Dell 2408 mini-review

[doddsy]

Yeah of course, I generally use 2 places for wallpapers:

SexyDesktop - The Worlds Sexiest Wallpapers for your desktop

and

InterfaceLIFT

[Tigger]

Well I was so impressed by the specs and other people's opinions that I decided to buy one as my first LCD. I've been a CRT die hard until now.

In many ways it is quite impressive, but, after setting up the screen as well as possible with the nvidia display optimisation wizzard I tested the screen with Passmark's Monitor test V3. I was very dissapointed to find what I would class as serious banding issues.

Blue gradient showing banding at the dark end


Red gradient showing banding at the dark end


Green gradient showing banding at the dark end


Gray gradient showing banding at the dark end


Closeup of gray gradient showing banding at the dark end


Am I being over critical? Are all LCDs this bad?

[toolsong]

That looks worse than it does on my 2005FPW

[Cov]

Have you spoken with your retailer yet ... would that be accepted as a fault at all ?

I'm not familiar with "banding issues" ... in what way is the day-to-day use affected ?

[Tigger]

I haven't spoken to the retailer yet. I wanted to thoroughly test the screen and see what other people thought before taking that route. I don't know whether the banding will be considered a defect or just normal for LCDs.

It's hardly ideal for displaying colours accurately and editing photos, especially since the high colour gamut is one of the biggest selling points! I've already noticed a slightly posterised effect in solid colours in photos.

Can anyone explain what is happening in the closeup? Their are hundreds of thin bands (256 levels?), but these are then grouped in to more obvious bands which at the left contain 3 thin bands, then moving right 4 bands then 5 then more, with the groups getting ever wider as you look further right. Anyone have a technical explanation of this?

[toolsong]

Read this new review of Hyundai W241D, suspect it has the same panel

bit-tech.net | Hyundai W241D 24'' widescreen monitor - Hyundai W241D 24" widescreen monitor

[nick_1]

I've just taken some photos of my 2408 to compare with but I don't see any major problems with banding until you very closely (see the left of the image below and you'll see ever so slight banding). The last time I looked into it LCDs still cannot do a full 32bit colour depth a CRT is capable of, that said this is the best LCD I've ever used.



Some more pictures in case its useful... compared to a Viewsonic VP201s





As this was the thread which convinced me to buy one I think its also worth mentioning that this is my second screen as the first one arrived slightly damaged and dell agreed to replace it (Picked up the old one at 11:00 on Friday and brought the replacement at 17:20. Well worth the 30 minute phone call to sort it

Nick

[Tigger]

Ooooohh!

I didn't expect that!

I've just updated the Nvidia drivers to the latest and it has made a huge difference to the banding issues I was seeing. I can still see some fine bands, but the problem is so much better now.

I've got an Nvidia 6800GS by the way, with the display connected via DVI, and set to 1920x1200 at 32bit colour. I was using forceware 93.71 (yeah about 2 years old, I know!) and have just updated to 169.21.

This is what my gradients look like now, showing just the left half of the screen as the bands are more obvious at the dark end. I've deliberately got the Dell logo in the picture so you can see exactly how much of the screen you are looking at.

Red


Green


Blue


Grey


Grey close up. You are seeing about 80mm of actual display width here (sorry about the map measuring ruler). The slight light and dark splodge in the middle is just a reflection.



So how do these images compare with people's expectations of colour gradients on LCD displays? Although I can still clearly see bands in the gradient, about 2mm wide, I think I might be able to live with these, unless anyone knows of another similar sized display which shows no banding at all?

[Cov]

TBH I didn't know what banding in regards to display problems means ... until I found a few interesting examples.

As far as I understand, a banding problem is when the shifting between two shades of a colour (between brighter & darker) at any point is rougher and more visible to the eye. The ideal condition would be an as smooth as possible shift instead of visible steps in blocks, is that right ?
Or is banding just an appearance of a vertical / horizontal dark line ?

Found a few interesting articles:

Scroll down the addeneum bit: Test of Dell 2407

Test samples for LCD screens

DELL 2407wfp-hc problem

Nice little showing off of the monitor:
Introduction de l'écran LCD Dell 2407WFP

[Cov]

Interesting info regarding LCD monitors:

TFT Central

LCD 24/7

[hibby]

2mm banding is the best you're going to get on a 24" monitor, if what I think holds true. Bear with me here:

It's an 8-bit panel, therefore can display a total of 2^8 shades of pure red/blue/green/grey. That means that it will show 256 different colours across the width of the screen in this particular test.

With a horizontal resolution of 1920, that's going to be bands every ~7.5 pixels.

From the specs, it has a dot pitch of 0.27mm. 7.5 x 0.27 = 2.025mm bands

Of course, you can't get a band 7.5 pixels wide, so it will probably be alternating bands of 8px and 7px wide.

[Bugbait]

On the other side, this clearly shows some good confidence of Dell & PcBuyIt in this product.

I had emailed the CS dpt of two main online stores in UK, a while ago, in regards to this problem. Here is what they replied:

As for the dead pixels we operate within the standard ISO standards for this product.

... and the other one said:
ALL TFT display adhere to the ISO specification which allows a certain limitation regarding stuck and dead TFT pixels and this can be viewed on the website.

I bought my Dell 2407 from PcBuyIt for this reason alone:

** DEAD PIXEL GUARANTEE - EXCLUSIVE TO PCBUYIT CUSTOMERS **
In the event your monitor has one or more dead / stuck pixels we will arrange to have the unit replaced next business day (call's must be made before 3pm to meet the next day deadline)

Had it since last year and still zero dead pixels. Unfortunately I was careless while cleaning it one day and scratched the screen! Time for a 2408 and the wife can have the 2407 reject....