Surely this can't be right?

Salohcin · 6 Jan 2009 at 01:27

Comparing an Apple 30" HD cinema display with a Dell 30" (from my limited knowledge of the specs, they're generally even otherwise), the Dell apparently has a contrast ratio of 3,000:1, whereas the Apple has 700:1.

Considering how close they apparently are in other areas, this huge difference doesn't make sense. What am I missing here?

Edit: Just noticed that Apple lists it as the 'contrast ratio' only, whereas Dell lists it as 'dynamic contrast ratio' - are they different things??

Theguy · 6 Jan 2009 at 02:45

dont quote me on this, but I have a feeling the dell is from grey to grey, where the apple is black to black..

ecat · 6 Jan 2009 at 07:27

Contrast ratio: often the difference in light levels between a full black screen and full white screen expressed as light level divided by dark level.

LCD's are not very good at displaying black, there is always some light passing from the normally always on back light through the LCD panel itself.

dynamic contrast ratio is a truly horrible marketing ploy, at least the way it's currently implemented. Roughly speaking, if the display image is mostly dark the back light is automatically dimmed brightening again if the image lightens. Sounds an ok idea? It could be if applied to small areas of the screen but with current technology the best that can be achieved is fairly large horizontal strips, though more often the dimming appears to affect the entire screen. This may be ok for film and games but imagine you have a dark desktop (back light is low), now open a 3/4 full screen white Google search page - the whole screen changes in brightness, I find it impossible to use for either work or games ! The main advantage of this dimming of the back light is the measured level of a black screen is much darker allowing manufacturers to quote a much higher contrast ratio.

I'd advise you to ignore all dynamic contrast ratio figures and look only at the normal, lesser, true contrast ratio usually a figure between 600 and 1200 for current consumer LCD's.

philjohn · 6 Jan 2009 at 08:59

As ecat said, horrible marketing ploy. The best you'll get on an IPS screen such as the ACD's, Dell, HP or Hazro is 700:1 - 800:1.

Contrary to what monitor marketing departmens would have you believe, this is plenty.

Egosh · 6 Jan 2009 at 09:12

the apple is has an ips panel as far as im aware (not sure about the dell)...and you have to remember that apple products arent exactly priced very competitively..

philjohn · 6 Jan 2009 at 09:15

Dell 30" is also an IPS (only PVA and IPS available in that size currently). The Dell has a more recent IPS panel, but it's wide-gamut as well which may not be the OP's cup of tea.

As far as apple being competetively priced, their new 24" LED ACD is definitely cheap for what you are getting (although the glossy screen gets a black mark in my book).