Wednesday, April 23, 2008

"2nd" light with the 18" Obsession

Yesterday evening I had my "2nd light" with the Obsession. Again a nice success, as the tracking and the goto were performing well this time. The issue was just the ArgoNavis cable, it was not fully plugged in the ServoCat. So problem solved - all works well.

The speed of the Goto is amazing. Much faster than with my 20cm Newton. Also, with a Dob you don't have the issue of crossing the meredian, something I continuously faced with my Newton on a German mount.

The accuracy of the goto is not bad, all object were in a FOV of 30'. But it can still improve with some of the AN functionality. Something I will have to find out by reading the manual.

I'm still not very confident in moving the scope fully assembled (with UTA). I use the red spring clamps to hold everything tight, but I'm not yet sure if this is totally OK. For now I prefer to observe close to my home. But there I have quite some issues with a street light. Once I'm more confident I'll move at the back of my garden, it's much darker there.

Today I had also dew on the secondary. I did not fix the dew heater yet (not sure which type of glue I need) but I feel the pressure now to do it quickly. Unfortunalty, the whole weekend I'm out, so it will be something for in 10 days.

So far the technical stuff. In terms of observation I limited myself to the classical objects (using goto) such as M3, M51 (spiral arms visible), M81/82, the Whale, M65/M66, M65, Markarian Chain and BlackEye. Naked Eye Limit Magn was 4,5, maybe 5.0 at the end of the session.
After something more than an hour observing clouds were appearing (at the same time as the dew ...).

As a conclusion: everything works well (it's a relief), and now I need to increase the observing comfort and start to migrate at the back of my garden.

Ckear skies to all of you


Sunday, April 20, 2008

First light with Obsession 18"

Last week Thursday my 18" Obsession arrived at home. I ordered it directly from Obsession. I have spend a few hours to assemble it, and had kind of a first light on Friday. I could see the moon behind the clouds. As such not very spectacular, but it was my first look through my Obsession.

On Sunday I installed the ServoCat and ArgoNavis. And finally, in the evening it was more or less clear for an hour or so. At least clear enough to test the scope. And it was a success.

The first object was Saturnus. Woow - so much bigger than with a 20 cm scope. Then Mizar-Alkor. What a difference with my previous scope. Star images where pin point sharp.

Then I've set up the Argo-Navis. It worked!. M3 was really amazing - so many stars (it's not even completly dark). Then M81, M82 (woow). M36, M37 (very nice) and M36. At that moment the sky was completly covered by clouds. I still wanted to hunt M3 in an open area, but sadly one of the encoders was slipping.

What did not work was tracking. The scope was not tracking the objects, so I had to adjust manually. I need to go through the manual to see how this works.

Anyway, It was a successfull first light. I did not expect the Argo-Navis would work that easily from the start.

Clear Sky