Nikon Aculon A211 10x50 vs 12x50

[dannybgoode]

Whilst I am new to astronomy I am not new to photography and have been assessing optically quality of lenses etc for years.  With this in mind I thought I would share my thoughts on the above bins as I did not see much about them when researching astronomy forums what to buy (although there were plenty of glowing reviews on Amazon, B&H Photos etc).

As some of you know accidentally ended up with a pair of Nikon Aculon A211 10x50's and the 12x50's giving me the chance to compare both side by side

To be honest I wanted to like the 12's more - I thought the extra magnification would be useful (beginners lust for all things high-mag!) but in the end it wasn't even close, the 10's won by a country mile.

In daylight the 12's are ok but the image is a little soft and suffers from very noticeable chromatic aberration off centre (I will now refer to this as CA and it shows itself as a purple fringe or 'glow' around high contract edges - say a TV aerial against the sky or the edge of a star against the night sky). This is very off putting and detracts from the overall image quality (IQ).

Things are much worse at night. I just could not get a sharp image with them, the CA was very off-putting and the smaller exit pupil compared to the 10's meant everything was on the dark side.

Star clusters that were popping out on me with the 10's were sometimes barely discernible with the 12's and the narrower field of view meant less could be seen in any one view. To be fair as well for astronomical use the extra magnification on offer with the 12's is marginal anyway and given the limited light gathering of the 12's I would say they are somewhat behind the 10's

Pluses? Build quality is as you would expect from Nikon and the supplied carry case and neck strap are very good. The lens coatings are effective at keeping down unwanted reflections (but not the CA unfortunately).  Collimation seems good and everything is nice and tight but not overly stiff.

As for the 10's - they have all the good points of the 12's - build, decent accessories etc but they are also optically nice indeed.  Great contrast, pin sharp focussing with the desired 'snap to' when dialling the wheel, nice and bright with a good FoV (6.5^o).  i could see jupiter + at least one moon last night, M44 was mesmorising and Mars had a distinct hue to it.

Collimation seems spot on (would expect that from Nikon to be honest) and the lens coatings are effective when given a blast of a bright torch.  Exit pupil is also actually 5mm (again would expect nothing less from Nikon).

Negatives - expensive at the typical high street asking of around £120-140 but can be found on eBay for as little as £80.  Also, some CA is present on very high contract objects during the day but have not noticed any at night yet.  Also they are not waterproof.

Would I have bought them at the £120 mark - no, I would have gone for the OLY DSPI 10x50's or the Helios Naturesport + but that said, if you can find them the right side of £90 I would say one to consider if looking for a pair of 10x50's.  Quality Nikon optics and build.