Garth Wood wrote:
>
> Well, looking over the posts which brim over with enthusiasm for the idea of
> an electronically-distributed (assumedly, via the 'Net) Olympus Calendar, I
> got to thinking: just how big would this sucker be, in file size(s)?
> Here's some quick back-of-the-envelope calculations:
>
> If the assembled personages of this august list wanted to have 2450 dpi
> output (Lino, gives approx. 133 lpi [good magazine quality]), the following
> would hold.
>
> Image Size: 8" x 10" (for example)
> Bits per square inch: 2450 x 2450 = 6,002,500
> Square inches in image: 80
> Size of image file (ignoring overhead, monochrome):
> 80 x 6,002,500 = 480,200,000 bits
> = 60,025,000 bytes
> = 57.24 Mbytes
> Size of image file (CMYK): 4 x 57.24 Mbytes = 228.98 Mbytes
>
> Download speed using a 28.8 modem dialup with 97 0.000000e+00fficiency
> (27,936 bps):
> (480,200,000 x 4) / 27,936 = 68,757 seconds
> = 19.1 hours (approx.)
>
> That's for *one* image, folks. If you drop the dpi (you no longer have
> display-quality on paper, although a good dye-sub printer could fake a lot
> because it does continuous-tone gradations), you get the following results:
snip...
> Thoughts?
You´re joking...
Do you have images 228 MB big? Zuiko produce sharp images, but not as
sharp as to justify 228 megs scans! Not to mention the film.
Just calculate: Your image is roughly 8 times enlarged, that means you
have to scan your negativs, positivs with 8 x 2540dpi = 20320dpi!!!!
Never heard of a scanner capable of this.
The resolution of your Zuiko image should should be roughly 400 lines
per mm to justify this.
What you have done, is to confuse the resolution in dpi of the printer
with the halftone resolution of the image.
The printer needs for his press a higher printing resolution to simulate
halftones.
If you want a 300 dpi or 150 lpi resolution for your image 8 x 10 you
have to calculate:
8X10=80 square inch
300x300=90,000 pixel
90000x800=7,200,000 image pixel
each pixel has 3 byts 24 bit, because you should not separate in CMYK
before you know your printing device to match. Without Postscript and
just Mac or Windows OS it´s futile to separate images because this OS
only know RGB colors.
7,200,000pixel x 3 byte = 21,600,000 byte or roughly 20 MB
20 MB is still a impressive size for one image. The grid is a PS vector
file which counts not much.
Richard
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