Fast optics in imaging, the exposure times are considerably shortened compared to the instruments featuring a F/8 focal ratio or more. In addition, with its image circle of 100mm diameter, the BRC-250 authorizes the use of films or sensors of average format for the astrophotography of faint objects. The field of 4,5° is then exceptional for such a diameter. The objects of great angular size will appear with a resolution seldom reached by an amateur telescope. No doubt also that imagery CCD lovers will find a reflector to exploit their sensors, no matter the size.

Such a level of optical quality would be completely useless without a suitable mecanical engineering. Takahashi thus integrates and uses the best machine elements tested on its Mewlon and Epsilon series of large diameter
The primary mirror cell, fully adjustable, avoids the optical risks of stresses whatever the orientations of the optical tube towards the sky are. The collimation of the primary mirror is adjusted by 3 groups made of 3 screws (2 pushing screws and 1 drawing screw) and will ensure the necessary precision to this delicate operation.

The purists will find an oversized capstan focuser to receive the heaviest instrumentations without forcing nor to weaken the focuser. It integrates a built-in camera angle adjuster ensuring framing of the film or camera CCD without loss of focus. This capstan matches perfectly the BRC-250 and is fully justified considering the weak focusing tolerance of the very fast telescopes. During focusing, the material moves with rotation, while a brake maintains the focus point.

The spider with 4 vanes and the support of secondary mirror are completely adjustable. One finds there the precision of action which will be necessary during collimation.
The installation of the optical tube on mounting is ensured by 2 cradles linked together on their upper part by a rigid plate, the whole firmly mounted on the traditional plate TMP0210. The BRC-250 can be mounted on JP-Z and EM-500 mounts by using this same plate.