I'm most likely going to get an 4805. It will be mounted approx. 2-3 ft. above the sitting position. Will the gain drop significantly, like it would if mounted to the ceiling, or with it only a couple of feet above be worth the additional cost for the additional gain?
High Power question
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If the lens is within 4 feet of your eye, you are in the cone of the highest gain. At two to three feet, you'll probably get a gain of 3.0 on the High Power. Also, the drop off is so gradual that very few notice it. But if you try really really hard, you can kind of see it.
Take a look at this thread: http://www.avsforum.com/avs-vb/showt...e&pagenumber=1
Sorry, bad link. Try this one: http://www.avsforum.com/avs-vb/show...ighlight=JHouse
I would have to completely disagree. I think it all boils down to your setup in the end, but there's no way I was seeing a 3.0 gain or near itr with my head 2-3 feet away from the pj. The difference is VERY noticeable to me just by moving a few feet up/dwn. I would never recommend the high power for a ceiling mount unless your projector is literally just about your couch.
Save your money, get Pearl, or VS from da-lite ( if your dead set on getting a da-lite) at 1 third the cost, and you'll have more gain at seating level with a ceiling mount then the hp ever would. Granted, the HP has other advantages, it's thick, very durable, no sparkly problem, but it's cost for me is just a no no for a ceiling mount. The higher the celing the more useless it should be. If I get time the weekend, I'll take my own pics at seating level, and ceiling level
Save your money, get Pearl, or VS from da-lite ( if your dead set on getting a da-lite) at 1 third the cost, and you'll have more gain at seating level with a ceiling mount then the hp ever would. Granted, the HP has other advantages, it's thick, very durable, no sparkly problem, but it's cost for me is just a no no for a ceiling mount. The higher the celing the more useless it should be. If I get time the weekend, I'll take my own pics at seating level, and ceiling level
I used to have a measly 1.3 gain screen. It had hot-spotting that was relatively less noticeable than my 70" Mitsubishi RPTV, but still noticeable. The High Power eliminated that. It has ambient rejecting properties that are pretty decent also. Lots of pretty smart guys on this forum have the High Power in a ceiling mount location. As I recall Tryg's measurements, if you get your face right next to the projector, the gain goes over the 2.8 spec. If you draw it out, as in the thread above, it isn't that hard to have your eyes in the 25 degree cone of highest gain. But the beauty of the screen is how gradually and inoffensively the gain drops off. I have found that if you stay in the 10 foot area in front of the screen, you still get what appears to be most of the gain. You certainly don't miss what you are losing. About the only way to see the fall off in gain is to move very quickly side to side or up and down. And it's still hard to see. At least this is my experience. Maybe some have something like "perfect pitch" to ft.L. and can easily see the differences. I can't. And that has been the experience of my friends and family.
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"I would have to completely disagree. I think it all boils down to your setup in the end, but there's no way I was seeing a 3.0 gain or near itr with my head 2-3 feet away from the pj. The difference is VERY noticeable to me just by moving a few feet up/dwn. I would never recommend the high power for a ceiling mount unless your projector is literally just about your couch."
I completely agree with newfmp3! The picture quality is good with the HP but the cone is way to narrow for me. It drove me nuts that when i was standing the picture was awesome but sit down and half the brightness was gone...and that was only a shift of 3 or 4 feet at 15 feet from the screen. I have a Draper M2500 and sitting down the draper was brighter. The Draper doesn't drop off as you walk around the room at 15 feet back. The HP fluctuated all over the place.
Just my opinion...everyone should judge for themselves. Some may not be bothered by the small cone.
Ron
"I would have to completely disagree. I think it all boils down to your setup in the end, but there's no way I was seeing a 3.0 gain or near itr with my head 2-3 feet away from the pj. The difference is VERY noticeable to me just by moving a few feet up/dwn. I would never recommend the high power for a ceiling mount unless your projector is literally just about your couch."
I completely agree with newfmp3! The picture quality is good with the HP but the cone is way to narrow for me. It drove me nuts that when i was standing the picture was awesome but sit down and half the brightness was gone...and that was only a shift of 3 or 4 feet at 15 feet from the screen. I have a Draper M2500 and sitting down the draper was brighter. The Draper doesn't drop off as you walk around the room at 15 feet back. The HP fluctuated all over the place.
Just my opinion...everyone should judge for themselves. Some may not be bothered by the small cone.
Ron
I wish the high power did work out for me as it was the best material of the da-lite that I have seen.
Each setup is different. I'm surprised that there isn't a sticky in this section that says GET SAMPLES 1ST, then start asking questions. You really do need to see things for yourself in your setup, and getting samples is the only logical first step.
Each setup is different. I'm surprised that there isn't a sticky in this section that says GET SAMPLES 1ST, then start asking questions. You really do need to see things for yourself in your setup, and getting samples is the only logical first step.
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I have been using the Hi Power with a ceiling mounted Pana300 for two years now. My projector is about 3 - 4 feet from my head in the sitting position. When standing up, I estimate the picture is only about 10% brighter. Of course, that is my best estimate without any measuring equipment.
Before I bought the Hi Power, I went through the same agonizing process of wondering how much I would lose with a ceiling mounted projector. After I got the screen and set it up, I thought I had been silly agonizing over nothing.
Hope that helps.
River
Before I bought the Hi Power, I went through the same agonizing process of wondering how much I would lose with a ceiling mounted projector. After I got the screen and set it up, I thought I had been silly agonizing over nothing.
Hope that helps.
River
gx270 --- You have me puzzled. I just finished looking at the 4805 Users Guide and it looks like the PJ should be on a shelf at about the same height as your head. Putting the PJ at 2 - 3 feet abouve your head would put the bottom of the screen at 3 - 5 feet above your head (depends on screen size). This means that you would be looking up at the screen (neck strain - big time). Also it would mean that you must have very high ceilings or plan on getting a very small screen.
In my living room with a 8.5 foot ceiling, the top of my Da-Lite Hi-Power (Model C pull-down) screen is about 10.5 inches below the ceiling (that's about as high as I can mount it (See my post #17 on the "Panasonic PT-300U users??" thread for a picture). My screen is a 106" diagonal, (92" wide x 52" high). The bottom of my screen is about 4' from the floor (about a foot above my seated head) and my PJ (Panny L300U) is about a foot above my head. The 4805 has a bigger offset than my L300, which would put it at just about head height on the shelf behind our seating position. I certainly would not want the screen to be much higher.
In my living room with a 8.5 foot ceiling, the top of my Da-Lite Hi-Power (Model C pull-down) screen is about 10.5 inches below the ceiling (that's about as high as I can mount it (See my post #17 on the "Panasonic PT-300U users??" thread for a picture). My screen is a 106" diagonal, (92" wide x 52" high). The bottom of my screen is about 4' from the floor (about a foot above my seated head) and my PJ (Panny L300U) is about a foot above my head. The 4805 has a bigger offset than my L300, which would put it at just about head height on the shelf behind our seating position. I certainly would not want the screen to be much higher.
Question for JHouse:
I'm considering the High Power, and one statement you made above intrigued me: "It has ambient rejecting properties that are pretty decent also." This issue is of prime importance to me. While ambient light sources can be well-controlled, my room has light-colored floor, walls and ceiling, so I'd really like to minimize light from the screen hitting those surfaces and then reflecting back to the screen. I just bought my first PJ yesterday(a 7205), and putting samples from Da-Lite and Carada over our current screen(a bare, off-white wall), I noticed that while black level was elevated with the High Power compared to the others, the white level was elevated more, which seems like a good thing. Now, if the retro-reflectivity of the screen could reduce light reflecting back from the walls, etc., that would be icing on the cake. Do you think black levels would improve with the High Power because of this?
If so, the only down side I can see to the High Power is that, due to a funky arrangement in the room, my wife would be about 4' offaxis @ 15 feet from the screen. Readings with a spot meter confirmed that brightness from there would be about 35-40% reduced from 2' offaxis.
Thanks,
Jeff
I'm considering the High Power, and one statement you made above intrigued me: "It has ambient rejecting properties that are pretty decent also." This issue is of prime importance to me. While ambient light sources can be well-controlled, my room has light-colored floor, walls and ceiling, so I'd really like to minimize light from the screen hitting those surfaces and then reflecting back to the screen. I just bought my first PJ yesterday(a 7205), and putting samples from Da-Lite and Carada over our current screen(a bare, off-white wall), I noticed that while black level was elevated with the High Power compared to the others, the white level was elevated more, which seems like a good thing. Now, if the retro-reflectivity of the screen could reduce light reflecting back from the walls, etc., that would be icing on the cake. Do you think black levels would improve with the High Power because of this?
If so, the only down side I can see to the High Power is that, due to a funky arrangement in the room, my wife would be about 4' offaxis @ 15 feet from the screen. Readings with a spot meter confirmed that brightness from there would be about 35-40% reduced from 2' offaxis.
Thanks,
Jeff
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If the 4805 is going to be upside down all this is flipped.
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Any screen that has a lot of directionality (high gain to one spot) will help ANSI CR (reduce washout from reflections) if you are in a high gain position for the projected light, but not for the average of the reflections around the room. And if you are outside the viewing cone (at a low gain position) then the effect is the opposite. That is, it can make the washout from reflections worse. It all has to do with getting better gain from the projected image than from the reflections. Like if you are sitting at a 2.0 gain position, but the average gain for reflections around the room, then back to the screen and to you is 1.0, this is a good thing. If you are sitting at a 0.6 gain position for the projected light, that is a bad thing as far as ANSI CR.
In answer to your question, the perceived black levels in mixed images could be better because of this. However, since no screen can treat 100 IRE different than 0 (or 7.5) IRE, your absolute blacks in very dark images will be brighter if you are sitting in a position where your whites are brighter (a greater than 1.0 viewing position).
One rule to remember is that white and black always get the same gain (assuming same color mix). There is no magic screen out there that knows you want black and has lower gain for that. If there was, we wouldn't have to worry about what CRs our projectors can do.
--Darin
| Originally posted by CT_Wiebe gx270 --- You have me puzzled. I just finished looking at the 4805 Users Guide and it looks like the PJ should be on a shelf at about the same height as your head. Putting the PJ at 2 - 3 feet abouve your head would put the bottom of the screen at 3 - 5 feet above your head (depends on screen size). This means that you would be looking up at the screen (neck strain - big time). Also it would mean that you must have very high ceilings or plan on getting a very small screen. |
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| Originally posted by astroboy Do you think black levels would improve with the High Power because of this? |
In answer to your question, the perceived black levels in mixed images could be better because of this. However, since no screen can treat 100 IRE different than 0 (or 7.5) IRE, your absolute blacks in very dark images will be brighter if you are sitting in a position where your whites are brighter (a greater than 1.0 viewing position).
One rule to remember is that white and black always get the same gain (assuming same color mix). There is no magic screen out there that knows you want black and has lower gain for that. If there was, we wouldn't have to worry about what CRs our projectors can do.
--Darin
I found another disadvantage of the high power it seems. While trying to get a piece of dirt off, I hit it with my finger nail, and it seems the surface scratches very easy. In fact, you can indeed scratch the paint off so to speak with just your finger nail.
It's the only surface of all the materials I have that does this.
It's the only surface of all the materials I have that does this.
Astro, I have the same set up as you. Bright walls and ceiling. I've never measured anything, but my High Power was a HUGE improvement over a 1.3 gain screen from the same manufacturer. If you think about what Darin said, if light surfaces add to your problem, it would seem that keeping as much light hitting you in the face instead of going back to the walls might be even more important in a bright room. I guess that's one reason why it works to well for me.
Rverplace, that has been exactly my experience too.
One more tip. Mount your High Power as low as possible in a ceiling mount set up. That will get your head more in between the lens and most of the screen.
Rverplace, that has been exactly my experience too.
One more tip. Mount your High Power as low as possible in a ceiling mount set up. That will get your head more in between the lens and most of the screen.
Thanks, Darin and Joe. I don't mind absolute black level being relatively high, as that gives me an excuse to rig some sort of iris and improve contrast further. And even 4.5 feet off axis, I measured 25-30% more light from the High Power than from the wall itself, or from two "1.0 gain" screen samples. So I guess that would still be better than nothing. The problem remains of the differential between the prime seating location and the one 4.5' off-axis. The person sitting in the prime spot will look and say "Hey, we've got excess light here, this is giving me a headache. Let's stop this puppy down and make it look even better," while the other person is saying "Whoa, now it's too dark."
Jeff
Jeff
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