10" Dob - first light

[george7378]

I woke up this morning at about 6:30, and the first things I did was look out of the window to check the weather - only to see Orion spread across the sky just waiting to be observed. So, I took the new 10" outside (took the mount then the tube - only took about 2 minutes) for first light.

Using the optical finderscope is quite challenging when I have been using nothing but an RDF for a year, but eventually I centred M42 as the first object for the scope to view. Using the 25mm EP, even under moonlight with the Sun rising, gave the most heart-stopping view of M42 I have ever seen. The first thing I saw about it was the massive expanse of its shape. There were two curved wings stretching out from either side, with a pillar of dark nebulosity cutting into the mottled glowing patch above it. Even though the conditions were not great, the view was breathtaking. I found that I could quite easily pull up a seat, and stare at the details of M42 from a comfortable observing position. The detail within the nebula was so much better than I have ever seen, and thin, wispy structure was unbelievable.

As well as the nebulosity, I noticed two more stars in the Trapezium - much dimmer than the rest. One was between the two stars forming the left side of it, and one was close to the top on the right - here's a picture:

I found that I could ramp up the magnification to 120X with the 10mm and I got an even better view of the nebula's structure, and the trapezium stars were even easier to see. It was getting light by this time though, and the nebula's fainter details were getting harder to see.

I also tried the Moon, and it was plain to see that the optics of this new scope and far better than the 130 - at 120X I could trace the shapes of the mountains, and I could see the ridges and bumps in the walls of craters like Copernicus and Plato, with the former showing an intricate central mountain range and layers and ridges in the walls. The views were so much sharper and clearer than ever before, even when I put the generic 2X Barlow in. At 240X, I could see the individual peaks in the dense mountain fields near the Appenines, and switching between magnifications allowed me to see creases and rilles in the surface, as well as countless small details in the polar crater fields. I didn't expect much of a difference when observing the Moon with the new scope, but the details were immediately razor sharp and I could even see some details on the dark side of the Moon due to the Earthshine!

So, all in all, I can't put into words how pleased I am, and my first half hour of priceless views has already re-paid the value of the scope in 'Wow' factor.

One thing I think I need to do is collimate the scope - I will get it done over the weekend, hopefully. I noticed that the views were sometimes mildly sharper when I looked towards the edge of the field of view rather than the centre, so I think I need to try and align the mirrors better.

[Barry]

Goerge

I'm glad the scope lived up to it's promise. I got a Baader Laser Colli with my 8 inch Truss Dob from FLO. It was very easy to use. Now if only the clouds would go I could actually use the scope!

Barry

[callisto]

Exellent,

Always great to hear the WOW factor on first light of a new scope

[Doc]

M42 is fantastic through a large scope, did the scope show any colour, mine shows M42 bathed in green. Stars E & F are tricky to see and your scope must be very well collimated to split them so again well done and your scope sounds brilliant.

[Moonshane]

really great report! I have been told several times that the early hours often offer far better conditions than the evening.

your drawing of the Trapezium is pretty bang on, see below

[george7378]

Goerge

I'm glad the scope lived up to it's promise. I got a Baader Laser Colli with my 8 inch Truss Dob from FLO. It was very easy to use. Now if only the clouds would go I could actually use the scope!

Barry

Thanks for the advice - I've been looking up laser collimators and they look pretty easy to use. I may attempt to do it roughly by eye first, to see how good I can get it.

M42 is fantastic through a large scope, did the scope show any colour, mine shows M42 bathed in green. Stars E & F are tricky to see and your scope must be very well collimated to split them so again well done and your scope sounds brilliant.

It sure is! I didn't see any colour this time, but the Moon was up and the Sun was about to rise, so the conditions were less than ideal. I will try again at home with a properly dark sky! The view was still fantastic though, and I will really enjoy looking for colour in M42.

really great report! I have been told several times that the early hours often offer far better conditions than the evening.

your drawing of the Trapezium is pretty bang on, see below

Thankyou - I loved writing it after the great views I got. Yes, the seeing was very steady when I was looking at the Moon, and the air was very clear. Thanks for the picture - I didn't know there were that many stars in the tapezium. I doubt I will get the G, H and I stars though!

[Moonshane]

I wonder if the fact the sky was a bit lighter than usual helped in reducing the glare of the main stars and helped in picking out the others?

[Revs]

I'm jealous, George . I stayed up until 2 this morning waiting for the clouds to go so I could have my first light dob experience, but it never quite cleared up. Great report, now I really can't wait

[george7378]

I'm jealous, George . I stayed up until 2 this morning waiting for the clouds to go so I could have my first light dob experience, but it never quite cleared up. Great report, now I really can't wait

Well, you've got it to look forward to I haven't really scratched the surface of what this scope can do yet. I can't wait to hear how your viewings go - please write a report!

I wonder if the fact the sky was a bit lighter than usual helped in reducing the glare of the main stars and helped in picking out the others?

Maybe ... would that not reduce the visibility of the dimmer stars too? Just a guess - I do know from experience that dimming the glare of the bright planets can make their surface details a lot easier to see, so you may be right.

After a bit of searching, I think this picture best represents what I saw (although the tendrils extended further and the centre was not so overexposed) I also spotted more detail in the central region and the dark nebula was more pronounced:

[WayBig]

Lovely report. I've not shown my new dob m42 yet, but am really looking forward to it later in the year.

I had problems with my finder too, I've stuck an rdf onto the top of it and find the combination works well - I use the rdf to get in the right area, then the finder to get closer.

[Makron]

Goerge

I'm glad the scope lived up to it's promise. I got a Baader Laser Colli with my 8 inch Truss Dob from FLO. It was very easy to use. Now if only the clouds would go I could actually use the scope!

Barry

I also use Baader Laser for collimation. But always I try a star test at the end.