Jonk

I thought exactly the same, a good run of clear nights at the worst time of the year for astro-darkness.

But, there's plenty to observe / image in the summer, even with the very short nights, it's not all about long exposure DSOs.

December. Oh dear December! I heard it was officially the cloudiest month in the UK for a very long time. There were usuable patches, but in the main it was not good at all.

In conclusion, the reason I wanted to do this was to total up the green, oranges and reds and convince myself and hopefully others that astronomy in the UK isn't all bad really!

So, totals:

Green - Clear (good astro most or all night): 45 nights

Orange - Partly cloudy (some astro possible during the night): 157 nights

Red - Cloudy (no astro possible at all: 163 nights

Although on the face of it things look bad, the way I see it is there's a clear night (all or most) at least once per week on average across the year and 1 in every 3 nights you could get out and do something during the night.

Any other thoughts? Shall I do the same again for the next 12 months?

Yep, just a matter of experimenting until you're happy.

My offset is set to 300:

The gain is 180 for 45 second exposures - I may drop the gain down and up the exposure to 60 seconds, leaving the offset where it is. It's very easy to go over the edge and saturate the edge where the sky is typically at it's brightest, especially when the transparency is poor, it washes out a lot.

Mine's still undergoing lots of testing, it's far from 'finished'.

19 minutes ago, tooth_dr said:

There doesnt seem to be an ideal gain for these camera unlike most of the other ZWO range

Have a read of this... https://www.astrobin.com/forum/c/astrophotography/equipment/zwo-asi178mc-gainoffset-combinations/

The temperature isn't that high, it will probably get up to 40+ in the summer. However, cooling it will help with the hot pixels and noise, but I have found that the longer the exposure / lower the gain for a given brightness, the better the outcome.

Mine are converted to jpg and that's it, I haven't added any stretching - which might also be why you're seeing some noise.

Firstly, cool it to a sensible level, say 5 degrees or something and see how it differs.

Looking good though!

Well, we seem to have captured yet more wildlife rather than astronomical events!

It has its eye on the ponds....

It might be possible that you can replace the mono sensor pcb with a colour one. ZWO do sell the sensor pcbs separately, and I have enquired. When they asked me how many I needed, my reply was '1 to carry out a test' but they didn't reply after that, maybe they were expecting me to say '250' or something?!

Alternatively, you could find a 178MC and swap the pcbs round. 4 screws and a ribbon cable, that's it. I can't think of a reason why it wouldn't work.

I don't have the cooler on at the moment, as there's no hot pixels really in this weather. I'm waiting for the dev team to add my feature request, which is automatically switch the cooler on at night, and off during the day rather than on or off manually. It should be easy to implement, as the software already uses a module called 'sunwait' which knows sunset / sunrise times based on your location.

I would certainly not try and seal the enclosure, or you will get trapped moisture in there, which will end up fogging the dome. No amount of heat will remove it. Mine has 2 fans below (for summer cooling) and the inside of the dome is open to air through these fans. The heater is to stop dew on the outside. It works really well and is only about 2W of power. It also helps dry the rain off, over a couple of hours.

In heavy rain, the inside of the dome does fog a little, but turning the fans on in addition to the heater sorts it out - this is something I need to automate based on humidty, which I will get to. For now, the heater is based on outside temperature.

Allskeye - I started with that and a mini pc, but it drove me nuts....kept rebooting, updating, crashing etc so I chose the PI so it only does what you tell it to. So far, it's night and day (pun intented) the way to go for me. I've had to use Python for all the automatic stuff, which isn't too bad when it works!

That's great Adam, very useful to see others' ideas.

How are you going to use this once ready, 24/7 automatic or as and when? If automatic, I would reccomend using a RPI, and having a look at the allsky software by Thomas Jacquin on github.

I now have the RPI running 24/7 with watchdogs, automatic reboots, automatic heating (cooling to come), real measured local sqm data and I'm just about to get localised weather data (from the internet) on the overlay. Basically once finished, it will be fit and forget hopefully.

(Sneeky peeky...)

In fact, as I've been doing some programming in the past hour or 2, I think the allsky has just caught another meteor? Right at the top of the image through the plough.

Exciting!

It’s nice when a plan comes together. This is the part I made…

It sits round the sensor,has an oring channel for the glass to sit on and one to compress up against the main cover.

It probably does the same thing as what you’ve done. The most important thing is sealing the main cover properly otherwise when the cooler is on it’ll fill with water through condensation. I nearly lost the sensor pcb because of that. Luckily it came back to life after some drying and pcb cleaning at work.

I also use Fusion 360 and you can import an stl file but editing them is tricky. I’ve not tried importing a 3mf.

Best thing to do is look at the stl or 3mf in Fusion and redraw from scratch if you can.

In fact, I might be able to share the Fusion file so you can work on my original part. I‘ll have a play.

14 hours ago, tooth_dr said:

I finally got some time to have a look at this.  I tried on my all sky lens, and as you have pointed out, it doesnt screw in far enough to get the required back spacing (it's either 17.5mm or 12.5mm).  I then went on and tried a T mount to Canon adaper and was able to get focus with a 18-55mm lens, but obviously the FL is much too long.  Would you buy any chance have some photos of what you have done, or even the 3d files that I could work with and print out?

 

Many thanks

Adam.

Hi Adam, I can send you the 3mf file of the part I made for the glass window when I next put my work laptop on. I was going to get rid of the window completely but it’s needed as an ir/uv cut. It looks too odd without.

All this part does is put the glass window directly over the sensor, with an oring above and below. Took a bit of fiddling to figure out but seems to work well. I need to take the camera down to adjust the sensor pcb so will try to remember to photo what I’ve done.

Oh and you’ll need some ptfe tape if you  use the aluminium t to c mount adaptor otherwise the lens floats in the threads and won’t hold focus at all. I tried multiple 3d printed adaptors but couldn’t get them right wrt shrinkage and dimensions. 

On 17/12/2021 at 00:30, Felias said:

That's all you can do with a NFT too

Not true, you can stake an nft into a pool for APY returns.

2 hours ago, tooth_dr said:

Very good. I need to get my camera out and physically suss it out.  

Go for it, even if you out it out on a tripod and keep the dew off it’s worth it.

An allsky camera is a must have for astronomers imho.

It’s a c mount, but the lens does not screw in far enough on the 178mc-cool to focus due to the glass window. I’ve made a part so the glass window is just above the sensor and 3d printed a c mount to t thread part, but it’s slightly too thin. I don’t have a thin enough o-ring for the ~0.2mm gap so I’ve made 2 more adaptors in the range to see if I can get it right when tightly screwed in.

This lens does not drift in focus at all that I can tell so it should be good once the spacing is right.

I’ve tried holy grail timelapses with a phone and they’re not quite good enough yet, but they will be one day.

What I really want is a professional sports TV camera, now they’re amazing!

Focus is off due to the lens not being screwed in fully, it's quite loose at the moment. I’m making another adaptor to get it right. It is the cooled 178MC with a fujinon 1.4mm, and I could probably do 60s without trailing or maybe more if I lower the gain.

It’s on 24/7 as I add features and optimise it every now and then, with a view to leaving it out permanently.

Imagine if even 10 years ago someone showed you this photo and said it was handheld using a mobile phone. Mad. But it is, from a couple of nights ago.

Captured this last night, I like it!

The cam's on another test run, hence out of focus, misaligned etc....

So, November - some surprising very clear nights early on, then a lot of partially clear nights. Good for getting a couple of hours in here and there. End of the month has been very poor with few opportunities.

Thanks Dan, I saw the groups.io thread - good work!

If the weather plays ball, I might try and capture this passing M3...need lots of luck on my side though.

Or. and this worked for me very well in the past - use a red filter.

I expose for 4 seconds, 2 seconds might be too much. I think you just need to experiment until you get reliable, repeatable results.

Don't forget, the atmosphere varies wildly so after a time, you will learn what's best.

You don't need round stars for guiding - I have half moons, seagulls, pint glass shaped, all sorts on my OAG - as long as the guiding software can calculate the centroid, you'll be fine.

It doesn't even need to be in good focus - when I change filter, the slight difference in focus means a slightly different shaped guide star - never had a problem.