I’m happy to post my experience of using the HC4000 in a CIH setup. I learned a lot from these forums and this is my way of contributing back to the forum.
My projector is mounted exactly 13’-6” from the screen and is ceiling mounted, with the bottom of the projector at 95” from the floor. My screen is a 47” x 110.5” custom made 1.2 gain fixed frame screen with an aspect ratio of 2.35:1. The bottom of the screen (excluding 3” frame) is exactly 30” from the floor.
I first floor mounted the projector at 13’-6” to test the image size and configured the projector for the default 16:9 aspect ratio (under Menu -> Image -> Advanced Menu -> Screen Size -> 16:9). Then I used the zoom lens to arrive at the equivalent 16:9 “frame” for a 2.35 image. The way the Mitsubishi does CIH is different from other CIH-capable projectors like JVC or Panasonic AE40000. The Mitsubishi uses the “shrink method” to do a Constant Image Height.
First, I decided on the size of the 2.35 image I wanted. My HT room is 19’ x 14’ with my seating at 13’-6”. I simply placed the projector on the floor at this distance, connected my WDTV to it and started projecting a 2.35 movie on to a blank wall to decide the image size I wanted. For my room size, I felt that 47” x 110.5” (120” diagonal) would be a comfortable image size for a 2.35 aspect ratio movie. I could have gone with the larger and more standard 115” x 49” size, but this would mean that the width of the image would leave too little space for the front speakers to fit in at the sides (see my photos below – I don’t have an AT screen) and I couldn’t “take in” the entire image of that size at one glance.
All these calculations were performed while the projector was running in the standard 16:9 mode. Which means that the image being projected was actually 110.5” x 62” (127” diagonal) with black bars on top and bottom. So while calculating throw distance, mounting height and screen size by using either the projector central calculator or Mitsubishi HC4000 website calculator, I had to input the 16:9 size. To achieve a CIH image where the height of the image is restricted to 47” whatever be the aspect ratio, I had to go to Menu -> Image -> Advanced Menu -> Screen Size -> 2.35 (CinemaScope). Immediately, the projector cuts off the black bars on top and bottom and only the image of 110.5” x 47” is projected. The cool thing here is that we can digitally “shift” the 2.35 image within the larger 16:9 frame so that the extra 15” (i.e. 62" - 47") can be at the bottom or top of the screen. So, while the bottom of my original 16:9 image was just 15” from the floor , the 2.35 image was a comfortable 30” from the floor. This digital shift can be saved in one of three programmable memory slots (on the remote cum projector), along with other settings like screen size (2.35:1 or 16:9), gamma etc. Everytime the projector is switched on, it defaults to the last used memory setting. So if you last used a memory setting of 2.35 screen with a digitally shifted image, this is what will be the default everytime the projector switches on.
In order to view 16:9 content, all I had to do was press the Aspect button on the remote. When selecting 16:9 as the aspect ratio, the HC4000 resizes the image to fit the CIH height of 47”, make the width 83.6” (and therefore 96” diagonal). I can assure those who are contemplating a CIH setup that this scaling algorithm is superb and one can hardly detect that the image is being rescaled. All I need to do to move from one aspect ratio to another is hit the Aspect button. There is no need to change the zoom settings of the projector or shift its location etc. This is a simple and brilliant way of doing CIH.
I did notice a slight drop in brightness under this CIH setup, primarily on account of the huge size of the image (remember that the projector is actually projecting a 127” 16:9 image but with the top and bottom 7.5” cut off digitally). But another forum member told be to turn on Brilliant Color which gave me the sufficient brightness while still running on Low lamp mode and while keeping Gamma at Cinema mode. I know that ultimately I have to switch to “Standard” (i.e. high) lamp mode to boost the lumens as the lamp life ages but its about how much I can postpone it. I usually average about 700 hours a year, so even fully under standard lamp, it should last about 3.5-4 years.
I used the AVS709 calibration series to basically set the brightness and contrast. As reported by others on this forum, the Mits is superbly calibrated out of the box and nothing needs to be touched except the brightness and contrast. My primary video component was my HTPC running a ATI HD5850 under Windows 7 SP1 with XBMC. I had connected this to my Onkyo TX-SR605 receiver through HDMI and the AVR is connected to my projector using a Sabrent CAT5-HDMI balun which I bought from Amazon. This is because my house is prewired using 2” PVC conduits which are too small for the HDMI headers to fit into, much less turn at the bends in the wall and ceiling. So I had no choice but to run 30' of CAT5 wiring between the AVR and projector and used the balun to do the conversion to HDMI. It worked pretty well and I was able to push a 1080p@60Hz signal with no problem. The only glitch is that in Windows, under the ATI catalyst menu, I could only select the Ycbcr 4:2:2 color space under the Pixel Format category. Any other selection was not accepted by the Mits and resulted in severe noise or grains. I attribute this more to the limits of the HDMI extender rather than the projector or HTPC because when I tried connecting it earlier with a direct HDMI cable it worked perfectly. Also, when using the Black Clipping test of the AVS709, I realized that I was able to see all the bars on the test, which meant that I wasn’t seeing any “true black” but only shades of grey. See this post
for more info on how I solved it.
In the end, I’m pretty happy with the way my projector and screen have turned out. The CIH setup is superb and its is the way movies have to be watched. The real beauty of CIH is that it “expands” when watching a 2.35 movie and “shrinks” back when watching 16:9 content, which is how movies are supposed to be. My earlier setup consisted of an Infocus IN72 480p projector with a 110” 16:9 manual pulldown screen. There is a HUGE difference after the upgrade on multiple counts – increase in resolution to 1080p, the amazing sharpness of the Mitsubishi HC4000, the 2.35 fixed frame screen and the colors and “pop” of the new image. I used to watch 110” TV shows and much smaller 2.35 movies. Now it’s the exact opposite, and I don’t consider the reduction in size in 16:9 content from 110” to 96” as very significant because of the overall setup and quality. Also considering that most of my 16:9 content is TV shows which aren’t that great in quality to begin with, a smaller image only improves the visual quality. Also, the latest version of XBMC which is about to release ("version "Eden") is supposed to be CIH friendly, meaning that it can automatically position subtitles with reference to the image bottom irrespective of aspect ratio, so I don't have to suffer not having subs when watching 2.35 content.
The images below show my HT and XBMC setup and a 16:9 scene from Sex And The City and another 2.35 scene from Clash Of The Titans. I had a lot of difficulty in taking the photos despite having a DSLR due to my limited photography knowledge and because the room is pitch black when lights are turned off (I cannot see my hand in front of me). Either the photos were under or over exposed and I did not have enough time to learn the correct settings as I wanted to get this post out. So attribute any shortcomings in the quality of pictures to the photographer rather than the projector or htpc. Any suggestions on taking photos are welcome!
I also want to thank all those who have helped me with the CIH concepts and Mitsubishi reviews and helped me make this setup possible. Specifically I want to thank coderguy, bishopt, cuttard, fleaman, cavx, joesyah, steven56, coolrda for their valuable inputs! I am also posting references to this in the CIH section so that it will help other potential CIH wannabes!