chiltonstar

A good start - doubles are fun to image because you don't need perfect viewing conditions, which some of us in NW Europe don't seem to get very often anyway.

I always struggle when trying to reproduce the subtle colour differences that the eye sees - these seem to work better I find with a small frac as the Airy discs are larger and fainter, and don't burn out so easily as with more aperture. Emphasising the colour contrast with PhotoShop helps!

Chris

Certainly excellent for planetary, the Moon and double stars, but no slouch on DSOs either, although it is only 180 mm. For the latter, a 28 mm or so wide field eyepiece is useful.

Chris

1 hour ago, John said:

Well done Chris

I managed to get the split again with my 100mm refractor at 225x and 257x earlier this week as mentioned here:

As I said in that post, I've found that Antares from the UK, at it's low altitude can present a slightly misleading appearance due, I think, to atmospheric disperson. This "dual colour" primary star presentation can mask the real secondary which I think is more or less due west of the primary and actually appears quite faint.

I'm sure you got the "real deal" though, with your experience, scope and observing conditions

 

Yes, there is always an atmospheric dispersion artefact, usually E or SE of the primary, but this is blurred and doesn't focus to a point, whereas the secondary is nearly due W and does. On previous occasions, I've used my ADC which has cleaned up the primary a lot and removed the artefact, although I didn't last night as I had such a brief observing window because of A's location.

Chis

Exceptional seeing here (Oxford area) last night with Antares visibly twinkling less than usual, so I had my first serious try to split it this year. The secondary emerged from the glare of the primary for about ten percent of the time (180 Mak), appearing as a dot in the halo of the primary. Best mag was about x180, and the view was slightly better with a neutral density filter which reduced the halo a bit. I've seen it better once or twice in previous years, but it was at least a split. Maybe the Moon helped, as it sometimes does when splitting a difficult double such as Sirius.

When Antares disappeared behind a roof, I looked at some of the more challenging doubles in Cygnus; both Lambda and Delta Cyg were split fairly easily, with nearby Epsilon Lyrae taking mag up to about x400, showing a stable Airy disk and diffraction pattern.

Chris

What an interesting project Stu. I expect to see it followed by "the most expensive scope that can't split the double double"!

Chris

It's a balance  isn't it? Fracs give a lovely view, but with dinner plate sized Airy disks that preclude close doubles, whereas compound scopes give a messy view, but split closer doubles and equally important, show fainter companions. I compromise and get the best of both worlds by having an ED80 alongside my 180 Mak.

Chris

I was surprised by how much it had dimmed since Saturday night when I last looked. Just about visible in the 10x50 finder against the very bright summer sky, obvious through the scope. I made a couple of attempts to take an SA100 spectrum of it without any great success, although it clearly shows a nova.

Chris

1 hour ago, Nik271 said:

I tried with my 127 SW Mak at about 11pm. Sadly the air that low was very turbulent, Antares was sparkling in all colours of the rainbow.

I checked  Izar and the Double Double and got superb clear views even at 250x, so the seeing higher up was good. I think Antares requires a vacation in middle East or thereabouts. Some dry desert air and no light pollution. We can dream

I've managed it a couple of times in the past from near Oxford Nik, but not so far this year. It needs one of those very exceptional evenings. But maybe a holiday somewhere S of 30 degrees N is a better idea than waiting.....

Chris

Just had a look with the 15x70s and SkySafari - fairly easy to spot and visibly a different colour to Epsilon Aquilae and 111 Her.

Chris

Very nice sequence - we had a few clear patches here (near Oxford), but the cloud increased as the eclipse progressed.

Chris

Lovely scope! I have the Vixen 102mm f13 version which never fails to impress.

Chris

With excellent seeing last night, both were nicely split at x90. At x67, the easier pair were certainly split but the more difficult pair only just at the point of being visibly split (180 Mak with a Baader ND filter). Without the ND filter, I can't go much below x120 to split them with a visible dark space between them.

Chris

I watched it here as it rose above a tree - quite spectacular. When there was a clear patch of sky, it was so bright I could read the lettering on the front of my latest copy of AN, and interestingly, a field of yellow buttercups in front of my house did look slightly yellow. I took a quick pic with my phone at the eyepiece using my grab 'n go ED80. Sorry for the naff quality:-

Chris

John - I wonder, did the solution above solve your problem? I too have slight movement on the azimuth axis, which isn't removed by adjusting the worm against the gear wheel - my assumption is that this is due to the gear itself moving slightly on the shaft. Clearly, I need to carry out a complete stripdown (there's a post from BomberBaz with details I believe).

Chris

In my case, it is a length of nylon cord with a 1/4 Whit bolt on one end screwed into the scope rail, with a loop at the other end around a knob on the mount. Saved my scope on one occasion....

.

Chris

Very nice detail! I think quite a lot of people do still look at this forum!

Chris

Wouldn't be without mine...... Re weight, I find there is a way with lifting them that doesn't wreck the back - essentially keep it close to the body and put the eyepiece bracket against your hip.

Chris

21 hours ago, John said:

There are a couple of interesting dark patches in the ejecta from Copernicus. Copernicus H lies in the centre of one of them. It looked like a tiny bright edged pit surrounded by a darker halo of material last night. Not sure what the other one is called. I've arrowed them on this image by Andre van den Hoeven. They both stood out well under last nights illumination. At one point they were thought to be of volcanic origin but Lunar Orbiter images have showed that at least H is definitely of impact origin:

 

 

 

 

 

The dark areas are interesting - in my image below you can see others as well, although I can't see these visually. I have always assumed (but I know very little about the subject) that they are caused by fine dust settling on a darker substrate, and that an impact removes the dust immediately round the pit.

Chris

Some brilliant views last night - best for me at x190 with a 180 Mak. Schickard was amazing, but even Copernicus was showing a lot of detail in the escarpments.

Chris

A wealth of fine detail!

Chris

Clavius last night with a 180 Mak. Good seeing generally, but with some heat plume effects from a neighbours house. 1000 out of 5000 frames, processed in AS, PS and Topaz AI. More craterlet detail than will be reproduced I imagine.

Chris

Some nice targets - all we need now are clear skies!

Chris

21 hours ago, John said:

I've tried a couple of times with my 12 inch scope but with no joy at all so far

There is no harm in trying though

Indeed not - always an interesting challenge, even for those of us with small scopes which are not capable of splitting the pair!

I noticed last night that Procyon was barely twinkling, so I got my 180 Mak out and had a look to see what it actually looked like. The seeing was excellent++, so there was a stable diffraction pattern visible even at x450, with 5 rings or so as though some celestial arachnid had been at work . As the scope cooled, there were three radial bright zones which gave artefacts on the outer diff rings which looked like secondaries and could have been mistaken for them except for the fact there were three of them and they were symmetrical at 120 degrees. These disappeared after 10 minutes leaving just one bright spot at ca. PA 270 degrees which clearly wasn't Procyon B as the PA was wrong, but presumably caused by a smear on the optics or whatever. I can see how folk with small scopes often report having seen Procyon B even when it isn't technically possible.

Chris

Imaged last night (30th March 2021, 22.30 UT) with a 180 Mak/AS1220 mono camera. Image processed in Autostackert and PS. Best 20% of 5000 frames.

Chris

Just had my 102mm Vixen objective f13 'frac out for a brief spell between clouds - brief, but glorious! As with the Scopetech above, no visible CA. I also found Bailly, I think for the first time.

Chris