Fraunhoffer

7 hours ago, bosun21 said:

What do you use for the above please? Thanks.

Ah yes, i would like to know that too please. I was thinking of trying to diy something from some resistors / old heater bands and discarded pc fans, but if theres something ready made ......

I love going out in the cold to observe the night sky in person. It brings my senses alive.
The feel of the cool air on my skin. Its quiet, and the noise of the day has subsided. There is no rush, I can take my time. I can hear leaves drop softly to the ground as autumn approaches. In Spring there is the occasional waft of a night scented flower. Sometimes, I hear an owl in the distance, a frog in the undergrowth or a moth flutter by. As I gaze into the night sky in wonder, my heart rate drops and I reach a meditative flow state. I take out my small sketchbook and start a simple drawing. As I draw I see more - everything becomes clearer. Its as though time stands still as I connect with the universe. There is no time, no distance - only the stars and planets before me. 

(written in person and not with GPT 🙂 )

34 minutes ago, Phil Fargaze said:

You have mentioned most things I think of when I`m out camping with the dob. Here is a list of what I usually have for an autumn or spring trip. 

Custom made ground cups to stop sinking into the ground. Small groundsheet to go under the base. I find that underneath, base can get very damp from dew.  A waterproof cover with pegs and bungees to peg down and wrap around the scope. Pre made garden bench covers can be a good fit or just a regular tarp. Old towels to wipe things dry when there is a lot of dew about. Folding camping table (frequently two tables) and chair. Some way of keeping observing notes dry such as a box file or folder with spare pens. If the ground is soggy I have an old thin floor mat to stop the mud getting trodden about.  A 12v hair dryer might need to be deployed on soaked optics but then a power supply would need to be considered.  My dob  has a secondary dew strap so I take along a spare car battery (modern upgrade in consideration!)  Paracetamol for a grumbling back after three hours of bending over to look in the eyepiece. However sometimes I find a low stool can help especially if observing low to the horizon.  Red light head torch.  Hand warmers. 

My dob base is made from chip board so I check it for exposed wood and apply varnish or paint because it can soak up water and start to swell.  

So generally most things are to battle the damp, camping with the dob in the summer is such a luxury, but not so dark.

Thank You. Very helpful 

Hi all.
thinking of taking my Dob on a camping trip and so I wondered what easy precautions I could take to make life easy in a low tech sort of way.
Apart from the usual (too many) accessories......

Im thinking of some bits of plank to stand the legs on so it doesn't sink into the ground and a small trowel to even out any trip hazards, divets etc.
Cover for the odd shower / daytime or be prepared to retreat into gazebo...
Small camping table for the various too many bits and bobs and observing chair / stool.

(this is becoming a long list :-/)

Is a small ground sheet or old carpet tile worthwhile to stick underneath to keep away from the damp ground ?
Anything else / tips ?

Cheers
 

17 minutes ago, SwiMatt said:

Nice sketches! What did you use to have those brilliant colors in Albireo? It's not always easy to get such pop on black  

I really black paper because as you say it keeps a bit of night vision, but also because in the right conditions it can resemble a lot what I see in the eyepiece. For some very diffuse objects that I was putting on paper with pastel on a brush I could even compare how my work was popping with averted vision in the same way as I did in the eyepiece. 

Hi - they are Faber-Castell oil pencils (PolyChromos). I chose them as they come up bright and also i though being a bit water resistant might help.
They are also scuff less than charcoal that I tried before.

I'm trying out some black paper and pencils whilst out with the Dob'
The black paper really helps maintain something of a bit of night vision.

 

I am hoping to take a 12" SW collapsible dob to a star party later in the year and was wondering what the best way to transport it might be.
Apart from its weight and size - Im ok with that - I wondered if anyone had recommendations for what to do when transporting it.
e.g.
- is vertical ok or is the tube best horizontal across the back seats.
- suggestions for soft wrap around the secondary

I don't want the vibration of travel, bumps in the road etc to start upsetting things or loosening the various nuts and bolts (visions of the primary or secondary bolts all coming loose)  or having to spend ages re-collimating /rebuilding it because everything has got out of whack.

thoughts welcome.
 

I dont much imaging but when I do Ive been using an old  Sony camera with old Canon lenses via an adapter.

* As previous post - I was quite surprised to see the amount of coma in the lenses. Its not much, but I was surprised to see any. I think the extreme contrast of the dark sky and pinpoint stars makes this much more noticeable than a daytime photo.
* Its not easy to figure out how to use readily available round filters with the camera lens adapter combo. Much easier with a small telescope.
* I've never been sure if the amount of glass in the camera lenses reduces the amount of light a bit.
* Mounting a big telephoto (that you would normally support by hand) can be tricky. Mine were quite heavy to support just via the camera body screw mounts. Its not do bad if the lens has a foot with a thread somewhere near the CoG (which usually means you can rotate the camera).  Trying to use rings can be pain without fouling or squeezing the focus or aperture ring. Telescope mounting is much more straightforward.
*  Whether its worth buying an expensive one specifically to do this - Im not sure, unless you also have another use for it / birds / ships etc. Or, already have it.

Hope that helps.



 

A lovely report and super sketches. Thank you.

Nice evening here to chill out with some sketching. 

Ive not tried an 80a. 

I do like the way you have been able to capture the bright sunlit parts.

2 hours ago, josefk said:

What a productive night @Fraunhoffer super and super sketches. Ptolemaeus caught my eye last night. Cold wasn't it!

Thank you. It was cold. It was nice for it to be so cold that it was dry though.
I have a an old fur lined 'fishing suit' from a neighbour and some 'charcoal' foot warmers, so I stayed reasonably warm.

I felt like I was floating in space this evening. Nights like this do not come along often, and even though it was cold, and the forecast was expected to drop to -4 C, it was not to be missed. The cold air from the last few days had made the sky very clear so not only were the celestial sights sharp, but the light reflected from the surrounding light pollution was minimal.

The early evening had some very enjoyable views of Jupiter with variations in the belts clearly visible. I was able to reach 250x magnification without the picture turning into a fuzzy blob, thanks to the clear and stable air. No red spot was expected this evening. A tour of the terminator along the half moon provided some wonderful detail of craters, valleys, mountains with long shadows, strange undulating plains and rills. It really felt like I was in orbit and travelling above the surface.

Uranus was not far away and so I thought I would look at this faintly coloured ball. Surprisingly it was accompanied by three very faint dots this evening. After some research, I was delighted to find out these were three of its moons. This is the first time I have seen this. Uranus has a strange inclination so I think the combination of the clear sky and the particular orientation at the current time enabled this.

Orion was reaching prominence due South a bit later and the customary examination of the huge M42 nebula was required. The centre trapezium was very clear, although I couldn’t make out the additional 2 faint stars to make the 6. One day!.  The nebula did not disappoint and under a high magnification the wings spread across my whole field of view.

After an interlude to warm up with some hot soup and catch a bit of sleep, the streetlights turned off at 1am (hooray) and the sky became noticeably darker. Leo was now in the south and so I looked for faint galaxies in this region of sky. ‘Galaxy season’ is almost upon us where we can look out of the milky way into deep space. Despite the extinguished streetlights, the sky was still a bit grey which frustrated my search. However, I did manage to catch several Messier galaxies: M95, M96, M102 and its companion NGC 3384, M65, M66. The nearby NGC 3628 the hamburger galaxy was just too faint to see today.

Comet ‘62P/Tsuchinshan’ was in the vicinity and after struggling with various apps to try and find out exactly where it was supposed to be (it helps to know exactly where it is when looking for faint things) it came into sight as a bright dot surrounded by a faint fuzzy patch. On another night I might try the camera to record a bit more light.

I was by this time starting to feel quite cold and tired, so I finished the evening with some lovely bright star clusters M53 and M3. It only seems a short time ago that I was seeing M3 as an evening object, and here it was coming around in the morning. Where does time go?

Super.

I really am going to have to try black paper.

Do you use a selection of pastels, or mainly one? Im assuming the stars are with a pen? 

On 25/07/2023 at 13:27, Mr Spock said:

Here's my two ready for action. The Dob is next to the shed, and the Tak can go anywhere. Especially useful as my house blocks the East so I can only see there from the top of the garden. The garden runs exactly East to West - North to the right and South to the left 

Now why didn't i think if putting both up in different ends of the garden. 🥴😆. Btw whats your dob sitting on.

A quick sketch from last evening.
A clear-ish sky. It looked pretty milky to me so it was Jupiter and a few clusters. The wind was very blustery, however I did get a nice view of Jupiter in the moments the 'scope wasn't being blown about with a bit of detail in the bands.
I thought I would try a slightly different technique this time. Shading in some black sky and then trying to remove that with an eraser pencil and shield to reveal the brighter areas and then re-touch the detail.
I'm not sure it worked. I need some more practice.

Another fan of a chair.

Also I find the better views are late into the night when the air has cooled down to its overnight temperature and become more stable  and the dew has taken some of the moisture out if the air. I think someone already commented before dawn a good time.

I took up sketching a while back, not because im any good, and i found it helped me slow down and be really patient to see things.

+1 "Left turn at Orion"

Best guide to the night sky i ever bought. 

Nice cover shed.

Just a thought about sealing or protecting the wooden base in some way if it's made of chipboard particle board. Good comments about airflow and humidity drier etc.

I bought a used SW one  a while ago and the base had got damp at some point in the past and swelled. 

Thanks. Forgot to put that in the op.

Celestron c8, with cc (i tend to leave that on rather than keep swapping it on and off), 2x barlow, 10mm uff. Neodymium filter. 

When i put the filter on the barlow or the eyepiece i seemed to get some internal reflections. The reflections were much reduced by putting it on the scope end of the diagonal.

I just liked the S shaped shadow and the valley when i saw this. Since i had my sketchbook out anyway..... It did take me some time to locate it on the map later🤣

Between mare tranquillitatis and mare nectaris.

My local seeing wasnt that great with air wobbling over the  rooftops with everyone's heating on, but i was delighted to get my sketchpad out and get in the zone. 

I tried a neodymium filter in the end of the diagonal which helped a bit.

On 08/11/2023 at 17:59, vlaiv said:

I was going to try and use an old photo exposure meter, but i dont think it goes low enough. I can read to 1.4 lux and with a bit of faffing about with the settings, maybe 0.35 lux.

Plan B is to cross check my mirror less camera with the exposure meter and point the camera with a 30 deg fov straight up at my grey sky and adjust the camera exposure until the 'average' setting says +-0. This should put a sharp histogram peak in the middle. Then work out extrapolating the setting to get another estimate of background lux. in c/m^2

I thought one of the table values from my exp meter might be useful.

Asa 50, f/2.8 , 30s is listed as 1.4 lux., so im thinking by cranking up the camera iso i can get an estimate of sky background. At, least to compare sites.

20 minutes ago, Albir phil said:

I suppose it would give you a measurement of sorts, but in the end sky quality is something we have to accept, are you thinking more like build up your own sky quality maps using the exposure meter. I think it would give you a idea on the night which you could then compare with other nights in the same location.,it is something I thought about at one time but never tried it Good luck 🤞👍

I agree. Not much I can do about it. It would be useful to have something a bit more objective as I search for 'better' places to observe from.
Something more than stepping out of the car and going mmmm 🙂