Nik271

If you already own a DSLR just go for a second hand lens. There are a lot of these on the market and will be even more as photographers start to transition to mirrorless and sell their old gear. You don't need image stabilization and auto focus, manual lens design was already close to perfect decades ago. A cheap doublet fast refractor will not be able to beat an average lens in my opinion.

Well done! There is something to be said for Newtonians, quite robust, and fixable (as long as the primary mirror survives). And of course easily collimatable without expensive equipment. I'm very careful with both of my Skymax 127 and 180. The big one is quite challengeing shape and weight when lifting onto the mounting plate.

I just came back from a couple of hours of great seeing. Saturn and Jupiter were fabulous but I concentrated on Neptune. Had my highest power EP, 6mm giving x450. It got easier as the time went on, the best moments were around 10pm when I could see Triton with averted vision for long periods of time. It's on the opposite side to Neptune from the 6th magnitude star, and about 1/6 of the way out. There is another much easier 12th magnitude star further out. I'm thrilled, Triton was only discovered in 19-th century with a much bigger telescope! PS. I made a sketch of the view:

Autumn is a good time to observe the Saturn nebula, it crosses the meridian around 10pm but it's never very high from the UK: only about 27 degrees in altitude at best. I found it easily last night and at 180x it looked great, pale creamy ellipse, it does resemble Saturn viewed n a department store telescope and very bad seeing

Great result, John! I'm encouraged that Triton is doable with 130mm scope. I had a look last night at Neptune around 9:30pm but the seeing did not support higher than x200 magnification. Neptune was a tiny bluish disc, best looking at x180 but there was no sight of Triton at this magnification or at x300. I didn't try anything higher than x300. My shortest focal length EP is 6mm which gives x450, I never thought I would need more. Perhaps I should invest in a 5mm or 4mm, just for the special times of great seeing on doubles and planets. I also think Stellarium is a bit conservative on atmospheric extinction. I spotted a couple of dark barges on Jupiter and the red spot at 8:30pm just before it rotated out of view, but it was quite mediocre seeing early in the evening.

Thanks for the tip! I haven't thought about how close Triton is to Neptune, but yes with such a magnitide difference looks a tall order. I will try in any case tonight, for who knows what the weather will serve at the weekend. As Horace would say : carpe noctem! (if he was an astronomer)

These days Neptune is relatively easy to find since it is very close to the 6-th magnitude star HD221148. You will need some optical finder: step from Saturn to Jupiter and continue the same distance east to Lambda Aqr. Then look for Phi Aqr further east and continue a bit less than the distance from Lambda to Phi further east. HD221148 is one of the few 6-th magnitude stars in the field and hopefully it will be recognizable as a 'double' star with a faint bluish companion - Neptune. I had no problem finding it even in moonlight yesterday. It will look better after 10-11pm when it gets higher in altitude. If the transparency is decent tonight I will try to see Triton. I've never seen it before and at mag 13 should be just within the reach of my 7 inch Mak. Theoretically.

I just packed up for the night. The seeing is meh, waited an hour but it's not improving, even at the zenith the stars are wobbly. It's very strange because otherwise is a still and clear night. Grabbed a quick view of M2 and Neptune, but at high magnification it's a lost cause ☹️

I looked up the jet stream forecast and this is what came out: Almost all of the UK except northern Scotland should have a good stable air in the upper atmosphere

Europa was expected to emerge from behind Jupiter at 1:20am last night, so that must be it. You should not bin for planetary imaging. Binning helps with noise for DSO but planets are fairly bright so you need the maximum resolition available from your sensor. When stacking the usual considerations about star sizes dominating the choice of pixel scale not longer apply. Instead it's the focal ratio of the telescope which dictates what pixel size you need. I use the rule that for planetary imaging the focal ratio should be 4 or 5 times the pixel size in micrometers. At F10 this means that your pixels should be about 2 micrometers, i.e. much smaller than in your camera. I've never seen a F10 Mak Cass, they tend to be F/12 or F/15, even F/20. With F10 there should be a big central obstruction which kind of defeats the purpose of a Mak.

Last night I enjoyed some of the best views of Saturn and Jupiter I've had for the past 2 years. The sky was a bit hazy but it was calm and despite CO making dire predictions I set up my Skymax 180 to cool from 6pm. I started observing from 8:30pm and for the first 20 mins there were occasional heat plumes disturbing the view. Then from 9pm onwards the conditions became rock steady, and I started to see detail I've never seen before: On Saturn I could trace the Cassinig division all the way around the ring. I was really obvious, like a groove in a vinyl record. The other amazing thing was a thin darkish band next to where the ring was in front the planet. Initially I thought it was the shadow the ring itself was casting on the planet but I realized this is not possible because the Sun and Earth are both on the same side of the ring plane. I believe I was seeing the inner C ring outlined across the brighter surface of the planet. That's a first for me Saturn itself was showing several pale bands, there was a prominet large and bright one near the equator. When I moved to Jupiter I was rewarded with miltiple bands, with exquisite detail. There was a prominent dark barge above the NEB, I watched it rotate out of view by 10pm. I could see some white ovals next to the white STZ in the southern hemisphere. I called it a night by 10:30pm because I had an early start in the morning, but it was really hard getting away from the eyepiece. My consolation is that the forecast for the next few days seems very similar, so fingers crossed for more of this! PS: all observations were with 15mm EP at x180 magnification.

These are fantastic! If this is what Jupiter looks this year at 24 degrees altitude then imagine the future images for the the next several years... can't wait!

Bit depth is important mostly when there is a lot of stretching of the image, e.g. in deep sky imaging. Not so for planetary as the features are fairly bright and it's better to capture as many frames as possible. When stacking the bit depth of the final image will be increased by virtue of the added information. So yes, definitely go for the 8 bit for planetary.

Very nice! The shadow of the planet on the ring is becoming very prominent now. I agree the best of the saturn season is over - on a clear night it takes several hours after sunset for the thermals to die down sufficiently at this low elevation, by which time Saturn is over the meridian and dropping down again. Next year it will be much higher.

I got out quite early today round 5:30am and was surprised to see Orion was glorious in the south, my first view of it after April. The sky was getting light but I could see hints of M42 just with my eyes and when I looked wtih my 15x70 bins the nebula was spectacular among the many stars of the belt and sword. I've seen it so many times but never tire of it. Lower down Sirius was shining so brightly I first mistook it for an approaching airplane. Winter is coming... (in a good way!)

Svbony recenty updated their 15mm EP. The old model (red line 68 degree Fov) was definitely the weakest of their 'red' line up and in July I decided to try this new EP. It's labelled SV154 and claims to be FMC and 70 degree FoV. It retails at about £45-50 pounds on ebay and amazon, so not so cheap, but still in the budget price band for eyepieces. Mine arrived very quickly in a small box containg the EP, caps on both ends and a cleaning cloth. It is well made, all metal with rubberized twist-up eye cups. Here are some photos: The front and back lens elements are certainly coated, and I haven't taken it apart to check the inner elements. (Svbony lists this EP has 5 lenses in 4 groups.) The eye relief is a bit short at 13mm. I found that when I use it with glasses I cannot see to edge of the field stop. When I remove my glasses I get the full view to the field stop and with testing on the sun and terrestrial objects I can confirm that the field of view is indeed 70 degrees. I have used this with my Maks, which at F/12 and F/15 are not really a challenge for most EPs. Views of the moon, planets and double stars are indeed very good, sharp across 85% of the field. This is notable improvement on the old red 15mm. The light scatter/ghosting seems well controlled, I had no issue even with a full moon. There is no kidney bean effect at all (unlike the 9mm and 6mm models). Overall I'm very happy with this new EP. My only criticism is the eye relief as I tend to observe with glasses and all my other EPs allow me to use them. On the other hand the eye cup is an improvement on the flimsy rubber guards of the older model, and it does shield the external light quite well, even in sunshine when I look at the sun. Would I buy this again? Yes. At this price I would not call it a great bargain but it's good value for money. Nik

I'm not an expert but my guess is that the image of a non-point light source is the integration of the airy discs of its points. So for a small circular light source the image will have two parts: the circle itself which will be the brightest part, and a fainter ''halo'' around it from the contribution of the airy discs near the boundary. As usual, an unobstructed scope e.g. a refractor will show a fainter halo because the diffraction rings contain less energy than in obstructed scopes. This must be why refractors produce tighter images of the moons. But in all cases the diameter of the image will be larger than the apparent diameter of the moon. As an approximation I guess we have to add the apparent moon diameter to the diameter of the airy disc of the telescope. It's probably not so simple because the ''halo'' is fainter but without calculations this is the best I can think of. If we accept this then in a 4 inch telescope Ganymede looks like a 2.9'' disc while Europa is 2.2''. At say x120 magnification these will look like 5.8 arcminutes and 4.4 arcminutes, so well within the average observer ability to distinguish them as discs rather than stars and also to spot the difference in size.

A great report! Makes me sad that we are missing this wonder with the light pollution in our cities. Last week I managed a trip under very dark skies on holiday in Bulgaria and enjoyed the whole span of the Milky way: an arch across the sky, great rift and all. It was amazing. I was carrying only 10x50 binos but that was plenty, saw so much with them. My brother and his girlfriend were with me and were amazed that binoculars can show them so many stars and nebulas. They were most impressed with the Andromeda galaxy, it was obvious naked eye and looking huge in the binos. I got my perfect view of the North America nebula right at the zenith. In the cold my hands were freezing holding the binos after an hour but I didn't mind at all

I used to have the same telescope. It's not very good for planetary views, because the mirror (at least in the models made in recent times) is spherical, not parabolic. As a consquence not all of the light comes into focus, I would say beyong 70x magnification the views start to get mushy. There are two things you can do to improve planetary views: 1. Check if the scope is roughly collimated. Can you see the three mirror clips when looking through the focuser without an eyepiece. If yes, you are good.There is no center spot on the mirror, so this is the best you can do for this step. 2. Create an aperture mask: cut a circle or oval from cardboard of diameter 80-90mm and put it over the front opening. It can even be offset to miss some of the central obstruction. This way you lose some resolution but overcome the problem of spherical abberration and the views should be clearer. 80mm is still plenty of aperture to see the bands and GRS on Jupiter. Try 10mm with 2x barlow for 130x magnification. Have fun with the scope, despite its drawbacks it can still show plenty! Nik

M33 is twice the diameter of the full moon and it does not have a bright core, so it's pretty hard to spot in a telescope even in low powers. I've seen it in binoculars several times in the autumn and winter from Oxford, which is Bortle 6 and it is always tricky for me. Try it when its higher in the sky in the autumn.

PS. You mention that the planets were only at 14 degrees altitude, that makes it harder to get good seeing and focus. I have noticed great improvement in the quality of my views compared to last year when Jupiter barely reached 16 degrees and this year when its well above 20 near midnight.

I had a look at the video file and it seems that the focus is off and/or the seeing is poor. Focusing for planetary work is critical and to nail the exact focus you need in this order: 1. Good seeing 2. Big screen where you can zoom in the image to see exactly at which point it is sharpest. 3. Good focuser with slow movement. Some people install top quaility focusers on their Maks but they tend to cost a fortune. You can try the low tech clothes peg clipped to the focusing knob to give you more precise control. I have imaged planets with the Skymax 127 and a DSLR and it can produce quite good images. So keep trying!

Lovely detail! Is this a Bresser Mak or Bresser frac?

Lovely report, I enjoyed reading it! There was some good seeing here last night, perhaps not as good as what you describe. I spent a lot of time on Jupiter and Saturn, stayed at x170 magnification. Just as you I found it hard to stop, kept switching between Jupiter and Saturn every 20mins or so until it was very late. After an hour or so the movement of the moons became very noticeable. Saturn had a very 3D look with several moons visible: Titan, Rhea and Dione. On Jupiter I could see a small dark storm on the north edge of the north equatorial belt. My Skywatcher Mak has aperture of 120mm but it was showing plenty of detail. Proves that for planetary views seeing is more important than aperture. A well made scope of 4 or 5 inch aperture shows a lot when the seeing is good.

I had clear, slightly hazy skies last night and had a good look at RS Oph with 10x50bins. It seems similar brightness to the nearby HIP 87396 so magnitude 8. The colour was not showing very well perhaps because of the high haze/mist.