The LensAlign Focus Calibration System (Pro Version) is a unique and accurate way to check the focusing performance of your camera and lens combinations. This system provides you with a reliable and easy way to make sure your expensive photographic equipment performs at optimum level. After all, you want your images spot-on sharp since anyone in the business knows that clients don't like excuses - and when you only get one chance to get that money shot, your gear must be in peak condition.
However, no matter what camera/lens you buy, it's probably been mass produced. Even though manufacturers allow for production tolerances, mistakes happen and it is rare that perfection is achieved. If, by chance, your camera is "off" by a fraction and you couple that with a lens that is also off just "so-much", the combination produces an image that will be soft.
Further complicating the equation is what happens when you take it in for repair and the service center decides to over-compensate for the amount that is "off" and instead of dealing with a lens that used to front focus, you now have a lens that either front focuses more or that now back focuses.
LensAlign is a hardware-based tool that permits you to "pair" a camera/lens combo for maximum sharpness. By measuring whatever deviation this combo produces, correction can be readily achieved using the built-in adjustment for auto focus that many of today's high-end cameras possess.
The system is easy to use. Tripod mount your camera while placing the LensAlign on a table or additional tripod and focus on the center focus spot of the target (adjust position of camera to center the target). When this is achieved, both the imaging plane and target will be parallel. Set the DOF scale, adjust it as per included instructions and make an image (or images) of the setup. Once you capture the image, minor adjustments can be achieved using the focusing micro-adjustment control on your DSLR. It's that easy.