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Penguin does the splits....


Stu

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I was chatting to Lorna (aged 4 1/2 ;)) this afternoon and she was asking if she could look at the moon. I told her it would not be up before she went to bed tonight, but that we could get the little telescope out of the loft which her older sister had used, one of the little blue penguin (or rocket?) Infinity 76 scopes.

I couldn’t find the helical focusing eyepiece, so I slid the two pegs out of their slots, popped in a 15mm 70 degree ES eyepiece and we had some fun looking at clouds and bushes in the garden.

Once she had gone to bed, I thought I would see how good (or bad!) it really is with some decent eyepieces. The 24mm Panoptic (x12.5) only just reached focus, but good enough to act as a finder. It was a bit like using a 30mm 2” eyepiece in my Sumerian though, needed supporting otherwise it just flopped down once past about 45 degrees.

I successfully found Mizar and Alcor, looking ok but not particularly sharp. I carefully popped the Nag Zoom in at 6mm (x50) setting and after a bit of faffing around, managed to find a reasonable focus that split Mizar. There was plenty of SA present, sharp focus was tricky and even at best there was a sharp star surrounded by a significant halo of unfocused light. Lots of coma too, pretty much anywhere off axis. Stars needed to be centred to be sharpish.

Next stop Polaris. Hmmm, even at 3mm, once I found it which was not easy even after centring with the pan, and focusing as best I could there was no sign of the tiny secondary. Perhaps not surprising.

The Double Double was my last target as I was getting cold, distinct autumn feel in the air now, shorts probably not wise. Plenty of messing around centring with the 24mm, switching to the zoom, loosing the target and trying again. Eventually I got it centred at the 3mm setting (x100) and tweaked the focus to find the least worse position ;). So? Well it was not necessarily pretty, but the easier pair of the two was a definite split and the slightly harder pair was a probable which came and went with the seeing. Quite impressive for such a bargain basement scope.

Actually that was not quite the last, I caught Albireo in the 24mm and it split cleaning showing some nice colour.

Compared with my TAL Alkor which is a 65mm f7.7 Newt, the optics are nowhere near as sharp. I guess that’s to be expected, a fast (f4) mass produced scope versus and much slower one with renowned Russian optics. The TAL shows no signs of SA and no noticeable coma, the DD is resolved beautifully in it despite the smaller aperture. F4 is pretty challenging though so the level of SA and coma is to be expected. As a widefield children’s scope, and for fun on the moon it is very handy, and the short focal length combined with the ball shaped mount makes it very simple to point and hold position, even at x100, but much easier at x50 or below.

Another bit of fun, thanks for reading :) 

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