Skipper Billy

Depends where you live! Here in the Highlands you can have a reign of terror with a balloon on a stick. The local bobby knows us all and we all know him. Occasionally a team head this way from the big cities but its pretty rare. 

My rig runs unattended and I have a rain alarm that wakes me up if it rains.

https://www.davidbanksastro.com/equipment

4 hours ago, clarkpm4242 said:

Very nice website!!  Lots of hours put in there....

Thank you! 😉 

Ultra wide angle star trail. One nights images from my all sky camera run through star trax.

Just a bit of fun really.

58 minutes ago, robster said:

Thanks for the lovely replies....but any suggestions what I do about the limitation to 30s?

Even if the camera has a hidden Bulb setting you would still need a remote release.

If you haven't got one then you are stuck with 30 seconds until you get one.

If you have got one then its going to be a long boring night pressing the button every few minutes!

Order an intervalometer! 

Personally I would stick with 30 seconds - whizz the ISO up to 6400 or even higher on that camera and leave it running as long as you can - the Rosette will be low down in the murk by about 2300hrs so you wont get long on it as its not really dark until about 20.30hrs. On the upside the Rosette has passed the Meridian by the time it goes dark so you dont have the 'flip' to worry about 😉  2.5hrs of subs should produce a result. I would reuse your calibration frames from last night unless you have changed anything in the optical train.

I look forward to seeing your image!

Rosette Nebula (NGC 2237) Luminance gathered in late October 2019 and the RGB on 19th and 20th March. Due to the shocking imaging weather this winter this image is only 12 x 600s Lum binned 1x1 and 20 x 120s each of RGB binned 2x2. Tak 106, Atik 16200, Baader 2" filters. Processed entirely in Pixinsight. That's it for this season - what a washout!

Full res version here - https://www.flickr.com/photos/113316085@N05/49684593336/in/album-72157675109735132/

The bog standard SW finderscope works a treat - as does the Evoguide 50 - the Evoguide is made to a better quality and has a better focuser but its more expensive.

Following - I had exactly the same issue with the same scope and same collimator.

A Feathertouch isn't going to perform well if its not fitted square 😉 

It could be the focuser that isn't square or it could be the sensor. 

CCDI tends to exaggerate tilt so in reality its a very small amount.

If you try to correct it then I am happy to run images through CCDI for you so you can see if its getting better or worse!

Here you go....

The results for M109 show a very small amount of curvature and tilt.

The results for the Flame show significantly more tilt and a little curvature.

Certainly not the worst I have seen!

Cheers Gina.

Just out of interest for anyone doing the same thing.

The RPi USB wifi adapter from PiHut has improved the wifi range and signal tremendously.

The processor cooling fan from PiHut has reduced the average running temp by about 20 degrees and provides a nice warm draught inside the enclosure - should help keep the dome dew free - time will tell.

Just waiting for the new camera now!

4 minutes ago, PadrePeace said:

Skipper Billy. Did you find the fits images I pointed out? They are in the imaging forum as I first thought that would be most appropriate. Needless to say I had no comments there so moved over to this forum. 
I’ve reposted the .fits here. If you need any more just ask. 
Thanks for the offer of support. 

I didn't see you post sorry.

I will have a look at it when I get home tonight.

All the best.

David (aka Skipper Billy)

2 hours ago, Gina said:

Any further information on this?  I'm very interested to know what happened.

It seems like it was a dodgy camera. It was bought new for this task and failed right away. I swapped it out for a ASI 290mm that I usually use as a guide camera and it clattered away quite happily for 2 consecutive nights in biblical rain and wind. I purposefully changed nothing else eg USB lead etc to be sure that I wasn't masking the problem.

The 120 is on its way back to FLO and I have ordered an ASI 178MC as it seems to be highly regarded.

I have also ordered a cooling fan for the RPi and a better wifi dongle, some colour change dessicant (just in case!) and dew heater ring in case the heat from the RPi isn't enough to keep the dome clear and dry. (The RPi 4 runs really warm).

I am also going to change it from a 240v supply and 12v/5v transformer to a 12v - 5v buck and run it from a leisure battery - I dont like 240v outside and it will give me complete freedom of location. (There is a place I know a couple of miles from here that has stunning vistas and incredibly dark skies so on a really clear night I could leave it up there and pick it up next morning).

Will keep you posted.

PS - I spent a very happy couple of hours reading through your 36 page epic ASC thread! I doff my chapeau to your perseverance, patience and abilities !!

If you can post a single unstretched straight from the camera FITS file - I will run it through CCDI for you and post the result - looks like tilt in the imaging train to me.

1 hour ago, pete_l said:

It seems to me that two things happen simultaneously. At about 03:47

First you lose the right-most third of the image. Without knowing the details (such as whether this is the beginning or end of each frame - camera inverted?) it seems like the camera stops clocking out the image from the CCD and gets "stuck".

Second is that the good part of the image develops a criss-cross pattern and seems to lose the green channel. Summat to do with de-Bayering, perhaps?

I'd start looking at the USB connections and also the drivers for the camera. After that, I'd check that the camera runs OK for 6++ hours with different software.

Edited 1 hour ago by pete_l

44 minutes ago, Gina said:

At the point of the problem starting the image goes from normal to a blue/purple sort of colour and loss of the RH columns with the columns repeated from left to right.  The general image changes with changing light but corrupted.  The rainwater droplets still appear and move on the LHS of the image.

Is the camera working since?  Or is it some sort of permanent sensor damage?

Thanks both - I am at work today but will investigate this evening. 

9 minutes ago, happy-kat said:

How long were your exposures please? Like 5 seconds or less?

30 seconds.

2 hours ago, happy-kat said:

The dark subtraction worked great

1 hour ago, tooth_dr said:

Thats a great result, from a cheap wee camera.  The dark subtraction made a huge difference.

I must admit I was shocked at the improvement!

2 minutes ago, Tomatobro said:

if battery powered voltage droop?

Mains powered to 5v 10 amp transformer inside the housing.

First light for my all sky camera last night - eventually got everything working - left it running and went to bed.

Had a look at the automatically generated time-lapse this morning and it's OK until about 3/4 of the way through when something strange happens and stays like that until it shuts down at civil dawn.

Its a ZWO ASI 120 MC run by a Raspberry Pi 4.

Any suggestions?

Its not the original lens - its an Arecont 180º from the USA. The orginal lens gives about 140º

Its not a difficult project - I have never used Linux before so if I can do it - you can !

The info is here - https://www.instructables.com/id/Wireless-All-Sky-Camera/?fbclid=IwAR0MBp6cGOPtSg-HegsgeWlneg9YHLHxmzI7CjYWvm_j-UrQgEYyWSYf0J4#step1

Once I get it working properly I will post some photos and info.

Sorted - dark subtraction made a massive difference - given that to the naked eye its blanket cloud outside and I cant see a single star I am more than happy with this test ! 　It's a ZWO ASI 120MC - uncooled.

The Raspberry Pi puts out a fair amount of heat so I will wait and see if I need to add a dew hetare.

This is a great improvement......

10 minutes ago, Laurin Dave said:

Looks like hot pixels to me..  what software are you using? Can it do automatic dark or bad pixel map subtraction ?

It can do automatic dark subtraction - its not set up yet - I will try that but I wanted to be sure to know what the issue is before altering anything.

6 minutes ago, Jonk said:

Yes this is noise - it is much reduced when the sensor temperature is lower.

In experiments with / without a peltier cooling the camera body of my ZWO 178MC, there was a marked difference in cooled vs uncooled colour noise.

It also appears to be read noise - longer exposures were less noisy than multiple short ones.

If you're new to it, just experiment with all settings / exposures etc until you xero in on the best you can get, which will be different every night!

I may have made things worse than neccesary then - I have drilled holes through the base under the dome to allow heat from the Raspberry Pi into the dome in an effort to reduce dew/frost on the dome!

I will have a play.

Thanks both for your help.

I am trying to set up an all sky camera and its outside now for first light after much testing indoors.

The attached image was taken a few minutes ago and as the sky has got darker lots of coloured dots have appeared.

I have never used a colour camera before so please excuse my ignorance !!

I have turned the gain down to 50 but all it seems to have done is make the image darker - the coloured dots are still there.

Is this 'noise' or something else ??

Attached an image from just now and one from earlier when the sky was much lighter.

HELP !!

Have you got a power cable near the camera???

The 120 in my allsky camera does that if there is a live power cable near it - just a thought?  Moving the cable then rebooting cures it.

1 hour ago, Spaced Out said:

1 – When imaging over multiple nights should you take a range of LRGB frames and calibration frames on each night or can you (should you ?) spread the filters over different nights, for example one night each for each filter and the calibration frames for that filter ?

2 – Which calibration frames should I do each night ? I have a cooled camera so can create master darks and I also dither (so do I need the darks ?). I can do flats but I haven’t tried doing bias frames yet and I don’t know what dark flats are but I’m sure google will help me !

Point1. - it doesn't really make any difference whether you take one filter per night or all filters on each night - the only advantage I can see is you could shoot your Lum when the seeing is at its best and take the RGB when the seeing is not so good.  

Point 2. - Personally I take a full set of all calibration frames at the start of the season and use that library throughout that winter - then delete them when the rig comes inside for the summer. I use Flats, darks and Bias but others have different methods. If you remove the camera or move anything in the imaging train then you will need to retake them all.  Technically you should take a set of flats for each filter but in practise I have never seen any advantage over using Lum flats for all filters.

What I don't know is whether you are using a set point cooled camera - if you aren't then you might need calibration files at differing temperatures.

Most importantly enjoy it!

On 29/02/2020 at 09:52, Rocket Stars said:

It has 4 USB 3 ports, one powered for charging capabillities. I think is good for now. But for future use ov filterwheel I will maby, need mor ports Ofcoarse. Looking in to buying a Pegasus Astro powerbox, of some sort

If you need more USB ports you can just change the lid on a NUC - it takes 10 minutes and gives you another two USB ports - https://simplynuc.co.uk/nuc-lids/

I have all six ports in use - no problems.