Thoughts on which imaging rigs to concentrate on

[Gina]

Clouds have mostly gone but the sky is nowhere near as good as last night or the night before.  I was getting good 30s Ha subs last night but need 60s to get the same tonight.

 

[Gina]

Captured 100 60s Ha subs and now changed over to OIII, refocussed and now capturing 60s OIII subs.  Much fainter but probably useable if I take enough subs.  This image was histogram stretched in Photoshop.

Edited October 20, 2016 by Gina

[Gina]

Out again tonight until 10:30 then set up and imaging NAN area in OIII with 60s subs.

[Gina]

Clear sky and capturing more 60s OIII subs of NAN area.  Sky is reasonable but not great.  Don't seem to have any noticeable dust bunnies

[Gina]

Sky is better now

[Gina]

Gone  over to the Cygnus Loop and capturing SII subs - 60s, gain 500, temperature -30°C.

[Gina]

Looks like this session will be ending shortly - cloud coming in   Can't grumble though - collected quite a nice lot of data   Be processing it soon - just need to buy the full version of PixInsight as my trial has finished.

[Gina]

Virtually complete cloud cover now.

[Gina]

Time to consolidate with the weather forecast looking grim for any DSO imaging in the next week.  I now have a whole lot of data to analyse and have bought the full commercial PixInsight license since my trial has run out, so I shall be preparing for data processing.  I need to consolidate and organise my imaging data and re-organise my fast Linux Mint desktop machine.  There is a partition containing an older OS which is no longer required so I can recover some HD space.

Regarding imaging data, there is a lot of data I have saved from test runs which are not really wanted and with the vast amount of data captured by the ASI1600MM-Cool I shall have to be much more careful not to keep superseded data. 

The increase in imaging data over what I collected with the Atik 460EX arises from two causes.  Firstly, the sensor has a far greater resolution and secondly I am capturing many short exposure subs rather than fewer subs with longer exposure.  The latter is a result of the different characteristics of CCD and the new ZWO CMOS sensors.

Edited October 23, 2016 by Gina

[Gina]

Whether it would be worth backing up the data already stored on the HD in the Linux Mint desktop, wiping the HD and reinstalling with a nice new clean installation I'm not sure.  Just to move the astro data to an external USB HD as it is would take a very long time and rather counterproductive since I plan to dump a lot of it anyway.  No, best to go through the data and delete what I can first then make the decision.

One reason for an HD wipe and reinstall is that I have learnt things since I first installed the OS on HD.  The first installation was followed shortly after by a second OS installation on SSD and another partition leaving the first OS installation untouched.  The partition containing the old OS could be wiped and used for data.  

Another is that the current system is using a 250GB SSD for /boot and /root with /home on HD and a separate /ssdata partition on the SSD for temporary PixInsight data.  This data partition has proved inadequate for processing several hundred 32MB capture files.  I have a 500GB SSD which I'm not currently using and which I can install in the box.

The MB caters for 4 drives, currently allocated to 2TB HD, optical drive, 250GB SSD and one unused.  I had thought of just adding the 500GB SSD as an extra drive for data but I'm wondering if adding an extra HD of 2TB or greater might be better and swapping the 250GB SSD for the 500GB SSD which would need a re-installation of Linux Mint.

Edited October 23, 2016 by Gina

[Gina]

Apart from all this data and software to sort out there's hardware too.  I guess it's time to bring the camera rig indoors and sort out the dust problem.  Dust bunnies seem to come and go!

I now have the adapter for the 45mm medium format lens and that with a further EOS to T2 adapter will connect lens to FW.  May need a T2 extension tube or two.  This will want a support bracket to attach to the mount.  I shall also want supports for other lenses which are not yet catered for.

Talking of lenses, I'm considering a shorter focal length that the 28mm I currently have.  Ultra wide angle lenses for SLRs or DSLRs are expensive and I wondered if an auxiliary "focus shortening" lens would work well enough.  eg a 0.45x adapter would reduce 28mm to 12.6mm.  This would allow me to capture a significant part of the Milky Way in much more detail than the all sky camera.  Has anyone tried these adapter lenses?

[Gina]

In the next week I should receive components needed to complete the control circuit for the all sky cam dew heater and cooling TEC.  The ASC is working well with dew heating and camera cooling running continuously but this is wasteful during the daytime and not helpful when the unit is already being heated by sunshine.  After that I plan to complete the RPi control for the main imaging rig.

[Gina]

Brought imaging rig indoors, removed camera and opened sensor chamber.  Yes, a fair amount of dust inside so I took my puffer and blew it out, then screwed cap back on.  The cap has two holes on the mating face that will take this tool to tighten it (and undo it).  The tool is very useful for T rings etc. that have these two 2mm diameter holes.

[Gina]

Been looking at the astro data.  Thousands of files in dozens of folders   I'm wondering if there's any way I can short-cut the process.  One way would be to dump all data from the ASI1600MM-Cool from before a particular date.  The early stuff was basically testing rather than "real" data.  For instance, since I didn't get the 3nm Ha filter until 1st September I think I could just dump data prior to this date but hat would only save a mere 20GB out of over a TB! 

[cosmojaydee]

although it may not be a lot of data , but the stacking info could be deleted also

[tekkydave]

The Linux find command is the best. You need to know what you are doing with it though as the scope for cock-ups is big. Suggest a good google first.

[Gina]

I think I need to examine the data sets and then dump ones that look poor.  Further sorting through folders has shown there there may well be some useful data in the older stuff so I shall need to install the PixInsight full version to look at the data. 

Been looking at hard drives and external USB3 ones are pretty cheap eg. a 5TB Seagate at about £110 on Amazon.  I could use one of those for backup and save an internal SATA connection which I could use for the second SSD.  I would then have a whole 500GB SSD for PixInsight workspace.

[Gina]

18 minutes ago, tekkydave said:

The Linux find command is the best. You need to know what you are doing with it though as the scope for cock-ups is big. Suggest a good google first.

I'm confused...  (nothing unusual these days!)  What is the find command best for?

[tekkydave]

Finding files based on a multitude of criteria then performing an action on each one e.g. copy, move, delete. 

[Gina]

Ah, I see - thanks

[tekkydave]

Eg Find all jpg files under /home/dave older than 90 days and delete:

find /home/dave -name "*.jpg" -mtime +90 -exec rm {} \;

See here

http://www.binarytides.com/linux-find-command-examples/

[Gina]

Thanks Dave   That's useful

[tekkydave]

These  are good for a networked solution. I have 2x 3Tb drives in mine.

https://www.amazon.co.uk/D-Link-ShareCenter-Network-Storage-Enclosure/dp/B004AIWOXY

Edited October 23, 2016 by tekkydave

[Gina]

Yes, I agree, a NAS drive(s) would be a very good idea.  I could copy astro data from whichever client I'm using to the NAS drive and then access that for files to process.

[Gina]

So...  One of these - D-Link ShareCenter 2 Bay Cloud Network Storage Enclosure  an updated version of the one you linked to

and two of these - WD Red 3TB NAS Desktop Hard Disk Drive - Intellipower SATA 6 Gb/s 64MB Cache 3.5 Inch