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By Cosmic Geoff
Here is a EEVA-style image of Neptune and apparently its largest moon, Triton. I had been trying to image planetary nebulae before aiming the gear at Neptune, and noticed a faint smudge below the severely over-exposed planet. It was possibly easier to see at the time than on the processed image attached (between planet and arrow). It seems to match the position given by Sky & telescope's Triton Tracker.
At around mag 13.5, Triton would normally be beyond the reach of a C8 used visually even in ideal conditions.
Image is inverted, taken 12Aug at 22.40 UT. CPC800,ASI224MC, flip mirror. Gibbous moon.
By Cosmic Geoff
An image of Jupiter taken late evening, 27 June. Not as good as some other people's efforts, but one of my best Jupiter images this year. The planet was low (around 15 deg) and the seeing was not great. CPC800, ASI224MC, ADC, captured in Sharpcap, processed in Registax6.
Best 20% of 5000 frames IIRC. One of the images here is a random raw frame, to show what I had to work with. Io should be visible on left in the processed image.
By Cosmic Geoff
An image of Jupiter taken early morning, 16 June. Not as good as some other people's efforts, but the planet was low (around 15 deg) and the seeing was not great. CPC800, ASI224MC, ADC, captured in Sharpcap, processed in Registax6.
Best 15% of 7000 frames IIRC. One of the images here is a random raw frame, to show what I had to work with. Ganymede should be visible on left in the processed image. GRS coming into view on left.
It is not often in the UK that we have a bank holiday weekend, a new moon and a clear sky at the same time. Last night was one of those rare occasions! The forecast (Clear Outside) was not very definitive about the cloud cover, but from looking at the satellite images and from experience, I thought this could be a magnificent sky as we were on the backside of the last weather front.
So, I thought – let’s give it a go, we could be rewarded.
By 9pm the car was packed with the C8 and my trusty Vixen SP-DX. A quick check on my friend Steve, and yes, he was up for it, too. Steve is a beginner, so I offered to show him some of the objects I am familiar with and should give a decent view under good conditions. I also wanted to see some of the fainter galaxies which populate the spring skies.
The spot we were planning on using is in Southern Cambridgeshire – and compared to light polluted London and St Albans, this looks like “Deep-Sky-Country”, although it actually isn’t perfect. It’s the improvement from the home conditions that count!
On the way, I cranked up the aircon to maximum (lowest temp) to pre-cool the scope. This was going to be a chilly night…
Arrived at the spot just after 10pm, Steve parked up five minutes later. Thankfully the wind that had battered the South East the whole day had eased off and the remnants of daytime clouds soon hurried to disappear. I spent some time building up the scope and polar aligning while the last bits of twilight disappeared.
The sky was now fully dark and really quite impressive considering how close to London this place still is. To the South the capital’s light dome stretched to about 20° above the horizon. Cambridge cast its lights in the North-East although to a much lesser degree.
The spring constellations were up to the South with Leo having passed the meridian and the plough right above us in the zenith. We started the evening with a simple target to warm up – M3. A delightful sparkle of stars filled the eyepiece. With the 15mm LV (133x) the core was starting to be resolved - the telescope was not completely cooled down yet, but this was indeed a good starter to the night indeed.
Next, we changed direction and pointed at M51, which clearly showed the two galaxy nuclei and the surrounding disc of haziness with direct vision. No spiral structure visible (but that wasn’t really expected with 8” anyway). The pair was nicely framed in the 30mm NLVW (68x) with a foreground star in NGC5194 clearly discernible.
As spring is galaxy season we pushed the scope over to Denebola in Leo to go hunting for members of the Virgo cluster.
We started with M98, which was a fuzzy faint blob and a bit disappointing. Next object was M99, which was much more pronounced although without any detail in the 30mm. Over to M84 and the starting point of Markarian’s chain. Using the 40mm Celestron Axiom eyepiece (70° afov) four galaxies were immediately visible. There was a bright one in the bottom of the view (M84), with a slightly bigger one in the centre (M86) and a pair of two distinct but faint galaxies to the top (NGC4435/38). Slewing along a bit further, NGC4458 became visible. An incredible sight, especially if you imagine how many millions of light years these are away from us and how big these objects are!
We did not follow the rest of the chain (have to revisit this again!), but instead decided to look at something brighter.
M81/82 were right over head and simply amazing. Directly viewed, both fit into the eyepiece at 50x magnification (40mm Axiom). M81 clearly an elongated, lens shaped disc. M82 showed as a thick streak of light. Ramping up the magnification to 133x (15mm LV), it revealed its knotted structure with direct vision! It has been a long time since I had seen M82 this clearly. The sky was indeed rather good!
To get a bit of variety, I moved the scope to the owl (M97). In went the Lumicon OIII Filter. In the 15mm LV, the sky background turned into an inky black with the stars taking on a slightly reddish colour. The nebula stood out like it was cut out of cardboard! While gazing at it for a little while longer, we were able to see some texture inside the “disc” of the nebula – hints of the owl eyes.
As the filter was in, we decided look at another planetary – M57 the ring in Lyra. About 50° above the horizon, a clear ring shape with a dark interior was visible against a black sky (thanks to the filter) - beautifully defined and clear! Next up was M13, the great Hercules globular cluster and it was sparkling with the lights of millions of suns. An extremely contrasty view, resolved into the core…
Suddenly we realised some clouds had started to appear, coming in from the North and beginning to cover parts of the North-Eastern sky. So we changed direction (yet again), to look at more galaxies. The whale (NGC4631) was faint, but clearly defined in shape, really resembling a maritime. Unfortunately, we did not look out for NGC 4627, the whale’s companion.
NGC4656 – the hockey stick, was faintly visible with averted vision, but no clear shape discernible.
NGC4565 – the Needle was starting to get blocked out by a thin layer of high clouds at around 11.45pm. A slightly disappointing sight. By this time, the finder had already dewed up and the first patched of haze were forming on the corrector plate of the C8.
The sky was now also covered over more and more, so we decided to end the evening at this point.
We packed everything back into the car in about 20mins and drove off at around 12.15. While driving I noticed my feet were actually deep frozen already! The car showed a temperature of just 4°C, no wonder it felt chilly. Thankfully the wind had not picked up all night. Overall a wonderful session with many old favourites and some new additions as well as some targets left over for the next galaxy season. Have to revisit Markarian again and scan the full extent, also missed the black eye and sombrero galaxies this time. Let’s hope for more clear skies soon!
Hey guys. Thought about starting this thread. I feel like we all should inform eachother and newer members alike about the magngifications that can be achieved on planets,that provide the best sharpness/size ratio,depending on the scope and seeing. After this thread has grown a bit, i feel like this should be pinned,as to provide a little guide to newer members that are not experienced with planetary observing,as many will be fooled with the typical 50x per inch of aperture and get disappointed when they find that that image will be dim and blurry.
For my 8” F/6 Sky-Watcher Dob
For Saturn i like to use 150x in medium seeing and if i want something a bit bigger , switch to 240x ,which will give me a bigger,but blurrier image.iBut In good seeing, i found that 240x was very usable.When we have perfect conditions, i m certainly trying 300x.
Mars, isnt very big in the sky right now,so even at high magnifications like 300x it still appears as a small orange dot. For observing mars,I suggest waiting for it to reach opposition.It benifits hugely from it! However,this happens once every 2 years....But 5ere are other planets to keep you occupied until then, such as jupiter,saturn and Venus.
For Venus, i use 50-100-120 depending on its phase.
For Jupiter, i like to use 150x, as it provides a very sharp image,with key features of the planet such as bands being very detailed.Waiting on my 6mm UWA Skywatcher to bring it to 200 and see how that plays out. Be careful! Don’t magnify jupiter too much, as it will loose much of its features and sharpness.
Neptune and Uranus: These two will not impress, but are certainly have a nice colour to them. Even ar high magnifications, such as 300x and 400x, they will look like small discs with color in them.Uranus will look be colored green and Neptune a fainter blue.
Mercury About mercury...Havent gotten the chance to observe it ,so the guys will have to inform you about that?
Feel free to give your own opinions as to give members a wider source of information to help them observe better !
Cheers and clear skies.