Nik271

This morning I had a quick look at the Moon and learned something interesting. I was using too much power (just forgot the eyepiece from the previous observation of Mars) So 180 Skymax at x300 -the Moon was wavering with the morning turbulence but still the features near the terminator were clear and contrasty. I love the Mak. First I observed the Schroteri valley: close to the terminator presenting a good view with its zig-zaggin shape near Aristarchus and Herodotus crates, one of my favourite areas of the Moon. Next I looked at Marius, trying to spot the Marius 'hills' and as the scenery drifted west I noticed a oval bright patch to the southwest of Marius. It was quite bright and had a 'wavy' boundary. I made a note to check it up. Thankfully there is the free online LROC map: https://quickmap.lroc.asu.edu/ which has all kinds of information overlays. It turned out this oval is called Reiner Gamma. Its not a crater but a 'lunar swirl'. Wikipedia has a nice article on these: https://en.wikipedia.org/wiki/Lunar_swirls You definitely don't need x300 to see it, just about any telescope will show it, probably even at x50. Apparently their bright albedo is due to magnetic anomalies which bend the solar wind away so the rock is not as weathered and stays 'young'. The source of the anomalies is still a mystery. Interesting stuff! I hope we go back there and investigate some day soon. Clear skies! Nikolay

That's a great image, Adam! Certainly much better than my first one Saturn is quite low and this year (and next) so can't really expect much better than this. Here is how to choose how many frames to stack: when you analyse the frames in Autostakkert look at the graph which lists them ordered by quality. I personally aim to stack frames which are in the top 75% in quality, this usually means I only stack between 10% and 25% of the frames, depending on the seeing conditions. Pipp also has quality sorting option which is very helpful. I usually choose to discard 30% of the lowest quality according to Pipp and then load Autostakkert. So its important to shoot many frames, 3-4 thousand at a minimum. Also Saturn rotates, slower than Jupiter and stacking will compensate for it, but there is a limit how far you can go without derotation. I personally would try to asqure all frames in a 5-6 minute interval at most, since I'm not using derotation. Clear skies! Nikolay

Thanks, John, the sketch is very helpful! I had no problem seeing the further stars, so it's really about seeing through the glare of the primary. Knowing where to look makes it much easier.

The weather forecast was for clear skies this morning and on a whim I decided I will try for the elusive Sirius B since these years the separation is as large as possible: almost 11''. Sirius transits the meridian at 6:30am when its 21 degrees high - as good as it gets from here. I went outside at 6am and there were some high clouds but the southern sky was clear. Unfortunately Sirius itself was twinkling and I knew it was going to be a mission impossible. I used 9mm with my Skymax 180 giving 300x magnification. As I feared Sirius was a blob, dancing in rainbow colours and no sign of the Pup. I tried averted vision, moving Sirius just outside the FOV but nothing helped. Oh well... I wanted to make sure its not the optics, so I pointed at Rigel and saw the companion easily: a pale blue dot southwest of the primary, well separated, I think 10''. The companion of Rigel is magnitude 7, while Sirius B is 8.4 and lower in altitude so it's bound to be much harder. Well, I was up at 6:30am on a Sunday so decided to have some fun anyway and aimed for Alnitak. Last winter I tried repeatedly to split it with a Skymax 127 but never could. Today it was 'almost' easy: I had to wait for moments of good seeing and then it was visible as a yellow dot very close and south of the primary. Nice! It was getting light but the moon was almost overhead and looked clear. Using 300x I could clearly see the bow of Sinus Iridum and also some shadows on the floor or Aristarchus and Vallis Schroteri next to it. Definitely worth getting up early on Sunday! Further south the crater Gassendi was very nice with its central peaks. I could see a long line to the east it. When I came back I checked the Lunar Orbiter map to identify it - it was Rimae Mersennius. So I didn't see the Pup but still I had a good observing session. Very happy. Obviously have to try harder for the Pup.... Clear skies! Nikolay

Congratulations, John! It's amazing to see such small objects so far away. Sadly they are beyond the ability of my scope in light polluted skies. Titania and Oberon both have about 700-800km radius, by comparison with most of the other visible gas giants moons they are tiny. (Rhea, Tethys and Dione are a bit smaller but of course much closer, brighter and easier to see.) I think if you can see Phobos or Deimos that will be an amazing feat: a pair of rocks just about 10-20km wide from 60 million km away! Nikolay

Fantastic image! Thanks for the description, it's very helpful to know what is seen.

Very nice! Mars was looking good for me too just after midnight last night. With a 180mm Mak at x300 I could spot a bright band to the east and south of Mare Cimmerium, I think it was Hesperia and Eridania. I left the scope under a towel for some winter stars observing in the morning but the dew formed the moment I opened the front cover. These Maks are dew magnets. Lets hope we get some good seeing in the next few days! Forecast looks promising ... 🙏 Nikolay

This is my best effort so far: Mak Skymax180, no barlow, taken with Canon 250D. The seeing was quite good around 1am when I took about 6000 frames in a 4min video, then Pipp , AS3! and gentle sharpening. It is very close to what I can see in the eyepiece. I'm pleased that I can spot Sinus Gomer just about visible in the image. Not a chance for that visually. Clear skies!

Hi Myles, That's a great image! The raw data will always beat the compressed, and if the object is lower than 30 degree altitude then ADC will help tho counter the atmospheric dispersion. You can do without ADC and align the red and blue channels manually in Registax but probably will lose some sharpness. However I've found that all of the above have much smaller effect than the seeing, well collimated optics and precise focus. Clear skies! Nikolay

Great idea! I believe with this scope even the liveview feed from your camera will be bright enough to see colour. I recently saw this video of a guy comparing 12inch with 16 inch dobs. The Dumbbell nebula was bright and green in the video feed:

Lovely image! I prefer the smaller one. I still image with a DSLR so planetary cameras are not in my expertise. One thing I've read is that it's better to acquire more images at the price of lower bitrate/compression because stacking compensates for that. But I'm not an expert, perhaps other can give a more informed opinion.

Thanks! Let's hope we get some good seeing for the opposition. By the way this web page shows what Mars features are visible at any given time: http://www.nightskies.net/mars/mars.html# I found it more useful than the standard Mars maps. Some people also use SkySafari, but I haven't tried it myself. Nikolay

Nice report, Vin! I was observing around 2-3am this morning and I agree with you: the seeing was excellent despite the clouds and Mars was superb. In fact this was the best view I had so far. I managed to push to x300 with a Skymax180, image was getting a bit soft but in moments of clarity Mars was like looking at it from orbit. I grabbed my camera and took some pics. The overexposed image below is pretty close to my view in the eyepiece with neodymium filter. I think your identification is correct. In my view from 3am Syrtis Major was on the limb and Sinus Sabaeus in the centre. Sadly the weather forecast for the rest of the week does not look promising here Nikolay

Impressive image, so many of the rings are visible, and even the Encke gap. Wow and even the polar hexagon!

>And does Barlow quality have an effect? I have Celestron barlow - looks like this : https://www.aliexpress.com/item/32728812306.html A Barlow will have a small effect on the image but I think in your case the collimation is the real issue. In a fast scope like your F5 even a small deviation from the ideal alignment of the light path will be noticeable at higher magnification. I suspect that there may be a little flex in the tube which is the downside to such a lightweight portable scope. Ultimately if you want high powered views and cannot fix the collimation then another scope is a solution. A Skymax 127 is a very capable scope (I have one) and its maximum magnification is about 200x, for some objects you can even go to 250x but the views become soft. They have good reputation and normally will not need any collimation. The widest view you can get from them is just over 1 degrees which is not bad. For wide angle views of extended DSO the Heritage will be better. Just beware of the slippery path to bigger scopes: eventually I decided I needed even more resolution and got the Skymax 180. Now this is NOT a grab-and-go scope

The aperture of your telescope is more then adequate for good views, actually a 127 Skymax is smaller. Granted a Mak has a very long focal length but if your telescope is well collimated you can get the same results with, say a 3mm eyepiece or for more comfortable view 3x Barlow and 10mm EP. Jupiter does not admit very high magnification, I would say about 170x for Jupiter and say 240x for Mars should be doable.. If your telescope is well collimated its aperture and atmospheric seeing are the determining factors of image resolution, not the particular design. My advice is keep the money and invest it in a good eyepiece.

Nice sketch, John! Indeed the secondary was almost opposite the drift direction and was just next to the first diffraction ring. There were long moments when I can see it separated from the airy disc, a tiny yellow-white dot. I must have hit some clear period in the seeing in the early night yesterday. It's so hard to predict when it's going to be good.

PS: I stand corrected: the Explorer 130ps has a fixed main mirror and not collimatable. What a shame! But maybe you can adjust the secondary? You will need to do this in daylight, so you can use a cheshire collimating piece or and artificial star. I can't believe they are selling a 130mm Newtonian with a fixed mirror! But then Celestron are selling Astromaster 130 with a spherical mirror at F5 so everything is possible...

Collimation is always checked in the center of the field of view. Yours is definitely off. A collimation cap on its own is not enough to verify it, in fact the star test you've performed is the best. And yes collimation is best checked at highest power. For 130mm mirror 162 seems reasonable, a well adjusted scope should easily handle that. I'll be very surprised if the 130ps is not collimatable, Skywatcher is a very reliable brand. Do you have 6 screw at the back of the main mirror? In some scopes they are hidden behind a thin removable panel. The small screws are locking, and the big screws adjust the tilt of the mirror.

smallscope? smallscope!!!! Outrageous, the big Mak is not small but perfectly proportioned 🙂 (nice image btw)

Hi, I just want to share my excitement from last evening. It was very still and a bit misty, which to me indicated that the seeing may be good. And I was not mistaken! I had put my Skymax 180 out of the shed and by 8pm was ready to go. I started with Jupiter because it was as high as it gets and was treated to a decent view at about 150x with the GRS clearly visible and even some other 'wrinkles' in the bands just on the edge of visibility. With Jupiter going down below a roof I moved to Saturn. Even better: the Cassini division was easy to see and I could trace it around most of the ring. Some banding of the planet was visible and the shadow it cast on the ring. I was pleased to spot Rhea between Saturn and Titan and I spent some time trying to spot other moons but couldn't. I have only seen Thetys before. The good seeing reminded me of unfinished business: Zeta Herculis. I tried for it in June but never got a change with the weather. Tonight was the time. Zeta Herc was easy to find, the second brightest in Hercules and it was still at 50degree altitude. I switched to a 6mm eyepiece giving 450x hoping for luck and there it was: a small yellowish dot just on the edge of the first diffraction ring of the primary! Wow! The position was East and slightly South. I spent 15 mins looking and the dot came and went around the shapeshifting diffraction ring. Gradually it got worse, perhaps the star lost altitude or the seeing deteriorated. This morning I checked with stelle doppie and it gives separation of 1.36'' at 111degrees https://www.stelledoppie.it/index2.php?iddoppia=67135 which fits with my observation 🙂 This double system is 35 light years away with a period of 34 years and semi-major axis of just 15AU. I'm thrilled to be able to see something at these distances! The separation will grow to about 1.5'' over the next 5 years. Since I was in Hercules I had a quick look at M13 (with 15mm) but it was not the best view I've had, I guess it was not yet fully dark. I had some time to kill waiting for Mars to show up so I took a look at the Ring nebula in Lyra. It is always good in my scopes. I even tried 6mm at 450x. The ring filled the view and I could spot irregular glowing bits around the edge. I tried to see the central star but no luck. Well you can only ask for so much in a single session. At 10pm Mars was poking over the fence so I looked at it with 9mm (300x) and a neodymium filter to cut the glare. It was still low in the sky and dancing a bit but I can see the polar cap, Syrtis Major next to the west limb and Sinus Sabbaeus very prominent in the centre. My eyes were getting tired and dew was settling heavily on the Mak - time to call it a night. One of the best I've had under the stars 🙂 Thanks for reading and clear skies!

Hehe, Peter, I was imagining this Dob in a back garden... until I looked up your location web site and checked the equipment photos. Wonderful collection! And excellent outreach work you are doing over there! Nikolay

Light pollution is also my reason to go for long focal length scopes and concentrate on solar system stuff and double stars. My personal gear path was: Astromaster 130 EQ, then Skymax 127 and now I'm using a Skymax 180 which stays cool in a shed in the garden. Also don't forget the planetary nebulae, some of the small ones are quite resistant to light pollution. Clear skies!

A strong red filter is a good one for Mars. One problem with wide aperture scopes is that they make the planets super bright. I have the same issue with Jupiter sometimes. People also recommend Baader Neodymium filter for Mars but in your case I don't think it will cut out enough of the light. Can try a Moon ND filter, something moderate say 20% light transmission.

Dear Victor, I have a Skymax 127 and have used it extensively for more than a year on an EQ2-3. I never found cooldown time a problem: of course it depends on the difference of starting temperature, in my case the scope was ready within 20 mins and this is only if you need its maximal magnification (about 250x), if you observe at 100x before that, no problem. Excellent planetary and moon scope but I've observed a lot of galaxies and planetary nebulae with it. It is small (3kg I believe) , comes with a bag and easy to take with you anywhere. Nikolay