The LockTight media can only be read by the proprietary LockTight card reader. The reader intefaces with the PC via FireWire. Lexar LockTight CompactFlash cards are signified by the "Lt" logo. The cards are professional-quality digital media, so they're not cheap.
As a major crimes detective, forensic photographer, and crime scene investigator, I have often been asked to provide assistance to law enforcement agencies that were transitioning to digital imaging for evidence photography. One of the most common questions that I have heard in this capacity is as you might guess, “Are digital images accepted in court?”
The simple answer is, “Yes.” I am not aware of any court case where a judge has denied admission of digital photographs into evidence based solely on the technology used to capture the images. That said, it’s important that the law enforcement community establish standard operating procedures that preserve the chain of evidence and the integrity of the captured data so that digital images will continue to be accepted in court.
A critical concern in this area is image integrity. Anybody who has ever seen Adobe Photoshop knows that digital images can be manipulated very easily by anyone with a decent computer and a minimal investment in learning the program.
So if we are going to use digital images in court, we have to find a way to prevent any image manipulation, at least until the images are transferred to archival storage and working copies are made for enhancement purposes. And we also have to have a way to prove the integrity of the images in court.
The need for law enforcement to have a tool for securing forensic images and demonstrating their veracity in court is well know among digital photography companies. And a number of these companies have tried to address the issue. The latest technology in this category is the Lexar LockTight system.
LockTight is a unique solution that provides card-level access control to help guarantee image integrity. Simply put, the LockTight system makes certain that no unauthorized users can access images stored on a LockTight-enabled CompactFlash card. If you can’t access the images, you can’t alter them.
The LockTight system consists of four components: a digital camera, a dedicated CompactFlash card, a special card reader, and the LockTight software package.
LockTight utilizes an authorization process based on the 160-bit HMAC encryption algorithm. Unless you work for the NSA or in digital file security, that probably doesn’t mean very much to you.
So, let’s simplify things a bit. The level of encryption afforded by the LockTight system is really secure, and that means that the data on a LockTight card is “locked” until the authorization process occurs between the LockTight card and either the camera or computer trying to access the card.
Let me explain that last sentence. The LockTight system isn’t an image-authentication process. Data on the card isn’t encrypted. Instead, LockTight controls access to the data stored on the card. Because the image data isn’t encrypted, it’s not changed or altered in any way.
The memory card is “unlocked” by entering an approved user name and password. This lets the user access the camera’s CompactFlash card in the LockTight reader. Once access is granted, the CompactFlash card shows up as a normal drive on the user’s computer desktop, allowing data to be transferred to archival storage per the agency’s standard operating procedures.
Currently, the Nikon D2X and D2Hs are the only digital cameras compatible with the LockTight system. (See “Cameras That Work With the LockTight System” in Sidebar below.) Lexar plans on adding additional new cameras in the future.
The Nikon D2X is an excellent camera for photographing forensic evidence.
Lexar LockTight memory cards comprise the second component of the LockTight system. The LockTight memory cards are Type I CompactFlash cards available in sizes from 512MB to 4GB. This is high-quality digital media. The LockTight CompactFlash cards are based on Lexar’s professional 80X speed cards, which are highly regarded among professional photographers.
Unfortunately, professional quality media is not cheap. Expect to pay about twice as much for LockTight cards compared with standard CompactFlash cards.
Security is part of what you are paying for. The LockTight CompactFlash cards contain proprietary software and hardware that allow the cards to be accessed only by a LockTight-enabled card reader and LockTight software. Also, LockTight memory cards can only be used in cameras that have been “keyed” to the memory card. The data stored on the cards cannot be read by non-LockTight card readers.
Once the digital image data is stored on the memory card, the special LockTight card reader must be used to access the data. The LockTight card reader features a high-speed FireWire interface to speed image transfer to the computer, which makes a real difference when you’re transferring 4GB of image data off your card into a PC.
The “lock” part of the LockTight system is Lexar’s proprietary software. The software has two parts: LockTight Admin and LockTight Access. LockTight Admin allows the system administrator to manage the LockTight memory cards, cameras, and system users. LockTight Access grants approved personnel access to selected memory cards. LockTight Admin and LockTight Access are included with the LockTight hardware.