Hioptic 6" Maksutov Cassegrain NMC1900x152 Telescope Review

HiOptic 152 > First Light

FIRST LIGHT

TERRESTRIAL OBJECTS

After aligning the finder scope with the OTA the first object to try was the cockerel weather vane on top of the church 1km/0.6mi away. The image below was taken though a Meade 40mm Super Plossl lens. The supplied 20mm lens was tried but it was unable to come to a sharp focus. The weather couldn't decide between sun or thunder and the seeing was difficult so this was put down to bad seeing. It is worrying however that Hioptic don't provide an eyepiece wide enough to cope with all seeing conditions as an inexperienced telescope user might assume their telescope was broken!

UPDATE: Having tested on a day with clearer conditions a full range of eyepieces from 40mm-6.4mm have been now been used. With the 6.4mm the beak of the bird filled the view in the eyepiece and was clear and sharp.

When it became dark, seeing was still poor, and clouds covered the night sky. However, about 8km/5mi in the distance, below the cloud line, the local TV mast lights could be seen and these were used for the first dark tests.


Sub 1 second exposure.	15 second exposure.

The light gathering ability was impressive for a Maksutov with a 15 second exposure looking like it was taken in day conditions. The images showed noticeable tripod wobble indicating the EQ3 would be difficult to use for even basic astro imaging. The lights in the image also showed noticeable blooming (star lashes) which is probably due to the the lack of anti-reflective corrector coatings. This however, is a question of taste, some people like pinpoint stars, but some prefer a more artistic star and even resort to Photoshop to add them! A user could always use eyepiece filters to reduce this effect if they didn't like it.

MOON

Early in the evening the moon put in a brief appearance while darting in and out of the clouds. The views through the scope were very sharp, and where the craters cast a shadow, they were very rich in detail. It didn't appear so bright that it would require a moon filter. At 40mm, it took up the whole eyepiece and the supplied 20mm was unable to put the whole moon in the eyepiece. There were no signs of of blue and red fringing around the edges using the eye. Sadly the seeing conditions were not good enough to try out the 6.5mm eyepiece.

JUPITER

Later that night Jupiter came up above the horizon and there was just enough time between the clouds to catch a glimpse.

The view was too bright in both 40mm and 32mm eyepieces. The eye could see a big white circle (Jupiter) and 4 bright dots (it's moons). Colour fringing was obvious, but maybe just the result of an over bright image, being low on the horizon and bad air conditions. Normally this reviewer would reduce the brightness by using more zoom with a closer lenses but these were unable to get focus due to the poor seeing conditions. It was clear that Jupiter on these wider lenses would benefit from a planet or moon filter. It was so bright any details were being washed out. The manufacturers specification suggested including sun and moon filters but none was supplied with this kit.

The image below was a single frame captured on a Casio QV-2900UX digital camera. Even on the camera the image was too bright so the cameras zoom and high shutter speed were used to reduce the glare.

The four moons in the image above may be hard to see if the reader is viewing in a bright room.

STARTEST

A few days later conditions cleared enough to do a star test on Capella. Capella is the 6th brightest star in the night sky and through this scope twinkled and showed signs of beginning to bloom. Other stars nearby just exhibited the pin sharp white dots you would expect from a Maksutov. With Capella centred in the eyepiece it provided near perfect collimation defocused circles so there doesn't seem to be any issues with collimation on this scope.

SUMMARY

Despite the poor conditions the views from this telescope looked very promising. It provided typical sharp Maksutov optical views on rich dark backgrounds despite the reviews light polluted sky. It does seem to have a bit of blooming on very bright objects, maybe the result of lack of corrector coatings. There also seems to be a bit of colour fringing. I'm putting this down to the objects being low on the horizon and suffering air de-fraction, for now, until the weather gets better.

Summer is never a good season for testing a scope so expect an update to this review in the winter when hopefully we can split some stars and try some DSOs (Deep Sky Objects).

SECOND LIGHT

On a slightly clearer night a better shot of a nearly full moon was taken. There was a little colour fringing with a small amount of blue at the top and red on the bottom. The moon was still low on the horizon so we can't rule out this being the result of air de-fraction yet.

THIRD LIGHT

A few days later the moon was higher in the sky and no signs of colour fringing were noticed in either the eyepieces or camera image so we can definitely put this effect down to low atmosphere conditions and not the scopes optics.