Can't Airplay my MacBook in 16:10 full screen with Apple TV - why not???

usagora

macrumors regular
Original poster
Nov 17, 2017
205
121
I'm trying to Airplay my 13" MacBook Air (16:10 aspect ratio) using my Apple TV HD (can be set to 16:10) connected to an Epson Projector (16:10). But no matter what combination of settings I try, the darn image won't fill the entire 16:10 projected/lit screen. My projector's native resolution is 1280x800.

(1) If the Apple TV is set to 1080p resolution and the MacBook scaled to 1280x800, the projected image is 16:10 but letterboxed all around.

(2) If the Apple TV is set to 1280x800 resolution and the MacBook scaled to 1280x800, the projected image is some odd aspect ratio, letterboxed slightly on the sides and cut off at the top and bottom.

(3) If the Apple TV is set to 1280x800 resolution and the MacBook is set to "Optimize for Apple TV", the projected image is 16:10 but cut off all around. I tried turning the "Underscan" setting on the Apple TV to "on" but it makes no difference.

(4) If I connect the MacBook directly to the projector using an HDMI cable and HDMI to Thunderbolt adapter and scale the MacBook to 1280x800, the projected image is PERFECT (16:10 full screen). So why the heck can't I get that same image with AirPlay???


(1) Apple TV 1080p / MacBook 1280x800 = 16:10 letterboxed all around
01 ATV1080 MBA-BI1D280.JPG


(2) Apple TV 1280x800 / MacBook 1280x800 = odd aspect ratio letterboxed on sides and cut off at top and bottom
02 ATV1280 MBA-BID1280.JPG


(3) Apple TV 1280x800 / MacBook "optimized for Apple TV" = 16:10 cut off all around
03 ATV1280 MBA-ATV.JPG


(4) Direct MacBook to Projector connection via HDMI = 16:10 full screen (this is what I want!)

04 HDMI MBA-BID1280.JPG
 

usagora

macrumors regular
Original poster
Nov 17, 2017
205
121
Any help here, folks? I also posted on Apple discussion forums, and all I've gotten so far is a reply from someone who didn't read beyond the thread title (told me that Apple TV can't send a 16:10 signal when it clearly can as described/shown in my actual post - it's just either zoomed too far out or in).
 
Last edited:

waw74

macrumors 68040
May 27, 2008
3,446
315
on the aTV, In the settings app, Airplay section
try playing with "airplay display underscan"

that might help, but not 100% sure.
 

usagora

macrumors regular
Original poster
Nov 17, 2017
205
121
on the aTV, In the settings app, Airplay section
try playing with "airplay display underscan"

that might help, but not 100% sure.
Unfortunately, as mentioned in the post, that did not make any difference.
 

StandingGoose

macrumors member
Mar 24, 2017
42
36
Which Epson projector model? You should poke around in the manual and/or onscreen menus to see if anything applicable appears.

I vaguely recall wrestling with an Hitachi projector that, for reasons I could not fathom, had the option of overscan when connected via HDMI.
 

usagora

macrumors regular
Original poster
Nov 17, 2017
205
121
Which Epson projector model? You should poke around in the manual and/or onscreen menus to see if anything applicable appears.

I vaguely recall wrestling with an Hitachi projector that, for reasons I could not fathom, had the option of overscan when connected via HDMI.
Been there; done that. The projector (I use both a PowerLite 485W and EX7210, both of which have the same resolution and settings) has various aspect ratio settings, but none of them corrects the image. There is an overscan setting, but none of the levels of overscan fix it either. If I recall correctly, they actually zoomed into the image itself, rather than make the image larger.
 

StandingGoose

macrumors member
Mar 24, 2017
42
36
Does the Epson "Projector Information Display" show any difference between the direct connection to the iPad and when connected via Airplay?
 

usagora

macrumors regular
Original poster
Nov 17, 2017
205
121
Does the Epson "Projector Information Display" show any difference between the direct connection to the iPad and when connected via Airplay?
To clarify, I'm connecting my MacBook Air, not an iPad. I'm not sure if I've ever looked at a "Projector Information Display" or what that exactly is (assuming it's some sort of overlay showing the connection status?), but I'll see if I can find out tonight. Thanks.
 

usagora

macrumors regular
Original poster
Nov 17, 2017
205
121
Does the Epson "Projector Information Display" show any difference between the direct connection to the iPad and when connected via Airplay?
So based on the info shown from the projector (see images below), the Apple TV is apparently still feeding it a 1080p signal, even though the Apple TV's resolution setting has been changed to 1280x800. So I've concluded that the Apple TV is merely downscaling and "squishing" a 16:9 1080p image to make it only appear to be 16:10 1280x800 image, which would explain why no setting I change on the projector or MacBook can make it look right, because it's being fed through a distortion filter (Apple TV), as it were. Disappointing, but at least I have an AirPlay option in the room now, which makes it a more flexible setup, even though it can't take advantage of the entire screen :confused: I already knew it wouldn't for iPhone/iPad due to those devices having different aspect ratios than the projector, but I figured the MacBook wouldn't be an issue since it has the same aspect ratio as the projector. Guess I was wrong.

Thanks, StandingGoose, for your help.

INFO WHEN CONNECTED VIA HDMI
IMG_0276.JPG


INFO WHEN CONNECTED VIA AIRPLAY (APPLE TV SET TO 1280x800)
IMG_0279.JPG
 

StandingGoose

macrumors member
Mar 24, 2017
42
36
The 1080p may be a symptom: When in "Component" mode the projector (I'm looking at the EX7210 manual) can't do 1280x800. It looks like there's an "Input Signal" setting where you might be able to force it to RGB instead.
 

usagora

macrumors regular
Original poster
Nov 17, 2017
205
121
The 1080p may be a symptom: When in "Component" mode the projector (I'm looking at the EX7210 manual) can't do 1280x800. It looks like there's an "Input Signal" setting where you might be able to force it to RGB instead.
I will check it out!
 
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