Trouble displaying on dual 1024x768 projectors

Hi Chief-Beamer,

I’m using two (rather old - 15 years - InFocus X3) 1024x768 projectors and I’m getting unexpected results when trying to display a single 2048 by 768 image. I’m using the dual-display option [ 1 ][ 2 ] and I’m getting something like half of the left side of the image on one screen, and half of the right side on the other.

I’ve tested my setup on 2 (much newer) 1920x1080 regular screen displays with a 3840x1080 image and it works as expected.

Since the projectors are old and don’t support 1080p (only max.1080i) I’m wondering if I can override the dual-display resolution options with other video modes that might work better with my ancient projectors.

Thanks much,

Chris in Montreal

Hm. You’re right. It seems like all the dual display configuration options on the web dashboard currently expect FullHD resolution. Will be fixed soonish.

If you want to manually fix this temporarily, you can edit the /config/dual-layout.json and replace 1920/1080 with 1024/768.

Great news. Thanks.

Should I be concerned about hdmi_modes?

I’ve tested hdmi_mode’s 16 to 19 (hdmi_group=2) and they all work in single display setup.

Chris in Montreal

They will all use in dual display mode as well as long as the dual-layout.json file exists as contains the correct values. Example:

   "dual_offset_x": 1024,
   "dual_offset_y": 0

activates a second display and places the top left corner of that display 1024 pixel right of the top left corner of the first display. The UI configuration on the website generates those files as well, but does it wrong for anything outside of FullHD.

Thanks again. I have another pair of old projectors that do 1280x800 natively. If you could include that resolution in the coming update, that would be nice.

Much appreciated.

Chris in Montreal

You made my Day/Month/Year!

Thanks for updating the edit-configuration options so quickly - works great with my (ancient) projectors now!


Happy to hear. Thanks for confirming.

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