PeterStudz

14 hours ago, Chaz2b said:

A couple of toilet rolls, some gaffer tape and Hinckley C will be complete!

Not forgetting a bit of scrap plywood for the reactor core and we have fission. Not quite finished but it works! 

17 hours ago, PeterC65 said:

That would be me!

I'm 18 stone and while the Geoptik Nadira Observing Chair as standard did take my weight, I found that the upright part flexed quite a bit, especially on the top two seat settings. I didn't feel safe, particularly outside in the dark at the edge of a terrace. The seat itself is also very narrow and so not that comfortable.

I am pretty handy with woodwork and could have made a chair but the price of a sheet of suitable plywood was more than the cost of the Geoptik Nadira!

There is no need to go to the lengths I did though. The upright just needs reinforcing with two lengths of wood fixed along the edges and a wider seat added on top of the existing one.

There’s some good info here. I do “woodwork” too and my woodwork shop is an old wooden table next to our bunny cage. Of course the “shop” is only open if it isn’t raining. 

And the price of wood has recently skyrocketed. Even more so than astronomy gear. I’m surprised that the chair hasn’t gone up, although now it’s very good value!

Completely unplanned session for me in Southampton. For some reason I woke up at around 2am and after a good 30mins trying to get back to sleep I gave up and decided to have a “quick” session with the  200p Dob.

Seeing good although transparency iffy with some thin high cloud. Highlight for me was Jupiter, probably the best I’ve seen it this year and I could crank up the magnification. Plus the icing on the cake - a surprise shadow transit of what I think was Europa which I noticed around 3:45am and continued to watch until the sun started to rise. I do enjoy shadow transits. 

Finally went to bed at about 4:45am at which time I slept like a log. Mind, I’ll probation regret it as I have promised my daughter a camping in the garden observation night this evening/tomorrow morning!

On 02/08/2022 at 13:47, Louis D said:

At what power were you observing it?  If you push the power up to at least 200x, you might start to see some outer straggler stars and brighter core stars resolving as twinkling pinpoints of light.  Globular clusters take power and aperture really well because they start to resolve at high power in large scopes, which cuts through light pollution.

I’m in Bortle 7 and I do exactly this with my 8” Dob. Eg on M13 at 200x I can see dozens of stars as twinkling pinpoints of light. It can look stunning, although some nights are far better than others. At high magnification like this I’ll put the globular just outside the FOV and watch it drift through the eyepiece with stars twinkling away. 

Thanks John! For securing the base I had thought of simply getting some smaller rubber feet and replacing what I have (the cost is minimal). Or making a couple of small plastic/rubber/wood “studs” that are fixed to the bottom of the Dob. Obviously shorter that the Dob feet these would fit into a couple of raised recesses (blocks of wood with a hole) on the top of the platform. For the “studs” I’ve had my eye on synthetic corks from wine bottles. Although I’d need to drink another bottle of wine 🙂

I’m in the south to south east of England and I wouldn’t say it’s been that great. Daytime is generally fine but as soon as we get that dark sunlight it goes cloudy 🙁

Saint-Clair beach Southern France, Bortle 5, 11pm, 29th July 2022. iPhone 12 on tripod, single 30sec shot with standard camera app, edited on the phone using Lightroom.

Skywatcher Skyliner 200p, BST StarGuider 12mm, iPhone 12 single shot taken at 3:50am on July 17th, handheld at the eyepiece using burst mode, simple basic editing in the stock camera app. 

Almost there. I lost some time due to holiday but once you’ve cut out the boards and aluminium arcs the whole thing quickly goes together. My Dob has a rather “solid” DIY base with large feet and I haven’t quite worked out how to secure it. But as soon as I had something that worked I could not resist giving it a go, the Dob just carefully plonked on-top. Didn’t have much time before the forecast clouds came in so I homed in on Saturn. Even at 300x (far too much for a sharp view) I could keep the planet centred. Went in to make a coffee and even after 4-5 mins Saturn (some drift of course) was still in the eyepiece. I could even make out 4 moons (a first for me), the advantage of having more time to observe before having to nudge. Now, just need to finish it off!

Nothing that different from the excellent instructions. And I have to say that @westmarch should get some sort of prize for this thread.  I know he’s taking ideas and inspiration from others but this platform is minimalistic, simple and straightforward to make that just about anyone can give it a go. All in the tradition style of the Dob. The only tools I used were a handsaw, hacksaw, electric drill, file, and some screwdrivers.

I did break a drill bit when drilling the fixing holes for the aluminium block, the end of the bit stuck fast. Cheesed off I went down the shed to see if I could find something as a substitute. In the end I used a scrap plywood block, a couple of penny washers to form a recess and a dome nut to sit on top of an M12 bolt. The dome nut is 18mm diameter which is similar to an M20 bolt with the threads filed off . Seems to work well with a smooth rotation.

I’m a veteran of the EQ1 motor drive. I had one for an EQ1 (my first telescope) and it was the best £28 I’ve spent in astronomy. It transforms the EQ1 into something useable. Although I did try and improve it by replacing the 9v battery with something with more beef and that’s rechargeable. I did find that I was going though 9v batteries far too quick and that this small battery didn’t do that well in the cold. For this I used a cheap 12v sealed lead acid battery (the type used in alarms) knocked down to 9v with an equally cheap converter. This pushes out a steady 9v almost whatever the temp and lasts an age before needing a recharge. I also added a little voltmeter over the motor terminals - the idea here (I know it’s not quite as simple) is that I could quickly dial back a motor speed that worked. Oh, also a proper size “knob” on the potentiometer. I’ll change the wiring around somewhat  but it’ll basically stay the same with a battery box on the lower board. I was also going to use a micro switch for a motor stop but playing around I felt that for security it does need some sort of physical stop. For that I just added a couple of wooden blocks and I might still add a micro switch on top of one of these.

PS - my drill can take a 25mm bit. I was wrong there! 

Had a good night/morning mainly on the planets. My daughter sleeping in the garden. Saw the ISS and messed around with our binoculars. Lying down is a good way to go with binoculars.

Small bit of sleep then up at 2:15am. Saturn, the moon and Jupiter strung out in a slight curve (later followed by Mars) looked stunning. Seeing was OK but could have been better. Certainly not as good as last weekend. Viewed Saturn, the moon and Jupiter. Could make out the GRS and the shadow transit of Io. I do enjoy shadow transits.

Finally finishing on Mars, but my daughter had gone back to bed by then. Picture below taken at 4:55am. I had to use the iPad camera as I wanted the phone as a Push-To on Mars using PSAlign Pro.

And when the sun got up I put the solar filter on and we both had a good look at the sun. Seeing decent and there are a bunch of unusual sunspots. 

Not much sleep and it’ll probably take me a few days to recover!

2 hours ago, westmarch said:

Hi Peter,

It is a wide bolt and intentionally so. The Southern pivot carries a significant part of the weight of the whole rig. You can use a smaller bolt but risk it eventually digging out a pit in the softer aluminium block. I wanted to avoid the risk of judder from that. 

Good luck with your build. 

John

Hi John,

Thanks for getting back to me. I’ll think I’ll have to limit it to an M12 - that’s the biggest bit that my drill can take! 

Just started on mine. Just one question - in the instruction documentation by@westmarch the southern pivot bolt is given as M20 - that’s rather wide/large bolt! - I’m guessing it should be something like M8, possibly M10.

Just finishing off the segments. I stuck down the paper template to the aluminium with some craft glue to make things easier for me. Will soak it off in WD40 when done. My woodwork is OK but I’m a bit rubbish with metal.

I’m a bit late to the party but this has got to be one of the best, if not the best, threads in the DIY forum. 

I really enjoy observing the sun in white light. I have one of the filters in your link and I’ve also made my own using a sheet of Baader film. I also discovered that my 10yr old daughter does too. I’d say she enjoys it more or as much as DSO, but then we live in Bortle 7.

I only got a filter in order to see the partial eclipse. After all, I thought, sunspots are just spots and can’t be worth the effort. However, I was wrong. If you get a nice set of spots with decent seeing the spots almost seem to be alive. There’s also a kind of 3D effect (not sure how else to describe it) which you don’t appreciate  in white light images. There are also other subtle surface details.

I haven’t got a green filter nor a Continuum filter (although will probably get one). However, the light pollution filter that I purchased ages ago and decided was virtually useless for some reason brings out solar features and improves contrast - I haven’t  a clue why!

Near to my home much of the New Forest is Bortle 4. Maybe not dark enough for what you are after but it’ll be a significant improvement from your home. Plenty of campsites, a few not that far from a pub. And there’s quite a bit to do during the day. The seaside is not far away too. 

And if you are there in the autumn or possibly late summer, I might be able to take you in a fungi walk. It’s one of the things that I do

Sunspots from morning, about 10:15am, of 11th July.  
 

Skywatcher Skyliner  200p, BST StarGuiders 25mm & 12mm, Baader solar film filter, no-name smartphone holder, iPhone 12, single snap with stock camera app, basic editing with camera app, mono with pseudo colour added.

I am hardly experienced at viewing Mars having only tired 3 times this year within the last month but here’s my experience. I’m in Southampton which is Bortle 7. And for planets I don’t think going somewhere darker helps much, although it could help with heat haze rising off buildings. 

When I first tried about a month ago Mars was obviously tiny, but the southern polar ice cap stood out like a sore thumb. It seemed to glow. Just like snow and ice on the top of an alpine mountain in the morning which I’ve seen myself. And I could just make out some surface markings.

On the second occasion I could make out the ice cap but it seemed smaller, certainly less pronounced. And I could just make out some surface markings.

Last night, the 3rd time, the polar ice cap was all but absent, but I could just about make out a tiny white spot. I’m guessing that the ice cap is shrinking. Also some surface markings. And compared to a month ago Mars had got bigger, well, not quite as tiny.

And out of interest. My best views were all well after sunrise. So much so that I could not even see Mars in my 9x50 finder and had to rely on push-to.

I was observing in Southampton - white light relatively late this morning (10:30 -11:45) and given the time seeing was very good.

That is stunning! I think it nice to see your progress on this over the months. Well done!!!

17 minutes ago, Mr Spock said:

Have the 102mm out now looking at the sun. At x118 the two massive sunspot groups (plus lots of smaller ones) have amazing detail when the seeing steadies for a moment. 

I agree. I’ve been looking at the sun too at around x100 in the Dob and those two massive groups are beautiful. Normally by mid-day things turn a bit pear shaped seeing ways but it still looks good!

1 hour ago, Kon said:

I am glad you got to observe it. Yes seeing was pretty good last night. I was too tired from the early mornings to have stayed up. 

I know what you mean. And for me a late night like I’ve just had will literally take me 3 days to fully recover from. 

I would have been observing that at exactly the same time. My daughter had a friend over for a sleepover and it was a good (if long) night with a real improvement in seeing. Especially later on. 

Also got to see Io appear at the limb which looked stunning too. 

Or is that just a very small man? 🤔

10 minutes ago, DaveL59 said:

building a dob-toppler I'd guess? 😉 

Yes, you guess wisely 😀

I have a sheet of aluminium, an aluminium block, four pillow bearings, a steel shaft and a flexible coupling.