Orion Optics UK OMC 140 Standard 140mm F14 Maksutov OTA

Why is the OMC140 so special? and why has it built up a reputation over the last decade or so? . . . quite simply it is a quality instrument as far as optics are considered but, it is also mechanically excellent and stable and . . . Development, development and development, all done in conjunction with experienced amateurs and professional astronomers and two very experienced optics designers, Barry Pemberton and Harrie Rutten.

The OMC140 came into being as a challenge in achieving a wide field, photo visual Maksutov Cassegrain with incredible stability and versatility.
The project was a success and we judge that by considering the large number of these compact instruments we have in use in every continent of the World.

Why is it so successful? The design is not a standard all spherical one with a main mirror the same size as the corrector. That is the traditional Maksutov design but, it lacks off axis performance and suffers from coma. The OMC140 has an ellipsoidal primary which is over 12mm larger in diameter than the Maksutov corrector. This added aspherisation of the primary allows much wider flatter fields to be achieved but it virtually eliminates coma.

The spot diagrams for the OMC140 are nothing less than spectacular and this illustrates a 30mm field.

The carbon tube of the OMC140 allows almost perfect stability of focal length and strength. The unique cantilever focusing method ensures image shift/mirror flop are things of the past. We guarantee the OMC140 will give less image shift than a just a few seconds of arc, it's that good, really. Focusing is carried out by means of a spring loaded micrometer thimble, coupled to the internal mechanism to give the most precise and the smoothest focusing action you could think of. People often say their focuser is "as smooth as silk", this one really is, it's like butter smooth.

What do you get in your image quality? The best image possible for the aperture. The OMC140, because of its relative compactness regularly gets compared with larger Maksutovs and refractors, some costing over 8 times the cost of the OMC-140. We have not come across any refractor of the same aperture which outperforms it, if you know of one, please let us know.

The OMC140 is offered in two optical grades, the standard model and the De-Luxe model with Lambda/ 6 optics.

What do other people think about the OMC140, well, we were asked to enter it in a Sky at Night Maksutov competition a few years ago where it competed with some scopes costing significantly more and, one larger in aperture. We'll leave the closing comment of the review to answer that question…

"the OMC140 deserved first prize for its high-quality views not just of planets but also of deep-sky objects. In the end it was those memorable moments with the Orion Nebula and Saturn with this telescope that swung our view in its favour"

SKY AT NIGHT MAGAZINE