Gina

That was overexposed so here is a 20s image.

Another image - 45s exposure and gain of 600 (60dB - the maximum).

Swapped the Russian Adapter and short extension tube for a longer T2 extension tube with the lens only part way screwed on due to the difference in thread pitch.  I now can get focus   I'm having trouble getting sharp focus though.  The auto-focus routine worked but just got me to about where I was by manual focus though auto-focus was a lot faster.

This image is with 30s exposure and gain at 540 (54dB) 3nm Ha filter and camera temperature of -30C.

I was right - now the focus is out the other way

I wanted an extra 2mm but the nearest I can get is something like 3-4mm longer so it could well be out the other way.  One plus point - I found no dew on the lens when in the observatory so if I can sort out the focus I should be good for imaging.  Unless I find another problem, of course.

Well dark enough now to see the stars and, yes, it has cleared.  Trouble is, I can't get focus.  Which is strange because I've had this lens in use with this setup before.  The only difference is that I'm now using my new ASI1600MM-Cool camera.  I think it's unlikely that the back focus could be different.  I seem to want a mm or two more spacer so I guess I'll have to bring the rig back indoors and see if I can sort out some different extension tubes.

The front has moved a bit in the right direction   And I have the mount on and tracking in sidereal mode so I think I'm just about ready for imaging   No dew heater but I do have the funnel shaped dew shield and maybe the heat from the camera will keep the dew off.  I can only hope

Here's the current view to the east.

Without the rig on the mount there's nothing to hold the alignment for focussing so I've set up the rig on the EQ8 mount in the observatory and set up the focus approximately on a far tree using manual remote focus from Ekos.  I've checked the camera cooling and that's working fine.  I'll switch the mount on and check I can still control it from Ekos remotely.

Still cloud but there looks like a front almost slightly to the SW with clear sky SW of that.  If it moves NE wards the sky will clear.

The bolts attaching the stepper motor were too long and catching on the gear quadrant - replaced with shorter one and all well now.  Testing the focussing from Ekos showed 4000 counts moved the quadrant from one end to the other - this should be fine and may even be suitable for auto-focussing.  Next to point the camera out of the window and focus on the distant horizon.

Have rig indoors and sorting it out.  The problem was that the fuse for the RPi and rest of the electronics had blown (goodness knows why)  replaced it with a 0.5A fuse (didn't have a 1A that was in before).  Checked all voltages and they were fine (13.5v from bench PSU, 5.1v for RPi and 3.3v).  Have the camera working and the focus moves though something is catching.

The rain has gone and the sun is out though still plenty of clouds so still uncertain about tonight for imaging.  ATM I'm also not sure if I'm going to be ready because the rig is not working - not getting a LAN connection so I have some faultfinding to do.  I have the rig set up in the observatory and I think I shall have to bring it back indoors to sort out.  I have a digital ammeter on my observatory power supply and the rig is drawing just under an amp which seems reasonable.  The fan is running on the camera so that's getting power.  The electronics box has worked fine before so it seems something has gone wrong with it.

Here are some photos.

Getting this rig ready for possible imaging tonight.  Printed the gears for the lens remote focussing and ready to attach the stepper motor to its bracket.  The electronics box will be the one from the Esprit rig and temporarily attacked with elastic bands.  It's not worth making a more permanent arrangement as I'm not expecting to use this single imaging rig on the EQ8 once I have the dual rig ready.  There's no way I can get the dual rig ready for tonight as there's too much still to do to it but I expect to be working on that next.

Time to assess what still needs doing.  Still needing 3D printing are the two drive drums for the Core-XY system (if I had a better lathe I could turn them from brass or aluminium but my lathe just doesn't work well enough and 3D printing gives more accurate results).  I can't use the ones from the Pilot (which will be cannibalised to finish the Mini) as they are all different diameters.  Then the PSU, electronics box and LCD control/display need mounting plus a holder for the reel of filament.  After that it's just a matter of connecting everything up.

I have just won an auction on ebay for a 28mm f2.8 Pentax lens which I can put with my present 28mm f3.5 lens for dual imaging   Total just under £42 including postage.  It has a Pentax K mount so I'll have to sort out an adapter (make or buy).

Once I receive this lens and sort out an adapter I shall have doubles of all my lenses and this can become my main imaging rig.  At least until I finish the DIY fork mount and micro dome etc. but I can't see that being any time soon - far more important things to do (like this dual imaging rig and the Ha solar imaging rig).

I feel like I might get back to this and have a change from the couple or three projects I have been working on.  Making up the box from timber will be a nice change from messing about with 3D printers

I've put a 0.6mm nozzle in the Volcano hotend and set up for that - printing is now fine particularly with PETG.

I found a resistor with wires less than 0.3mm diameter and managed to push that up into the nozzle when hot but it still didn't clear the nozzle.  I have now put a 0.6mm nozzle in and will order another 0.4mm nozzle (or two) - it's not worth spending too long trying to recover a nozzle that costs less than a fiver.

I'm trying to go back to the 0.4mm nozzle but it's bunged up - apparently with TPU filament but I can't seem to shift it   I have it heated to 290°C and the red TPU is slowly dripping out and a tiny amount will come out when Nylon filament is pushed hard down into the nozzle from the top.  I need some 0.4mm steel wire to push through...

Table of Volcano Nozzle Sizes :-

Number of Dots    Nozzle Diameter
           0                      0.60mm
           1                      0.80mm
           2                      1.00mm
           3                      1.20mm
           4                      0.40mm

Since replacing the glass plate on the print bed of my Pilot printer I haven't been able to produce decent prints so I think I shall go all out to get this replacement printer working.  For smaller parts I can use a 0.4mm nozzle on my Titan printer.

Ah I see And thank you Peter  That's what I thought and why I'm using the scope focuser - simplest solution.

I've redesigned the motor bracket and scope ring to allow attachment to the electronics box and also designed another ring for the other end of the box.

The print bed frame has finished printing on my Titan printer and seems fine.  I reduced printing speed to ensure success but I shall be experimenting with increasing the printing speed of the second and subsequent layers.   Printing time was 2 hours as predicted.

Like my other imaging rigs this will also be controlled by an Raspberry Pi 3 with INDI drivers for the camera, filter wheel and focuser - it will also control the EQ8 mount which I shall be using until I get my DIY fork mount made.  Client software will likewise be KStars/Ekos running on my Linux Mint desktop PC.

Here are a couple of photos of the rig less the electronics box that controls the lens focus and captures the images.  Between the lens and the filter wheel are a "Russian Adapter" which converts the Pentax M42x1mm to T2 thread (M42x0.75MM) and a T2 extension tube to obtain the correct back focus for the lens.  The support brackets for the camera and lens attach to the jaws of a mount which not only grips the brackets but closes them onto the lens and camera, doing two jobs at the same time.

It wasn't my Titan printer - it was me   It's working fine now.  And I'm feeling a little bit better   A few odds and ends arrived from Ooznest including brackets for the rear XY pulleys so I've now used them to attach the pulleys.  I'll have another go at the print bed frame shortly - Titan is currently printing a bracket for the camera on my widefield single imaging rig.