developing latents on carbon paper

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Ian Fleming
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Joined: Mon Jan 03, 2011 5:37 pm
Location: Tasmania - Australia

developing latents on carbon paper

Post by Ian Fleming »

Can anyone suggest the best way to develop and record fingerprints on non-carbon side of carbon paper - esp removing background which may fluoresce or interfere with prints - superglue fuming + fluorescent staining and could you try gelatin lifts or photoshop??
Graham F
Posts: 66
Joined: Mon Mar 27, 2006 8:53 am

Re: developing latents on carbon paper

Post by Graham F »

Consider; 35SO2, VMD, RTX, Iodine.
LauraT
Posts: 19
Joined: Wed Jul 22, 2009 7:26 am

Re: developing latents on carbon paper

Post by LauraT »

Hi Ian,

We are actually in the middle of a research project on developing latent prints on carbon paper at my lab. We have tested a large number of processes so far including dye stains, powders, and VMD.

Your best choice of processing method depends somewhat on the type of non-porous side you have for your carbon paper. We found three different surfaces: paper (fully porous); a slick, shiny film; and a less slick, shiny surface. Based on your questions, I am assuming that your non-porous side is one of the slicker, non-paper types. So far we have found that superglue with dye stains work well on both the carbon and non-carbon sides (even the "paper" non-porous sides). If you are having issues with background fluorescence, we found that superglue followed by silver/grey powder also works well on the non-porous side of the less slick, shiny surface - type.

All of our recording has been done with digital imaging. Even without any enhancements, we have gotten very good results.

Best of luck.
Bill Schade
Posts: 243
Joined: Mon Jul 11, 2005 1:46 pm
Location: Clearwater, Florida

Re: developing latents on carbon paper

Post by Bill Schade »

Am I the only one here scratching his head saying "Carbon Paper?"

Do they still make that stuff?

I'm sure this is a serious thread but I'm wondering what is the context in which you are
receiving carbon paper for processing? I thought of credit card receipts but have not seen carbon copies in years

And to discuss 3 different types of carbon paper. I'd be hard pressed to name three brands of carbon paper.
briano
Posts: 49
Joined: Fri May 23, 2008 7:11 am

Re: developing latents on carbon paper

Post by briano »

Carbon paper? I thought the same thing. I was able to purchase some at Office Deport the other day. 25 sheets fro $3.99. They had two typewriter models for sale too. I am contucting some test with VMD right now. Hope to be done by next week. I am also working an old case with lots and lots of typewriter paper, the very thin stuff. I hadn't seen that in years too.
Red
Posts: 22
Joined: Tue Jul 25, 2006 8:04 am
Location: Allen, Texas

Re: developing latents on carbon paper

Post by Red »

We have received kilos in our lab on several occasions that are wrapped with carbon paper. Not sure why this particular paper is used, but haven't gotten good results lately. I have used the cyano, dye stain methods; however, I have yet to try the silver/grey powder. That'll be next on the list!
LauraT
Posts: 19
Joined: Wed Jul 22, 2009 7:26 am

Re: developing latents on carbon paper

Post by LauraT »

My understanding, from DEA agents, is that drug runners think that the carbon paper defeats x-ray systems. This is probably also why they sometimes use aluminum foil.

Several brands of carbon paper can be purchased online.
Bill Schade
Posts: 243
Joined: Mon Jul 11, 2005 1:46 pm
Location: Clearwater, Florida

Re: developing latents on carbon paper

Post by Bill Schade »

Thank you Laura

Never thought about x-rays.
Tazman
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Joined: Fri Apr 23, 2010 7:25 am

Re: developing latents on carbon paper

Post by Tazman »

LauraT wrote:. . .drug runners think that the carbon paper defeats x-ray systems. This is probably also why they sometimes use aluminum foil.
Clever insects, those drug runners. I guess they fooled us, all right. Taught us a lesson, didn't they?
"Man was born free, but he is everywhere in chains." -- Jean-Jacques Rousseau
Graham F
Posts: 66
Joined: Mon Mar 27, 2006 8:53 am

Re: developing latents on carbon paper

Post by Graham F »

Yes, LauraT is correct. Carbon paper was extensively used as an outer wrapping for drugs imported during the 70’s - 90’s in the UK. Especially so for H emanating for Afghanistan. Processing was always an issue as it often got wet prior to seizure and partially disintegrated leaving everything blue.
Red
Posts: 22
Joined: Tue Jul 25, 2006 8:04 am
Location: Allen, Texas

Re: developing latents on carbon paper

Post by Red »

Much appreciated for the background information on carbon paper and x-rays. I will certainly post if I come up with a development process that works for us.
Steve Everist
Site Admin
Posts: 551
Joined: Sun Jul 03, 2005 4:27 pm
Location: Bellevue, WA

Re: developing latents on carbon paper

Post by Steve Everist »

It looks like Laura Tierney is going to be doing a lecture on this at the IAI Conference in Milwaukee (page 63 in the brochure):
http://www.theiai.org/conference/2011/2011brochure.pdf
Steve E.
LauraT
Posts: 19
Joined: Wed Jul 22, 2009 7:26 am

Re: developing latents on carbon paper

Post by LauraT »

Thanks for the plug, Steve.

Yes, I will be presenting on the results of our research project.
Steve Everist
Site Admin
Posts: 551
Joined: Sun Jul 03, 2005 4:27 pm
Location: Bellevue, WA

Re: developing latents on carbon paper

Post by Steve Everist »

LauraT wrote:Thanks for the plug, Steve.

Yes, I will be presenting on the results of our research project.
Didn't even catch the previous posts as being yours. Unfortunately I won't be there this year to catch it.
Steve E.
SConner
Posts: 145
Joined: Wed Mar 04, 2009 11:06 am

Re: developing latents on carbon paper

Post by SConner »

LauraT wrote:My understanding, from DEA agents, is that drug runners think that the carbon paper defeats x-ray systems. This is probably also why they sometimes use aluminum foil.

Several brands of carbon paper can be purchased online.
Because nothing says open me up or tear into me more than a big black void or whatever the image appears to be when you block the x-rays :roll: .
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