New Toy (LZOS-APM 105/650), First Light, Instant Gratification.

[Captain Scarlet]

New Toy

Ever since briefly looking through @Stu’s Tak at a WAG meet early this year, I’ve hankered after a high-quality refractor. I already own a SW Mak 127 for UK use, and it’s fine, but my memory of the sweetness of the view through that Tak was something else.

So when @Alma 's APM-LZOS 105/650 came up here, not far from where I live, my defences were already weak. I went to see it over the weekend, and quickly succumbed.

It’s something over 6kg before diagonal or eyepieces, and I don’t really have a suitable mount for it yet (my AZ EQ6 lives in Ireland). But I do have SW’s Supatrak mount, nominally rated 3-4kg, so I thought why not at least give it a go. What’s more, day 1 after acquisition turned out to be a lovely clear night, topping out at nearly 19.0 by my SQM-L in a 19.05-rated location.

The Supatrak mount, powered with the LiFePo battery pack, was fine, no problems at all. All a little springy perhaps, but it’s a super-cheap mount.

A clear night the very day after I get a new toy? I was deeply suspicious: high quality kit is supposed to guarantee bad weather for weeks.

I set it up during the bright Sunday afternoon, and pointed it at the only thing I could see from my garden more than 100m away, and what I suspect is a very popular target amongst users of new scopes: twigs in a tree. The sharpness of the view and total lack of CA at my highest magnification (108x with Delos 6mm) turned twigs and buds into deeply fascinating objects.

Finally I performed a dummy alignment to check the mount could handle the slewing, using Polaris-ish and Betelgeuse-ish, and left it all outside to get dark.

First Light

Around 1930 it was just about dark enough for my impatience. I returned to the scope and did an actual alignment. Polaris B was immediately evident even at just 36x (Delite 18.2). I had no particular plan, but I first decided to try to split Rigel before it disappeared behind the Magnolia. I’ve only done it once in a good few attempts through my Mak 127. And there it was, momentarily obvious even though there was some twinkling.

Next up was M42, and though nebulosity was evident, I have seen it much better in my Mak. It was early evening though, M42 only 25 degrees up and towards Walton and Weybridge. The Trapezium stars were sweet and beautiful, but the area was still too small in my view even with the Delos 6mm (108x) – I need more magnification.

I moved on to Alnitak, at 65x, and could detect no nebulosity at all anywhere near it. Again I think it was just too bright low down in that direction, or - not impossible - it wasn’t even Alnitak I was looking at. I don’t have a finder for this scope yet and I hadn’t been particularly fussy about how well-centred my alignments were.

I decided to sweep around aimlessly off and up to the left, at 36x, and found a very nice long-triangular arrangement of stars. Every time I switched up magnification, 65x then 108x, more multiples appeared, different colours, now totally entrancing! Gems in the firmament. As I was staring I jumped! A monstrously-bright squarish object suddenly appeared top right and shot directly across my field of view – the ISS! It was too fast for the scope so I grabbed my 15x56 binoculars and followed it across until it disappeared behind the house.

I moved on to Betelguese then Aldebaran to enjoy the orange colours, I would have gone for the Pleaides and Ally’s Braid but they were now just about behind the oak and I had to be in by 9pm.

The Great Bear had started to appear from behind my house parapet, so I thought I’d see if I could get M81, almost straight up. I’ve never seen M81 before, and after not seeing the Flame Nebula earlier I held out little hope. I checked the scope could point that high without violating the mount, checked the dovetail was properly secure, pressed “View Object” and had a look. My goodness.  There it was. At 36x it was an obvious patch, even more so when I went to 65x. By the time I’d got the 6mm in, unfortunately there was nothing to be seen: the clouds had come. M81 had properly teased me.

The point of the session was to give the new scope a very quick go and get some practise with it, and to be fair the first couple of targets were disappointing, though nothing to do with the scope itself, I think, just poor selection of targets. As soon as I moved up and away from the SW horizon, it became magical.

This scope is a beauty, day or night, and the quick “try-out” session really also bonded me to my TV Delos 6 and 10 eyepieces, about which I’ve had doubts before. Obviously I need a better mount for it, though it’s good to know the Supatrak can handle it, and higher-power eyepiece/s also beckon. Side by side comparisons with the Mak 127 will also be interesting.

Cheers, Magnus
 

[John]

Nice report Magnus

I own a 130mm F/9.2 APM/TMB/LZOS refractor which is like a bigger, longer version of your 105. Same focuser and finder arrangements and sparkling performance

LZOS make exquisitely good objective lenses

[Paz]

A dangerous post that may incite wallet busting behaviour in astronomy households across the country! ?

[Stu]

Sounds like a winner Magnus. I was quite tempted myself! My apologies for my part in your purchase

Look forward to seeing it at a meeting soon!

[Captain Scarlet]

Second Light...

Read my OP above and you’ll notice it wasn’t all sweetness and light, there was disappointment too, which I put down to low positioning of various targets low to the bright South West. Another thing, and which I didn’t include in my first report, most likely being in honeymoon-period denial, was the fact that looking at very bright stars showed me some small aberration, in the form of small radial spangling which wouldn’t go away no matter what I did with the focus. This wasn’t apparent on faint stars.

Over the week this “grew on me” - in a bad way - and the only thing I could think of as responsible, other than it being out of collimation and having to go back (please no!), was the large amount of dust resident on the objective. The aberration was particularly noticeable with the DeLite 18.2mm, at 36x, on Polaris.

Now I’ve read that dust shouldn’t really affect things until it gets ridiculous. But the seller did mention that he had never touched or cleaned the objective in the decade or so he’s owned it. I thought perhaps that there was more than dust on the front of the lens, so decided to some very ginger investigation.

Using a bulb-type “blower” on the dust had no effect at all, not a single speck moved. Interesting. Next, with a very fine make-up brush, I extreeemely gently wafted the hair-tips above some dust and straight away several smeary streaks of gunge appeared: the dust was basically glued to the objective with years of pollen-type gunk. That, to my mind, might certainly affect an image.

So I soaked a small soft artist’s brush with a mixture of propanol and distilled water, and gently deposited around until most of the objective was wet, being careful to produce no movable droplets. Gently, and slowly, I managed to lift it all, and finally found myself looking at a clear piece of glass. The big question was, would it make any difference?

I didn’t have long to find out. Last night, Sunday 31st, was clear, and very similarly dark, 18.8 ish, to when I gave the scope its First Light.

The difference was actually unbelievable. As soon as I looked at Polaris for my night’s alignment, the aberration was gone, and there was another difference: the background was much blacker. First Light (pre-clean) gave me a background of a sort of soupy orange colour, which I’d put down to light pollution through a low-magnification wide-field scope.

Rather excited and relieved, I immediately started on a tour of double stars, using the built-in SynScan list, finding my way to 54 Leonis, Algieba, Castor, Cor Caroli, Kappa Bootis and Mizar. Travelling up the magnifications, 36x => 65x => 108x for each one gave me more pleasure than I can express in words.

Cheers, Magnus (happy again)
 

[Stu]

Excellent result Magnus. My Tak is heading that way too, due a clean which is something I always dread doing!

[John]

Well done Markus - I take a very deep breath before cleaning a quality refractor lens.

My TMB/LZOS 130 is still spotless I'm pleased to say but I have had to do other refractors from time to time.

It sounds like the collimation is good with yours as well - thats always a concern with triplets.

[Paz]

Well done for diagnosing this and having a go at fixing it. It's very useful to hear your before and after observations.