VARIOCHROMAT Digital Enlarger

The VARIOCHROMAT is a new design of digital exposurer for both small and medium sized professional photo labs, with the ability to expose onto any photographic material, e.g. black and white and colour.

A development by the German professional lab Polycolor owned by Kai Sandner, the VARIOCHROMAT is utilised in the company’s daily business, enabling black and white prints to be produced from digital files.

Kai Sandner

The core part of the VARIOCHROMAT is a monochrome 7" CRT (cathode ray tube) which has the highest resolution in the world. The spot size (diameter of the electronic beam) is only 18 my (mycron) and enables 6400 x 4800 dots to be displayed onto the CRT screen. As a result of this, the VARIOCHROMAT shows 30.7 million pixels. The CRT, together with the main electronic unit, is located in the head of an enlarger, so adjusting the picture size is done in a similar way to that of a conventional enlarger.

The software runs under Windows XP and is responsible for the correct display of the tonal and colour values. For each type of photographic material a profile has to be set up and a grayscale is produced and measured with a densitometer. Based on this, the software renders correction values to optimize the picture quality.

Colour prints are produced in the following three steps (RGB, red, green and blue) with a 24 Bit depth. Black and white prints are exposed in 10 Bit (1024) grayscales.

The VARIOCHROMAT can be operated with every modern PC with a colour adjustable monitor. A special interface card for the data transfer is provided which requires a PCI slot.

All photographic materials (sheet film and papers, also black and white) up to 23" x 35" can be exposed. For larger formats, inter-negatives can be produced. These can also be used in horizontal enlargers. The use of a roller easel (roll cassette) for the automatic production of large quantities is also possible.