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Thanks for the feedback everyone.
Several point were made. Here are my thoughts:
1. Eyepieces.
They are not Huygens' or Kellners. They are (super) Plössl, and the focal lengths cover a sensible range: 30, 10 & 6mm.
I had these looked at by some one in York Optical's shop in Melbourne, and I went there with the intention of buying one or two better eyepieces (willing to spend $100 on one), and I let the guy know that I want better EPs. He checked them out in a $2000+ refractor and told me not to waste my money, cos they were fine.
2. Collimation
You don't see nothing like Starkler's image of concentric circles with this thing. I think thick spider vanes dominate the visual appearance of the diffraction pattern. The pattern is not "triangular" though, so probably no pinched mirror. I can see some arcs of circular fringes within the approximately 3-fold symmetric pattern. Adjustments of the main mirror don't seem to improve the pattern (just worsen it if I take it far enough).
As for 35mm film canisters... I presume Starkler has been using digital cameras for a while, because all film canisters these days seem to be made from the same mould and are over 32mm in diameter, so they do not fit the 1.25" focusers. (I do not buy Kodak though, since I found out years ago that they're abandoning the chemical medium of traditional film alltogether, going the hard sell on digital. So much knowledge, down the toilet! What a shame!)
3. The scope is crap.
Thanks Jimmy, for the brutal honesty and well done for getting a refund. It's good to hear some one else bought this thing and found the exact same flaws as I found. I may have been more forgiving though...
After my first look at the moon, I was too excited by the view and quickly sliced up most of the cardboard packaging and put it in the recycling bin. At that point I was committed not to return the scope.
Yes there are many dodgy things about the scope, but you can put up with some defects and work around others.
The mount is very shaky but still usable at low power (30x), and, with a lot of patience, at moderate power (90x). My home made dob mount is a lot more useful.
Several things don't fit, including the finderscope mount. I had to hacksaw one corner of the mount because the focuser got in the way even at extreme adjustment.
I can work with/around all these and several other quirks, but there is one problem I can't solve. I have to quote Jimmy here, because he's _spot on_
"You know at the front of a newtonian...the mount where the second mirror sits the looks like a cross... thats what the stars come out as..... unbeleivable shadowy crap."
Amen brother! _I've been where you've been and seen what you've seen and it ain't pretty!_ You can't actually get a sharp focus. The fuzzy view makes you constantly want to try adjusting the focus but all you get is more blur.
This is precisely what I want to solve. What causes this? If collimation doesn't fix it (and it seems not to), then it must be the main mirror, right? Should I get the mirror out and start grinding away?
I've invested so much time and around $250 in this scope, so I would really like to get to find out exactly what is wrong, and if it's fixable.
It's a beautifully clear night in Melbourne tonight, so now I'm going out to the backyard to check out the setting Moon & Saturn. (making the most of my fuzzy DSE scope :-)
BTW. Can anyone guess who the manufacturer is?
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