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John Conway
9-Feb-2012, 16:02
Could someone kindly explain how the scanning process works? What I mean is, how does the scanned negative become a finished digital print. Is it basically the same as a conventional enlarger except it is done through electronics with the scanned negative and printer? I have scanned prints. But I have not yet scanned a negative.

Peter De Smidt
9-Feb-2012, 16:18
Scanning the negative with a film scanner gives you a digital file. Edit file, i.e. use Photoshop or similar to adjust the file to taste. Print the file. It sounds easy, but the devil is in the details, just as it is with traditional darkroom work.

Randy
9-Feb-2012, 18:56
Scan a negative (software converts it from neg to positive), do some processing in Photoshop (adjust brightness, contrast, sharpness) crop, resize, dust removal, then print on your own inkjet printer, or send it out to a lab...and still be disappointed with the final print :(

Bruce Watson
10-Feb-2012, 07:19
Could someone kindly explain how the scanning process works? What I mean is, how does the scanned negative become a finished digital print.

There's whole books on the process. For example, Mastering Digital Black and White (http://www.amazon.com/Mastering-Digital-Black-Black-White/dp/1598633759) by Amadou Diallo. Tell you everything you want to know.

unixrevolution
10-Feb-2012, 07:38
I currently don't have a dark room or the space/money to set one up, so I am left with the alternative of lab development and digital workflow. I typically scan a slide or negative at 2400-4800 DPI depending on my maximum anticipated enlargement, then edit in PS and print on an Epson 1400 for 13x19 and smaller, or send to a photo finishing place for anything bigger. It's still very much trial and error, especially since Epsons can't seem to print black and white with any neutrality unless you jump through hoops, but the results so far are encouraging, espeically with color.

Lenny Eiger
10-Feb-2012, 14:32
Could someone kindly explain how the scanning process works? What I mean is, how does the scanned negative become a finished digital print. Is it basically the same as a conventional enlarger except it is done through electronics with the scanned negative and printer? I have scanned prints. But I have not yet scanned a negative.

I thought about this for a while before it became clear. I use a drum scanner. Scanning a neg or a chrome is the same to me. I simply set a different profile, and in both cases I work with a positive on the screen.

What the scanner does is select a spot (a very small spot) on the negative and read it. It is not a pixel, it isn't an image. Its a number, or more specifically, 3 numbers, one for each channel of Red, Green and Blue. Thankfully we don't have to read the number on each of 320 million pixels, like Neo reading the Matrix. Photoshop shows us the resulting numbers as pixels.

Then, as Peter suggested, one adjusts the image to taste, using curves and adjustment layers and then prints it out. Printers understand numbers and turn them into mixtures of ink droplets that we see as distinct colors.

I hope this answers your question... or helps to.

Lenny

John Conway
10-Feb-2012, 15:20
Wow, there is a lot going on with the scanning process. Very interesting.

Sideshow Bob
10-Feb-2012, 16:49
I don't know if this will help or cause more confusion but this is the optical path of a ScanMate drum scanner. The synopsis is if you are scanning a piece of film, a bright light from the light tube passes through the drum and film into the sensor. In the sensor the light is split into three analog signals, blue green and red, which is then sent to three Photo Multiplier Tubes (PMT's). The output of the PMT's (analog signal) is amplified and converted from an analog signal to a digital signal which is then processed but the scanner (black magic) and sent, by a cable, to your computer as a digital image file.
This is a VERY simplified description of how a drum scanner operates and there is a lot is going on in the scanner that I've skipped over but hopefully I didn't simplify it too much. :-)

Gale

http://i1085.photobucket.com/albums/j440/MrGale69/Scanner-Diagram.jpg

tgtaylor
11-Feb-2012, 23:46
The first thing to do is to create a profile for your monitor. I use the Monaco Optix colorimeterbut there are newer (and more expensive) alternatives. With the monitor profiled I then create a profile for both the scanner and the printer using the Monaco software for both reflective (prints) and transparencies. For the former it is necessary to create a seperate profile for each type of paper you will be scanning. For example, Epson Premium Glossy, Premium Semi-Glossy...etc. Once that is completed you run a test print to see if the print matches what you scanned and see on the monitor. I just finished re-profiling my scanner and printer and here is the result:

http://farm8.staticflickr.com/7203/6860846313_a0dc07bcf2_b.jpg

The colors on the print are extremely close if not identical to what I see on my monitor. The only exception is the sky which appears a tad lighter in the print.

That's all there is to it. :)

Thomas

John Conway
12-Feb-2012, 20:48
That is one fine looking image.

tgtaylor
13-Feb-2012, 11:18
Thanks John. I like it also.

After having exhausted all the old ink from 2004 in my printer, I decided to re-profile the printer and scanner and arbitrarily selected the above from a file containing about 75 Gepe AN mounted 6x7 slides to run a test print. Somewhere I have another shot of this scene with "better" clouds in it but at the time I was only interested in confirming that the slide looked like the image on the monitor which in turn looked like the resulting print the above was good enough. It makes a handsome print though, one worthy of framing.

Thomas

John Flavell
14-Feb-2012, 14:53
I found this helpful when trying to understand a bit more about the process:

http://www.kenleegallery.com/html/tech/index.php

buggz
15-Feb-2012, 13:02
Good information on that link, thanks!


I found this helpful when trying to understand a bit more about the process:

http://www.kenleegallery.com/html/tech/index.php