Electronic part and software of "Zenit" objective

The project was executed for S.A. Zverev factory in Krasnogorsk, aka "Zenit". Amateur photographers and professionals surely know reflex cameras from this manufacturer.

To date the factory produces objectives for cameras of many popular brands.

For the utmost use of all objective functions by the camera the objective should incorporate an electronic part which, in simple cases, will simply inform the camera on objective parameters (light intensity, focal length, etc.) and, in complex ones - will control the drives (focus, optical stabilization, etc.).

We were asked to develop an electronic part for a simple (fixed) objective and to write firmware for its microcontroller.

Within the scope of this project, we carried out the following works:

  • Study of exchange protocol;
  • Writing a test emulator to testing and setting the protocol implementation;
  • Development of electronic circuit board diagram;
  • Development of a 3D model of objective case, contacts, flex-rigid printed circuit board;
  • Development of design documentation acc. to Unified System of Design Documentation (USDD);
  • Development of specifications acc. to Unified System of Design Documentation;
  • Organization and control of printed circuit boards production;
  • Writing and debugging the final firmware version (for the chosen microcontroller).

The work began with a study of the protocol, since there was no documentation for it:

Development of software for Zenit - study of the protocol

Then we used a debug board (so-called starter kit) for debugging our own implementation of the protocol:

Then we used a debug board (so-called starter kit) for debugging our own implementation of the protocol:

Then we proceed to designing the case part. The factory provided us with space in objective, where we had to place the case, contacts, flex-rigid PCB, and its fixtures to the case.

Thus, we developed the case and its "filling". The challenge was extremely limited size of device, but our designers found implementation way that allowed us to put in all the planned parts.

3D model of developed objective case

After approval of 3D-model, we proceeded to drawing up design documentation and specifications. All design documents were drawn up with strict observance of USDD requirements.

Assembly drawing. Image on the site is intentionally made unsharp.

Assembly drawing of contact and software case

Diagram of circuit printed control board. Image is intentionally made unsharp.

Diagram of the control board for Zenit objective software

Manufactured control board:

Manufactured control board with objective software

Then we have developed the final firmware version for the chosen controller.

The last stage was testing in a real camera:

Testing the camera control software

Currently, the factory is launching a series production of elements developed by us.