Gina

I tried SharpCap and that showed the right FOV so it's definitely something funny with the APT view. ROI is definitely off and I couldn't find anything else to explain it such as zoom. Anyway, I plan to use oacapture under Linux in RPi 3 when I get it sorted out.

From first principles :- width of sensor = 4656 and pixel size is 3.8 microns giving a width of 4.636 x 3.8 = 17.6mm. So the tangent of the subtended angle is 17.6 / 135 (focal length) = 0.13. Inverse tan of 0.13 is 7.4° which is what the FOV calculator comes up with. No I'm not using ROI.

Found out why I couldn't see the Cygnus Loop. The field of view is a lot less than I thought it was. I thought is was twice as big as the Cygnus Loop but it's only about half. I don't know how this can be. The FOV calculator app shows the coverage as around 7° across and the Cygnus Loop is about 3° so something is wrong somewhere. I'll have to investigate. If the FOV is indeed only about 1.5° I shall want a shorter FL lens. I have 105mm and 55mm. I feel like trying a 55mm f1.8 lens. Here's a screenshot of the APT screen with a long enough exposure (240s) to show The witches Broom and Pickerings Triangle parts.

OTOH I might be able to write my own Indi driver to work with my focuser protocol as mine handles multiple focusers for my triple imaging rigs.

Yes, I thought as much. I wonder if anyone has written one as I gather your protocol is based on EQMOD ASCOM and your focuser works with that. So a driver written for an ASCOM compliant focuser should work with yours.

Hi Dave, do you know if your focuser will will work with Indi in Linux, or would it need a special driver?

Would seem not - unless the system was working hard to work out the size required which seem unlikely. The real answer is Linux, of course.

I guessed that would be the case Robin since you're using a lot of Windows stuff. Not to worry I'll find something

OK - found it - virtual memory - used Windows Help Size was 4055MB but system managed - help recommended custom size so I set it to 4096.

Back to desktop... Can't find swapfile - been through Control Panel and can see no mention of swapfile.

Very useful addition to an already great program - currently my favourite for setting up for AP with ZWO ASI1600MM-Cool camera and with my all sky camera with ASI178MM Now if only you did a Linux version to use with a Raspberry Pi I would be a very happy bunny

There were some gaps in the cloud so I thought I'd have another go at imaging with my current setup but the software played up again needing a reboot. Got the scope pointing almost right but after a couple of movements with the EQMOD buttons the mount carried on turning in dec until I switched it off as it was winding the umbilical round itself. With that I thought "nuts", shut everything down and closed up. No sign of any clear night sky in the next few days so I might have RPi control working by then. The windows laptop is driving me up the wall

I did a search and I found Amazon were the cheapest for RPis. I am definitely going down this route - just a matter of getting round to it. Don't know why I'm hesitating, I've done lots with Linux in the past. Downloaded the latest version of DSS and updated. Then added all the lights and all the darks and set it going but when processing it said only one light was accepted for processing It's been two years since I used it last and I haven't got the faintest idea of how to make it work Maybe I should download the trial of PixInsight which I gather does the lot, including stacking. If I can get used to PI it will help with the transition to Linux for processing as well as imaging.

Drive C: is just 5% fragmented so I don't think that's the problem. One thing might be lack of RAM - it's got just 4GB.

I did a defrag a little while ago but I forget which PC - thanks for the suggestion, I'll check it out.

Will all the faffing about last night I didn't get much data I suppose I should be satisfied that I got anything Result is 5 subs of 60s and 6 subs of 120s all Ha 5nm bandwidth. Next I'll see if I can remember how to use DSS etc. and see what's there. I also have a set of darks from an earlier night at the same temperature (-23°C). So I might be able to get something. The FOV includes the North American Nebula, Pelican, and Cygnus Wall I believe. I haven't tried much imaging of these before. A lot of the wasted time last night was spent restarting software and even Win 7 a number of times when things crashed. I'm thinking I might be better spending time loading one or two Raspberry Pis with the most suitable Linux distro and installing Indi. I've been reading the Indi web site and it seems relatively painless. Even getting Indi to find target and point scope at it would be a great help as it was CdC and EQMOD ASCOM software that crashed most last night. If I could use it to change filters too, so much the better. The imaging software SharpCap and APT were pretty reliable. My other problem is my main desktop also running Win 7 though the Pro version. It's just getting slower and slower and doing anything intensive like Photoshop is getting to be a right pain. I thought about getting a newer, more powerful desktop with more memory etc. but I'm not sure I want another Windows PC. Perhaps I should bite the bullet and try PixInsight for astro processing which has a Linux version. Daft thing is that I am used to Ps and like it.

Curses - rumbled

Flipped and cropped to the main objects then resized etc.

Yes, I think I noticed before that that I'm getting a mirror image. I'll reverse the image

Fog's rolled in now so that's the end of tonight's session. Got a few Ha subs so I'll see what I can do with those tomorrow (or um... later today!!).

Here's a 2m sub converted to TIFF and histogram stretched in Ps then resized to 1200px wide for upload here and saved in PNG format.

Found a DSO or at least an area of Ha in Cygnus so I'm now taking a run of subs with APT. Looked like a little bit showing with 1m subs and now increased to 2m subs.

Tried that and still no joy.

There's no moon out so I guess I could try Luminance and get much more light into the rig. The other problem is that CdC and EQMOD ASCOM keep crashing.

I dunno... Can't seem to find anything tonight. The mount is pretty much pointing the rig in the right direction but when I point it at the Cygnus Loop I just see a star field with no sign of a DSO. I've now pointed it at the main area of Cygnus and increased the exposure to 4m - I can see some Ha but this is at a much greater exposure than I was using with the Esprit.