DaveS

Thank you both.

So perhaps not quite as bad as I thought?

I think I will have another look tonight and experiment with different exposurs to give bright stars without saturation.

In why you shouldn't use 300 sec subs when imaging bright doubles  

In my defense, I have been used to trying to capture faint tidal structures around already faint galaxies, or even fainter NB structures, so tend to thin in hours, and regard a 300 sec sub as being short. I was just looking for something to image in in this horrid twilight, and thought Albireo might mage a good target.

So captured 12 x subs in short G2v, 300 sec each R, G, and 525 sec in B. The subs showed huge halos as they came in, even with Chroma filters. Ah well should be clear tonight so will give more sensible exposures, 10 sec has been suggested to me.

Yep, watched that. Love the guy's bone-dry sense of humour.

Can it trigger safe / unsafe conditions to other equipment, eg for shut down in the event of unexpected cloud / rain?

I went to a meeting regarding a parish plan, development etc. At the end I put my hand up and said I might be a lone voice crying in the wilderness, but in our development plans could we keep in mind our dark skies. Well blow me but a burly bloke next to me leaned over and said "well said", and there was general approbation.

As we were leaving a lady remarked how much she hated floodlights that come on as you pass.

So at least some others are sensitive to LP.

Oh, and I met another astronomer.

If you're looking at some dedicated software give AstroArt a go. There's a free trial, and the software itself is a lot less expensive. In my opinion it's also a bit more intuitive than PI, which did my head in, even with Warren's book.

Well done guys.

When I looked at the other entrants I realised that I need to raise my game.

looking forward to next year's  galaxy challenge.

As usual, Dr Becky has something to say on the subject

Damn! How did I miss that? Will have to catch up on iPlayer.

Ah, yes I was watching the NASA Spaceflight livestream of the FAA environmental assessment of the Boca Chica starbase.

4 minutes ago, pipnina said:

If your equipment in your signature is accurate to when you took the readings, that would be consistent with my findings between my f4 and f5 scope. If you have a slower scope the chromas are parfocal in practice... Just not when you get down to f4. Your f6.8 and f7 scopes would be very tolerant of focus position. That said, the difference between the focus position of the LRGB set and the narrowbands (and between each narrowband) was quite considerable, enough to move the middle line out of the bahtinov pattern from an LRGB to my OIII filter.

In the case of the TS apo I did find a shift, especially towards the blue. I also had to measure offsets as I had 2mm thick Baader and 3mm thick Astrodon. I have found no significant shift with the ODK, and the NB that I have done (Not a lot admittedly) shoes [OIII] and H-alpha to be in the same focus.

If you're not going with the Antlia LRGB to match the NB, then I see little reason for not going with the Baader set.

Another discussion here:

I run a set of 2" Chromas in the ODK (Bought before they became stupidly expensive) and did a trial to determine filter offsets for the autofocus, but when I found that the difference between RGB was less than the difference between runs of the same filter didn't bother going further.

Baader LRGB appear to be OK, but their "ultra narrow band" filters had reports of some worrying halos. I also (Back in 2014) had severe halos with their [OIII] filter that sent me down the Astrodon black hole.

Astronomik could be worth a look. I have a set of their LRGB and NB in 36mm unmounted in my SX wheel, but haven't had much opportunity to use them much.

And the new player in the game,  Antlia who have 3nm NB filters in addition to the LRGB set.

I have two Sesto Senso 2 focusers, one on the 3.7" TS R&P of my TS 130mm photoline, the other on the 3" Feather Touch focuser on the ODK12. The only problem I had with either was down to a mismatch between firmware and software versions, they must both be the same, else calibration won't hold.

There have been no issues regarding out of square or misaligned shafts.

A, nope, not a chance. you need a mount capable of 0.1", and put it on top of a mountain in the Atacama with laser adaptive optics.

b, yep.

There are some other channels that I subscribe to, only distantly related to astronomy 

Scott Manley, a bit of everything space related 

Sabine Hosenfelder pretty serious science 

NASA Spaceflight 

The Angry Astronaut, some serious rants!

The Everyday Astronaut, easy to watch, but he has some deep dives into rocket science.

He's not very happy.

I don't know about APP, but have you tried AstroArt 8?

Cuiv, the Lazy Geek?

And of course Dr Becky.

I've fought plenty of battles with NGC 3718, so know it's a difficult target.

listening on "Sounds". Looks like an hour long listen.

I very much doubt whether Mars has any kind of an ecosystem to trash, but we should be very careful not to damage any life that might be there.

And there is no need or point in strip mining Earth to build deep-space ships when it's far easier to get all the materials we need from the Moon, or use the Martian regolith for building.

BBC 2 Friday 17th at 9 o/c

Hour and a half with Brian Cox touring JPL with an "access all areas" pass. Should be worth a look.

Now waiting for al the inevitable negativity 🍿.

Eggs. Basket.

We should be looking to plant self sustaining colonies / outposts everywhere we can. Too many things (And not all man-made) that can wipe us out here.

Thanks Rodd.

Better calibration frames are also on my to-do list.

I tried soft binning my RGB data but it looked worse.