Getting back into imaging after a long break

[Gina]

The current series of clear nights have enabled me to sort out a lot of the equipment and given me ideas for improving the imaging rig.  I may have acquired some fair to good image data too, which I plan to process in the next week.

Imaging rig improvements :-

1. Design and print focussing gears for other lenses.
2. Change the camera housing/bracket to enable the camera to be rotated.
3. Produce a dual imaging  rig.

[Gina]

3D printer has a problem with broken thermistor wire on hotend so I need to sort that out before I can do more printing.  Guess I could do with another 3D printer as spare.  I decommissioned the mini printer as I got fed up with the string drives so simplest way of having a spare printer (at least for small things) will be to change the mini printer to timing belt drive.  That will have to be after getting my Concorde printer working as it will need printed parts.

[Gina]

Took the extruder and hotend assembly apart and gave it a "full service" at the same time changing to 0.4mm nozzle and 1.75mm filament (I had been set up for large relatively coarse prints but now want to print higher resolution).  The other thermistor wire broke so I repaired both.  Reassembled it all and tested.  BUT now the thermistor is fine but the heater doesn't work!!!  Amazing!

[Gina]

Did a quick continuity check with the DMM and found one heater wire in the umbilical was open circuit - broken somewhere.  So I'll unwind the spiral wrap and replace the wire (or repair it, depending on where the break is).

[Gina]

Removed the umbilical holder from the X carriage and started unwinding the spiral wrap.  Soon found the break in the heater wire, just a few inches in.  Repaired it by stripping off the insulation, twisting the ends together and soldering followed by covering with heat shrink sleeving (previously threaded onto one part of the wire).  Put everything back together and printer is now working again.

Now printing focus gear for 135mm lens.

Edited September 22, 2019 by Gina

[Gina]

Something isn't right - the filament is jamming, so I'll have to take extruder & hotend apart again and see why.

[Gina]

Found the problem and fixed it.  Needed PTFE tube to guide the filament through the Precision Piezo Z probe where there was a fair sized cavity.  2.85mm filament is stiff enough but 1.75mm collapses.

[Gina]

Brought the imaging rig indoors in a gap in the rain ready to swap to the 135mm lens and make new camera mounting brackets that will allow the camera to be rotated.  Currently printing the 135mm lens focus gear.

[Stub Mandrel]

37 minutes ago, Gina said:

Brought the imaging rig indoors in a gap in the rain ready to swap to the 135mm lens and make new camera mounting brackets that will allow the camera to be rotated.  Currently printing the 135mm lens focus gear.

I'm printing the last bit of my cooled mono cam. I thought about what I'm doing and how easy it's been with a 3D printer and I'm tickled pink. This would have been a major undertaking without the printer and despite being printed from plastic, accuracy is assured as the sensor mounting points and camera adaptor mount are concentric and parallel by design and nothing else is critical. Can't wait to use it!

[Gina]

Now printing a new focus motor bracket to allow for the focus sleeve being further out on the 135mm lens.

The focus sleeve on the 200mm f4 lens is the same diameter as the 135mm f2.5 and the same new focus bracket will work with both.

For the dual imaging rig I shall use two of the single rigs side by side on an aluminium plate which is then bolted to the dovetail bar.

Edited September 22, 2019 by Gina

[Gina]

This screenshot from KStars shows how the Heart & Soul Nebulae fit into the fields of view of the 105mm lens and the 135mm with camera rotated.

[Gina]

Later on when Orion is up at a sensible hour and the moon is out of the way and we have a clear night, I want to imaged the region around the Horse's Head including the Flame and Orion Nebulae.  This would be with either 135mm f2.5 lens or a pair of 200mm f4 lenses.

[Gina]

I'm also planning a very wide view in Orion with Barnard's Loop.

[Stub Mandrel]

From 2015 years ago, so when I was still starting out... bottom half of Orion with my Zeiss sonnar 135mm:

And a very poor whole Orion, a jpg too, but I swear there's some sign of Barnard's loop.

 

[Gina]

I thought I had imaged Orion very widefield before and at last I have found it.  This is what I want to get more data on later.

On 22/01/2017 at 16:31, Gina said:

This is an experiment in filtering.  Ha 3nm and OIII 3nm but NII obtained by subtracting Ha 3nm from Ha 5nm. 

28mm f3.5 Super Takumar lens with ASI1600MM-Cool camera.  98 3nm Ha, 98 5nm Ha and 123 OIII 3nm subs all 60s with gain of 600 and -30C sensor temperature.  All processing in PixInsight then saved in PNG format for upload.  Calibrated with bias and dark master frames but no flats as there was no vignetting with this lens and no dust bunnies seen. 

StarAlignment used to register each set and then to register sets with each other.  DynamicCrop and DBE applied.  NII created by using PixelMath to subtract 3nm Ha from 5nm Ha - I have never tried this before.  PixelMath was then used to create the colour image using Red=H, Green=OIII*2-0.055 and and Blue=N.  Then CurvesTransformation used to pull out the nebulosity and calm the background and stars.

The Rosette Nebula can be seen in the top of the image.  Other DSOs - Barnard's Loop, Angelfish, M42/43, Running Man, Flame and Horse's Head with hydrogen nebulosity.

[Gina]

Now printing the second camera support bracket.

[Gina]

Camera with new brackets and 135mm lens all mounted on dovetail bar together with focus motor and gears.  Photos will follow when I've found out why my DSLR camera has stopped working!

Edited September 23, 2019 by Gina

[Gina]

Posted in wrong thread - again

Edited October 5, 2019 by Gina

[Dr_Ju_ju]

the curse of starting sooo many, then misplacing the current running threads......

[Gina]

Guess that's about right!!  Chatterbox - aren't I!  Maybe because I'm alone.

[Gina]

I've managed to make use of the half dozen clearish nights we've had in the last few months to sort of some of my equipment and get to grips better with the CMOS sensor, having spent years using CCDs which behave differently.  Certain things have become clear as wanting doing. 

1. Remote focussing must allow for the possibility of going further than intended and running out of rack. 
2. Want imaging rig with 200mm lens - ie. 3D printed bracket and remote focus.
3. I need a bigger filter wheel than the ZWO EFW Mini with only 5 holes - going to get the bigger one with 8 holes.
4. Need to finish getting my ASC working to see cloud.
5. Be very helpful if I could finish my ROR automation and reduce mud and ice hazard of going out to observatory.

[happy-kat]

What filters are you looking to use in a bigger filter wheel?

[Dr_Ju_ju]

I can 2nd the ZWO 8-way wheel, never had any issues with mine, even if the 1600\120 are playing up; they all run off the 1600's internal hub.

[Gina]

34 minutes ago, happy-kat said:

What filters are you looking to use in a bigger filter wheel?

Astrodon 3nm Ha, OIII, SII, Baader LRGB 1.25" mounted

[DaveS]

Be careful of the Astrodons in the 8 position wheel. Although I have successfully run them in the 5 place wheel, I have read here that the 8 place is slightly different, and that people have had trouble with them.