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the Rosette Nebula with limited data. Due to the target going out of sight from my location, and clouds covering that part of the sky when we had clear-ish nights, I never got around imaging this nebula with a blue filter. So instead of waiting for next season, I decided to combine the H-alpha, Red and Green data into a tone mapped image. So here are two mappings: HaRG and RHaG, just for fun Technical details: 12 x 4 minutes H-alpha, 8 x 5 minutes Red and 8 x 5 minutes Green. As always I used the MN190 and ASI294MM to collect the data. Processed in PixInsight Enjoy

Thanks. Regarding the rings, I will have a closer look on my computer screen, which seems very unforgiving when it comes to faint variations. The area around M81/M82 contains a lot of ifn, but from several wide field images I have seen, the ifn is very weak around this galaxy. So the data is stretched more than Jane Fonda during her 1980-ies workout period.

Thanks. I can't complain about the general darkness up here. But it's not really dark enough to go chasing ifn. @gorann imaged the area with his dual RASA and was able to capture it, but it's beyond my single MN190.

Collected more data and did a reprocess. I'm now at 19 hours total integration time L:Ha:R:G:B 378 : 304 : 150 : 160 : 150 minutes IFN is just barely visible, albeit far too weak to pull out. But it does result in an uneven background.

Herein lies the problem. Some number of communication satellites is a good thing. But too many isn't. Because too many, and FLO (or anyone else) can't do any sensible astrophotography anymore, and therefore won't need those satellites. But, how many is too many? (Btw, amateur astrophotography is only a very minor aspect of the issues at hand.) Equally important, should any one national regulatory organisation be allowed to decide on global activities that clearly also have global negative impact? Btw, I read in my newsfeed yesterday that chinese researchers are investigating ways to incapacitate starlink satellites, since they are also used (or, can also be used) by the US military. It seems to me that the we are at the beginning of a space race.

Great capture. Re the "swastika", I think it's an artifact from deconvolution. Whenever I get this kind of ridges, I back off on the amount of deconvolution I apply. In the "classic" decon routine in PI, I would increase the Global Dark and Global Bright settings. In BXT, I would reduce the strength or play around with the psf settings. Here's a reference image with good resolution. https://www.astrobin.com/lmdzt0/B/?q=Ngc 4395&camera= Btw, have you considered adding Ha? Will be a real boost. https://www.astrobin.com/full/gvdyz4/C/

Can it be dew? Just wondering since it showed up after a certain time.

Definitely. The guiding assistant will most likely provide the answers you need. In the ASIAIR mount driver/dialog there may be an entry for backlash and whether it should be taken into account. At least that's the case for Ekos on which the Air is based.

You can't enter your location and time zone into Aladin, because it's not a stellarium program. Aladin is an online database with an interactive map of skies as its interface. It's much easier to use Aladin Lite, the online version of the database. Either you scrol with your mouse or you enter the ID of a target into the entry field on the left. If you use the bullseye marker on the left, any target you click on will get a small tag. Click the name in that tag to get to the Simbad database and find information on that target. From there you can access the NASA Extragalactic Database (NED) and any publications on that target. The images that make up the user interface are from the Sloan Digital Sky Survey. Once you get to know it, it's a very powerful tool with capabilities far more advanced than anything a stellarium can throw at you.

The belt can introduce its own tracking issues. If you analyse a guide curve (phd log viewer, RA frequency analysis is the best tool for this), you may notice several periods (peaks in the frequency curve). The following applies to the AZ-EQ6, but should be similar for any Skywatcher mount. The peak at about 480 s in the frequency curve is due to the worm assembly. A 120 s peak can be associated with one full turn of the stepping motor, and a 10 s peak with the stepping motor advancing one cog of the belt wheel. If the belt is too loose, this peak gets more pronounced. Otoh, you need guiding exposure not exceeding 1 s to resolve this peak properly. You can minimise all peaks by careful backlash adjustment and careful tensioning of the belt. Phd can handle a moderate amount of (DEC) backlash and worm eccentricity, and even the 120 s period, but the very short 10 s period is almost impossible to guide out.

Yesterday we had one of those rare clear nights, so I opened the roof of my observatory and started imaging. Yay, as they say. After about 2.5 hours clouds moved in, but also an aurora, so I closed the roof and put the scope cap on. Then watched the aurora (partly behind clouds) with my daughter. So far nothing unusual. About an hour later it had somewhat cleared again, so I opened the roof once more. Went inside to do the alignment in Kstars. Failed because of lack of stars. So much for that gap in the clouds, I thought and went out to close the observatory again. Strange, it looked clear enough where I planned to do my imaging. Then I realised I had forgotten to take the cover off my scope. Fixed that and got a few frames in before the clouds really returned. It's not the first time that has happened to me. Nor the last probably. And of course, I have never, ever, not once forgotten to take the Bahtinov mask off. Definitely not once.

Good point, which I was about to make also. Where terrestrial infrastructure is concerned, nobody questions this. In fact, no company would nowadays even contemplate building their own railway network, or their own electricity network. But in space, anything goes, it seems. I can imagine the reactions if or when that superpower in the far east starts deploying its own satellite network. Or maybe they're opting for a balloon based network?

I'm doing a joint project with @gorann, imaging this galaxy in Ursa Major. He uses his RASA for a wide field view with IFN, while I participate with Ha and possibly detail in the galaxy. Unfortunately, the weathergods are doing their best to sabotage the project. So far, I have managed to collect 5 hours of Ha and 3 hours RGB, giving me this result As usual, I used my MN190 and ASI294MM for the job. Processed in PixInsight I plan to add more RGB and Luminance data, and do a proper deconvolution job with BlurXterminator to get more detail.

I'm a bit of a MakNewt fan, so an 8" or 10" Intes Micro would be nice to have ...

An embroidery hoop meets your requirements.

That's a great start on our project, Göran. Unfortunately, my contribution is very uncertain yet, if we are to believe CO.

"Run of the mill" Lithium grease. The first time I stripped down the eq3 I used spray on lithium grease, but I found that the mount actually needs a fair amount of thicker grease to work properly. Where more high end mounts have bearings, the eq3 and eq5 have teflon shims and grease to reduce friction. In other words, these mounts need the "black chinese gunk" to work properly.

I would think that if you're doing photometry on groups of faint stars, it may very well be much of a deal. Remember, unlike amateurs, professional astronomers need to apply for time on a telescope, long in advance. They only have limited time for their observations, and often can't redo an observation if the results are garbage. A satellite streak not only affects what is directly underneath, but also what is closeby, limiting the usable area of an image. Even non-reflecting satellites can affect photometry measurements, because they can pass in front of stars to be measured, affecting magnitude measurements and resulting in difficult to detect errors in colour-magnitude diagrams.

The concern isn't so much for the amateur astrophotography community as it is for the professional community, where observing time is expensive, and where it isn't always possible to redo observations. Until recently, sending a satellite into orbit was a relatively rare event, with deployment being one at a time. Now, satellites are being deployed by the hundreds per rocket launch. This may ring a bell? (Sorry for the pun)

According to an article I just received in my news feed the US government agency FCC has approved Amazon's request to put 3000 satellites into a (lower) earth orbit constellation to provide its customers with internet access. I find this disturbing. According to the article in space.com, "The company has now satisfied conditions including a plan to address issues of collision risk, post-mission disposal reliability, completion of satellite design, and orbital separation." Nothing about how Amazon will prevent their fleet from interfering with astronomical observations. https://www.space.com/fcc-approves-amazon-constellation-kuiper

Thank you, gentlemen. In the mean time, I've had the opportunity to capture Ha, but so far I haven't succeeded in combining that with the RGB data the way I want to. Next week I'll have a few days off from work, and can hopefully finish this project.

Don’t know about the eq35, but I’ve done and undone the upgrade for my eq3-pro. The problem is that the bearings are thicker than the teflon washers they are meant to replace, and the worm gear end block doesn’t really fit to the housing anymore. I didn’t see an improvement with the bearings, so removed them again.

Thank you, Dan. Glad you like it. The resolution is ok, but the object really needs a longer focal length and better seeing conditions than what Northern Europe offers.

ngc 2537, aka Bear Paw Galaxy, aka Bear Claw Nebula is a blue compact dwarf galaxy in the constellation Lynx. The galaxy has an intricate morphology, which is far too small and detailed to be picked up by my gear from a location in Northern Europe. Nevertheless, I had a stab at it. The galaxy has several interesting H-alpha regions, just waiting to be imaged by anyone with a 1 m telescope in the Atacama desert. Also in the fov is the edge on low surface brightness galaxy ic 2233. ngc 2537 is about 22 million lightyears distant, while ic 2233 is almost twice as far away, so these two galaxies are not interacting with each other. In Simbad, ngc 2537 is classified as "interacting galaxies", but I found no references for this classification. Star formation in ngc 2537 has been catalogued and modeled in this publication: https://aas.aanda.org/articles/aas/pdf/2000/15/h1871.pdf Technical data: SW 190MN telescope with ZWO ASI294MM camera 18 x 5 minutes Optolong Blue filter, 9 x 5 minutes Optolong Red and Green filters. Total exposure time: 3 hours. I had to image this object over a period of several nights due to poor weather conditions.

Also with 190MN Camera ASI294MM with Optolong LRGB filters ngc 2403 ngc 185 M101 M51 ngc 7331