imac second monitor - how many colours?

I am thinking of buying a used 2 yr old imac aluminium 20" which I believe displays thousands of colours, 6 bit. If I used a second monitor with it, how many colours would it display? Is the limitation of the imac in its screen or is it that the computer itself can not display millions of colours? I know it uses dithering to simulate millions but that's cheating! thanks for your thoughts, Alan

alan8657 said:

I am thinking of buying a used 2 yr old imac aluminium 20" which I believe displays thousands of colours, 6 bit. If I used a second monitor with it, how many colours would it display? Is the limitation of the imac in its screen or is it that the computer itself can not display millions of colours? I know it uses dithering to simulate millions but that's cheating! thanks for your thoughts, Alan

Click to expand...

I'm not sure where you are getting all of this inaccurate information...but:

- 6 bit color is 64 colors
- 8 bit color is 256 colors
- 16 bit color is 65536 colors
- 24 bit color is millions of colors

I am quite sure that a 2 year old iMac is capable of displaying millions of colors on both the built in monitor & the secondary external monitor (assuming we are not talking about a "humongous" external display).

Also...the video card on a 2 year-old iMac has about 256 meg of video memory...I really do not think that the Mac needs to "simulate" millions of colors.

Hope this helps,

- Nick

Hi Nick, thanks for your reply, sorry if I am confused over bit depth no's, but I have read in other forums and eslwhere about the 20" imac having a cheaper screen that can only display thousonds of colours and about apple being sued over their advertising for it:

Los Angeles (CA) - If you’re going to say that your displays can show millions of colors, you better be able to back that up. That’s the lesson Apple is learning after Los Angeles law firm Kabateck Brown Kellner filed a lawsuit against the company for false advertising.

Part of Apple’s ad campaign for its iMac computers was that they could display "millions of colors at all resolutions." According to the lawsuit, however, there are really only 262,144 colors.

But my concern is how many colours would an average, say 20" external screen display when connected to the imac?

thanks, Alan

alan8657 said:

Los Angeles (CA) - If you’re going to say that your displays can show millions of colors, you better be able to back that up. That’s the lesson Apple is learning after Los Angeles law firm Kabateck Brown Kellner filed a lawsuit against the company for false advertising.

Part of Apple’s ad campaign for its iMac computers was that they could display "millions of colors at all resolutions." According to the lawsuit, however, there are really only 262,144 colors.

Click to expand...

Hi Alan. Do you have a link to this story ??? Sounds very interesting.

Cheers