michael.h.f.wilkinson

Astronomy (especially visual) has never been more affordable. Small but capable Dobsonians are available at modest cost. I also see interest from a huge variety of people from all sorts of backgrounds in the open days of our observatory

Made the exact same swap

Or the 12 and 17 mm ES 92 deg

Partly secondary obstruction, which is almost always smaller in a Newton. My old 6"F/8 with a very small secondary and 1/10th lambda mirror was a real planet killer. Not so much grab and go. The figure of the mirror makes a big difference too. The EdgeHD may have the better mirror than a run of the mill C8. When imaging you can boost contrast, of course, which negates much of the effect of a larger secondary. I would love to have (space for) an 8"F/8 Newton, it would almost certainly beat my SCT, but it would definitely not be grab and go

The 8se doesn't have the right mount for DSO imaging. I use a Meade SN6 6" F/5 Schmidt-Newton which works nicely. I am also trying to get a Starizona Night Owl 0.4x reducer for my GP-C8 (C8 on Vixen Great Polaris mount). That would work well with my ASI183MM-Pro.

I think the C9.25 would be a bit long in terms of focal length, even with the 0.63x reducer. Outstanding for planets, however.

A C8 is very grab and go especially if stored in a cool garage so you don't have cool-down time. It outstrips the performance of my excellent little APM 80mm triplet on planets.

Here is my APM 80mm F/6 triplet on Mini-Giro mount, in tandem with the Coronado SolarMax-II 60DS

The only scope I can think of that might have roughly the same focal length, at a bigger aperture, with excellent colour correction, coming close to that price is the Explore Scientific MN-152 f/4.8. It does need cool-down and collimation, but if it is anything like my Meade SN-6 6" F/5 Schmidt-Newton, that is a breeze. I really love that Meade scope for wide-field views my SCT cannot manage, or for imaging smaller DSOs

Welcome to SGL! Plenty of members in the EU, including many in France. It can be fun meeting up with others on holidays, I have found

In late August 2021 I ordered a powerful gaming MSI GS66 laptop (i7, 32 GB RAM, nVidia RTX 3070) from Alternate.nl, partly as a powerful image processing machine, but primarily for my son's studies to run CAD/CAM software (and of course his gaming). The machine had an annoying habit of freezing, not with the more usual BSOD, but simply seizing up, responding only to the power switch. This happened with increasing frequency, up to three or four times an afternoon or evening. We tried installing new drivers, clean windows install, updating all software we could think of, adding an external cooler, as it seemed to be running hotter than my ASUS i9 , all to no avail. On November 13, we called the supplier, who said we should return the machine for repairs to MSI. Fair enough. MSI replaced the motherboard, according to the information they supplied us upon its return, so my son happily installed all the software (we had wiped the machine clean before returning it), and set off running some stuff. Two hours later he reported the machine had frozen 3 times in exactly the same way. I phoned the supplier reporting the problem, stating we had no confidence in this machine any more. We wanted either our money back, or replacement by a similar ASUS machine they had in stock. They stated that wasn't possible, they first wanted to have their technicians check the machine out. After a check we would decide what the next option was. The machine was returned to the supplier December 20. January 10 I enquired about the status, and they said they had sent it to MSI, which was not what we had agreed upon. A week later, my son still had to use a rather ancient laptop for his studies. I decided to demand a refund. They refused, and said it was impossible, and that the machine had been repaired and would be with us shortly. I stated that this was not what we had agreed upon in December, and questioned their assertion they did not have a technical department to carry out repairs. Previously they had promised to have their own technicians look at the machine, and then later they state there is no technical department. I reiterated my demand to cancel the purchase yesterday, and gave them 2 weeks to send a refund. No answer for almost two days. I bought my son a different machine (same ASUS beast I have: i9, 32GB RAM, nVidia RTX 3070) so he can work properly. This arrived yesterday, and with all the software installed hasn't once frozen. Yesterday evening they sent an email stating the machine will be arriving today. I replied immediately that they had apparently failed to read my previous email. This morning I get a reply that they cannot cancel the purchase and send a refund, and that a machine freezing repeatedly isn't a sufficient reason to cancel the purchase. I have let them know that a machine freezing repeatedly makes it unfit for purpose. I will seek legal advice on what to do when the machine arrives. Out of the roughly 4 months and 3 weeks we have been owner of this machine, we have actually had it in the house for only half that time. In that same time my ASUS machine worked essentially flawlessly, with just two crashes (BSOD style) in several months of use. Needless to say I do not think I will be using their services again.

I cannot directly compare them, as I haven't used either of them (yet). What I do know is that the CGEM is a much heavier beast than the AVX. The latter is more in the Vixen Great Polaris or Sky-Watcher EQ-5 range, whereas the CGEM is heavier than the Vixen GP-DX mount. Its payload is close to the Sky-Watcher EQ-6. It depends very much on your needs (portability vs payload in particular) which is best for you.

Addition, I would say. I really like the GP-DX. I am thinking of setting up the GP-DX on a permanent setup at the Dark Sky Park in Lauwersoog, next to the pod of the Kapteyn Astronomical Institute. I have to get permission for that, but I think I can manage that.

Second installment of the Celestron CGEM mount Now all that is needed are the counterweight and the handcontroller

Another item arrived, the first of three parcels containing a second-hand Celestron CGEM mount: The tripod has arrived! Fingers crossed the rest comes tomorrow

Just got a second-hand Losmandy style dovetail plate for the Meade SN6 6" F/5 Schmidt-Newton. Should provide a better connection to the Vixen GP-DX mount

Congrats on getting those Helios LightQuest bins. I have the more modest 16x80, which I can hand-hold, but are also better on my home-made P-mount. Your big guns would require a beefier one, I would think.

Well done, Chris! Looking forward to the next 10,000

All lectures are online, labs are open, and I can go to my office.

This year has not been my best year for DSO imaging, but nonetheless I got a few decent shots Horse-head and Flame, combining data from January and February with some older data. Canon EOS 550D with APM 80mmF/6 with 0.8x reducer, partly shot with Optolong L-eNhance and L-eXtreme filters, partly just CLS-CCD Rosette, also a combination of data from January and February. Canon EOS 550D with APM 80mmF/6 with 0.8x reducer California Nebula. ASI183MM-Pro, Astronomik 12 nm H-alpha filter, and Canon 200 mm F/2.8 L lens Flaming Star in HOO palette, using the ASI183MM-Pro behind the Sigma 50-100 mm F/1.8 zoom Hardest target to date: the Spaghetti Nebula. This is the result of 4 hours and 48 minutes on the Spaghetti Nebula, using my Sigma 50-100 mm F/1.8 zoom at full aperture and 100 mm, with the ASI183MM-Pro, and Baader F/2 H-alpha filter. Flaming star an environs in Ha-RGB this time. I grabbed 2 h 40 minutes worth of RGB subs using the ASI183MC rather than the ASI183MM-Pro behind the Sigma 50-100 mm F/1.8 zoom M78, Meade SN6 6" F/5 Schmidt-Newton, and ASI183MC (non-cooled) camera, a total of 5h 15 minutes NGC 3718, NGC 3729, and Hickson 56, using my Meade SN-6 6" F/5 Schmidt-Newton and ASI183MM-Pro and ZWO 8-position EFW, using L (2.5 h), R, G, and B, 30minutes each, 2x2 binned. Really need more data on this target One Jellyfish (just a few hours of data). ASI182MM-Pro with APM 80 mm F/6 and 0.8x reducer. Baader H-alpha and O-III filters. HOO palette. Widefield shot in Cygnus. Canon EOS 550D, Sigma 50-100mm F/1.8 zoom at full aperture, and Optolong L-eNhance filter on the Vixen GP mount The Veil, first with the Canon EOS 550D, APM 80mm F/6 and 0.8x reducer H-alpha mosaic with ASI294MM-Pro, APM 80 mm F/6 and 0.8x focal reducer O-III data added, same combination as above Experiment with Sigma 120-300 mm F/2.8 Sports lens I have, with the Canon 550D on M31. Stars in corners not really good. Heart and Soul, with Double Cluster, Canon EOS 550D, Samyang 135mm F/2, Optolong L-eNhance filter. Twelve hours over 3 nights Hopefully, the coming year will give some more clear nights

I use both UHC and O-III filters in my 80mm F/6. Both can really bring out more detail.

Managed to capture 12 h of data over three nights, using my modded Canon 550D, Optolong L-eNhance filter, and Samyang 135 mm F/2. STacked each 4 hour session with APP, and combined the three stacked images in APP together with weight maps. Not quite satisfied with the background (or star colours, but might combine this with RGB data), so might want to redo the flats. Still, quite happy with the performance of the Samyang 135 mm F/2, and I do like the detail captured in the nebulae. Also nice to have the Double Cluster in the FOV.

Calling it a night (work to do tomorrow), 4 hours of data captured, to go with the 8 hours captured previously. Will let the data stack away tonight

Oh well, I'll grab some more Heart and Soul wide-field with the old Canon EOS 550D and Samyang 135 mm F/2 144 minutes of data and counting. The Optolong L-eNhance filter seems to be keeping the moonlight in check reasonably well

I have my own Coronado in my office, the bigger guns are at home. It is a great job, however