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borat
25th August 2004, 04:36
can Modern LCD's actually fully produce anything above 16bit colour depth? i seem to remember reading ages ago they could not but wondered if things had changed at all
cheers
will

JTD
25th August 2004, 05:31
Originally posted by borat
can Modern LCD's actually fully produce anything above 16bit colour depth? i seem to remember reading ages ago they could not but wondered if things had changed at all
cheers
will

At least some can:

http://www.viewsoniceurope.com/dk/Products/LCDGraphics/VG700b.htm

Look under the specifications (a bit down on the page): TFT active matrix SXGA LCD (16.7 mio colours).

Greebe
25th August 2004, 05:40
only the higher end models can, most a far less and even then are interpolated (correct term?... tired) from a much lower color depth, typically 6-8 bit if memory serves me correct

Fluff
25th August 2004, 05:48
On another note... With DVI, what is the maximum number of colours that can be sent? 16.7million?

Greebe
25th August 2004, 06:02
Would you like the DVI 1.0 spec pdf... will up it to my ftp

or you can grab it yourself from www.ddwg.org after registering :)

Jammrock
25th August 2004, 06:05
The main reason why manufactures go with 6-/8-bit is because it's cheaper and they get better response rates. All the sub-20 ms refresh LCDs are 6-bit color depth. So if you're looking for a dual gaming/graphics/CAD style LCD, you're screwed.

The recommendation is to get the LCD that fits the bill best, i.e. whether graphics and color are more important than refresh rate for gaming and video.

Jammrock

rylan
25th August 2004, 07:06
Yeah a lot of the 15" and some 17" LCDs use an interface from their A/D electronic board to the panel called '6bit +2FRS', or actually use native 6 bit glass. With 6bit you get 262K colors. The "FRS" method is basically an interpolation done on the scalar chip so they can use a cheaper dvi receiver and cheaper scalar. You won't get 16.7mil colors with that obviously, but its better than the 262K.

Now, even though the better LCDs (from 19" up) claim 16.7million colors due to 8bit/color, you're not realistically going to get that because of technological limitations of the actual LCD crystals and structure of the panel. Instead of 24 bits, its closer to 21 bits of actual visible color data if measured. Thats where CRTs are still superior to LCDs... accurate color reproduction.

borat
25th August 2004, 07:55
well i just had the weirdest thing happen, i currently have a dell 20" LCD connected via DVI to a radeon 7000 PCI, i had the colour depth set to 32 bit. When i tried to scroll in any application it cursor would low down to a crawl and it would scroll pitifully slowly when veiwing things like these forums, now i have the colour depth set to 16 bit and everything is fine. Found it quite bizarre as it never happens when the screen is hooked onto my parhelia.

UtwigMU
25th August 2004, 08:19
borat, I think Radeon7000 might run in memory limitations at 16x12@32-bit.

borat
25th August 2004, 09:04
not really up to speed with memory limitations and Resolutions, what do you mean by this?

Greebe
25th August 2004, 09:14
Originally posted by UtwigMU
borat, I think Radeon7000 might run in memory limitations at 16x12@32-bit.

I don't.

The PIT
25th August 2004, 09:32
This is why I'm thinking off buying another CRT for my Photos. The differance between the print outs and whats is displayed is quite marked with my Dell.

Didn't have that problem with the CRT.

Yes I'm am using the correct icc for both devices.

I then think about ATI's drivers getting mixed up over which driver too use when you have two very different monitors.

rylan
25th August 2004, 09:45
Borat, you're pushing too much data over the PCI bus and saturating the available bandwidth at that resolution and color depth... hence the apparent slowdown.

Fluff
25th August 2004, 10:09
http://www.candescent.com/showcase.htm#Product%20Display

Problem solved.... Well not quite yet..

Wombat
25th August 2004, 13:16
Originally posted by rylan
Borat, you're pushing too much data over the PCI bus and saturating the available bandwidth at that resolution and color depth... hence the apparent slowdown. I doubt that's what is happening. Maybe a bus-mastering issue, or badly installed drivers, or something.

rylan
25th August 2004, 16:15
Hmmm at 1600x1200@60Hz thats 115Mpixels/sec. With each pixel being 32 bits, thats 115*4bytes/pixel = 460MB/sec for minimum internal card memory bandwidth, plus whatever is needed for the rendering engine to actually process the data.

According to the ATI spec, the pixel fillrate of the Radeon 7000 PCI card is 332Mpixel/sec (unfortunately they don't give raw bandwidth), so you'd think its enough with a 115Mpixel/sec requirement.

I think if it wasn't using busmastering it would be slow at 16bit also, especially during HD access.

VJ
26th August 2004, 00:31
Any idea what is meant with this:
http://www.eizo.com/products/lcd/l568/spec.asp
Display Colors: 16.77 million from a palette of 1.06 billion

The Pit:
I recently purchased this Eizo monitor, and it does seem to give superb quality for photoediting. It is currently configured to switch to sRGB (there is an appropriate icc profile) when any of my photo-editing softwares are launched. I haven't been able to verify how good colours match, though...


Jörg

borat
26th August 2004, 03:46
well, putting things down to 16 bit has definately solved the problem, wish i had gone for an old matrox PCI card now, was looking to save a few pennies at the time and was convinced that a radeon 7000 would be as fast as an older matrox card at 2d rendering, live and learn i suppose!
thanks for input

rylan
26th August 2004, 05:53
The thing Eizo talks about is using a 10bit internal lookup table on the scalar board in the panel to generate the 8bit color data, so that when you perform gamma correction you don't lose any colors. Of course this assumes the gamma color curve correction is being done in the panel and NOT on your commercial graphics board through windows, otherwise you don't get the benefit (which is pretty dubious because for normal desktop use and even design nobody is going to notice when working with a color display).

Even so you still don't get true 8bit/pixel color depth because of the reasons I mentioned earlier about lcd limitations.

spadnos
26th August 2004, 08:42
@rylan: You need to look at the Eizo LCD. It's impressive.

I saw it at a trade show last year. They were displaying the classic black-to-white fade, and it looked perfect - no banding whatsoever. Same deal with color - it was sharp, bright, and vivid. Easily as good as any mid-high end CRT I've seen (and I've seen a lot of CRT's in the photo world). An absolute top-end CRT would probably be better, but not by much.

That said, the Eizo does cost the same amount as a used car :)

- Steve

rylan
27th August 2004, 07:02
I have looked at them. I design high end LCD monitors for work for the medical industry ;)

spadnos
27th August 2004, 09:12
Cool! Can you send me some? :D

Do you design the glass, the controllers, or both? (what company are you with, if I might ask?)

Do you do mostly color or B/W? It seems that a lot of medical stuff is aimed at replacing X-ray film, so it's black+white, but very high resolution.

- Steve

The PIT
27th August 2004, 09:48
Originally posted by rylan
I have looked at them. I design high end LCD monitors for work for the medical industry ;)


I'll test one for you if you like. :D

VJ
27th August 2004, 12:17
Hmm, it was a bit cheaper than my car though.. Price currently here is 700 Euro (for the one I linked to); I got it a bit cheaper though ;).

I chose it because it came out best in a number of tests... :)

Jörg

spadnos
27th August 2004, 14:14
Originally posted by VJ
Hmm, it was a bit cheaper than my car though.. Price currently here is 700 Euro (for the one I linked to); I got it a bit cheaper though ;).

I chose it because it came out best in a number of tests... :)

Jörg Oh - you got the crappy one :D

The one I was talking about is here:
http://www.eizo.com/products/graphics/cg18/index.asp

- Steve

rylan
27th August 2004, 18:08
Hehehe... I design the controler board that sits in the lcd monitor, and have worked on some specialized PCI-X cards to drive the monitors. Yeah the high end displays are greyscale. 1536x2048 and 2048x2560 with active DICOM curve calibration and backlight luminance monitoring.

Heiney
30th August 2004, 19:35
Do you guys see the future OLED technology helping color depth?

Still, something to be said for the prices and quality of today's CRTs........

rylan
31st August 2004, 05:36
OLED has a long way to go still before becoming an alternative to large format displays (by that I mean >15").

Kurt
20th September 2004, 03:19
Originally posted by VJ
Any idea what is meant with this:
http://www.eizo.com/products/lcd/l568/spec.asp
Display Colors: 16.77 million from a palette of 1.06 billion

The Pit:
I recently purchased this Eizo monitor, and it does seem to give superb quality for photoediting. It is currently configured to switch to sRGB (there is an appropriate icc profile) when any of my photo-editing softwares are launched. I haven't been able to verify how good colours match, though...


Jörg

That's the *regular* model ;)

VJ
20th September 2004, 05:43
I just checked: when you have a gradient, it isn't always smooth on the Eizo (depending on the start and end colours and the length of the gradient). Dragging that same image to my CRT monitor does yield a smooth gradient...

So, I guess this proves that CRTs still have better colour.
(but no, I'm not returning my Eizo, I love it!)

edit: My Parhelia is addressing them both at <s>16-bit</s> 32-bit, the Eizo is connected via DVI.


Jörg

az
20th September 2004, 06:07
16 bit? ARGH!

BTW, NEC-Mitsubishi are releasing a colour-proof LCD with an LED backlight, where you can tune the red, green, and blue backlight LEDs separately.

This 22" model could be yours for a mere 5k.

AZ

VJ
20th September 2004, 06:11
Oops, I meant 32 bit... :D


Jörg

VJ
29th September 2004, 07:23
Well, last update: my screen was in 16-bit :eek:
:ermm:

I set it to 32-bit, and the different steps of a gradient are no longer visible...
;)


Jörg