Nik271

I don't remember seeing this visually in my Maks (with 120 and 180mm aperture) but I've never looked for it. I checked some old images taken with the 180mm Mak last year of the Marius area and the rille shows clearly. So I seems that 180mm should resolve it at least part of the way:

Nice list of targets! I like the idea of a bike ride to an observing location. I recently assembled a lightweight rig: Manfrotto tripod, AZ5 Deluxe and the 127 Mak, total weight it about 7kgs, easy to carry in a backback. Will try it on a warmer night later in spring. M101 is more of a binocular or finderscope target, it is large and diffuse, will be very hard to spot in a 1 degree field of the Mak. Last night I was also using my 127Mak and can recommend a couple of (new for me) galaxies within reach of the Mak in Canes Venatici: M106, shows as a elongated fuzzy blob. NGC 4990 (Cocoon galaxy), just a degree west from Chara, seen with averted vision mostly. It has a dim companion at mag 11 that was invisible in Bortle 5 but may show up in a draker location.. I also tried for the Whale galaxy NGC 4631 but could not spot that one. I still think it should be doable in the Mak, just have to pick a moonless night.

This is normal it's how the dew forms on glass which is not 100% clean, the moisture attaches to the (usually invisible) traces of dust, pollen and sediment on the glass. Only worth cleaning if you can see any residue after it dries out.

A sturdy BBQ cover which has D-hooks to attach it firmly to the mount or to tent pegs in the ground. I keep my EQ5 this way outside from May to September, no issues so far. Just make sure to lift the cover on a sunny day to let any condensation dry out. In winter I try to bring it in the shed whenever I can, since the garden is perpetually damp most days and I worry about moisture getting in the optics, especially in the closed designs like Maks.

Yes, the seeing was mediocre. There were still goodies to see. I had a look at the lunar limb with my Skymax 127, there were lots of interesting features, mountains casting shadows on more mountains. My eye was drawn towards the Leibnitz range in the south: And there was this one on the edge of Mare Orientale, looked very much like a copy of the lonely mountain in the Hobbit (or Sugarloaf perhaps?) The real view was actually more impressive in the eyepiece than this simulation from NASA: (https://svs.gsfc.nasa.gov/4955)

4:30am brief session snatching an hour of observing before start of the day. I looked at Antares with my 127 Mak, but the seeing was too poor to attempt splitting it. M4 nearbly looked very disappointing, just visible at x75. I've never seen it stand out - it is both low on the horizon and in a very light polluted area of the sky for me. M19 further east was better, I guess it's both smaller, brighter and more concentrated. Lots of wide doubles in Scorpius and Ophiuchus.

I tried last night with Skymax 127 at about 9pm, the seeing was not the best but decent, I could see some faint details like Rima Prinz, but sadly no sign of Rima Sharp even when looking directly at the spot where its supposed to be. Either its too small for 5 inches aperture or the sun angle was not right. Aristarchus region looked very nice, with vallis Schroteri partially illiminated with deep shadows all round. I will try again this evening if the clouds cooperate. Sinus Roris will be fully in the sun and the elusive Rima Sharp may be easier to spot.

Has anyone observed Rima Sharp with a modest aperture (e.g. 5 inches or less)? I have tried a couple of times in what I thought is the right moon phase but the seeing was not cooperative. I've heard it's not an easy one, certainly does not get many observing reports. Tonight it should be right on the terminator, this is the simulation at 20:00 UT. It may be even more prominent a few hours later.

After a few more weeks and several clear nights of use here is an update: I managed a new moon DSO session in my Bortle 5 garden. I focused on the Ursa Major part of the sky. M81/M82 were showing nicely in the same field of view in the SVbony 15mm EP. The shapes of both galaxies were clearly defined, but not much detail of their structure was visible. I admit I have not seen anything beter in these from my garden even with a 6 inch reflector. Then Owl nebula M97: faint smudge against light polluted sky. It was much better with the OIII filter, the circular shape was obvious but no sign of the 'eyes'. Nearby the M108 was barely detectable, as was M109 lower down: from experience I know where to look and I could detect them with averted vision but they were very faint. I didn't expect anything more than that with 4 inch aperture. Then I looked at the low clusters in the south: M41, M47, M46. This is where the wide field refractors excels, they were looking lovely indeed despite being low. With OIII filter I spotted the planetary NGC 2438 in M46, had to use x90 with a 8mm Starguider for that. I recently purchased a high power 3.2mm TMB planetary EP so I tried it on Theta Aurigaue and Rigel, but the views were disaapointing. The stars were easily split but looked rather mushy with purple halo. I'm not getting this in 6mm or 4mm EPs, so perhaps this is the limit of the scope, about x180. Fair enough as I have my Maks which are more suitable for high powers. I started using the scope as a quick grab and go on a photo tripod and AZ5 deluxe. A bit wobbly in the wind but definitely light and ready for action in seconds when there is a gap in the clouds. Recently managed a bried look at the first quarter moon in a 10 minute cloud gap spell and the view was lovely. A side note: I don't like where the finder screws are located near the focuser as this is too low for me. So I glued a small finder shoe to the tube directly behind the dew shield. Perfect location for a RDF. Here is a picture.

Exit pupil is defined as the scope aperture (in mm) divided by the magnification. Another way to compute it is: focal length of your EP (in mm) divided by the focal ratio of your scope. Exit pupil is a measure how much light is reaching your eye which affects how bright the image will appear in the eyepiece. The relatonship is qudratic, so exit pupil of 2mm results in 4 times as bright image compared to 1mm exit pupil. The maximum usable exit pipul is the width of your eye pupil which is 5 to 7mm depending on age. So for example if you have F/5 Newtonian a 40mm EP will give you whopping 8mm exit pupil, too large to be captured all by your eye.

I just came back from a quick solar session with a WL filter on my Skymax 127. Seeing is OKish for about x80. AR2960 is one of the larger sunspots recently and very well placed at the moment near the centre of the disk. There is lots of detail visible in the umbra and penumbra. There is also a new group AR6965 which is rotating into view, looks quite active edge on, with bright faculae contrasting with the darker limb. Take a look if you have time and clear sky! Nik

Well done! In light polluted skies sometimes more magnification helps because it reduses the brightness of the background. I would suggest something like 2mm exit pupil. It works well in my SW Mak 127 for deep sky.

No, it's too small to make any difference. In fact cleaning the mirror and front corrector can introduce micro scratches over time which scatter the light and have worse effect than any dust or small blemishes.

Clouded here too, I think it's supposed to clear again from midnight but I have an early start tomorrow. Enjoy it if you can!

Managed to see both Rupes Cauchy and Rima Cauchy near well... crater Cauchy on the edge of sea of Tranquility. The Rupes is an easier one but the Rima is quite subtle and needs the correct illumination as today. Also there is some linear 'valley'-like feature just north of De La Rue and Strabo. Does anyone know what is it? Perhaps it is an illusion, can't seem to find it on my maps.

Yes a couple of times, on the Owl and to tease out the planetary nebula NGC 2438 in M46 a couple of weeks ago. I guess a UHC filter can be just as suitable depending on the exit pupil. Ignoring magnification you can get large exit pupil (i.e. bright image) with very low power EP in almost any scope. For example in a F7 scope the 32mm Plossl gives you massive 4.5mm exit pupil, so no problem using narrowband filters. This will work well on the large nebulae where you don't need much magnification. The advantage of a big aperture and fast scope (like e.g. 8+inch Dob) is that you can have both magnification and large exit pupil at the same time, so can zoom in small detail even with a filter and then you will see much more. Nik

Lalande 21185, one of the closest and brightest red dwarfs to us (at 8 light years away and mag 7.5). The fun part was trying to find it manually. The nearest naked eye bright stars are 46 Leo Minor and 54 UMa which are also orange, but being 10 times more distant are red giants, not red dwarfs. Then I had a look at the Alulas, managed to split the Alula Australis at x180 but Alula Borealis, Nu UMa ( another orange star) defeated my Svbony refractor.

M78 and M97 are subtle in suburban skies with a 100mm scope. As it happens I was looking at them too last night with my new Svbony 102 ED refractor and while I could spot them they were not easy. (Several years ago I spent ages trying and failing to spot M97 with a 6 inch reflector, so experience and knowing what to expect really helps.) For the Owl (M97) an OIII filter helps a lot. I did compare the views and with the filter the nebula become super easy to see. M108 is a tougher object. Since it's a galaxy filters will not help, only dark skies will make it to stand out. I could barely detect it last night.

The main consideration is matching the focal length of your scope with the pixel size on the sensor of your camera. With a Gti mount (not very precise entry level mount) something like 2-3 arcsecond per pixel sampling rate should look OK. The 72 Evostar at 420mm and the 60D at 4.3micrometers pixel size gives you about 2.1''/pixel which seems OK. You can easily image some of the big nebulae e.g. the Orion, the Veil, North America, Rosette. As for galaxies Andromeda, Triangulum, Pinwheel could be framed nicely on the large APS-C size sensor of the 60D. For the smaller galaxies and planetaries you will need longer focal length, better mount and everything will become much much more expensive. But there is plenty of fun to be had with 400mm focal length refractor and a DSLR!

The pink is probably due to the UHC filter. Try without to see if it makes a difference.

I have a 40mm plossl but instead I tend to use the 32mm because the true field of views are almost identical, just over 1 degree. If you have light polluted skies then you don't want very low magnification because the sky background becomes too bright.

I sometimes use binoculars first to familiarise myself with the area, even if they can't show me the target, and then a use my 9x50 finder to point the scope close to it. The red dots are not very good for finding stuff, if you are doing it manually a good optical finder is a must.

These are great images, Kon! The ISS moves so quickly, at this focal length you must be doing miracles with your Dob to keep it in the frame and in focus!

I was looking at M46 last night as well with 100mm refractor and at first could not see the planetary nebula. When I put my OIII filter in the 20mm Svbony EP ( 3mm exit pupil) the nebula popped out. At my low magnificatiion x35 it looked like a slightly defocused star. The transparency was very good last night in my location, I spent a lot of time scanning the low southern horizon at low magnification. I was very happy to spot the open cluster NGC 2362 arount Tau CMa. The faint stars surrounding Tau seemed to wink in and out of existence with averted vision. If there is a 'ghost' cluster this is it!

With 80mm the airy disc diameter is about 1.7 arcseconds in green light (a bit larger in red and a bit smaller in blue). So at best you can see an elongation, as this simulation suggests: Well done for spotting it with your 80ED! My seeing was relatively poor and I couldn't use more than x120 in my 102mm ED last night. The smallest aperture I've seen the third close component of Tegmine is my 127 Mak at about x250 and it was not a clean split. By contrast my 180 Mak makes it almost easy on a good night but that is more than twice the aperture.