Focal Length: 760mm; f/5
Eyepieces: 25mm, 15mm, 10mm, 2x Barlow; 1.25-inch fit
Finderscope: 8×50 with LED reticule
Mount: Messier MON
Supplier: Telescope House
Telephone: 01342 837098
The Bresser Messier R152S refractor sits on a Messier MON2 equatorial mount and a sturdy tripod with rigid tubular steel legs.
There are three eyepieces, a 25mm, 15mm and 10mm, giving a good magnification range of 30x, 50x and 76x, which can be doubled with the 2x Barlow lens.
A 1.25-inch fit star diagonal and an 8×50 straight-through finderscope with an illuminated LED reticule complete the system.
The mount is sturdy and very smooth to move around, with hardly any play in either axis.
The mount and tripod are quite rigid and, when accidentally knocked, any vibrations quickly died down.
A polarscope with an illuminated reticule is also included, which is impressive considering this system’s price.
We found that even in the cold, the chunky locking knobs provided a good grip and were easy to locate in the dark, so moving the scope from target to target was simple.
We also liked the tube cradle.
This single unit grasped the tube firmly and made it easy to rotate the tube to get the eyepiece and star diagonal into a comfortable position.
The focuser is a large tube affair that can accept 1.25- and 2-inch eyepieces.
There’s a good range of travel but we noticed a slight shift when it was fully extended.
However, we never reached this extreme focus limit in our tests.
We targeted the star Procyon with the supplied 25mm eyepiece for our field of view test.
The star was sharp across 80 per cent of the 1.5°-wide view before distortion and slight colour fringing crept in, which was impressive.
Using higher magnification on bright stars, some colour fringing was to be expected, especially when we came to splitting double stars for our resolution test.
The double star 38 Gemini, with a separation of 7 arcseconds, was cleanly split with the 10mm eyepiece, while Castor (with just a 4-arcsecond gap) was also split at higher magnifications.
Mars was almost at its best for 2010 with a 14-arcsecond-wide disc when we turned the Bresser to it.
The planet was a small, bright orb with the 25mm, but the 10mm eyepiece showed subtle markings and a polar cap, which the slight fringing did not detract from.
With higher power eyepieces, we wrung out nice detail in the Moon’s craters.
Deep-sky targets are certainly the Bresser’s forte: the wide field of view made it possible to fit all of the Pleiades Cluster in the 25mm eyepiece’s field, while the Merope Nebula shimmered faintly with averted vision.
Large deep-sky objects such as the Andromeda Galaxy also benefited from the short focal length, wide-field views, and the galaxies M81 and M82 were pleasing to view with the 25mm and 15mm eyepieces.
Large deep-sky targets we looked at showed up well, especially the Orion Nebula, while small deep-sky objects benefited from more magnification, wide-field sights being this scope’s forte.
Overall, the Bresser comes with a lot of extras, notably the illuminated finderscope and polarscope, and its optical quality is rather good.