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Focusing Rail for Focus Stacking in Magnifications up to 5:1

The CASTEL-M focusing rail is the latest in innovative technology from NOVOFLEX. Its stylish and unique design is aimed at photographers who frequently work at magnifications from 1:1 (life-size) to 5:1. The manual focusing rail is exceptional in its construction and specifically manufactured for the application of focus stacking in a series of progressive magnifications to a maximum of 5:1. The CASTEL-M bridges the gap between high-end electronic rails such as CASTEL MICRO and conventional rail design. 

Depth of field is one of the most challenging aspects of macro photography to overcome. As magnification increases, the depth of field decreases, especially above 1:1. The diminishing depth of field at reproduction ratios above 1:1 requires extremely accurate and precise camera advancement to create identical distances between the individual images of a typical stacking sequence. Precise overlapping of each image is necessary for the stacking software to create a successful composite photograph. The CASTEL-M works with a wide range of specialist lenses such as Canon MP-E 65mm f/2.8 1-5x Macro Photo and the LAOWA 25mm f/2.8 2.5-5x Ultra Macro which are frequently used by macro photographers who routinely employ focus stacking in their workflow. It has been specifically designed to assist macro photographers in achieving consistent, predictable results when engaged in this repetitive task and throughout a range of different magnifications.  

At the heart of the CASTEL-M is a spindle that drives the sliding camera mount forward with extreme accuracy for each image. It also has practical indexing steps for magnification factors of 2:1; 3:1; 4:1, and 5:1, which are selected via a lever located on the inside of the focus wheel cylinder. Releasing the locking lever on the sliding block disengages it from the spindle and allows the base to be positioned freehand at the starting focus point. Once in place, it can be re-engaged securely with the spindle by locking the lever. Progression through the sequence of images is carried out via a single click of the focus wheel, which advances the camera assembly clockwise in precise incremental stops to the focus point of the next image. No need to worry about calculating the step size and precise overlapping of the individual pictures; the rail does this for you automatically. The click stops have been calculated in such a way as to avoid the negative effects of lens diffraction. They have been calibrated for 35mm Full-Frame cameras with attached lenses at an aperture setting of f/4. Cameras with smaller sensor sizes, such as APS-C, etc., can be used reliably up to 4:1 and Four-Thirds sensors up to 3:1. When complete control of the camera advancement is required by the photographer, measured repeatable step-sizes can be achieved with the help of the laser-engraved scaling on the focus wheel. When necessary, the sliding camera mount can be advanced arbitrarily without engaging click stops. A complete rotation of the focus wheel equates to the movement of the sliding block and camera assembly by 0.8 millimeters. The scaling enables repeatable steps of 0.01mm feed to be achieved.  

For use in product photography, the CASTEL-M can be equipped with the CASTBAL-PRO bellows attachment, transforming it into a fully-fledged technical camera. In this configuration, the stacking steps are performed by moving the bellows rear standard, while the lens standard remains fixed. Utilizing this approach means the position of the lens does not change in relation to the subject, which may be important in controlling unwanted reflections, especially in jewelry and other similar types of photography. In commercial product photography, objects with a depth greater than 100mm can also be stacked in this way without difficulty, since only the focus is adjusted, in contrast to the usual stacking methods where the entire distance must not be covered. The advantage of this stacking technique in comparison to the classic tilt adjustment according to Scheimpflug is understandable. With focus stacking, uniform, and maximum sharpness can be achieved over the entire subject area (from front to back and simultaneously from top to bottom), in contrast to the Scheimpflug method, where maximum sharpness can only ever be achieved in a single plane irrespective of adjustment. 

The  CASTEL-M is, of course, completely integrated into the ARCA-compatible NOVOFLEX Q system on the top and bottom, which means the CASTEL-M accommodates compatible interchangeable plates and NOVOFLEX bellows. It also is compatible with other NOVOFLEX focusing rails for setting up a cross-rail system, which can be repositioned by 90° and at the same time can be directly inserted and clamped in matching coupling mounts.  

Technical Specifications:

Length: 20,5cm/8.07“
Width: 6,5cm/2.6“ at moveable camera mount, 5cm/1.9“ at the rail, 5,5cm/2.2“ at the Focus wheel
Height: 5,5cm/2.2“ at the Focus Wheel, 4,5cm/1.8” rail with moveable camera mount
Weight: 679g/1.5 lbs.
Max travel: moveable camera mount: 100mm
Revolution: One full revolution of the Focus Wheel equates to 0.8mm of travel
Scaling: Laser engraved scaling with 0.01mm division
Max. Payload in vertical position: 4kg/8.8 lbs
Quick release unit: ARCA-compatible, can be turned in 90° angles, Spirit level, Safety-Pin for NOVOFLEX-coupling plates
Rail: at the bottom ARCA-compatible over the entire length of the rail, 1/4"-20 and 3/8”-16 sockets

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