Thursday, January 27, 2005

The First Night with the Ranger

The sky becomes clearer, and I go out to buy my own tripod due to this reason. I've got a Manfrotto 055C with a 410 geared head. The Moon (half) is high in the sky, and it's bright. I can't afford the time to travel to a dark site, and so I didn't expect too much.

I spend most of the time to look at the Moon, and it's exciting enough. With the highest power available (2x barlow + 6.3mm Plossl), I can easily see that the moon is moving, I've got the feeling that if I were on an space-craft, flying slowly and watching over it's surface. When the wind is coming, I can see the air ahead moving, just like boiling water. To me, I've a feeling that it should be nothing too special, however, it's a new experience for a C90-only owner. I can never see all these before. Many surface features are detectable and they're nice.

Another *new* discovery is that, I can see many many stars no matter where the telescope is pointed to and it's never the case for my C90. Now, I see optical quality wins, even aperture wins too.

The Star Pointer from Celestron work nicely and it can be quite accurately aligned, and the Manfrotto 410 head is excellent too. It's a bit too tight in the first hand but it works great once I use it more - I've already used it *more* enough. Now, I think I've got a decent setup for more serious observing.

Chromatic abberation is serious for the Ranger in day time, but strange enough, when looking at the moon or the stars, the problem is not so severe. I can neglect this problem virtually, since my eyes cannot detect it too much in night sky. Many people don't like the draw-tube focuser of the Ranger, however, I find that I love it and the helical focuser, is smooth enough, but the focus travel is insufficient. Of course, when it's used with the draw-tube, it's definitely enough.

Tracking with the geared head is no problem at 152x. It works nicely even when the Ranger is pointed at the Zenith, no balancing problem at all. When moving the adjustment knobs, it shakes but the vibration damps out quickly.

With the 32mm Sirius Plossl, the view is large and nice. I can never have similar view with my C90 but I find wide field view is still better with the Pentax 10x50, however, it's comparable. The edge performance of the 32mm Sirius Plossl is better than that of the Celestron SMAs, but it's still not up to the level of the 20mm Tele Vue Plossl. The field of view with the 20mm Tele Vue Plossl is nice too, but it's noticeably smaller than with the 32mm Sirius Plossl. The edge performance of the 6.3mm Celestron Plossl is good too, but again, not up to the level of the 20mm Tele Vue Plossl, as expected.

Next time, I should try out some deep sky objects as well as the planets.

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