Zoom eyepiece 8mm shootout

[bomberbaz]

Well I might be overstating what actually occurred by calling it a shootout but I did go out with good intentions. Before I write further I will just throw out a couple of caveats:

1 I have had only very limited time behind an eyepiece this last 12 months due to personal reasons so I am very much out of practice.

2. I make no claims to be an expert in these matters although I have a few years experience.

Ok on arrival at my designated dark spot I arrived to a bog on the land where I park my car, that is the only place and I had no other option but to park there. 🙄 Ok so I parked there, then started to get into my fur lined boots whilst trying to not stand in 3 inches of mud, 1 of my thick socks fell into the goo which I managed to recover before it got soaked, the signs were ominous.

My recently bought setup head light broke, it is supposed to be bright red single led which is far to bright for observing but good enough to put your gear out whilst allowing your eyes to settle. Well it decided red was out and decided it only wanted to shine in white, 2 very bright white led's. Then whilst putting my dob base down in now white light the zip on my coat went (lockdown pounds still remain I am afraid) and by now I was feeling a little windless in my sails!

Then my DSC would not connect, after 20 minutes I found out that my new phone fills in the skysafari IP address with a default and more importantly, wrong one so it wouldn't connect to the scope dsc. Honestly had i not already set up I would have packed up.

Anyway, I got this far so here goes. Eyepieces tested were the 7.7-15.4 APM superzoom / Baader Mklll 8-24 / sVbony 7-21 / sVbony 3-8 and as per title all were only tested at 8mm (initially). The instrument was my Taurus 14" dob. No false colour from the optics here. I also viewed everything without my specs as the exit pupil allows me to ignore my astigmatism.

So to results, this is the boring bit 😂 I had prepared a list of objects to look at but being honest, I couldn't be bothered with my methodical list I had put together so simply did a few objects of differing types.

Saturn.  APM won here on the grounds that with direct vision Dione was most readily available, it just popped into view so easily where with the other three it was there but popping in and out, but not quite as easy. For contrast and sharpness on this all 4 performed well although the baader was ever so slightly softer but not significantly. It really was a close call and on another night you might call them the same. 

M15, Pegasus cluster. Nothing in them really as far as I could tell but I enjoyed the test. There is something about a globular at x200+ in a good aperture that moves you.  Even with direct vision individual stars were resoled with each eyepiece, with a slight averted they were popping out for fun.

Almach double next. Again all four showed excellent colour correction, earlier collimation on setup paid great dividends here as the stars were very tight and I couldn't really split out a winner as such.

M57. All four offered hints of colour, image of the nebula itself all presented a well defined shape with each eyepiece with nothing jumping out with higher definition.

I saw no internal reflections or signs of false colour. I didn't test edge of field correctness but nothing jumped out and shouted mehhh! 

I decided to have a go M81 / bodes, I had already earmarked this as a shootout just between the APm SZ and the sVbony 7-21. I could have added the baader but I had heard such good things of the sVbony I decided to keep it simple.  It was at this point that the quality and build of the APM SZ shone through. After settling on M81, the SZ smoothed from 14mm to 8mm with reassuring ease with little clicks to tell you where you were on the magnification scale. The 68 AFOV thoughout the range was a real plus whilst enjoying the travel and it simply felt so comfortable to use whilst dialing up and down the range.

The sVbony 7-21 had no clicks to tell you where you were, the zoom from 21mm/40 AFOV though to the 7mm/60 afov didn't feel anything like as smooth as you peered into the eyepiece. As you dialled up and down the range it almost felt like a film special effect in comparison and at this point I noticed a very big difference to me. The field stop on the 7-21 was almost fuzzy compared to the sharpness of the SZ. I checked several times and found the SZ to be clearly defined but the 7-21 was a poor second.

I continued viewing doing a little doubles marathon with the APM SZ staying put in the scope and the others relegated back to the EP case until 8.30 when cloud bubbled up. I packed up here cos my feet although dry were cold as a result of the environment in which I found myself. 

Now if I was given the option of owning only one eyepiece out of the four, I would probably say the sVbony 7-21 would cover most bases and would get my vote. If you want to know which one I find the best, it is without a doubt the APM SZ although it's two negative are the shorter range covered and the fact it really is a 2" eyepiece for most people. It won't reach focus at 1.25 but the eyepiece body is 2". Don't let that put you off if you want a fantastic zoom that simply oozes quality. It is the first time it has had real use by me since I bought it and I am very happy with what it is yielding.

 

 

 

Edited November 11, 2023 by bomberbaz

[John]

Great report Steve 🙂

Since you kindly loaned me the APM and Svbony 3-8 zoom I have acquired my own 3-8 which I am really enjoying.

 

 

[bomberbaz]

18 minutes ago, John said:

Great report Steve 🙂

Since you kindly loaned me the APM and Svbony 3-8 zoom I have acquired my own 3-8 which I am really enjoying.

 

 

Yes it is a nice piece of glass John, some people have complained about the short eye relief but personally I find I get on with it very well (from limited use). I think that it will find more use in my 100ED than the dob but it's a great bit of kit for the cost. 

Edited November 10, 2023 by bomberbaz

[Space Hopper]

I have the APM SZ as well, and its always impressed me. 

Best zoom i've used so far.