Anton Roland de Klerk (Antonroland)
Post Number: 2
|Posted on Friday, September 07, 2007 - 02:04 am: ||
Guys and girls - anybody out there?
The Nikon and Fuji S X Pro seem to be the popular choices out there.
Anyone use Canon?
Anton Roland de Klerk (Antonroland)
Post Number: 1
|Posted on Thursday, September 06, 2007 - 07:14 am: ||
A huge lot has happened in terms of new technology. What is being used lately (in terms of camera/lens combinations)?
Andrew Reitnauer (Unregistered Guest)
Posted From: 18.104.22.168
|Posted on Wednesday, November 01, 2006 - 09:39 am: ||
My Unit is completely digital. I have had great success in caputring ALS photos with Ardrox at 415nm and a yellow filter, or recently great photos at 415nm, no filter but setting the camera to capture B&W images only. Here we use a Fuji S3Pro, great camera. Both of the methods above will also capture a normal scale.
|Posted on Friday, August 30, 2002 - 08:51 pm: ||
Our office just received 2 Nikon D-100 which utilizes the 62 mm lens and is a SLR with a CCD. It will produce a 1:1 image in 35 mm format. Give this a look. They seem to work great.
|Posted on Thursday, April 18, 2002 - 02:11 pm: ||
The most important issues when discussing digital photography related to examination quality capture are the 1) distance of the image from the lens, 2) quality / specs of the lens and 3) resolution of the capture device.
If you have a great lens and you can get close to the print BUT you have a $40 Wal-Mart special, it won't capture the resolution necessary for a detailed examination. Similarly, if you have a top of the line digital camera and lens but you are trying to capture a large area (full palm print), then the resolution of any small area within that image may not be great enough for examination purposes. A combination of a good quality lens, camera body, and knowledge of resolution versus print-to-lens distance WILL permit examination quality images in today's digital environment. (output aside)
At the Mississippi Crime Laboratory, we have "gone digital." We routinely take digital photographs of latent prints for comparison purposes and archival purposes. Each laboratory is equipped with a scanner, and a Kodak DCS300 series digital camera with a 60mm lens for this purpose. This close-up lens allows an average latent fingerprint to fill the view box of the camera, providing more than enough resolution for comparison. Just the other day I captured a print in this manner that, when re-sized (without re-sampling) according to the scale in the photograph, resulted in an image resolution of over 2300 dpi.
I just ran a few tests (while in the middle of this post!) to help demonstrate the correlation between image quality and distance of the image to this lens using this camera. Keep in mind that this is a 3 mega-pixel model (1504 X 2008) with a 3:4 aspect ratio. Each TIFF image is 3.3 MB. Using the 60MM lens, a view of approximately 2 X 1.5 CM (filling the screen) resulted in an image quality of 2862 ppi. Yes, over 2800 dpi output could be supported. Obviously, even a latent print containing very little level 2 detail but having a high degree of clarity could be captured and compared on-screen by getting as close to the print as possible (with this camera and this lens). And we do this on a routine basis.
Backing the camera off to include a wider (and more practical) field of view, the resolution decreases to just over 1000 ppi by the time we include 5X3+ CM in the viewfinder. Obviously this is only about 25% of the entire area of a full palm print, but this is still an examination quality print. If I were documenting a latent print larger than this, I would think it sufficient to take an over-all photograph showing the location of the print on the surface combined with another examination quality photograph taken close-up of the clearest area of ridge detail. Naturally, most of the latent prints we deal with on a routine basis do not fill a 5X3+ cm area.
Again, it is important to remember that these resolution experiments apply to the Kodak DCS 300 with a 60MM lens. If the camera you are considering purchasing is less than a 3 mega-pixel camera, then you will not be able to capture a 5 X 3+ CM area at 1000 ppi. The resolution would be proportionally less than this. Also, if you do not have a close-up lens, you will not be able to get as close to the print, and you will be forced to take photographs containing wasted space around your print resulting in unnecessary wasted resolution.
It all comes back to filling the frame with your image to get the maximum quality capture.
I hope this helps. If you have any questions, please feel free to contact me or post again.
|Posted on Thursday, April 18, 2002 - 11:49 am: ||
For ALS photos, I am trying to explain to my boss that the digital 35mm format (Nikon camera with Kodak back) is not sufficient to capture fingerprints or palm prints while also including a scale and identifying information. The format is just to small to capture 1:1.
We are currently photographing ALS work with 4x5 sheet film and then scanning the negative with a flatbed scanner. We print originals and reversals adjusting contrast and brightness to the examiner's wishes in the digital darkroom.
Can anyone inform me otherwise or give me any further information?