> My 15 inch Powerbook (Aluminium = DVI out) has no trouble running a
> Cinema display at it's native 1280 x 1024. That's not the native rez of
> the powerbook. I tried a 12 inch Powerbook (Aluminium = DVI out) on a
> 20 inch Cinema at our seminar at Apple last year, that was fine too.

The basic difference between an LCD/TFT and CRT is that the LCD consists of
a matrix of explicit pixels. An iBook's internal display is a matrix of
1024x768 pixels, 786,432 in total, or a bit under a megapixel. This is its
"native" resolution.

To display 800x600 pixels the display must interpolate 1024 into 800 on the
long side, 768 into 600 on the short side. This involves anti-aliasing,
which we know is another name for blurring. You'll see no sharp edges under
these conditions.

With a CRT, its dot pitch doesn't translate to an exact number of pixels.
Consequently it's possible to change the scanning geometry of the guns to
display more or less "pixels" on the screen without changing its apparent
"sharpness".

As far as a PowerBook or iBook driving different-sized screens is concerned,
this is a factor of the amount of memory on its video card. The more memory,
the larger the external screen it can drive at full colour depth. The more
recent the machine, the more video memory it's likely to have. The video
card's memory amount can be found using Apple System Profiler.
 
> I'd have to say I'm not positive that an iBook can do it as it's only
> got VGA out, so needs a special adaptor to use the Apple LCD/TFT
> Displays. I'd have expected it to work OK with a <VGA input> TFT though.

That's true, although you can find VGA to DVI and ADC adapters at the Apple
Store. The major difference is that a PowerBook can do monitor "spanning":
i.e. the external and internal screens can be set to display different
images, giving the increase in desktop space of a true 2-monitor system,
whereas out of the box the iBook can only do monitor "mirroring", each
screen displaying the same image. Unsupported hacks can be found on
versiontracker.com to enable monitor spanning on an iBook. Apply these hacks
at your own risk.

Being a cheapskate I use my 12" 1Ghz PowerBook for everything. At my desk I
attach it in spanning mode to a 17" CRT monitor set to 1280x960, which it
drives perfectly happily, plus I get the PowerBook screen for PSCS palettes.
It works for me.

Best regards

Paul Ellis

Mamatus Limited | http://www.mamatus.com
Photography - Interactive Imaging - Apple Macintosh consultancy
Tel +44 20 8341 9788 Mobile +44 7930 312554

Member of The Association of Photographers

===============================================================
GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE

Reply via email to