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kasey wertheim
Posted on Friday, May 30, 2003 - 06:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Uri,

Show me the print. :)

Seriously, it depends on the quality and quantity of detail in the image. By telling me you are capturing an image of friction ridge skin at 300 ppi, you are telling me that the quality of the image is low but the quantity is high. Examiners like to see at least 500 ppi for a large area of print, and 1000 ppi or higher for smaller areas. I hope this helps in whatever you are trying to accomplish. (??)
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Uri Rubin
Posted on Thursday, May 29, 2003 - 09:52 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hi
I would like to know if scanning the hand in 300dpi and than editing that in photoshop for example will give sufficint infornation for a FP expert

Thanks

Uri
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Steve Scarborough
Posted on Monday, February 25, 2002 - 02:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Duane,
Like Kasey, we also use the Codonics here in Las Vegas. We use the process he described to come up with 1:1 prints. Use a scale, with the measure tool block out a distance in the print and crop to that distance. Then resize image to the size. While resizing change resolution to the print resolution of your printer.
We have also found that one some prints are a bit fuzzy on the Codonics. We also use an Olympus P-330 digital printer. It is also dye-sub technology and if you tweak the settings a bit will produce comparable quality 1:1 prints of latents. The Olympus' 3x4 prints are perfect for everyday prints of scanned, enhanced latents for entry into AFIS.
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Kasey Wertheim
Posted on Thursday, January 31, 2002 - 10:55 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Duane,

At the Mississippi Crime Laboratory, we use Codonics dye-sublimation printers for high-quality 1:1 output. Kodak, I believe, is the manufacturer, and sells under both names. ?? Anyway, the scaling process is actually fairly easy if you make sure to capture a scale with every image. One trick is to capture the scale at a 90 degree angle so when you box off your image and crop, it is parallel to the ruler. This helps get an exact size.

To re-scale, first capture the latent, part of the ruler, and a little bit on each side of the latent so there is room to crop the image to a known size. Next, you will crop the image to a known hash-marks on the ruler, and re-size (without re-sampling) the image to the newly-cropped size. This is an easy combinations of tasks in photoshop, or whichever imaging software you are using. Naturally you will keep the proportions of the image. If you have any questions about this, either post another message here (because others probably do too) or e-mail me and I will give more detail.

-Kasey
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Duane Moriarity
Posted on Thursday, January 31, 2002 - 08:35 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

We are switching to digital imaging (from 35mm) for our crime scene and latent processing (1:1 shots). We have the sofware in place but I would appreciate some info on what printers work well in obtaining a 1:1 with sufficient detail for AFIS. Also, information on a good system of scaling the latents without having to make 50 copies to get it right would be appreciated. Any other suggestions on the transition would be appreciated as well.

Thanks

Duane Moriarity
Dormont Borough Police Dept

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