Thoughts on which imaging rigs to concentrate on

[Gina]

Remote focuser seems fine now.  Have rig pointed at Cygnus and just waiting for gaps in the cloud.

[Davey-T]

Just now, Gina said:

Remote focuser seems fine now.  Have rig pointed at Cygnus and just waiting for gaps in the cloud.

You have gaps ? I've got rain, good luck

Dave

[Gina]

Thanks Dave    Very occasionally.  Though not at this minute.

[Gina]

Complete solid cloud cover now an just starting to drizzle so closed up and shut down for the night.  Forecast is showing a clear hour tomorrow night so might be better.  Anyway, the rig seems to be working alright now so al ready for when we do get some clear sky

[Gina]

Could have an hour or two of clear sky tonight so I've been checking that I have everything ready for imaging.  Took a couple of reboots to get the software working plus use of Task Manager to kill stuck programs a few times but I think it's working now.  APT will not handle the Atik EFW2 filter wheel so I ran Artemis Capture (from Atik), told it to ignore there was no Atik camera connected and selected the FW.  With that I was able to choose the filter.  Hopefully when I start using Linux and Indi I won't need to use lots of separate software.

The focussing is working but still a bit coarse in spite of a 22:1 gear ratio from stepper motor to lens focussing sleeve plus about 64:1 gearbox in the motor.  I could do with a higher gear ratio or maybe try micro-stepping though I've not tried that as yet with the 28BYJ-48.

Here's a photo of this little rig on the great big EQ8

[Gina]

I focussed with the Luminance Baader filter selected then chose the Ha Astrodon.  The first image shows the change in focus changing to Ha produced and the second after refocussing from the comfort of my settee in the living room.  The photos also show the change in focus count between the two - from 49 to 5.   Note - I wrote this focus control app for my triple imaging rigs hence the choice of focuser.  With this rig I have just a single focussing motor.  Zoom is at 100% as can be seen in SharpCap.

[Gina]

I've just changed filters from Ha to OIII and then to SII to check focus and although the Astrodon filters are near enough par-focal for telescopes and with larger pixel cameras, they aren't with this rig.  Focus is much more critical for this focal length (135mm) and this camera has half the pixel size too.  So when I do a three filter NB run with this rig I'll do N subs on one filter then N subs on the next etc. and I shall have to refocus between filters.  I'll have to control the process manually as it's needing two apps - one for capture (APT) and another for changing filter.

Here are 4 screenshots showing the focus shift when changing NB filters all at 100% zoom.  The different focus counts are shown. 
Ha = 5, OIII = 26 and SII = 0 for the distant tree.  The values will be different for DSOs and stars of course.

Edited August 22, 2016 by Gina

[Gina]

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.

[Gina]

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.

[Gina]

Tried that and still no joy.

[Gina]

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.

[Gina]

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.

[ChrisLX200]

The North America and Pelican mirrored!

ChrisH

[Gina]

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!!).

[Gina]

4 minutes ago, ChrisLX200 said:

The North America and Pelican mirrored!

ChrisH

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

[Gina]

Flipped and cropped to the main objects then resized etc.

[Stu]

Hurray, an image!! Well done Gina, hope you get some clear sky to put your little rig through its paces. You are definitely not under-mounted are you  

[SilverAstro]

1 hour ago, Gina said:

 I'll reverse the image

I think the first one was the real one,  just that it was photographed from the other side and you are in fact an alien.  Now you are trying to pretend

[Gina]

Curses - rumbled

[Gina]

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.

Edited August 23, 2016 by Gina

[SilverAstro]

50 minutes ago, Gina said:

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.

Defragment recently ? Is it possible that the auto defragger has been turned off ?

I dunno Win7, but Vista has a built-in defragger that is normally enabled and runs in the background but it can be turned off ( like mine is, hmm that reminds me, I must do a defrag ! )

[Gina]

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

[Gina]

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.

[sloz1664]

Hi Gina,

I had the same issue with my win 7 pc> Frustrated at it chugging away loading whilst the sky was beautiful and clear. I replaced my hard drive with a SSD drive and it is now really quick. Loads in seconds instead of agonizing minutes.

 

Steve

[Demonperformer]

2 hours ago, Gina said:

I'm thinking I might be better spending time loading one or two Raspberry Pis with the most suitable Linux distro and installing Indi.

That sounds like an interesting idea. I, too, run everything off a win7 machine (laptop), but have been considering getting another 'dedicated' machine for running everything at the scope, but the cost of (even 2nd hand) laptops would be a bit of an extravagence for me. However, a quick look on google, reveals some pi3's for sale in the £30/35 region. And not having to run windows would be an added bonus!

Do let us know how you get on, if you do decide to go down this route.

Thanks.