Those photographers who enjoy macro or close focus photography will appreciate how important a sturdy tripod and well-made focus rail are. I have always held a particular fascination for macro work as I enjoy making images that illustrate the infinite patterns found in flowers, or alien like insect detail.
For my close up work, I have used a Novoflex Castel-Cross rack for many years now. Novoflex products are exceptionally well engineered and designed to take the rigours of outdoor as well as indoor shoots. The Castel –Cross is a professional solution that, in essence, consists of two focus rails fixed together allowing fine movement in both X and Y axis. Travel in both axis is generous (X: 280mm, Y: 125mm) and when both are set at maximum the device remains stable, although a certain amount of this can be attributed to the tripod/head used.
The adjustment knobs, particularly those controlling resistance, can be a bit fiddly to operate as they are small and can get obscured by the equipment they are supporting. A little bit of trial and error adjusting the resistance goes a long way to providing very smooth travel, so it is worth investing a little bit of time getting this right when setting up. Once set correctly, there is little need to return to them.
I have used focus rails in the past that suffered from backlash, which is a real problem when working with high magnifications. A way around this was to compensate with the lens’ focus helicoid but this means a small change in magnification. It is not really a problem with lower magnifications, but in the realm of 5 or 10 times life size, it can get problematic. The Castel-Cross does not suffer from this due to the precision engineering of the screws along which the rails travel, thus allowing really precise focusing.
There is no denying that the device is heavy as it is machined from solid metal. Therefore careful consideration should be given to the underlying tripod and head as it needs to be up to the task of supporting this, the camera, a lens with extension tubes, and possibly a flash system. A flimsy tripod will only undermine the solid qualities of the rail. I have no trouble mounting it on a Slik tripod with AF2100 pistol head.
Overall, it is a piece of equipment that is a complete joy to use and it is built to take a life time of use. Highly recommended if you take your macro work seriously.