Registered: Feb 2001
Location:
Posts: 2

I read a review of Visor on PDABuzz.com:

http://www2.pdabuzz.com/Reviews/Det...isor_Prism.html

that claimed Visor cannot display true 16bit color. Specifically, that the color range available at each pixel can *not* be one out of 65000.

Can someone please confirm/deny this?

Thanks,
Douglass Turner
email: [email protected]

Registered: Oct 1999
Location: Baltimore MD, USA
Posts: 717

I might be misreading the article, but what they seem to be saying is that the Prism cannot display 65,535 different colors simultaneously, due to the simple fact that the screen doesn't have that many pixels.

So what? Who would want to do such a thing anyway?
Otherwise the Visor does display true 16 bit color, with a resolution of 160x160 pixels.

Registered: Nov 1999
Location: Ann Arbor, Michigan USA
Posts: 790

From the article:

quote:

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... the unit itself does not have the ability to take full advantage of all the colors it can display. This is due to simple mathematics. Unless I'm wrong, a pixel can only display one color at a time, and once you realize that the Prism's 160x160 display only has 25,600 pixels total, you'll see that at any given time, the Prism is only capable of using around 40% of the 65,535 colors advertised. Now don't get me wrong, this is not immediately a problem since many color apps only support 8-bit color in the first place, but if you're planning on getting a Prism to take full advantage of its 16-bit color, you may want to consider the fact that the numbers are not in your favor.

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Jeff

Registered: Jan 2001
Location: USA
Posts: 54

just when you think you've seen it all....
This must be about the most stupid review I have seen! Who cares if you don't have enough pixels to display 65000 colors at the same time - just look at Mindspring's example photos and what they look like if displayed in 8 bit (yuck) or 16 bit color (yummy)! If you want color at all (surely debatable), get 16 bit or forget about it. And no, I did not count how many different colors the example photos have... I leave that up to the next reviewer who can spend a few weeks doing that. I just look at the photos and see the vast difference.

Registered: Aug 2000
Location: Alive and well on VisorCentral.com
Posts: 861

A picture is worth a thousand words.

Registered: Jan 2001
Location: Austin, TX
Posts: 49

quote:

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Originally posted by nightingales
just when you think you've seen it all....
This must be about the most stupid review I have seen! Who cares if you don't have enough pixels to display 65000 colors at the same time

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Registered: Oct 2000
Location: Phoenix, Arizona
Posts: 80

quote:

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Originally posted by EricG
A picture is worth a thousand words.

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A 16-bit COLOR picture that is!

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I do NOT look wierd! I just look ... "different".

Registered: Feb 2001
Location:
Posts: 2

All,

Thanks for clearing up the simultaneous color issue.

Note, the higher the bit depth at each pixel the less contouring or banding you will see in images with ever so subtle luminence variations. This artifact is a result of color values being quantized into too few "buckets".

24-bit is probably silly for a PDA but I think 16-bit is as low as you want to go. If there was a way to display 16-bit *greyscale* images on Prism *that* would look delish.

Registered: Jan 2001
Location: USA
Posts: 54

quote:

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Originally posted by dugla
All,

... If there was a way to display 16-bit *greyscale* images on Prism *that* would look delish.

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Registered: Jan 2000
Location: Twin Cities, MN
Posts: 1683

nightingales:

You are correct, there are only 256 shades of grey available on a computer monitor, therefore, there really isn't such thing as 24-bit greyscale.

Also note that most humans can't tell the difference between 24 bit color and 32 bit color on a monitor, and, technically, a monitor can not render 32 bit color anyways.

Each color channel contains 8-bits of information (256 shades). You have 3 channels: R, G, and B, which leaves you with an extra 8 bits if you are in 32 bit mode. In some software applications, you can save a file in 32-bit mode. The extra 8 bits are typically left for use as a masking layer (alpha channel).

On a computer, 32-bit graphics tend to be faster than 24-bit (due to how the computer processes data...I can't exactly explain this part) but there really isn't a visual advantage from the color standpoint.

Now, hopefully, sometime in the future, we WILL have monitors that can display a wider range of color. To do this, they need to increase that available number of shades in each color channel and/or add more color channels and/or start playing with some other technologies (ie, 'paper' monitors that use reflective light rather than projected light).

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Registered: Aug 2000
Location: Alive and well on VisorCentral.com
Posts: 861

I agree with only being able to see 256 shades of grey, but then again the human race has done just about everything else for even less viable reasons, put cheese in side of pizza crust, shamrock shakes, etc.., so why not 32-bit grey scale.

Registered: Oct 2000
Location: Aberdeen, SD
Posts: 2531

quote:

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Originally posted by EricG
...put cheese in side of pizza crust...

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-Joshua
Abortion: Darwinism at its finest.

Registered: Jan 2000
Location: Twin Cities, MN
Posts: 1683

Eric:

Oh...I totally agree with you. It's just that we've kinda standardized on this whole 3-channel, 256 shade system.

I'm sure things will change over the next decade or two. The advent of digital ink is a really interesting development. Think of you monitor as being as high-resolution as a piece of paper and as small as one too. Granted...that is a LONG ways away, but maybe in 10/20 years we'll have that.

We're already beginning to push beyond the defacto CMYK print standard. You can even get home-use ink jet printers that print with 6 colors rather than 4...which allows for a MUCH broader color space than traditional printing can offer.

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We're all naked if you turn us inside out.
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Registered: Aug 2000
Location: Alive and well on VisorCentral.com
Posts: 861

Actually there is such a thing as 32-bit grey scale. Just in medical imaging devices and such.