Colours washed-out on a TP600.

[SAE140]

This is a case of "Sod's Law" (aka Murphy's Law).

The sole purpose of acquiring a ThinkPad 600 was to run Tsunami '99: an electronic charting/ navigation program. Unfortunately, the secondary colours (browns, blue-greens) of the charts appear 'washed-out' - being of such thin 'water-colour' pastel shades that it's almost impossible to distinguish between the colours of land, sea and mud banks - especially when viewed in bright ambient light.

In contrast, the colours displayed by "C-Map ECS" (a similar but less capable program) on the same ThinkPad are bold and rich.

As yet another example of Sod's Law, the C-Map software even has a facility whereby the displayed colours can be user-defined, whereas Tsunami does not (!).

However, when either of these 2 programs are run on a range of other machines, including various desktops with PC-Chips on-board video/ S3 Video cards etc., and an ageing 486 Dell Latitude laptop I have, the displayed colours are good and are virtually identical - at least as far as I can tell by eye.

The latest NeoMagic MagicGraph 128XD driver from the Lenovo site has been installed on the Thinkpad (running WIN98SE), and I've played with Neomagic's Gamma-Correction facility which has had little effect.

I'm now plum out of ideas of how I might go about resolving this compatibility issue between Tsunami '99 and the Neomagic video system. As it's name suggests Tsunami is a 1999 program and no longer supported.

Has anyone else come across a similar problem and resolved it ?

Colin

[rkawakami]

The first thing that pops into my head is, "what's the TYPE number of your system?". You may have an HPA screen which could be the reason that the colours are as described. Also, what is the colour depth of the display (65K or 16.7M)?

[SAE140]

[quote="rkawakami"]The first thing that pops into my head is, "what's the TYPE number of your system?". You may have an HPA screen which could be the reason that the colours are as described. Also, what is the colour depth of the display (65K or 16.7M)?[/quote]

Hi

2645-850 - it's a 13.3" TFT, and I'm running on 1024x768 x256 colours. I'd like to try a minimum palette - say 16 colours or so, but this option isn't being offered.

What's throwing me on this problem is that the displayed colours of the program in question are ok on every other platform I've tried, and every program I've tried running on the 600 (with just this one exception ...) appear to be displayed perfectly ok. So the ThinkPad isn't 'faulty' and I'm assuming that this is a straight-forward matter of incompatibility between software and on-board graphics ?

I don't know if it's relevant, but the 600E and X have a colour management system - but not the 600. So - just out of interest, I tried installing the ThinkPad 600E .icm file - but it wouldn't install.

I'll keep working on it ...

Colin

[SAE140]

Ok - I've finally found the cause of the 'washed-out' colours problem.

Although this problem is apparent on just one chart display program - that's only because the palette being used is largely of pastel shades. And - when an 2ndry external crt monitor is plugged in - the colours displayed on the crt are fine. So it's an lcd display problem.

I then noticed that with the screen tilted further back, say 10-15 degrees - the pastel shades darken.

Now on this TP600 the horizontal viewing angle is fine - no significant colour changes from 15 degrees left or right. But the vertical viewing angle over the range +/- 15 degrees causes pastel shades to go from visible to completely invisible, although bold primary colours are still viewable.

Can I just check with you guys - is this normal functioning for a Thinkpad TFT screen ? My only other experience with TFT is an NEC desktop flatscreen which doesn't show this characteristic - although it has ccfl tubes at both top and bottom of the screen, unlike the Thinkpad which has just the one.

Is the plastic film in front of the LCD panel a polarising screen (?) and if so, would removing it improve things ?

Colin

[rkawakami]

TFT screens will act like that (vertical viewing angle shifts colours). For example, the 14.1" TFT SXGA+ running 16-bit colour (65K) on my T23 displays the pastel blue background on every other post on this site fairly lightly when viewed straight on. If I look downward upon the display, the blue tint disappears. Similarly, if I look upwards then the blue begins to darken, turning bluish-gray at about 45 degress.

You mentioned earlier about running 256 colours. Have you tried changing to the 16-bit (65,536) option? I'm assuming that for that old of a program they would have stuck to a standard, "web-safe", 256 colour palette. However, from my eyes, there's not too many "pastel" type shades in that palette. Maybe the choice of colours used in the program is causing the display to dither and you are seeing the result of that.

Don't know if you could remove anything from the display to make it look better, but I know that the screen can "yellow" from age or use of improper cleaning solutions. I've received a couple of Thinkpads from smokers and when the screen was cleaned, the cloth ended up brown.

[SAE140]

Hi Ray - firstly thanks for your comments - this kind of info proved very useful as I have no prior experience of laptop TFT displays to use as a reference.

You're right about the 256 colours - the legacy programs I'm using will ONLY work at 256 - for exactly the reason you mention.
Perhaps 'pastel' isn't the correct word to use: the problem is worse with a thin, pale light blue colour, and an equally pale 'avocado' colour - and also a pale nut-brown. Primary red, green, blue etc are fine, and show clearly through the 'wash'. (I'm now wondering if the program is displaying 'every other pixel' with white in-between, to create lighter shades ??)

Anyway - seeing as the TP itself is ok, and the screen isn't faulty (in the conventional sense of the word), I've been considering ways to overcome the limitation. Assuming that the darken-when-tilted-back effect is caused by the ccfl illumination coming only from below, I first considered mounting the TP upside-down and using a 180 degree screen rotation program, which would then enable darkening to occur in the 'right' screen tilt direction for my application - but I couldn't get the rotation program to work. Something to do with chipset limitations. It was a borderline barmy idea anyway.

I then hit on the idea of running two navigational programs simultaneously, each with it's own chart folio. Initially, this set-up was intended soley as a means of making a comparison between the displayed colours of an acceptable program and a 'faulty' one. But in practice this has turned out to be more than just a diagnostic procedure - it's actually an excellent way to use the Thinkpad as a navigational platform. I mention this here, just in case anyone else is thinking of doing the same.

With two nav programs (using two different chart folios) running simultaneously, it then becomes possible to instantly switch between them using Alt-Tab. Any ambiguous information from poor colour or folio inconsistences can easily and instantly be cross-referenced. But even better - it then becomes possible to view either a small-scale chart or a large-scale chart instantly at the press of a button. There's no longer any need to Zoom within a program, which requires multiple clicks or key-presses. So there are now effectively two pre-set Zoom levels on tap. Brilliant.

Although it's not essential to route GPS NMEA info to both programs, in practice it's convenient to do so, and this can easily be achieved by splitting the signal into virtual COM-ports using Franson's GPSGate.

A happy conclusion. I'll now apply myself to the task of reducing power consumption - but that will be the subject of another thread.

Colin
(Awaiting delivery of ANOTHER 600-series ... the bug has struck !)