Color jetBook Color under the microscope

[andyh2000]

Since some people wonder how the jetBook Color renders coloured text at a lower apparent resolution than black text I thought I'd stick it under the microscope again to demonstrate. This is a small PDF just consisting of four lower case 'a' characters in black, red, green and blue. The black one uses all the sub-pixels available (1200x1600 of them at approx 206dpi) to render a nice smooth letter form. The coloured ones basically blot out the unwanted colour sub-pixels giving a checkered and slightly jagged effect, although it doesn't look anywhere near as bad on screen as it does in the magnified photos. I got bored before doing the green pictures...

Incidentally I used a trial version of Autopano Pro to stitch together the high magnification pictures out of smaller sections - I think I'll be buying it as it makes the job really easy.









Andrew

[ProDigit]

I suppose the text appearing within the pixels is from your (russian) software?

[andyh2000]

Originally Posted by ProDigit

I suppose the text appearing within the pixels is from your (russian) software?

It's the watermark from Autopano Pro. I don't think it's Russian though - I think somehow some of the letters are overlapping so it looks weird.

Andrew

[wallcraft]

Before seeing this, I had completely the wrong idea about how it works. As you say, the black really is 206 dpi, since all the pixels (RGBW) are black! Obvious when you see it magnified.

It is also now clear why the colors are so washed out, pure red (say) is one part red and 3 parts black.

[andyh2000]

Originally Posted by wallcraft

Before seeing this, I had completely the wrong idea about how it works. As you say, the black really is 206 dpi, since all the pixels (RGBW) are black! Obvious when you see it magnified.

It is also now clear why the colors are so washed out, pure red (say) is one part red and 3 parts black.

For some reason pure green uses the green and clear pixels whereas pure red and blue are one pixel of the colour and up to three pixels of black - I assume light red would have the R and W pixels white and the G and B pixels black. Lots of fun to be had - I haven't had much time since getting the jetBook Color but I'll try and add a few more investigations as time permits.

Another interesting thing to notice is that even the coloured letters aren't actually too blocky in outline - they still use the 1200x1600 sub-pixels and aren't made out of solid 2x2 square "Lego bricks".

Andrew

[ProDigit]

For colors I'd expect to have one color, one white, and the other 2 black...
I guess it depends on the gradient of color.
If you have FF,00,00 maybe it shows more black pixels, while FF,80,80 might show less black.

It would be nice to go into MS paint (the one provided by your Windows) and manually select a color (double click the color, and change the color value from 0 to 255); and paint some small squares and do some testing like that.
I have a microscope which I'm planning on using, unfortunately it does not have a USB connection for image transfers to pc's.

[Dulin's Books]

i wonder if a pentile arrangement of the filter would be better than the grid the are using?

[mod186k1]

The real "problem" (as if it is a problem) is the contrast. Looking at this photo:


Triton Filter seems a little more darker than non-pearl b/w eink. But it seems to me better then Sipix® screen.

Can someone do a comparative photo?

[DaleDe]

Thanks Andrew. This illustrates the effect nicely. In particular the first image can be clicked twice to make it large enough to actually see the difference in smoothness of the various characters in my browser. What size font is it? You have to wonder if a little more clear pixels on in red and blue might brighten the colors a bit but perhaps what they have done is the best. If the font is larger I would expect the color to be more apparent.

Dale

[andyh2000]

Originally Posted by DaleDe

Thanks Andrew. This illustrates the effect nicely. In particular the first image can be clicked twice to make it large enough to actually see the difference in smoothness of the various characters in my browser. What size font is it? You have to wonder if a little more clear pixels on in red and blue might brighten the colors a bit but perhaps what they have done is the best. If the font is larger I would expect the color to be more apparent.

Dale

It was 14pt Times New Roman bold "printed" to an A4 PDF which is then displayed fullscreen on the jetBook Color.

Here are some more. A 28pt red 'a' (I'll try light red later):





and a black-grey-white scale (clearly in full 1200x1600 resolution as well). Greyscale comics looks great on this device. The cyan stuff is again the watermark of the Autopano Pro software - I must get myself a license as it's great for stitching stuff together automatically.



Andrew

[ProDigit]

You can clearly see the 8 'a's in the small view of the gray scale picture, while in enlarged view the last a is barely visible!

[andyh2000]

Just for comparison here are the equivalents on an iPad 1. I know which I prefer reading off (as long as the ambient lighting is good).







And what do you know, pure red on an iPad is a mixture of red and black.

Andrew

[ProDigit]

yeah, but pure red on an ipad is LIGHT SOURCE red, not filtered red.
Filtered red always looks much darker than light coming from a light source.

[andyh2000]

Originally Posted by ProDigit

yeah, but pure red on an ipad is LIGHT SOURCE red, not filtered red.
Filtered red always looks much darker than light coming from a light source.

Only if the brightness of the ambient light after reflection and filtering is less than the LCD brightness. Which it usually is of course, and that's one of my problems with the iPad. I can't turn the brightness down far enough to match the ambient lighting conditions.

Andrew

[ProDigit]

...which is one of the reasons why people are complaining about reading from a pc.
On one of the first netbooks, you could hack the firmware to set the screen so dark, that it'd be hardly viewable even in a pitch black environment!

Having the possibility to reduce screen brightness to 10 nits or lower, can allow you to set perfect lighting conditions to read on an LCD (not to mention save plenty of battery in the process too).