> After re-reading it, it looks like you're thinking of
> scanning, is that correct?
You can relate it to scanning if you like, but a digital image is a digital
image, there are just different compression formats, ie JPEG, TIFF, etc.
It's the same whether you scan or take it straight from the CCD of a digital
camera.
We're trying to go from electronic storage to a physical image,
not the other way around.
It doesn't matter which way you go, a pixel is a pixel, the more ORIGINAL
pixels you have, the better quality the image will be. A 300 dpi picture
will be very grainy if you try to go 4x6.
In your photo rendering program, (ie Photoshop) when you increase picture
size, let the program set the dpi, or vice versa. Or you can increase dpi
without increasing size. Increases clarity somewhat even if the quality
isn't really any better. If you are scanning a film based photo, scan your
original image at the highest resolution possible. Then you can take the
digital image and manipulate it much easier with higher quality. I never
scan at less than 600 dpi. It would help if I had a modern scanner.
A digital camera is basically a scan of the live object. The higher the
resolution (ie 2.5 megapixels vs. 1.5 megapixels) results in a higher
quality print.
Film based pictures are the same way. A slow film (ASA/ISO 100) has a higher
resolution (more pixels, or dpi) than ASA/ISO 800. Notice how the faster the
film the grainier the image becomes? That's because to make the film more
sensitive to light, the siver halide grains must be larger. You can't blow
up an image of fast film as large as one from slower fim. that's why slides
are super clear-they are quite slow, such as ASA/ISO 64.
yet film based pictures are at a MUCH higher resolution than digital. The
average consumer digital camera is 2-4 megapixel. The average film picture
is at least 10 times that. And it's getting better, just like digital.
Trouble is, it's already so good, we can't tell.
We're talking about a raster image here, not a newspaper-style
image made up of discrete ink drops.
Unfortunately, you ARE talking about individual ink drops. When you tell the
computer to print the image from, what does the printer do? Print ink drops.
The smaller the drops, the better the image. You are limited to the quality
of your printer no matter how good your image is.
I'm getting long winded here, so I will leave it at this: experiment a bit
with your photo rendering software and printer and see what happens and what
you like. Once you find what works best on your printer, it's a breeze.
Oh-I work in the photo industry, in a photo lab building and repairing
cameras, printers and scanners and we take digital images, print them to
film, then process them in the normal fashion (C-41) along with straight
digitally printed and straight film based images.
HTH, and if you have any questions feel free to hit me off list.
Maybe you can send me an image and I can play with it a bit. This could be
fun!
Jon
STL MO
This archive was generated by hypermail 2b29 : Fri Feb 06 2004 - 11:48:14 EST