A great night in 'the dob hole'.

[Mike73]

Had a great night observing last night after what seems like night after night of poor transparency I finally got it good!

I got to my local dark site just after sunset and started unloading the van and walking 50 metres to my observing spot. Each time I did that walk (4 times) I was looking up at the stunning crescent moon, Jupiter and Mars blazing away against a deep blue sky.

So I set up, collimated and sat back with a coffee just enjoying the view. I took a quick look at Mars but the wind was a little too gusty so I made the decision to move back closer to the car where a hedge would give me a little shelter....another 4 walks carrying gear and once again set up collimated but happy that it was out of the wind.

I just had a few targets planned, I've seen all of them before but apart from M51 havent sketched them, the problem was going to be that most of them were very close to the zenith and into 'the dob hole' where nudging a dob gets pretty tricky.

First object was M63 the Sunflower galaxy. Quite bright and easy to find but really hard to make out any detail, just suggestions of spiral arms more than anything.

Onto the great M101. I think my sketch shows the spiral arms clearer than what they actually are even with a large scope at dark skies. It took a while for the arms to appear, I struggle using averted vision to see detail so usually rock the scope which does the same thing but with the dob almost pointing vertical that proved almost impossible but eventually my eyes became adjusted and the spiral arms popped into view and I made the sketch.

M101 has got so much to offer with more NGC's within it but I'II save those for another night when its altitude is a little better.

Next up M51 the Whirlpool galaxy. Complete contrast to M101 the Whirlpool was bright and bold with its spiral arms reaching around to NGC 5195, just the connecting bridge was fairly faint but really wasnt hard to spot. This is the first time I've looked at it with the 16" and it was so much better than when I saw it last with the 12". Just incredible! Enough said!!

The last galaxy for the night was in Virgo, M61 the Swelling galaxy. Fairly small and compact with a central bar pointing from NE to SW and one tuft of an arm visible.

So I think that may be the last chance I'II get for DSO's before the moon becomes too bright. It really was one of the best nights I've had for a long time, perfect transparency with fairly dark skies.

Talking of dark skies, my SQM readings for that site have been alot better this winter. A couple years ago my best readings there were around 21.3 SQ, last night my best average reading was 21.65 SQ! I guess I have to thank Emad and his lamp post for that haha!

[AlexB67]

Nice one Mike. Gorgeous artworks    Emad will not be thinking about his lamp post, he'll be thinking should I get that 16 inch after all

[scarp15]

Terrific session Mike, good to learn that you finally got a night of good transparency, great set of drawings to. I am inspired to try for the spirals in M101 tonight, which is looking to be very promising up here, certainly intend to be situation as far away as possible from any type of lamp post.

[michael.h.f.wilkinson]

Lovely sketches. I feel an acute case of aperture fever coming up

[todd8137]

Very nice some great detail ,we have are group night tonight fterba few demos we off to the dark site hope to get some sketching in fingers crossed

Pat

[Mike73]

Thanks chaps.

It really was the sky transparency which made it special the Beehive cluster looked huge with the naked eye. Just wish there were more nights like it. 

[jabeoo1]

Blimey Mike M51 looks really great.  Sounds like a great night. 

[scarp15]

Interesting to see that you had used X135 whilst observing / sketching M101. I have tended to stay at low power on this (x62, x80), though I have observed M51 in recent sessions with very good clarity at x160 (10mm delos), so will try and step up to medium power tonight. 

[Daniel-K]

Mike was this the exmoor site? i know you said you needed adverted vision to see the arms in M101 but did you manage to pick out the HA regions in the arms? Quality sketches again!

[jetstream]

Glad you had some great skies to observe in Mike,excellent sketching.

[AlexB67]

Interesting to see that you had used X135 whilst observing / sketching M101. I have tended to stay at low power on this (x62, x80), though I have observed M51 in recent sessions with very good clarity at x160 (10mm delos), so will try and step up to medium power tonight. 

Depends a bit what you want to see and how well you want to see it. Some interesting stuff on that site. Try everything in your case  , well to a point.

http://clarkvision.com/visastro/m51-mag/index.html

Not that I ever tested it out on M51 with skies good enough where the smaller exit pupils tend to favour mostly due to light pollution, but out of town had noticed  how some features show up better  in some cases depending on magnification on some galaxies. 

[estwing]

great read mate glad you had a "stunner"

[jetstream]

Interesting to see that you had used X135 whilst observing / sketching M101. I have tended to stay at low power on this (x62, x80), though I have observed M51 in recent sessions with very good clarity at x160 (10mm delos), so will try and step up to medium power tonight. 

If your sky is good tonight I think you will be very pleased with the 10mm Delos on M101 Iain.You will have great object size @ 160x,and good exit pupil for smaller DSO as well with that 10mm.Can't wait to hear your report

[Mike73]

Interesting to see that you had used X135 whilst observing / sketching M101. I have tended to stay at low power on this (x62, x80), though I have observed M51 in recent sessions with very good clarity at x160 (10mm delos), so will try and step up to medium power tonight. 

I dont really tend to stick to a certain magnification if I want to pick out details in galaxies. I usually pick a medium power to make the sketch and use a low power to get an idea of the size and shape then just increase the mag from there and see what else it reveals. As soon as I get to around x190 the view gets dimmer and the arms are harder to see but I can start to see smaller brighter stars within the arms that I couldnt see with low/medium powers.

I didnt do this last night though as it was just to hard nudging the dob!

Mike was this the exmoor site? i know you said you needed adverted vision to see the arms in M101 but did you manage to pick out the HA regions in the arms? Quality sketches again!

I've never been to Exmoor Dan, its about 2 hours away and this site was only 10 minutes from home. Theres darker spots in mid and north Cornwall but I was being lazy and just wanted to stay close to home.

I always rock the dob which usually shows where the arms are and then when my eyes get used to the view I can see them with direct vision. 

I saw both the HA regions in this image, dont forget that the sketch is north down and the image isnt. You've probably got younger and better eyes than me and probably darker skies at places like Lyne.

[Daniel-K]

Wish I could get out.i seem to be constantly on overtime this year! Same story tonight clear forecast but working nights.

[Mike73]

Wish I could get out.i seem to be constantly on overtime this year! Same story tonight clear forecast but working nights.

It will be worth it when you get that monster dob!

[jetstream]

When viewing M101 a while back I saw a close detached "patch" of smudge below the galaxy(in my reflector) is this a Ha region?what exactly is it?In my 10" one arm stood out better,making it look off center or something

[swamp thing]

When observing for extended periods in the Dob hole I tilt the ground board slightly by putting something under one foot. This allows much easier tracking

Great report and sketches mike

[Mike73]

When viewing M101 a while back I saw a close detached "patch" of smudge below the galaxy(in my reflector) is this a Ha region?what exactly is it?In my 10" one arm stood out better,making it look off center or something

Thats pretty much how I saw them Gerry, I saw two fuzzy patches in the arms at the top and bottom, not star like just small fuzzy patches. I mix charcoal and white pastel to sketch the galaxy with and then used just white pastel to show those HII regions but it didnt show up very well in the photo.

I think both me and Dan have got it wrong in saying Ha when its actually HII regions. From what I understand they are just huge gas clouds similar to M42 etc but much much bigger! I could be wrong though (usually am!) and hopefully someone may correct me.

Your right about the arms making it look almost lopped sided, I just didnt show it well in the sketch.

When observing for extended periods in the Dob hole I tilt the ground board slightly by putting something under one foot. This allows much easier tracking

Great report and sketches mike

Thanks Steve.

Now you mention it I remember you saying about tilting the ground board before, just wish I remembered that at the time! Its not much fun trying to nudge a dob up there is it!

[jetstream]

Thanks for clearing that up Mike,very interesting that it is bigger than M42,amazing.If I look at your sketch upside down it looks like when I see M101,but much fainter and not as extensive in detail.In my 10" there is clear separation of the smudge and the rest of the galaxy.What struck me was the one big arm hanging out,with the rest seeming more compact in such a big object.That is great sky you have nearby,fantastic.Great observing Mike

[Mike73]

Thanks for clearing that up Mike,very interesting that it is bigger than M42,amazing.If I look at your sketch upside down it looks like when I see M101,but much fainter and not as extensive in detail.In my 10" there is clear separation of the smudge and the rest of the galaxy.What struck me was the one big arm hanging out,with the rest seeming more compact in such a big object.That is great sky you have nearby,fantastic.Great observing Mike

Thanks Gerry.

When you think that M42 is just 1400ly away compared to M101 which is 22mly away then it just shows how big those HII regions are!

I wouldnt use my sketch to compare the actual brightness of what I saw compared to your views, its really hard sketching under a dim red light so theres no way I can get the actual brightness of my view to be anywhere near accurate.

Dont forget that surface brightness stays the same regardless of aperture, the differences between my 16" and your 10" will come from magnification and exit pupils used.

[cotterless45]

Lovely ! Had an awful night here with blooming awful seeing and glow all around. Managed Panstarrs in CNv.

Starting to think of bigger aperture !

Nick.

[scarp15]

I wouldnt use my sketch to compare the actual brightness of what I saw compared to your views, its really hard sketching under a dim red light so theres no way I can get the actual brightness of my view to be anywhere near accurate.

Dont forget that surface brightness stays the same regardless of aperture, the differences between my 16" and your 10" will come from magnification and exit pupils used.

How long would you consider that you spend on average on each sketch Mike and do you pause and return to the same subject perhaps later in the session? I am asking from a practical  - considering the circumstances i.e.  cold, nudging, risk of over working etc, and observational requirement perspective. I presume that the sketches are concluded (that is to say not developed further at a later stage) during the observational period. 

[Mike73]

How long would you consider that you spend on average on each sketch Mike and do you pause and return to the same subject perhaps later in the session? I am asking from a practical  - considering the circumstances i.e.  cold, nudging, risk of over working etc, and observational requirement perspective. I presume that the sketches are concluded (that is to say not developed further at a later stage) during the observational period. 

It completely depends on the how interesting the object is but I'd say that I usually spend about 30 minutes observing and 15 minutes sketching.

That first 30 minutes is spent with no red lights on and I just let my eyes get used to the object, when I'm 100% sure I know where the detail is I get my sketch pad out and start sketching under red light. I think I must have quite sensitive eyes because even though its very dim I can still feel and see the difference between from when I sketch with the light on or off. This is one of the reasons why I like sketching white on black as the light doesnt reflect of black paper compared to white, same goes for when I used to use a paper sky atlas.

I dont use any fixative straight after a sketch, they just dont work well in the cold. The problem with not fixing is that the next day there are going to be smudges from the pastels so its just a case of using a rubber to clean the sketch up then add the written details down the side and take a photo. I never add anything to a sketch the next day, I think theres a real risk of making a sketch look like you wanted it to rather than how it was which defeats the point of doing all the hard work in the first place!

[scarp15]

Yes that is a methodical process, to spend qualitative time actually observing, so as to build up a familiar visual comprehension of the object and its environment, prior to sketching.

Interesting that you choose to sketch white on blacks. I was aware on Friday evening, as to how sensitive my eyes had become, as when the beam from my very dim red led head torch shone onto the OTA,  the reflected glare was quite significant due to the whiteness of the tube.