Jump to content



Photo
- - - - -

Choose projector by throw ratio


  • You cannot start a new topic
  • Please log in to reply
6 replies to this topic

#1 of 7 JasonWynia

JasonWynia

    Member

  • PipPip
  • 28 posts
  • Join Date: Nov 11 2003

Posted May 10 2005 - 10:58 AM

In the last couple of weeks, I picked up an Infocus 4800 when Woot.com had their incredible deal. I just couldn't pass it up and bought it, not sure whether I could use it or not.

Well, it turns out that I really can't (unless a crazy modification can solve my problem). I'll be putting it up for sale and looking for a better solution for my particular needs.

Here it is in a nutshell. My current setup includes a 52" rear projection HDTV. My eventual intentions have been to have a screen come down from the ceiling for front projection in front of my existing TV and speakers. I've got about 10 feet from the screen/tv plane to the seating.

The 4800 can only throw about a 50" wide image at that distance (my HDTV is already 45" wide or so). For THX viewing angles, etc. (which I've subsequently looked up and figured out what I really want) I need to be able to get a 78" image at a 10' throw. So, I'm looking for either recommendations or a way to filter through all of the available options and find those that meet this one criteria.

The 4800 has a really nice picture, options, etc. and worked well at the sizes I was able to test (it's now got 2 hours on the bulb), but doesn't have the ability to throw an image big enough to make it wortwhile over my existing rear projection setup and the THX numbers will do that if I can find a projector that will handle it.
J Wynia
(please call me J)

#2 of 7 Jim Mcc

Jim Mcc

    Advanced Member

  • PipPipPip
  • 3,710 posts
  • Join Date: Feb 11 2004
  • Real Name:Jim
  • LocationOconomowoc, WI.

Posted May 10 2005 - 12:34 PM

According to the calculator at Projectorcentral.com, you can get an image size from 62"-74" diagonal, using a 10' throw. It's too bad you didn't check this out first. I have the same projector(X1) and I love it. I had a 55" Mitsubishi
widescreen and sold it because we hardly used it anymore, since we bought the X1. We bought a 32" analog set to watch BS TV shows with. I would sell the RPTV before the 4800.

#3 of 7 JasonWynia

JasonWynia

    Member

  • PipPip
  • 28 posts
  • Join Date: Nov 11 2003

Posted May 10 2005 - 01:11 PM

Because of the way Woot.com works, there really isn't a chance to "check anything out". They only sell 1 product per day and when they're gone, they're gone. Most products are gone before 10:00 am. I happened to notice the 4800 for sale at 3:45pm and it was only $499. Even if I didn't keep it, it was a good enough deal that I'd easily be able to sell it and move on.

My numbers weren't exact. I should have double checked them before posting.

It's currently set up on the other side of the basement for testing purposes. At 100", it's throwing a 55x33 16:9 image. I just used the ProjectorCentral calculator (thanks for that info) and I'd need a throw of 12.2' to get the desired 78" wide image (not diagonal). That's over 2 feet more than I have. The best the calculator says I can do at 10' is a 65" wide screen. I wasn't really planning on buying a projector this year at all, but it was an incredible deal. However, the project I had envisioned for next year (before this deal came along) was full THX ratios with the TV as a backup for satellite programming and easier daytime viewing. Had this projector come closer to that goal, I'd definitely be keeping it, but it just falls too far short.
J Wynia
(please call me J)

#4 of 7 Jim Mcc

Jim Mcc

    Advanced Member

  • PipPipPip
  • 3,710 posts
  • Join Date: Feb 11 2004
  • Real Name:Jim
  • LocationOconomowoc, WI.

Posted May 10 2005 - 06:08 PM

J, something is wrong here. Are you using the zoom on the projector? The calculator shows an image size of 62"-74" diagonal, 16:9, from 10'.

#5 of 7 JasonWynia

JasonWynia

    Member

  • PipPip
  • 28 posts
  • Join Date: Nov 11 2003

Posted May 11 2005 - 12:13 AM

Yes I am using the zoom. Note that I'm not using the diagonal, but the width (which is constant when going from 4:3 to 16:9). The 55":33" image I'm getting right now at 100" is 64" diagonal, which is right inside the 62"-74" you're talking about. The goal is a screen at 78":43" 16:9 which is 89" diagonal (if my Pythagoras is right) or 15" beyond what the 4800 can do at 10'.

Now that I've taken a look at Projector Central's calculators, I've noticed their search tool that lets you search based on this criteria and I see that there are quite a few that *are* able to do to the 78" wide/89" diagonal at 10', which reinforces my plan to sell the 4800 and get a more suitable model.

The 4800/x1 is a great projector. It's just that I'm after a much bigger image than it can do in the room I have. According to the THX ratios/angles, I should actually be sitting about 3-4 feet closer to the current TV as well for a truly theatrical experience. That pretty much mirrors what I've been feeling since setting it up. While my current setup (and the x1/4800) would have provided a decidedly nice home theater, keeping my existing HDTV (which I'm happy with) and waiting to get a screen/projector that really does the immersive image size will give me the theater I'm really after.

Does anyone have any recommendations for a projector within that criteria?
J Wynia
(please call me J)

#6 of 7 Neil Joseph

Neil Joseph

    Advanced Member

  • PipPipPip
  • 8,338 posts
  • Join Date: Jan 16 1998

Posted May 11 2005 - 09:52 AM

Give us the exact dimensions from the back wall to where the screen will be hanging down. As long as this projector does not vent out of the rear, you can place on the back wall. You then have to subtract the physical length of the projector to get the distance from the projector's lens to the screen and then use this to calculate the throw size.
Click on above image to enter " T H E . H O L O D E C K "
---------------------------------------------------------
The Holodeck. My DIY Screen. DIY Subwoofer: The MaxCaliber
My humble collection of DVD's. HTF Beginner's Primer and FAQ

#7 of 7 JasonWynia

JasonWynia

    Member

  • PipPip
  • 28 posts
  • Join Date: Nov 11 2003

Posted May 11 2005 - 12:49 PM

That was how I got the 10'. The exact throw distance is 121" or 1" over 10'.

At this point, I'm pretty confident in the math that has me selling the 4800. That ship has pretty well sailed. Any solution that gets close is going to quickly dwarf (in terms of cash and effort) the price difference between what I'll get for it by selling and what a more appropriate projector will cost. I had already contemplated a variety of Rube Goldberg solutions including:

* Extending a hushbox into the garage, making the front plane of the projector even with the wall. (Turns out it would hit the car)
* Projecting upward onto a mirror and bounce to the screen, gaining about 18" or so. (Way too intrusive into the room and a lot of time, energy and money to get it working).

In short, there are quite a few projects I am willing to spend time coming up with a home brew solution, but I don't think modding the 4800 to get the bigger image is one of them.

So, I'm moving on to choosing a new projector. I'd like to figure out what is the *right* projector for my available throw.
J Wynia
(please call me J)




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users