not matter.

 

[Horst]

A german site just published a comparison using the zoom settings on diffrent projectors.

They found that you can realize a higher contrast ratio in the loner throw setting of the zoom.

They speculate that in this setting the light path is narrower (essentially giving you a similar benefit as an Iris).


You can find their report at: www.peterfinzel.de/tuning.htm


Regards,


Horst

 

[jayw]

Hmmm. 2 1/2 years of German but 25 years ago. So I resorted to using babelfish. Go to http://babelfish.altavista.com/ and put in that URL www.peterfinzel.de/tuning.htm . Then tell it to do a German->English translation. Perfectly readable but not perfect. Pretty interesting test. I wouldn't have thought it would make a difference.


JayW

 

[qopit]

Interesting... thanks for the german link (and the babelfish link). I think my favorite part of the translation was "which caused first only head vibrating and confirmed my reservations apparently"


In the summary at the end it sounds like he's saying his measurements only showed a difference for low end DLP projectors and not LCD? Hard to tell...


Anyway - I'm content with the fact that there doesn't seem to be a major impact. Thanks again.

 

[GreggPenn]

The other difference that has been reported is light uniformity. And the longer (narrower) beam a PJ throws, the more uniform the light will be out to the edges of the picture. Again, this is a small thing (just like contrast improvements).

 

[Ian Fleet]

I originally put my projector as far back as it could go with the zoom at maximum. I later mounted my projector as close as I could with the zoom at minimum.

I had a better picture quality up close because of lumens. As the projector is further away the picture is darker and not as sharp.

My projector puts out 1000 lumens.

Projector lenses are quite good so if you have a projector with alot of lumens you can go further back.

 

[snocrash]

Zoom is bad - Laws of physics dictate this - Different wavelengths of light refract through interfaces differently.


This topic has been discussed to death -- have a read of an old post of mine: http://www.avsforum.com/avs-vb/showt...37#post1721537