timwetherell

11 hours ago, maw lod qan said:

Yes please! More images and details of the design. 

Will post some soon. Ultimate finish will be black but I need to work out the method of attachment to the main scope and machine up the necessary bits before any paint goes on

15 hours ago, spacegalaxy said:

That tube holding the lens looks like a bottle! Also, plain aluminium is the best tube material, it looks very nice!

(P.S. Can you add some more pics? I would like to see them!)

Thanks  yes will take some more pics. It's part of an overall upgrade to my setup. I had a 66mm that wat serving as a guide scope and a finder and doing a poor job of both so moving on to a dedicated 80mm guide and 50mm finder. Will post more pics as it comes along

Much easier to buy one, but kinda fun to make a finder from an old binocular objective  5x 50mm with nice sharp 8.6° FoV

On 27/02/2022 at 10:11, vlaiv said:

Yes you can. It is not as comfortable with slow motion controls, but you can observe.

I have two alt-az mounts - Az4 and dob mounted 8" scope (which is also type of alt az) - both lack slow motion controls, and I use both for high power planetary viewing (sometimes even up to x300).

I'm inclined to agree. A nice buttery smooth well balanced alt-az is probably much easier to use than slow motion controls. You'd have to track both axis simultaneously at differing rates and it might be like patting your head and rubbing your stomach at the same time. I have a home made alt az for quite a big scope and it works quite well just pushing it around - bit more intuitive.

Mine uses ball bearing races to take the actual load and separate discs and friction screws to vary the resistance which works quite well

Yes, every company and every nation will now no doubt want their own starlink and once the night sky is ruined anyway we'll probably end up with space advertising billboards!

The camera needs a real image on the CCD which should sit in space at a distance exactly equal to the focal length of the primary mirror. The eyepiece magnifies this real image and in effect turns it back into a virtual image at infinity. So the optical centre of the eyepiece will need to be beyond the primary mirror focus point by a distance equal to it's own focal length. Which in the case of say a 40mm, is quite a bit. 

Had a set of Huygens eyepieces with my 60mm refractor as a kid. Bought a set of really cheap huygens EPs a few years ago for about £10 just for the amusement putting them in the 60mm finder to remind me what the views used to be like. Of course my equipment's better now but my eyesight isn't a sharp as it was back then!

On 15/05/2020 at 18:55, Mark at Beaufort said:

Tim I believe I saw it last night. @Johngave me a very useful diagram to identify the stars around the edge of M61. Yesterday the postman delivered a Baader 10mm Ortho which gave a better view of the galaxy than some of my alternative EPs. The 12" Dob was situated in a dark site at the end of my garden and I used a black out hood to improve the situation. So I think I saw it - hopefully, it will get brighter over the next few days/weeks.

Well done. yes, i think a 12" is probably the beast for the job. in my 7" I thought I saw something but wasn't able to navigate by those 14mag stars in a row by the supernova because I really couldn't see them. If it's gets to mag 12 or 13 then I'll definitely have another go visually

14 hours ago, rl said:

 

Taken 2200 UT approx 15 may 2020

8" Newtonian, 900mm focal length, 7 *60 sec lights, 4*60 sec darks, QHY183C camera, Orion skyglow imaging filter, centre crop. Galaxy is about 6 arcmin diameter. Supernova is the 2nd star up of the 4 in a vertical line just to the left of the galaxy

Nice shot, caught lots of detail in the spiral arms too!

Thought I'd seen it in the 7" but looking at my sketch it's possibly a bit low. In my photo the two foreground stars below look of similar magnitude so if you saw those too, you almost certainly bagged it! Might have another go tonight

Anyone been watching the supernova in M61? I think I could just see it visually in my 7" scope (possibly with averted imagination!) but shows up well in a 15s exposure

I'd stay up late or get up crazy early for something really special like a transit of Titan, but generally I'm a civilized hours astronomer. If it's clear between tea and my bed time i'll observe if not then I won't. The important thing is to do what makes you happy. Amateur astronomy is a hobby not a duty, so whatever makes you enjoy it most is the right approach. I have a friend who's happy to stay up all night imaging and that great for him, but for me 11pm is brandy and bed time 

11 hours ago, F15Rules said:

That's a lovely image Tim!

What equipment/scope were you using?

Dave

Thanks Dave. It was taken through a WO 66 ed apo. Camera was a sony a7s. 

12 hours ago, John said:

Perhaps a quick re-work of this fine piece Tim ?

 

Actually that's not a bad idea!  I might do that

16 hours ago, Veracocha said:

I saw exactly that. Haven't looked to the stars for years (or been on this forum) but did look up on the same night as you and saw with my binoculars. Beautiful.

It was very beautiful wasn't it! my preferred view was binoculars too, telescope was a bit too 'zoomed in'

28 minutes ago, John said:

ISirius is easier with some light still in the sky. It gets harder as it gets darker. Like many astro observations there is a "goldilocks" period when there is just the right amount of light in the sky to control the glare from the primary while still allowing the much dimmer secondary to glimmer though.

Interesting idea I hadn't thought of doing that. Will give it a try 

28 minutes ago, Barry-W-Fenner said:

No joy for me Mark. I tried to split it. A bit optimistic of me with the 8"

I've split it a couple of times in the UK with a 7" so you should be able to with an 8. It all comes down to atmosphere. When I lived in Australia and sirius was almost overhead the pup wasn't even really much a challenge with a 7", one could see it 90% of the time. Same with Antares, quite difficult in the UK which is a shame because it's one of the most beautiful doubles!

Miraculously we had clear skies last night and was able to see venus amongst the Pleiades for the first time in my life. Very cool, especially being able to see venus' half phase! Anyone else get any nice pics? I was hoping to capture some of the nebulosity but venus was so bright it swamped it.

On 13/02/2020 at 23:44, DavidR100 said:

 

Was your success last year or 2018? 

2018 I believe, it's been raining here most of 2019 :D

16 hours ago, DavidR100 said:

Over two years on ....  I was wondering if you had any success with M69 and M70?

Actually yes. it all came down to local sky quality. Even the slightest hint of haze will totally obscure them and we often have a very slight haze here. But on a particularly clear and haze free moonless night, they were relatively easy! So a bit like sirius B really, all seems to depend on seeing and transparency

20 hours ago, John said:

I have one of those as well. Out of production now apparently but mine has proved much more use than I thought it would be when I bought it

 

yes they're quite good aren't they! I tried a lot of fixed focus super shorts none of which really was a good as the nagler zoom.It's also handy when you're up at the silly magnification end to be able to tweak it up or down just a smidge

I use a 2-4 nagler zoom quite a bit, it's extraordinarily gocd for a short focal length eyepiece! 

On 08/01/2020 at 19:02, LukeSkywatcher said:

One show I saw on TV said that when Betelguese does go SN, the resulting SN or Nebula will completely fill the sky. We wont be able to see anything else.

I imagine if it does go supernova during the initial few weeks it will be like having a permanent full moon so no one will get much of a view of faint fuzzies in that area of the sky! But I think the resulting planetary nebula will be relatively small and fairly dim? There's a bit of discussion about it's size up further up this thread

11 hours ago, JamesF said:

Or if you want it to be, say as big as Jupiter at opposition (about 50 arcseconds?), it would take around thirty years.

 

Yes, good idea to compare with the crab! I'd be thinking crab nebula 1000 years ago now 300 arcseconds across 0.3" per year. Ten times further away but because all the angles are small one can probably just use small angle approximation and say 3" a year (never did have a very comfortable relationship with radians!  ) so maybe jupiter size in decade/s? I imagine it would be very bright though?

2 hours ago, Jiggy 67 said:

Once Betelgeuse does go, it will be that bright I don’t think we’ll be seeing Orion at  all for a while but to see the result will more than make up for it 

It would certainly be the brightest planetary nebula in the sky. I'm not sure how long it would be before it's angular diameter was resolvable in amateur telescopes though?