[mbaxter]

I'm about to take the HTPC plunge but first I'd like to hear from those of you that have the Infocus X1. I have a 16:9 screen. When you hook the X1 up to a commerical DVD player, the best setup is to have both player and projector in 16:9 mode. The X1 crops to 800x450 and you get nice pixel-to-pixel mapping.


But when you pair the X1 up with an HTPC, there are several different ways that DVD's could be played such that they fit on my 16:9 screen. What do you guys recommend? The maximum resolution that the X1 can accept is 1024x768, though it can only display 800x600 pixels. Is it best to have the HTPC at 1024x768 when you play DVD's? Or should the PC native resolution be set to a widescreen ratio? With Powerstrip I suppose you could set the PC's native resolution to 800x450. Would that help or hurt PQ?


Basically just wondering what's the best way to run the X1 off an HTPC. All opinions/advice appreciated.


thanks in advance,

Mike

 

[mbaxter]

Anyone? Bueller?

 

[Eiffel]

Mike,


It is most likely best to send a signal that matches the native resolution and refresh rate of your projector. So that would be 800*[email protected]


This way, you'll let the computer do the scaling (in digital, thus with less 'errors'). If you want to adjust the picture (center it, zoom it, etc), doing it with your DVD software will give you the best results

 

[jvisaria]

I am using an X1 and HTPC.


difference was night and day for DVDs. My computer is very slow, and drops alot of frames so make sure you get a fast enough box.


If you have a DVD-ROM in your computer, try connecting it to the X1 just for kicks using the trial version of powerDVD or something. This will give you a little taste of what you can have with an HTPC....then imagine what you can do with serious tweaking.

 

[mbaxter]

Thanks for your responses guys.


Eiffel is there a disadvantage to using 75Hz input on the X1?


jvisaria - I have a spare P3-500MHz machine I was going to use. The videocard is an old Riva 128. Based on your own experience do you think that'll be enough?

 

[Eiffel]

mbaxter,


I suggest you try it, and decide what you like most (it might make the picture a little bit more jerky, as I believe this projector refreshes its display every 60th of a second)

 

[jvisaria]

Whether it will be enough or not i dont know.. i know it will be a ton better than what i am running ([email protected]).


From what I have learned reading the forums you will be able to get by with that... although others running ffdshow and all that other jazz seem to have much faster computers.. but just running powerDVD or something like that i dont think you will suffer from the same jumpy picture i am.


i am sure other users will be able to offer much more insight on this.

 

[mbaxter]

Eiffel - you're right it does make the image jerkier when you feed the projector 75Hz. 60Hz is smooth. This isn't something you notice except on scenes where the camera pans across a wide angle.


I'm still a bit unclear on something - for anamorphic DVD's, which of these scenarios is best:


1) Computer res at 800x600. Play DVD in anamporphic setting, where it's vertically stretched to 4:3 aspect ratio to fill the entire 800x600 area. X1 set to 16:9 so it squishes the anamorphic image down to fit my 16:9 screen.


2) Computer res at 1024x768. Play DVD in anamporphic setting, where it's vertically stretched to 4:3 aspect ratio to fill the entire 1024x768 area. X1 set to 16:9 so it squishes the anamorphic image down to fit my 16:9 screen.


3) Computer res at 800x450. Play DVD in widescreen setting, where it's in proportion and using the entire 800x450 area. This is assuming I can even get my HTPC to run an 800x450 desktop, and get the X1 to see it properly.

 

[Eiffel]

mbaxter,


for anamorphic DVDs, I would either use 800x600!60Hz (which I would set as my default, and only resolution), leave the PJ in 4:3 mode and adjust where the 16:9 picture displays in there using the DVD player settings, or use solution 3).


The idea is to not let you PJ do any of the scaling (from 1024x768 or 800x600 to 800*450), as the computer can do it much better, and once and for all (knowing that DVDs are originally 720x480)


Hope this helps

 

[mbaxter]

Yes that does help and makes sense. I just hate leaving my projector in 4:3 mode all the time, because I have a 16:9 screen. I should have bought a 16:9 projector, but the X1 was too good a deal at $1250 w/5 year warranty.


What I really need to do is figure out how to get an 800x450 desktop. I tried setting this as a custom resolution using powerstrip but the X1 couldn't sync to it (I got a vertically rolling image).

 

[KoolKiwi]

The reason why the X1 looks jerky at 75Hz, is that the colour wheel is frame rate locked from 48Hz to 62Hz (which is a great feature by the way). But if you feed it a signal above 62Hz then the frames are simply dropped, which is something you don't want to do with Video!


So best advice is to stick to 60Hz for NTSC, or 50Hz for PAL.


It's best to stick to the native 800x600 resolution with HTPC.


The advantage of HTPC is you have better control over colour rendition etc. using the video card overlay controls. Also, if watching Video source via a capture card, DScaler does a much better job of scaling IMHO, than the FL2200 chip (particularly with horizontal scrolling scenes and text).


Greg

 

[TomKal]

Hey KoolKiwi, looks like you just answered a question I had logged on to ask. I was unsure about the specs of the X1 colourwheel and what the best refresh rate for my HTPC would be.


From what you wrote, I'm now considering 48Hz since I am running something called ReClock which synchs audio and video source frame rate with your monitor/projector refresh rate to prevent frame loss and audio synch problems.

Since most movie material is ~24Hz, I was setting my refresh to 72Hz (3*24), but I supposed that might introduce frame dropping.


I thought I read somewhere though that the lower the refresh rate (and thus slower colourwheel) increases the liklihood of rainbows which I do ocassionally see in very high contrast pans.


I suppose my best bet is just to experiment with different setting?

 

[KoolKiwi]

Hi Tom,


Yes, your best bet is to experiment.


A multiple of the source frame rate is best to get the smoothest pans etc. (I run my CRT at 72Hz for NTSC DVD source).


However, it is true that by lowering the refresh rate to 48Hz you are increasing rainbow likelyhood, but of course this is subjective, so you need personal experimentation!


I found out this spec of the X1 from Bob Williams (from InFocus), so it is a reliable source. This was when I originally wanted to run at 75Hz to try and get an effective 3x colour wheel speed for PAL 50Hz source via HTPC.


nb: You can actually hear the wheel change speeds (when you go between 50Hz and 60Hz for example).


Greg

 

[mbaxter]

Quote:

Originally posted by KoolKiwi So best advice is to stick to 60Hz for NTSC, or 50Hz for PAL. It's best to stick to the native 800x600 resolution with HTPC.

But I have a 16:9 screen, so the only way I can get pixel-to-pixel mapping from the HTPC to the X1 is by running the desktop at 800x450.


Anybody know how to do this?