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  #1  
Old 05-21-2011, 07:40 AM
robert23 robert23 is offline
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Scanners

I would be very interested to know peoples views of what is the best scanner, Type -- Model for use on Photograph colour prints that have been produced on photographic print paper, from negative film.
The objective to be able to capture the maximum amount of information from the photograph print.
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Old 05-23-2011, 09:21 AM
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Re: Scanners

Print scanners don’t require a lot of horsepower like a good film scanner. By the time a print is made, you’ve lost a ton of data hence, the best quality is to scan the film. But since you say print scanner, I can say that the Epson V750 is quite a nice unit for prints (it can scan film too but its not on par with a really good drum scanner which is designed to capture every ounce of data from a film original). The scanning software is also key. SilverFast is a very powerful scanning driver which is optional with the Epson. This product drives lots and lots of scanners!
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Old 05-23-2011, 08:09 PM
robert23 robert23 is offline
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Re: Scanners

Dear Andrew
Thankyou for your reply and advice.

Yes I have trialled the Epson V750.
Unfortunately I do not have access to the negative film, which no doubt would provide a lot of answers to my quest, but this no doubt is the reason it is being refused me.
As well as the Epson I have trialled a good many other types and model of scanner.
The Epson measured up very well in the comparison.

While I have your attention could I please ask some more advice or opinion.

The photograph prints that are subject to my endeavour, appear to have been altered from the original image.
This appears to have been in a number of ways.
The principle change being by the addition of detail to the image --by what appears to be information taken from another photograph, by photographing that photograph, then multiple exposure --sandwhiched negatives most likely--with the original main image negative.
It appears that image was then --artistically adjusted to disguise the edge effect of the added image, as well as to camoflage some other content in the original image.

I have located the print used for the second --superimposed image-- so there is little doubt image has been added, but I am still trying to determine --just how it was added-, but it would appear to me by the method I have outlined.

As well as using scanners, a 15 megapixel Kodak camera has been used, the comparison of information obtained by each scanner and camera being quite interesting.

It would be very interesting to have any comment made to assist me in further quest of obtaining the maximum information from the content of the final photograph print and any thoughts which may guide me to interpret what method of combining the images was most likely used.

Thanks again for your advice,

Robert
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Old 05-24-2011, 08:42 AM
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Re: Scanners

A scanner is a true RGB capture device. A DSLR isn’t (it produces interpolated color). On a scanner, there is a trilinear CCD that moves across the item producing true color for red, green and blue. There’s no need to render raw data (demosaic the data) where with a DSLR there is a need because its not scanning the scene, its using a single capture sensor with alternating filters over the sensor.
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Old 05-24-2011, 06:47 PM
robert23 robert23 is offline
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Re: Scanners

Dear Andrew

Considering the two different type of information capture, with the same subject, a fixed image in a photograph print, (although obviously with different lighting of the subject photograph print), could you please tell me the most likely differences to be observed in the captured, (scanned), (photographed), images.

thankyou

Robert
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Old 05-24-2011, 06:56 PM
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Re: Scanners

Well if you look at what demosaicing does, I think you’ll see the ‘issues’ compared to a true RGB capture:

http://en.wikipedia.org/wiki/Demosaicing

The ‘Christmas tree’ effect is one of the downsides to a single capture sensor. The article above shows this (Reconstructed).
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