On 1/14/2014 2:27 PM, Tina Manley wrote:
> I'm scanning at 4000 dpi, the highest actual dpi of the LS5000. My scans
> end up about 150MB. I reprocess them through Vuescan for the filtering,
> especially Digital ICE or Vuescan's infrared cleaning, saved as DNG, and
> the size is reduced to about 110MB.
On 1/14/2014 2:53 PM, Jon Mitchell wrote:
> ... My experiments seem to show that when you ask VueScan to
> save the file as RAW, it saves this as a TIF anyway - so what is the
> difference in just saving it as TIF (assuming I leave all the Colour &
> Filter settings alone) ? Is the "RAW" TIF, as the name implies, just the
> RAW data from the scanner - but the non-RAW TIF has had some adjustments
> done ?
OK, folks, easy there, it all makes sense.
When you ask VS to save as RAW, it sames not three, but four channels, RGB plus
IR.The data is saved as linear scanner
output, without applying gamma correction or any other adjustments.
The files are ordinary TIFFs in format, but look very dark until gamma
corrected and they contain that fourth channel.
That, Tina is why your DNG output files from reprocessing VS RAW files for IR
and other adjustments are smaller, they
become only three channel, not from some inherent efficiency of DNG.
My 4000 dpi scan RAW TIFFs are mostly in the 160 MB range, and the TIFF
finished scans about 120 MB.
Unless I'm just scanning a couple of frames, I always scan to RAW. That
requires no real attention, but the scanning is
very time consuming. I can just set it going and do other things. Once I have
the RAW files, I 'scan' them in VS,
setting exposure, white and black points, etc. and applying dust and scratch
removal.
If one doesn't come out quite right, 'scanning' it again only takes moments,
not minutes, as with a physical rescan.
Depending on one's available storage and OCD rating, the RAW files may be
deleted after processing. I tend to keep them
until I have finished all processing of the images in PS.
Scanning For Moose
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What if the Hokey Pokey *IS* what it's all about?
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