Sunday, May 19, 2013

First Light!

As the sky cleared up in the afternoon and an waxing Moon was hanging in the sky, I thought best not to wait for the nightfall, test the telescope right away and make some images – which was a good decision. It was a cold day and later the night it was very cold, as the entire spring was very very cold here (probably due to global warming, hah!) and I really don't feel that good, so I did not went out again at night.

So, only some images of the Moon in the daytime. I used a "point and shoot" camera, which I held by hand to the eyepiece, and I used a bit of the optical zoom of the camera to fill the frame.

At about 17x magnification.
 f=700mm with f=42mm eyepiece

At about 42x magnification. 
f=700mm with f=17mm eyepiece.

At about 70x magnification. 
f=700mm with f=10mm eyepiece.

The images seen directly by the eye were better than what the camera could capture – not much better, but noticeable better. No camera noise, and the eye (or rather the brain) can filter out the movement of the air, and use clues to enhance the perception of features.

I need to clean the eyepieces! And I should remove the reticle from the f=10mm eyepiece. Oh well. :-) At night, the imagea should be a lot clearer without the sky's blue shine robbing contrast.

But not bad for a 5€ telescope! Sure, the eyepieces would cost a lot more, but I had them already, so I still consider it a cheap scope.

While the optics are fine (considering the price), pointing the scope is truly horrible, the az-alt "fork"-mount is awful, awful, awful. I made some slight improvements, so the telescope does not shake that much. Before the modifications it used to shake like a leaf for 2 to 3 seconds, after the modifications it only wobbles a bit for about 1 to 2 seconds. But pointing the thing remains awful. And at 70x magnification, the sky (and everything in it) really moves! The reticle makes that nicely visible. And when I tighten down the screw for azimuth, both azimuth and altitude change by about a third to a half of the FOV of the 10mm eyepiece!

Still, I could see Mare Imbrium half in the shadow. Luna 17 and Apollo 15 had landed there, and carried with them the very first rovers! Lunokhod 1, the first uncrewed rover, and Apollo's Lunar Roving Vehicle, the first crewed rover. And at the edge of Mare Imbrium were very prominent the Montes Caucasus and Montes Apenninus mountain ranges, and Archimedes Crater – the angle of the Sun at the moment really makes them stand out now. Too bad I didn't make a photo with the 10mm eyepiece of that area.

Instead I made an image of the lunar craters in the south. Wow, that thing has some scars!

So much for first light. Despite its deficiencies, this scope is nice.

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