Digital BW, The Print

You said:
<<So this article might make us ponder why it is that we think we must routinely scan a 
photograph at
(maximum ppi)? We can't show that size on our monitor. Our printers cannot
print that much resolution. The photograph doesn't have that much detail
anyway. Our memory size doesn't tolerate it and our disk space hurts too. It
must be a macho thing to do it.">>
And you forgot to say..."and the scanner does not really scan at that resolution either. 
4870 is an illusion made up of cloned pixels not of pixels directly out the optics. This 
one bit of data has everyone dreaming macho and consuming tons of RAM and patience. 
Fortunately in B&W you divide by 3, lucky.  Your eyes will not fool you though, follow 
them and you will make the best of it.

      1. Re: Computing power
           From: "B. Campbell" <bellis60@...>


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Message: 1
   Date: Mon, 6 Dec 2004 18:22:17 -0500
   From: "B. Campbell" <bellis60@...>
Subject: Re: Computing power

>If you scan at a reduced resolution eg. 1200ppi instead of 4800ppi
(assuming
>that is the optical resolution), your scanner simply throws away
>three-quarters of the detail in your film, leaving you with just
one-quarter
>of the original detail.

I thought that ppi in the scan was relevant in determining the amount of
"detail" in the print but that detail in the scan was a function of the
scanner's optics and mechanics, not the ppi setting. I would expect to lose
detail in the print if for example I scan a 4x5 negative at 300 ppi and then
make a 16x20 print but I never thought that if the scanner is capable of say
4800 ppi and I scan at 1200 ppi I've necessarily lost  three quarters of the
"original detail" in the negative regardless of the size at which I print.
Or stated another way, I would have thought I could scan the 4x5 negative at
say 720 ppi with a 4800 ppi scanner and make a 4x5 print that has as much
detail as the scanner, printer, and paper are capable of producing, i.e.
that I wouldn't lose most of the detail in the negative by doing that.

"Printer drivers vary but probably you don't need to help it resample by
scanning larger than is reasonable. The (maximum ppi) will consume vast
amounts of memory for no good reason. . . So this article might make us
ponder why it is that we think we must routinely scan a photograph at
(maximum ppi)? We can't show that size on our monitor. Our printers cannot
print that much resolution. The photograph doesn't have that much detail
anyway. Our memory size doesn't tolerate it and our disk space hurts too. It
must be a macho thing to do it." Fulton, "A Few Scanning Tips," pp. 49 & 54.

However, I'm certainly open to being corrected, I don't claim to be an
expert. I just haven't before heard that the scan (as opposed to the print)
loses detail as the ppi is reduced below the maximum of which the scanner is
capable.