BMXTRIX.......or other experienced Projector people

[zipper]

I want to make a move to a FP in the future & have a few questions. I've been reading a lot at Projector Central & here. While I've gathered lots of info, a couple things are still a bit vague.

1. Is it better to be in the middle of the "throw range" of a projector or is it preferable not to use the zoom at all? Or does it not matter? My room is 15'4" across with a vaulted ceiling sloping from the middle of the house down to an outside wall..........ceiling mount is out. However, there is about a 14" ledge above the middle wall (couch sits against that wall facing the outside wall where I would have my screen) which is 8'4" high..........it has about 30" of vertical clearance to the peak. I could easily set the proj up there.........there's a closet below so wiring would be no problem. I've seen that you like the Panny AX100U for it's flexibility & I've looked that over on the Proj. Cent. site with the calculator. When I put in my throw distance it takes me down to a 75" screen. When I put in my preferred screen size (about 100") it backs up to a bit over 20'..............putting my throw distance in about the middle of its range. Is that cool? I currently have a 55" Mitsubishi RP-CRT & don't want to go to a projector unless I can go much bigger. BTW, my viewing distance is approx. 13' 6" or 162", with my eyes at about 42" from the floor.

2. I'm also curious about the native pitch angle of the projector............if there is one. I figure if I have the projector placed as mentioned the lens will be at about a height of 106" above the floor. Allowing for a little leeway, the center of my 100" screen would be about 66" above the floor, 15' away. Is this going to require much lens shift? I've looked at the Mitsubishi HD1000U, which has no lens shift, & was curious about how one would mount that to center it on the screen. Would it have to be level with the center of the screen or does it have a pitch/shift built in? Doesn't seem like it would be very user/installer friendly if it didn't.

3. Screen gain............I don't have the best room for light control at the moment (one of the reasons I'm looking at the Panny, per your remarks in another thread) but it could be bettered. The PC calculator suggests a screen gain of 1.5, but I've read somewhere that a lot of gain can cause other issues, i.e. sparkling. True? Or not really an issue?

All thoughts/advice are appreciated. I'd love to do this but want to make sure I'm not going to have any surprises.........or at least understand what I'm up against.

Thanks in advance.........

 

[BMXTRIX]

I tend to think that using around the middle of the zoom range of any projector is best. You get to far to either extreme and you can start to have some lens issues which can degrade the image. In a perfect world with perfect lens design, you would never have this, but in the real world, it is something that concerns me a bit.

Keep in mind a 'zoom' lens is always zoomed to something. You either zoom all the way in, or you zoom all the way out, or you zoom somewhere in between. So, you can't ask if it is better or worse to use zoom - because you will always have to use it when you have a zoom lens. My recommendation is that you simply try to avoid extremes.

For lens shift, the neutral position of the lens is near the center of the screen, but you have a lot of room with that projector and on the high/low end you can typically have the projector several inches above the top of the screen. That's center of lens to top of the screen - perhaps 6 inches or so, without needing to tilt the projector at all.

You're confusing me a bit on the throw range thing... With a 100" diagonal (which is small from 13' viewing) you can put the projector anywhere from 10 to 20 feet from the screen. That's the whole point of the zoom lens. Please understand, that I think DLP produces a better image overall than LCD when it comes to black levels and shadow detail, but the cheaper DLP projectors have pretty strict setups required to get the best out of them. That is, if you can place the projector about 18" above a 100" diagonal screen and have it so the lens is 12 to 15.5 feet from the screen, than a projector like the Mits. HD1000 or the Optoma HD70 will work from about 11.5 to 14 feet.

As far as screens go... I have only seen sparkling in total junk screens. A decent screen, like the Carada Brilliant White screen will deliver 1.4 gain without causing negative image quality issues. Don't go cheap here and you won't have issues.

FYI: Had you asked on Projector Central's forums you would have gotten a pretty good answer I expect - I hear that AV_Integrated guy knows his stuff.

 

[mtrycrafts]

I want to make a move to a FP in the future & have a few questions. I've been reading a lot at Projector Central & here. While I've gathered lots of info, a couple things are still a bit vague.

1. Is it better to be in the middle of the "throw range" of a projector or is it preferable not to use the zoom at all? Or does it not matter? My room is 15'4" across with a vaulted ceiling sloping from the middle of the house down to an outside wall..........ceiling mount is out. However, there is about a 14" ledge above the middle wall (couch sits against that wall facing the outside wall where I would have my screen) which is 8'4" high..........it has about 30" of vertical clearance to the peak. I could easily set the proj up there.........there's a closet below so wiring would be no problem. I've seen that you like the Panny AX100U for it's flexibility & I've looked that over on the Proj. Cent. site with the calculator. When I put in my throw distance it takes me down to a 75" screen. When I put in my preferred screen size (about 100") it backs up to a bit over 20'..............putting my throw distance in about the middle of its range. Is that cool? I currently have a 55" Mitsubishi RP-CRT & don't want to go to a projector unless I can go much bigger. BTW, my viewing distance is approx. 13' 6" or 162", with my eyes at about 42" from the floor.

2. I'm also curious about the native pitch angle of the projector............if there is one. I figure if I have the projector placed as mentioned the lens will be at about a height of 106" above the floor. Allowing for a little leeway, the center of my 100" screen would be about 66" above the floor, 15' away. Is this going to require much lens shift? I've looked at the Mitsubishi HD1000U, which has no lens shift, & was curious about how one would mount that to center it on the screen. Would it have to be level with the center of the screen or does it have a pitch/shift built in? Doesn't seem like it would be very user/installer friendly if it didn't.

3. Screen gain............I don't have the best room for light control at the moment (one of the reasons I'm looking at the Panny, per your remarks in another thread) but it could be bettered. The PC calculator suggests a screen gain of 1.5, but I've read somewhere that a lot of gain can cause other issues, i.e. sparkling. True? Or not really an issue?

All thoughts/advice are appreciated. I'd love to do this but want to make sure I'm not going to have any surprises.........or at least understand what I'm up against.

Thanks in advance.........

My suggestion would be to try closer to the minimum throw distance. Also, check out the projector book on line for details how far away from walls to mount it for ventilation reasons. Some have the hot air blown out the back.

Also, try to get the largest screen for the sitting distance. There is nothing like a big screen and big sound

 

[BMXTRIX]

My suggestion would be to try closer to the minimum throw distance.

While this may sound good, you actually end up creating a less even image on screen for light levels due to the wider angle of incidence between the projector and the screen. The further back you can put a projector is generally accepted as being better for producing a more uniform image on screen, but because of current lens designs and price factors, you usually have aperatures that close down at longer ranges. Include possible optical distortions near any extreme of zoom range and it seems to me (opinion) that the best compromise is just somewhere in the middle of the range.

Also, check out the projector book on line for details how far away from walls to mount it for ventilation reasons. Some have the hot air blown out the back.

This is always good advice, but in the case of the AX100U the design puts air flow entirely on the front of the projector so it can be shelf mounted against a wall at the back of the room if necessary.

Also, try to get the largest screen for the sitting distance. There is nothing like a big screen and big sound

Absolutely not!

...or maybe...

The screen size really should be a very careful consideration that takes into account many factors including personal viewing preferences, the material that will be used, the resolution of the projector, and where your family likes to sit in a movie theater. Simply 'going big' may actually produce results that overwhelm people in the room and the room itself. A screen that is to big can actually create a tennis game effect where viewers actually have to move their head back and forth to just keep track of what is going on screen. It also increases the size of any flaws in the source material.

A good rule is to follow THX standards which is what most movie theaters use: Take your primary seating distance, multiply it by .66 and that should be the width of your screen. Generally speaking, this will give very positive results for most people.

ON THE OTHER HAND: In my experience, most people go a bit on the 'small' side when doing their setup. I recently installed a setup with a AX100 on a 160" diagonal Carada 1.4 BW screen and while a bit overwhelming for the width of the room, it is appropriately sized for the rear row of seating in the room. The owners are very happy.

 

[zipper]

Thanks for the replies gentlemen. Didn't even think about the heat factor mtry.........thanks for mentioning it.
I didn't notice that Proj. Cent. HAD a forum. I guess I'll check it out now that I know.
As far as viewing distance, I was going by the "1.5X the screen size for viewing distance" formula to calculate what would work for me. I like your formula better BMX .

......but the cheaper DLP projectors have pretty strict setups required to get the best out of them. That is, if you can place the projector about 18" above a 100" diagonal screen and have it so the lens is 12 to 15.5 feet from the screen, than a projector like the Mits. HD1000 or the Optoma HD70 will work from about 11.5 to 14 feet.

So if I understand you correctly, the Mitsu. IS an option with the room setup I mentioned? That is, if I go with a bit bigger screen & move it down the wall a bit? Going to a 110" screen brings the Mitsu. throw range out to 13-16 ft.......putting it in my range. I'm curious because the $$ saved by getting that unit would just about pay for the Carada screen you suggested. I'm don't want to cheap-out on this but $ is $ & they appear to be comparable units.

 

[mtrycrafts]

Thanks for the replies gentlemen. Didn't even think about the heat factor mtry.........thanks for mentioning it.

As far as viewing distance, I was going by the "1.5X the screen size for viewing distance" formula to calculate what would work for me. I like your formula better BMX .

.

Yes, exhaust can be sucked back in, certainly projector dependent, and it will overheat, shorten bulb life and increase vent speed that may be objectionably loud.

Your 1.5X and his .66 is equivalents: 1:1.5=.66 so his is one way, your is another way with same results.

 

[BMXTRIX]

Yeah, if the numbers work for your setup, then you can go with the Mits instead of the Panny and should have great results. Please understand that the Mits MUST be mounted upside down at that height. So, it can't 'sit' on a shelf at 8 or 9 feet, but must be ceiling mounted, or buid a shelf that it can mount on the underside of.

Also, I'm not sure what the ventilation is like for the Mits., so that is something that you will want to check out for sure.

I know that in my house my screen only has 12" of black drop (motorized) and these darn DLP projectors with no lens shift are just useless from my home because I refuse to tilt them to compensate.

I think I'm going to upgrade our plasma before I do the projector anyway.

Anyone got $3 grand or so? I want a Pioneer 60"er!

 

[zipper]

Thanks again............I'm not going to jump on this tomorrow but want to be ready when I do.

Appreciate the help fellas.......

 

[mtrycrafts]

Thanks again............I'm not going to jump on this tomorrow but want to be ready when I do.

Appreciate the help fellas.......

Hey, pre planning is the way to go Take your time, find out as much as you possibly can and then go for it.

Also, a consideration, is that 1080p hi def DVDs are here and they will stay. You may want that to be in the plans as well?