/ Observations

First Light with SkyWatcher FlexTube 250P Dobsonian

It's taken nearly three months for the the SkyWatcher FlexTube 250P Dob to arrive. It seems the whole of Europe ran out and we needed to wait for a shipment from China. First Light Optics were excellent and kept me up to date with the progress, I was even told exactly when it was on a shipping container so I could worry about it out at sea. Assembling the scope is pretty straight forward and comes with all the tools required.

Here's me in action...

The first upgrade was to replace the supplied straight through finder with a right-angle correct image finder and to attach my Telrad with a 2" riser. I'd ordered BST StarGuider 8mm and the StarGuider 2x Barlow. I figured those plus the surprisingly good stock 25mm and 10mm Plössl eyepieces should do me for now. Once the finders and eyepiece were in place, I found the scope to be quite top heavy and I need to make good use of the friction handles to keep it in place. I'll be adding weights and magnets to improve the balance. I used a cheapo laser collimator and did rough finder alignment using a distant pylon.

Before first light, my son was looking at the scope and decided it needed a name. He came up with "Larry", so Larry SkyWatcher it is.

2017-7-17 First Light

Sunset 21:45. Lunar: 22 days old 56° Waning Gibbous
F=1200, D=254, f4.7. "Larry"

22:30 Jupiter

EP: 25mm, 8mm. Seeing: 2-3/5, Transparency: Too early to tell.

I'd left the scope out all afternoon sat by it in a garden chair waiting for it to get dark. I'd planned for my first target to be Polaris to further line up the finders, however sitting out in the garden, something big and bright in the west appeared, so Jupiter was the target of first light with Larry.

Jupiter was a bit low at only about 15˚ and there was quite a bit of muck. No GRS and all a bit fuzzy but I could make out 2 or 3 layers of cloud. At low horizon the mis-balance of the scope really showed itself and I had to have the friction grips set to "gorilla" to stop the big end sinking. I could see two moons to the West and one to the East. I could make out a feint star to the left which turned out to be HD112449. I thought it may have been Calisto as I could only see the 3 moons but Ganymede was transiting.

22:45. Polaris. Alignment and collimation

Now I could align my finders correctly - it looks like I'd done a pretty good job with the electricity pylon and everything was nearly dead on. I put the 8mm in a 2x Barlow for star collimation and again, it seems I'd done pretty well with the laser collimation as I was show steady concentric circles when slightly defocussed. This is the first time I'd done a star collimation check.

23:30 M51, Whirlpool Galaxy

EP: 8mm. Transparency 5. Seeing 4

I thought Rosse's Nebula would be good start as I'd recently visited the Leviathan of Parsonstown, the 170 year old 72" telescope that Lord Rosse use to first identify spiral structures in galaxies.

It was very feint to me and I wasn't sure I was even seeing M51, it may have been too early in the night and it's pretty light in the north. I'm not brilliant at star hopping yet. I intend to get brilliant at it. Also the neighbours still had their conservatory lights on so nothing was quite dark. I decided I'd point the scope at the darker sky in the south...

00:00 M27 "Dumbbell Nebula"

EP: 25mm. Transparency 5. Seeing 3. Vul

Using Alberio as a starting point, I hopped to Vul 13 and then straight to an easy-find M27. At first sight it does look a lot like a dumbbell but further averted vision observations revealed its fainter circular structure.

Side note: At this point I dropped my head torch which broke into bits and I let go of the scope sending the top end slamming down on the bench. I really need to get that balance sorted!

00:30 M57 "Ring Nebula"

EP: 25mm. Transparency 3-4. Seeing 3. Lyr

At first I thought the edge of the stock 25mm had rubbish clarity but of course it turned out to be M57 and not an out of focus star. A mate on the train two days later told me he did exactly the same thing.

M57 seems oval and greenish with a non-uniform bright edge. I was unable to make out the core star. A bunch of Mag 10 stars visible in the field of view.

00:45 M51 (2)

Back to the Whirlpool for another go and I able to make out the two sections of the converging galaxies. I'm looking forward to seeing this in a good dark sky and I'll try to describe what I'm seeing better. This observation reporting lark will take practice.

00:55 M13 "Hercules Cluster"

To finish off the night I went to an old binocular favourite. A real wow moment in my new scope. I've only used binoculars plus a frankly not very good 130EQ and I was blown away. What a super pretty thing. This turned out to be an excellent end to pretty successful first light but alas with work only a few hours away, bed called.