5 Jul
2011
5 Jul
'11
5:08 p.m.
----- Original Message -----
From: "Pete Turnbull" <pete at dunnington.plus.com>
To:
"General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Sent:
Tuesday, July 05, 2011 9:03 AM
Subject: Re: Photographing fiche (Was: DEC
RD53 Manual
awfully high-res sensor to do that!? Back-of-envelope
arithmetic:
3,216,000,000 pixels.? Thats 3216 megapixels.
On 05/07/2011 07:50, Dave Caroline
wrote:
>>>> I don't think you need higher
resolution, just more
magnification.
>> More magnification can
make it
feasable to photograph one frame of the
>> fiche at a
time.
>> Higher resolution may make it feasable to
photograph the
entire fiche
card
> at once.
You'd need an If you want something equivalent to scanning a 10.5x8
page
at 400dpi,
you need 3200 pixels across a (portrait) page.
The
1978 BA11-K fiche I have in front of me is a low-magnification (by
DEC
standards one, and it's 16 pages
across, but they're landscape
format
pages, so that works out to 10.5 x 400 x
16 = 67,000 pixels wide,
and
therefore the sensor would have to be about
67,000 x 48,000 =
The 1987 Bulletin fiche I
have in front of me
is 25 (portrait) pages
across.? 400dpi x 8" x 25 =
80,000, which
is even worse.
Even if you accepted 100dpi, you still end
up
needing a sensor of about
200 megapixels.
Would the
hubble telescope do? I assume it's digital because it makes it
quicker to get
images from it, and if it was film-based the film would have
to be huge,
right?
Regards,
Andrew B
aliensrcooluk at yahoo.co.uk