chiltonstar

15 minutes ago, cloudsweeper said:

Saturday, 4.40pm, 8SE ready. Jupiter low, west of south – Galilean moons nicely lined up on the same side.  Aligned on him, and GoTo put me very close for all targets.

I wanted to try for some 1.3” doubles, and went for D20 Aql, but going up to x254 didn’t crack it, and the star images were getting very fuzzy.  This seems to be an issue with the SCT.  The Dob is better (managed a 1” split last month), but fracs certainly win in this regard.

 

Doug.

Collimation? The 8SE should surely manage 1.3 arcsec.

Chris

Good to see someone has seen the night sky recently.......... nowt but permacloud here.

Chris

If you look at the spectrum  of an LED streetlight,  there is an intense blue band (loads of scatter) but less emission towards the green, so a filter passing just this wavelength should improve signal to background ratio.

Chris

The 180 Mak deserves its reputation for doubles and planetary views, but no scope can beat the weather and poor seeing!

Last week, I had one good night where the E and F stars were visible in the Trapezium, several 1 arcsec pairs easily split in Orion, and even Sirius just about starting to split as it rose in the sky, but tiredness set in at that point. Good nights are few and far between!

Chris

Some very nice craterlet detail there.....

Chris

A very nice Uranus!

Chris

I used to subscribe in the '80s and '90s, and found it excellent. Since then, I've only bought the December edition with the Skygazers' Almanac most years; one or two good articles usually, but not much comparison with AN. So it looks as though I will have to look for a copy of the Almanac online somewhere from now on....

Chris

Very nice indeed!

Chris

Lovely looking scope! When the Weather Gods permit, the first light report will be eagerly awaited. Contrast on eg Mars would be interesting.....

Chris

1 hour ago, davidc135 said:

Above is a sketch taken 2 days ago with an 8'' sct in so-so seeing. Mag x160. The sw (proceeding) finger was prominent. Interesting to follow any changes to come.   David

I wonder if other changes are underway? I had a good look at Mars later on last night after the storm area had cleared the disk*, and I had the distinct impression that the overall colour of Mars was slightly different than it was say a couple of weeks ago, more a sort of peachy tint rather than the yellow-brown colour near opposition. It would be interesting to know what sort of colour shift you get if dust levels build up in the atmosphere?

Chris

*180 Mak at x180 to x250. Near excellent seeing.

Yes, clearly visible. Thanks for the frac view John.

Chris

I tried a little earlier with my 102mm f13 frac, and thought I could see something but the seeing was too poor to be sure.

Chris

18 hours ago, RobertI said:

The blog is a fascinating read, there are some really dedicated people doing some great work there. I never knew there was so much happening on Mars! 

Quite tempts me to join the BAA! I've been thinking about it for some time.

Cris

I haven't spotted them yet, but on the other hand, I haven't spotted the LGMs (little green microbes) yet on Venus.

Chris

What an interesting list! My 180 Mak will reach in theory, and often in practice, 0.7 arcsec splits although it does require excellent seeing - usually warm summer evenings when the ground and air temperatures are similar and there are no thermals. How is the seeing and viewing conditions in your location Armand? The UK suffers from poor wet weather, with many Atlantic storms which means the number of evenings we can observe is often quite limited.

Chris

23 minutes ago, ollypenrice said:

I've never managed it naked eye even from here. In the next life I'd like good eyesight!

Olly

It has been when M33 is nearly at the zenith, after rain. My location is small village, with low LP to the E, S and SW, but I'm sure some evil developer will soon sort that for me.

My eyesight is no longer what it was, particularly when I'm tired, but my grandson could see it easily - he is 9 though. He could also spot cargo vehicles next to the ISS when I could only see a white dot.

Chris

I think Olly is right - it pops out as you rock the scope even with my medium aperture (180 Mak). On exceptional nights, I've seen it by eye without scope or bins, and on those occasions it was clearly a galaxy with some structure I was looking at through the scope. 

Chris

I've not looked up a scope with a binoviewer so I can't comment from a practical point of view, although it does seem illogical to strive for more aperture to see fainter objects, and to then halve image brightness by splitting the light beam into two (worse if there are losses at the optical surfaces). I did have a peer up a binocular newtonian arrangement at a conference in the US, which was a pair of 8" newtonians side by side - that was very impressive, although I didn't look at high mag where I suppose any collimation errors between the two tubes would show up. That did cancel the spider artefacts to some extent as the two spiders were set at a slight angle to each other.

I can see good theoretical reasons why binoviewing would cancel out any issues caused after the beam was split (eyepieces, eyes) but I would have imagined that anything before the spit such as seeing the spider artefact would be additive, as both eyes were seeing it.

Must have a look some time though.

Chris

10 hours ago, Stu said:

 

I shall continue to use the binoviewers for Mars, they certainly improved the view, and also reduced the visibility of the diffraction spikes which was a nice surprise.

 

Why was this, I wonder? The binoviewer splits a single beam, so why should it reduce image artefacts?

Chris

I copy pages from CDSA and ring doubles of interest on the copy, which is reasonably visible. I hadn't realised that SkySafari could load the CDSA list and highlight them - that sounds an excellent idea.

Recording the data and observations in the dark/cold/wet is usually a problem! I suppose if I was even more of a "compulsive list maker" I would use my phone or a digital voice recorder to record observations and then transfer them to a spreadsheet in the warm & dry. Being seen talking to a telescope might get the men in white coats sent round though....

Chris

Similar to other folks - a truly dark sky in a stunning place. For me this was camping near the foothills of Kilimanjaro on a holiday of a lifetime (nearly free, my wife and I went along as translators). As well as the sky, the sound effects added by some of the wildlife were quite impressive!

Chris

...and I thought my 4" f13 was a monster! Clearly after looking at some of these pics of gorgeous big 'fracs, mine is just a babe and has a long way to grow!

Chris

6 minutes ago, Captain Magenta said:

I have a Skywatcher blue-tube 12" newt, and I'd ordered myself a new 1/10 wave 300mm f/5.3 primary from Orion Optics to upgrade it. When it finally arrived the previous weekend (scratched actually, but that's a different story) I simply swapped the mirrors over, slightly different f-numbers notwithstanding, to take some photos to establish its exact focal length prior to me ordering a new longer carbon tube for it. Obviously I had to look at Mars too and I'm glad I did! Extraordinary view, NASA-like describes it well, I thought I was looking at a Mars atlas at moments, it was freezing into amazing clarity.

I hope your motor or mount not damaged?

M

No, happens if I swing the mount to the SW and forget to do the "flip". I purposely mounted the motor so it would come off if bashed.

The scope sounds fantastic. I sometimes entertain the idea of bigger scope but old age kicks in, and I reflect on what it would do to my back.

Chris

2 hours ago, Captain Magenta said:

Great image. Incidentally your image corresponds almost exactly with the eyepiece view I had using my new mirror early last week. Far and away the best view I've had of Mars.

M

Thanks. What is the mirror size and spec?

The night before I took the image above, I was looking visually - the view was near-NASA like, with excellent seeing, but unfortunately when I got the EQ mount out, I crashed the scope into the RA motor and had to remount the motor the next day.

Chris

3 minutes ago, Stu said:

Excellent image Chris. Interesting that Hellas doesn’t show up as brightly as in the simulation. Visually I’ve seen it, but again, not as obvious as implied on the Mars Mapper.

If I remember correctly, the BAA Mars mapper uses images from Damian compiled to make a full sphere. I suppose the relative brightness of Hellas may depend on where Hellas was when it was imaged?

Chris