Rotating screens 90 deg alters perceived picture quality

[JohnnyBoy]

I've currently got my Mini linked to two 20" displays in 'landscape' orientation. This gives a total desktop resolution of 3200 x 1200 pixels, which is very wide picture shape, 8:3.

But these screens can pivot thru 90 degrees into 'portrait' orientation. When I realised that I could get a resolution of 2400 x 1600 pixels by doing this (which isn't far from the 30 inch ACD's resolution of 2560 x 1600) I had to give it a go.

But when I did, I found that the picture quality was... different. When looking at text, the contrast between the black of a character and it's light background wasn't so stark and the edges of the character became fuzzier and indistinct.

So my question is: Does anyone else see this effect when they look at their display after tilting it (or their head) thru 90 degrees?
(I've got a feeling that it's something to do with the nature of our stereoscopic vision...)
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Intel Mini 2.0GHz C2D (4GB/120GB/SuperDrive/10.5.8 ), 120GB WD Passport, Logitech ergo k/b
iPod Touch (32GB, 3rd gen), iPod Shuffle (512MB, 1st gen)

[philiparcario]

my 24 inch screen. has a rotating pivot so I can have it as a narrow tall screen. good for viewing long email lists. I hate it the print seems wrong I don't know if it is the screen or my eyes.
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2010 Mm 2.4 C2D oem 320gb hdd 8gb ram
2012Mm base 2.5 with 16gb ram diy fusion drive
2012Mm quad with 8gb ram oem 1tb hdd

promise pegasus r6 3x 3tb + 3x 4tb =21tb hdds
lacie little big disk 2x 512gb ssds
synology 2tb disk station

[JohnnyBoy]

[philiparcario]

maybe the pixels are not square?
_________________
2010 Mm 2.4 C2D oem 320gb hdd 8gb ram
2012Mm base 2.5 with 16gb ram diy fusion drive
2012Mm quad with 8gb ram oem 1tb hdd

promise pegasus r6 3x 3tb + 3x 4tb =21tb hdds
lacie little big disk 2x 512gb ssds
synology 2tb disk station

[JohnnyBoy]

Yes, that could be it. Perhaps that would mean that the gap between the left/right sides of the pixels is a different size to the gap between the top/bottom sides of the pixels.

Anyway, whatever the reason... I now know that it's not my eyes that are going screwy!
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Intel Mini 2.0GHz C2D (4GB/120GB/SuperDrive/10.5.8 ), 120GB WD Passport, Logitech ergo k/b
iPod Touch (32GB, 3rd gen), iPod Shuffle (512MB, 1st gen)

[MacDSmith2]

It would surprise me if the pixels were square and not rectangle. NTSC Digital Video is rectangular pixels, 720 by 480.

"For example, LCDs typically divide each pixel horizontally into three subpixels. (When the square pixel is divided into three subpixels, each subpixel is necessarily rectangular. To make them less oblong, two subpixels per color are used, see pixels on an LCD TV.)"

http://en.wikipedia.org/wiki/Pixel

Added: "However, some imaging systems, especially those which must maintain compatibility with Standard-definition television motion pictures, define an image as a grid of rectangular pixels in which the width of the pixel is slightly different from that of its height." - same reference
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Retired: Altair 8800, PET, TI 99/4A, Apple II
Mac Plus, Mac II, Mac SE/30, Quadra,
20th Anniversary Mac, iMac Purple, G4 Blue & White, iBook Clamshell
Active: Mac Mini (OCT 09) 4 GB RAM, 2.66 GHz, 500 GB HDD

[Smithcraft]

Perhaps since the refresh, if flat panels refresh like CRTs did, is going from side to side instead of top down, that might be causing a problem.

However, I suspect that in the engineering of the panel, it was decided that it should be designed to look best in one particular orientation. Because of this, other orientations might not have a good appearance.

Can you rotate it around so that it's upside down and try that?

SC
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Grumpy old man of computing.

[Desktop] G4 mini - 1.5Ghz 1GB 80GB HDD - Newer miniStack v2 500GB - 10.5.8

[Media System] Intel i5 mini - 2.33Ghz 8GB 500GB HDD - 4 x Hitachi 2TB HDD in a qBOX-SF - 10.7.5 (Thanks Phil!)

Make sure it has pins!

[JohnnyBoy]

[twitch]

Do these displays happen to be TN displays? My low cost TN display would look awful rotated into portrait mode. The more expensive IPS looks great portrait or landscape because it appears to have better viewing angle regardless of portrait/landscape
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Mac Mini (mid '09) 2 ghz, 4gb ddr3, intel SSD 80gb g2, bose qc2 headphones, 24" Dell LCD 3008wfp + 2408wfp, apple wireless keybd, logitech g7 mouse, hp 2600n color laser printer; lenovo x61 tablet; Blu-ray HTPC/gaming rig win 7

[JohnnyBoy]

[twitch]

*font smoothing on snow leopard for non-apple displays:
opening Terminal and entering defaults -currentHost write -globalDomain AppleFontSmoothing -int 2
LINK: http://blog.jjgod.org/2009/08/18/snow-leopard-vs-dell-lcd-displays/
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Mac Mini (mid '09) 2 ghz, 4gb ddr3, intel SSD 80gb g2, bose qc2 headphones, 24" Dell LCD 3008wfp + 2408wfp, apple wireless keybd, logitech g7 mouse, hp 2600n color laser printer; lenovo x61 tablet; Blu-ray HTPC/gaming rig win 7

[Smithcraft]

[JohnnyBoy]

Well, whatever the cause of the lousy picture, I'm not going to try to run these screens in portrait mode; I'm gonna achieve a 1600 pixel desktop height by buying a 30 inch screen.
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Intel Mini 2.0GHz C2D (4GB/120GB/SuperDrive/10.5.8 ), 120GB WD Passport, Logitech ergo k/b
iPod Touch (32GB, 3rd gen), iPod Shuffle (512MB, 1st gen)