Re: I have a 30mp camera redux


"John Adams" <no@xxxxxxxxxxxxx> wrote in message
news:fyi0j.15513$HU1.11568@xxxxxxxxxxxxxxxxxxxxxxxxx
Those of you saying my slides will be mush if I scan them at 4800DPI are
clueless. Scanning film and slides DPI depends on the size one intends to
print at. For a very large print size scanning film and slides at 2400 or
even 4800DPI is the correct way to do it. You bozos had no idea what the
slide scan was for or intended print size so you were talking out of your
arse. Oh, and working at a high end printers doing limited edition prints
is a lot different than printing photos in magazines so of course they
will scan at a much higher DPI, all depends on the final print size
needed. Limited edition prints are much larger than images in a magazine.

ROFL

BTW, I went and bought an Oly E510 a few days ago so welcome me to the
group. I ain't going any where any time soon so get used to it. :)

Damn, the laughs just keep coming! What this has to do with scanning though
I can only guess! Perhaps this should have gone at the end.

http://www.scantips.com/basics13.html

For example, a full frame 35 mm color negative scanned at 2400 dpi will be
about 3400x2200 pixels, and about 22 megabytes. Scanning at 2400 dpi and
printing at 300 dpi allows enlarging that printed image 8 times more than
the original film size (2400/300 = 8). Scaling by 8, so that the 1.4 x 0.9
inch film size (36 x 24 mm) prints 8X larger gives 11.2 x 7.2 inches. It
will look great in regard to detail if printed at 200 to 300 dpi (assuming
the printer can handle it). Scanning film originals can support this
level of detail. Scanning a 6x4 inch photo will not.

Let's quickly review scaling again, to make the point about large images,
and to make sure the simple arithmetic is understood. The basic fact is
that dpi means "pixels per inch". The main point is that the image size in
inches is computed from the image size in pixels, using resolution to
space those pixels on paper.

The ratio of (scanning resolution / printing resolution) gives the
enlargement factor. If scanning at 2700 dpi, and printing at 240 dpi, then
the printed image is 2700/240 = 11.2 times larger than the original film.
We can adjust the printed size by varying the printing resolution, maybe
200 or 300 dpi instead of 240 dpi.

Saying the same thing another way to make sure it is clear: If we scan 1.4
inches of 35 mm film at 2700 dpi, then we get (1.4 inches x 2700 dpi) =
3780 pixels. If we print 3780 pixels at 240 dpi on paper, then that image
size is (3780 pixels / 240 dpi) = 15.7 inches. 15.7 inches is 11.2 times
larger than 1.4 inches. Large images in pixels are needed to print large
images in inches.

For example, to print 8x10 inches at 240 dpi requires (8 inches x 240 dpi)
x (10 inches x 240 dpi) = 1920 x 2400 pixels. It takes (1920 pixels / 0.9
inches) = 2135 dpi to create this image from 35 mm film (full frame, so
even more if it is cropped).

We do need large images to print large at high scaled resolution. Film
scanners will give us those large images while retaining very good image
quality.

Good for you and how are the prints coming out?


.

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  • I have a 30mp camera redux
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