Re: Highest Resolution RGB Drum Scanner
Re: Highest Resolution RGB Drum Scanner
- Subject: Re: Highest Resolution RGB Drum Scanner
- From: Andrew Rodney <email@hidden>
- Date: Fri, 31 Aug 2001 18:59:54 -0600
on 8/31/01 6:37 PM, Randy Wright at email@hidden wrote:
>
In my opinion, it is not the manner in which the film
>
is supported for scanning that distinguishes a drum
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scanner from a flatbed. The vast majority of drum
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scanners use a PMT sensor that samples a single pixel
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at a time.
True, there are non PMT scanners however. A drum scanner is a scanner that
uses a drum to rotate the film, placing a very fixed point on the film in
focus. A PMT scanner is a PMT scanner. A drum scanner is a drum scanner.
There are some disadvantages to PMT scanners. The reason negs scan better is
the point source of the PMT is very harsh and negs generally scan poorly
unless the user has a lot of control over the aperture of the the scanner
and can do a whole lot of testing to find the best settings. PMT's do
capture a pixel at a time. CCD's suffer from blooming since the sensors are
close to each other and there is some spill that can "contaminate adjacent
pixels. But CCDs are a whole lot better then they were years ago when the
only solution to high quality scans was a PMT. PMT's are pretty old
technology! They have as many advantages as they do disadvantages.
I will take a good CCD scanner (a drum like the Imacon) any day over a PMT
that doesn't allow me to turn off the on the fly conversions to CMYK or
don't provide software that is ICC savvy. I'll take a scanner that produces
full rez USM previews in the scanning software over a PMT that doesn't.
I ran a ScanMate 5000 for a few years. It was a great scanner when it wasn't
breaking down or I wasn't cleaning gel off my film. I would have to say that
it probably produced marginally better quality than the same scan off a
Flextight but the differences were so slight you'd never see it on output. I
happily replaced the ScanMate for the original Flextight (two generations
ago) and I haven't regretted it at all.
>
The
>
reason a drum is used is to move the image past the
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sensor as quickly as possible, to get the scan done in
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a reasonable amount of time. In this context, the
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Imacon has more in common with a flatbed than a drum
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scanner.
I don't agree. I've worked with some VERY high end flatbed scanners
(EverSmart Supreme, Agfa Select Scan, Lino Topaz and recently the Fuji
Finescan). The Imacon is faster at preview and scanning (the new Flextight
III is ever faster). The Flextight moves the film past the optics JUST like
a PMT drum scanner, it's just not using a PMT. The Flextight is a CCD drum
scanner.
>
My question for Andrew is: In what way is a CCD better
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for scanning negs than a drum/PMT?
You answered below:
>
In terms of results, the difference between
>
the two is similar to the difference between condenser
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and diffusion photographic enlargers. The former will
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provide maximum contrast and detail, including detail
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in surface defects on the film. The latter will hide
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the defects, for the price of a little less contrast.
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Either can be used successfully.
The software is also VERY good at dealing with color negs. It does a very
good job of inverting the neg and removing the orange mask. It has a cool
"reduce grain" option it it's USM settings that does a very nice job (when
set properly) on color negs.
Andrew Rodney