Why Gateway only offer 18-bit color lcd? - Page 2

Gateway offers a 10% discount to AAA members. A few weeks ago, they also offered a $200 mail in rebate to match one being offered by Office Depot.

You forget about Dell's continuing effort to cut costs and keep cutting costs. That is what led them to outsource their technical support to India.

I tried this on my Gateway M505X. I set my screen to 800 x 600 with 32 bpp and then looked at the test images. The 24 bit one looks smooth and the 18 bit one looks like it is made of horizontal stripes. Is that what you see?

Excellent Summation CGameProgrammer!

My notebook display controls only provides for 16bit or 32bit selection. Even though the actual bit depth of the screen is 18bit, the fact that it is driven by a 32bit screen buffered display card places the apparent bit depth somewhere in-between, depending on any hardware tricks that may be used.
This is why current LCD screens aren't the best for any color-critical tasks such as color correction. For graphic designers, a CRT is still the best choice for that type of work. Plus, CRTs can be more accurately calibrated to specific output targets such as film, video or printing. For general tasks and gaming, I doubt most would even notice the difference.

The nice thing about many modern notebooks though, is that you can attach a CRT monitor as a secondary display for this type of work. Doing this makes the difference between 18-bit and full 32-bit capability apparent, particularly in color gradations where banding will be more visible in the lower bit-depth displays.

Regarding 24-bit vs. 32-bit, there typically is no visual difference since the main use of the additional 8 bits is for alpha channel info, for controlling transparency by applications that can make use of it. 18 bits (2^18) allows for 262,144 separate colors. A 24-bit (2^24) palette allows for up to 16+ million colors and a 32-bit (2^32) palette can provide for up to 4+ billion colors. For display purposes, the difference between 24 & 32 bit would be virtually indistinguishable due to display limitations in hardware. However, this difference is more critical for other output mediums, such as film, where the capability to resolve color depth is much broader.

I kind of assumed that there existed some LCDs that can display full 32-bits, meaning that they have 256 shades of transparency. I have never seen one. So perhaps, as CGameProgrammer said, they don't exist at all. But even then we are still left with three types of LCDs: 18bits, 18-bits with dithering, and true 24bits. The Gateway M505X must be a 18bit with dithering display, since Gateway claims the display to be both 18bits and 32bits. One can easily use those two red gradients to tell whether one's display is 18bits or 24bits. But the problem remains: can one tell the difference between a 18bit dithering display from a true 24bits display? The difference between those two is some 0.5 million colors. That is the problem with Dell, who claims their displays have 16.7 million colors, when in fact they have 16.2 million.

actually i went and got mine saturday (last day for 200 off for office depot) and i talked to the manager, and since office depot was 100 more, he just gave me 100 off, plus i found out that if you go to the store, the aaa card, only gives you 7% off not 10, even without the 100 off i got from the pricematch, it would still be a good deal, cause this laptop is great.

Except for those few who need true 32 bit color depth for their specialized applications (and they would not be using an LCD display anyway), I really don't think it matters. What matters to me is that my Gateway M505X is able to display a color depth of at least 24 bits. I don't really care how they manage to do it, nor do I think most other people would care either.

hey CGameProgrammer,

don't bother explaining.... I tried to explain this stuff in another thread but people still insist there are laptops with 32bit panels. They can't comprehend that 32bit color can be achieved from an 18bit panel and that any panel that can show 24bit color can, of course, technically show 32 bit color. Definitely do a search, because there is an entire thread where people are using an image of a gradient to help them discern whether their panel is an 18bit one showing 16.2million colors or a 24bit one showing 16.7 million colors. Its pretty entertaining. Well... actually slightly sad.

Anyway... I have to force myself to make this the last message I write about this, its like one of those subjects that always pop up like mac vs. pc.

But don't you think that consumers have a right to know whether their device have a true 24bit display, or a 18bit display with dithering? You can argue all you want about how the results of the two are so similar, and I agree. But no matter how perfected the technology is for 18bit displays to display 16.2 million colors, it still does not mean the display has 256 different shades of each color. Manufacturers such as Dell and Gateway are taking advantage of this loophole and are claiming their displays as 32bits. DOn't you think you have a right to know? Surely it is really difficult to tell the difference. It is impossible to use the gradient method. The point is, 18bit displays, though they can emulate 24bit displays, are fundamentally different from the true 24bit displays. I also know about the extra 8bits of a 32bit display being the alpha channel that the display ignore. There is no point in bring that up.

devast: You have to stop with your libel. The gradient was used to discern whether one's display can display 262,144 colors or 16.7 million colors. It was never meant to discern between 16.2 and 16.7 million colors. For that purpose it did its job well.

I started a new thread to show how 18bit displays are different from 24bit displays. Those interested click here.

Yes. On an 18-bit display the two will both look striped -- the 24-bit one should look just like the 18-bit one.

As has been said, there are no 32-bit screens, but companies like Gateway say there are just to avoid confusion -- otherwise people might think a 24-bit screen can't run in 32-bit mode or something.

All monitors are only capable of, at most, 256 shades of each color, and 256^3 = 16777216 colors = 24 bits (2^24) of color. It is possible to create a monitor with more range but there's really no point -- 256 is more than high enough.

Aah, you guys have just made it clear why my laptop's color reproduction has never looked like my desktops. Personally I noticed it right away as everything was a little washed out. Good to know that it occurs across the board.