Review of Visionary Classic 7x50 Bins

[Chris]

I've been wanting some 7x50 binoculars for a while now as I have quite large pupils that would make use of the 7mm exit pupil they would provide (50/7=7.14). My logic was that all things being equal such a large exit pupil should give a comparatively bright image for Astronomy purposes:)

As is too often the case my budget was on the low side (20-30 quid) so I did the usual Googling to see whats about when I came across Visionary which is a brand I've not heard much about in Astronomy circles. Visionary Classics were the budget models in the range which have basic optical coatings and BK7 porro prisms. The best price I could find on these was 19 pounds with free delivery which is well, worryingly cheap! However, this reminded me that the Celestron UpClose where around the same price and many people find those perfectly ok so I thought I'd give them a go despite concerns, if nothing else I would gain some knowledge about the budget end of the brand which would enable me to write this review:)

They arrived well packaged in two layers of boxes plus bubble wrap and a soft case for storage, a microfibre cloth was included but a strap wasn't. When I took the objective lens caps off I noticed that one was very tight and the other was much looser which gave me an idea of the kind of tolerances used during manufacture. The binoculars themselves felt fairly light and because they are fully rubberised they were good to grip and felt comfortable to hold. When I took them out during daylight to test them I quickly noticed a double image, It was only when I looked at the bins a little more closely that I noticed the left barrel was screwed into the prism housing at a distinct angle. As the packaging was pristine I can only imagine that this was a manufacturing error rather than a knock during transit which again reminded me of the ill fitting lens caps or indeed dodgy diameter objective barrels? I decided to see if the barrel would gently unscrew so I could attempt to correct this misallignment and fortunately it did. I noticed that the plastic thread was cross threaded to some degree so whoever screwed it on to begin with clearly needs some further training:D Anyway, I managed to refit the barrel much more flush this time and when I looked through them again the image looked much better with no ghost images, happy days:)

A couple of nights later the seeing was excellant so after setting up my scope and camera to image M57 I eagerly slumped down in my camping chair to have a good look through my new bins. I focused on Vega so I could check the optical quality, moving the bright star around the field of view quickly showed that something wasn't right. I know that unless you pay a lot of money your going to get some degree of field curvature and wonky stars close to the edge of the FOV but this was in a different league, also the distortion wasn't isocentric if I moved Vega slowly from the centre of the FOV to the upper right quadrant the image degraded very quickly starting at about a 3rd of the way out with Vega sprouting a diffraction spike at the 3 o'clock position, then as I moved it further out it quickly transformed into a blurry line type thing by the time a got it close to the edge, this also happened in the other directions but to a lesser extent, it really was the upper right portion of the FOV which was to be avoided if possible. I then decided to check both lenses by closing one eye then the other, this revealed that on the left side of the binocular the upper right portion of the FOV was badly effected as mentioned, and on the right side of the binocular the upper left portion of the FOV was badly effected.

Putting the optics to one side I noticed that focus was very difficult to maintain, if you rested your eyes on the eye cups it would actually turn the central focuser a little bit, not only this but there was a lot of flexure in the thin plastic bar that attached the eyepieces to the focuser. I guess this would be less of a problem for daytime viewing as this may consist of more horizontal viewing where you're not resting the binoculars on your eyes as much as vertical viewing, but for Astronomy it made things pretty tricky. Whilst the focus was quite loose I found the Dioptre very stiff, I think this would have been better the other way around.

In Summary, I think for daytime use these binoculars are ok for someone on a very tight budget, as after the initial fixing of the barrel alligment I thought the daytime views were fine. Unfortunately the large contrast between the black sky and bright stars really showed up the optical flaws of these binoculars, this coupled with the poor quality focussing mechanism means that in my opinion these particular model of binocular should be avoided for Astronomical use, but hay what did I expect for 19 pounds:)

p.s. I have emailed the supplier to see if I can return them for a refund, if so I can put the money towards some better quality binoculars I'll be saving for, lesson learnt:)

Chris