John

A good quality O-III filter delivers quite a bit more enhancement than a UHC on some notable nebulae including the Veil Nebula and the Owl Nebula.

2 minutes ago, johninderby said:

I use a Baader prism on my classical cassegrain and Scopetech 80 where they are ideally suited. 

My Made in Japan Scopetech 80 f/15 is indeed intended for straight through viewing, hence the long drawtube. 

One thing I've sometimes wondered about refractors with thinnish diameter long drawtubes is, with a diagonal in use and the drawtube therefore racked inwards to take account of the diagonals light path length, is there any possibility that either the inner end of the drawtube or the baffles within it could clip the light cone from the objective ?

5 minutes ago, Franklin said:

How does the 130 ride on the HEQ5 John? Must be about 12kg on there.

The scope actually weighs in at 9.5kg so it was well within the capacity of the mount from that point of view. The length of the tube put the mount under more strain than it's weight.

After trying a Celestron AVX, the HEQ5 and a Vixen GP-DX, none of which were really totally satisfactory with the scope (the AVX was actually the best of those 3) I decided to go for a heavy duty alt-azimuth mount and was very lucky that a T-Rex mount came on the market around that time. That does the job beautifully well 

M 42 is spectacular for us but it looks rather puny compared with NGC 604 in the Triangulum Galaxy M 33. If that nebula was within our galaxy just think what that might look like !

NASA put this movie together from Hubble and Spitzer imaging:

My dream scope for years was something like Sir Patrick Moore's 5 inch F/12 Cooke refractor:

And a few years ago I was lucky enough to be able to buy something similar

Except that mine is .1 of an inch larger in aperture than Sir Patrick's

I've just come back from a great evening observing with Bristol AS buddies at the society observatory south of Bristol.

4 of us took scopes along ranging from a 102mm Maksutov-Cassegrain to an 11 inch SCT.

We just toured some well known late Summer / early Autumn sights. Nice to see all 4 gas giant planets through a variety of scopes.

What was really nice though was to be out under a dark sky again with others who share the interest and enthusiasm. I now realise just how much I've missed that over the past 18 months.

What an interesting discussion 

I've no idea what the answer to the original question is

I'm sure glad that I have my 12 inch dob as well as my refractors though

I use the excellent Baader T2 Zeiss prism with my Tak 100 but that is F/9. Not sure that prisms are quite such a good option for faster refractors

Personally I stick to mirror diagonals for my faster refractors. The Stellamira 1.25" looks the same as the diagonals sold under a number of brandings including William Optics. They are nicely made and work very well. The only exception is that the design uses a rather thick ring internally where the eyepiece holder joins the body. This can vignette the field of view when used with eyepieces approaching the maximum field stop size for the 1.25" fitting eg: 32mm plossls, 24mm 68's etc.

I use a clone of the Hyperflex 7.2mm - 21.5mm quite often despite my other eyepieces being Pentax and Tele Vue's. Accepting the restricted AFoV at the 21.5mm end, it's optical performance is rather good for what it cost. It works very well with the Baader Q-Turret 2.25x barlow lens as well giving a useful high power zoom range of 9.55mm - 3.2mm.

The zoom is also great for outreach / star parties.

7 minutes ago, Lurcher said:

Great report John. I saw this for the first time myself on Friday the 1st October.

It's a beautiful sight isn't it? Mirach is such a beautiful golden yellow colour which is a really nice contrast to the faint and whitish grey smudge of NGC 404.

Thanks for posting. I haven't posted anything on here for ages, but your report has prompted me to. I've tried attaching my sketch of it, but not sure if it;s worked. Apologies if it hasn't. I'll try again in the sketching forum. 

Thanks again for posting.

Lovely sketches !

39 minutes ago, SuburbanMak said:

Congratulations! Its a breathtaking object & sounds like you have great views and the equipment to enjoy it at its best. 

Interesting to note in the thread above a couple of folk saying they could see a green colour when younger or that their kids can see the colours. I came back to astronomy after many years and had a distinct memory of the Orion Nebula as glowing green - now at 50, its all just grey mist & shadows...

Clear skies! 

I've noticed, when doing outreach events with my astro society, that it is often the younger eyes that can pick up colour tints more readily than older folks can. Maybe younger eyes are more receptive to colour ?

52 minutes ago, Ian McCallum said:

The $64,000 question!😂 I was looking at the 12" Dob range, but haven't seen what I really want in stock, plus the thought of a really heavy behemoth puts me off, a bit. I know I could build a trolley of some sort to wheel it out, but I don't know if that's the route I want to go.

At least, through your questions and threads, you are getting a good idea of the various strengths and weaknesses of the different scope options

The slight irony is that, if you didn't have a scope at all, the 200P dobsonian (that you have already) would probably be recommended by many as a very good all round scope for visual observing !

Another out of production eyepiece that might be worth looking out for would be the Tele Vue Nagler 2mm-4mm zoom. In your 60mm F/6 refractor that eyepiece would give you 90x - 180x. A very useful range and a high quality eyepiece.

I think I caused this confusion by picking the wrong name for the material used in commercial dobs. Sorry about that

Thinking back to the last one that I owned (Meade Lightbridge 12 inch) I recall that the mount was made from chipboard with a white laminate coating. The Skywatcher and GSO dobs that I've owned in the past have mounts made of the same material.

I think MDF (Medium Density Fibreboard as I now know it to be) might have been used by Coulter Optical for the dobsonians that they marketed back in the 1980's but I'm not 100% sure.

Still here.

Good to hear some reports from those who have clear skies though

1 hour ago, Peter Drew said:

Which Dobsonians use MDF?  All my commercial Dobsonians, Orion USA and Skywatcher are chipboard covered with a sort of melamine coating.

My mistake - I thought that material was MDF. I now realise that MDF is fibreboard, rather than chipboard.

The material that the commercial dobs use is heavy though.

4 minutes ago, RobertI said:

Go to the top of the class John! Well spotted, I had realised after I posted,  but I didn’t want to spoil the punchy headline! 😁 I’ll see if I can change it. 👍

I wouldn't worry about it - I made exactly the same categorization a few years ago 

Great stuff !!!!

Filters sometimes really do earn their keep

Don't want to spoil the thread title but I think the Veil is a supernova remnant and the Crescent an emission nebula

Raining now here

Glad somebody's getting some views though

29 minutes ago, Stu said:

Did you mean M31 John, or M33?

Oops !!!

I meant M31 Stu.

I've corrected it now - thanks for the sharp eyes

I tried my 13mm Ethos (not quite a 2 inch eyepiece but the size of one !) with a C5 once. The views were spectacular even if the combination looks a little comical

6 hours ago, Epick Crom said:

... It's always a special feeling to observe objects in another galaxy 🤯......

It certainly is. I'd like to see some more !

I've tried a couple of times to see the globular clusters that are visible to amateurs in M32 M31 without success, so far. There are a few other posibilities within M33 as well when I have my 12 inch dob out again. This Sky & Telescope article highlights some:

https://skyandtelescope.org/observing/triple-treasure-in-triangulums-pinwheel110320150311/

And this Sky@Night article, some more plus the M32 globulars:

https://www.skyatnightmagazine.com/advice/skills/how-observe-neighbouring-galaxies-local-group/

Thanks for the reminder.

I was going to go to my society observatory to observe this but that has been scrubbed due to the poor forecast. I'll have a scope on standby in case there is a clear patch but more out of hope than expectation

1 hour ago, johninderby said:

The mdf dob bases do indeed suffer if they get wet but the dampness inside covered storage shouldn’t be a problem and should last for years. Best thing is to build a marine ply dob base which will last indefinitely but proper ply isn’t cheap nowadays.

This sort of mount is highly recommended by me

Quality plywood is an excellent material plus it weighs quite a bit less than the MDF used in the stock mounts. The mount on my 12 inch dob is baltic plywood and weighs around 10kg: