Pompey Monkey

Did you restart PI after copying the files?

There is always the azeq6 gt if you want to do visual and AP with the same mount. Skywatcher mounts are excellent value for money, easy to use, and well supported through ASCOM/EQMOD for AP.

It was, just. A clear horizon to the NNE was needed, so i went up portsdown hill for a better view.

Lovely picture and the best comet I've ever seen! I can see the same noctilucent clouds from Portchester (Hants) Too.

It will be fine. Any dust that might manage to get on the sensors window can be corrected for with flats. If you want to clean it prior to fitting the CC, just use a puffer:

I don't know how to calculate any of it But here is a nice write-up of the idea I am trying to convey. https://darkskydiary.wordpress.com/2011/05/04/twilight-vs-light-pollution/

I think it might depend on your local light pollution. If the local light smog is significantly worse than the sky brightness for nautical dark, then you might as well carry on...

As long as the dew point temperature is higher than ambient, dew can form. It is even more likely on surfaces like, wait for it, metal and glass that radiate their heat directly into space (under clear skies). The temperature of these materials can be considerably cooler than the surrounding air. This is why fans are often used on reflector primaries: passing the ambient air over the surface of the glass is actually a warming process. So, it could still be dew.

I fhi k you may need a 35 mm extension:

Hmmm. It might be time to close this thread...

In my eyes, the re-process has too much noise reduction. I prefer your original. It looks a lot more natural, although the black point is still pretty clipped. The trick is to leave just a little noise in (not that I'm much good at it myself)

If the pots and pans is confusing, try to think the of funnels with the same size small end (eyepiece or camera) but with different top diameters. Which funnel will fill a cup with water faster? A telescope effectively funnels photons into a smaller area to make the photon flux (photons per unit area, per time) greater.

The sky background will keep the same brightness. I'd <suggest> keeping your default exposure times. Maybe someone else has better info/experience on this? Also, with a 2xBarlow, you'll need 4 times the total exposure to get the same number of target photons per unit area on your sensor. But, to quote Harry Hill: "There's only one way to find out!"

How do you focus without the filter? How do you focus with the filter fitted? If you can focus, then you should at least get some stars on your subs!

Me too. It's worth paying a bit extra. Cheap USB hubs have caused me all kinds of headaches over the years, and not just in astronomy.

I concur with @steppenwolfthat this is a result of drift caused by imperfect polar alignment. However, I'm a bit surprised that these pixels did not get calibrated out on the stacking. What pixel rejection did you use? Also, dithering will soon be your best friend.

+1 for the 7-port Startech powered USB hub. The only downside is that the LEDs (like far too many devices) are a bit bright at night. It's in here, somewhere...

A (plain) t-shirt over the aperture of the scope at dusk or dawn works fine.

What @wimvb advises ^^

It doesn't matter if the polemaster is perfectly aligned with the mount. The entire point of the device is to locate the RA axis of your mount (by rotating stars on the green circle), and then aligning this axis to the NCP.

I don't agree with this diagnosis: Although the SW finder has a fairly short FL (about 180 mm), This, coupled with the 3.75 um pixels in the ASI 120m, should guide the 200P adequately. Smooth guide graphs with star trails on the main image is a classic indicator of differential flexure. I do agree, however, that a 200P on an EQ5 is pushing it for reliable guiding.

On the heq5, the 130 PDS is considered an excellent match. Very easy to attach a dslr to, to get started. Also easy to guide for longer exposures, as you find your "ap legs" Check out the "Imaging with a 130 PDS" thread in the beginners imaging section.

This happens with the generic guide scopes too. The fix i used was to add two more locking screws to secure the helical part of the focuser. The holes were already there, drilled and tapped! Just takes a bit of nerve to tweak them up tight enough without stripping the threads.....

"Turn that bloody light off!"