Stub Mandrel

2 hours ago, Adam J said:

I would warn you that for any of those models (I used the focuscube) you will need to modify the 130PDS focuser to allow connection as the body of the auto focuser interferes with the spider vane thumb screw. You need to cut down the pin and mount the auto focuser upside down. I got that model in the knowledge that I was going to be moving it over to the esprit 100. But to be honest for the 130PDS this is best unless you are willing to modify your focuser. 

https://www.firstlightoptics.com/astronomy-cables-leads-accessories/primaluce-lab-sesto-senso-v2-robotic-stepper-focus-motor.html

Adam

Or just flip the focuser spindle assembly 180 degrees, this also puts the focuser nearer the c-of-g of the mount.

2 minutes ago, Spaced Out said:

Thanks. I was considering upgrading the autofocuser to try and tighten things up a bit. I suspect the SW autofocuser may be the weak link for me. I was looking at this.

https://www.firstlightoptics.com/astronomy-cables-leads-accessories/primaluce-lab-sesto-senso-v2-robotic-stepper-focus-motor.html

The ZWO one is very good and doesn't carry the 'Prima Premium'.

It si abit tricky to mount (I had to shorten the mounting bar by 2-3mm)

5 hours ago, Spaced Out said:

Yes, but I'm limited by the SW autofocuser, I just don't think it is designed for holding/lifting heavy camera gear.

When you say 'it slips on the spindle' do you mean:

The spindle turns but the focuser tube doesn't move.

The autofocuser turns but the spindle doesn't rotate and the tube doesn't move.

The autofocuser doesn't turn and the stepper 'skips' steps?

If the second of these the universal joint between stepper and spindle needs to be tightened up.

5 hours ago, Spaced Out said:

If I could tighten the spindle tensioner any more I would but then the SW autofucuser just slips and is useless.

Have you seen this document (google found it somewhere on here, I can't find the thread):

https://stargazerslounge.com/applications/core/interface/file/attachment.php?id=301468

Near the end it explains how the teflon block adjusting screws, if too tight, can cause slippage when you tighten the pressure screw.

15 hours ago, Spaced Out said:

Well after a weekend of research it seems there is not an easy solution to my focuser sag problem on the 130PDS.

What approaches have you taken to adjusting the focuser?

There are many screws and it is easy to adjust the wrong one. As well as screws holding the spindle block in position (with 0-rings to allow for misalignment) tehre are also scres that adjust the alignment of the focuser spindle which must sit level on the focuser tube flat for maximum effectiveness.

All conventional crayfords rely on solely on pressure from the screw (or screws) that press the focuser spindle against the bearings OR the lock screw. The lock screw is not central to the bearings and may not hold the tube as accurately. Have you tried tightening the spindle adjusters until it starts to go stiff, then backing off a tiny amount?

Also, is it sag or mis-alignment? If the secondary isn't well placed or collimation is off, this can tilt the focal plane.

It's also possible the bearings are mis-adjusted - there are two screws opposite the spindle on the focuser body, these should be set so the tube moves freely and doesn't bind or scrape against the tube.

It's also possible the focuser isn't aligned straight. Each of the three screws holding the focuser body to the mounting plate has a grub screw next to it. Each pair of screws can be adjusted together (slack off the main screw before adjusting the grub screw) to tilt the whole focuser into accurate adjustment.

Most people never need to touch these adjustments, but if your focuser is off, it may be that they need attention.

The reason I ask is I have imaged with very heavy rigs hanging of the focuser with no signs of sag, and with something like 16 screws  that can potentially affect sag or alignment (not allowing for the 13 involved in collimation which could also be a problem) it is pretty easy to run out of patience or ideas before actually tracking down the source of the problem.

On 03/03/2020 at 15:07, mos6522 said:

I hate bumping an old post, but I am seeing the EXACT same problem as this thread is talking about. 

My Bahtinov mask is showing the exact same "bananas". I figured this was a problem with my mask that I 3D printed. It looked clean, but maybe it wasn't sort of thing. But no matter how much I zoomed in, looked at other stars in the field, and looked at varying brightness on different gains, and they all look the same, bananas. 

 

Sorry, I've now had this problem myself and the answer is ridiculously simple: the scope needs collimating. It's a quick and reliable cure.

Managed seven quick snaps a couple of nights ago, had to stack them manually so Venus is a bit odd-shaped...

Not impossible to do, but buying a new nylon or brass gear will be more reliable for such a small, highly stressed part.

If you post the outside diameter, measured as accurately as possible, I can point you at a likely source.

Aha! Found it in the end 🙂

6 hours ago, mAnKiNd said:

Take a look at my setup (if you're not blinded by the lights!). Camera parallel to counterweight bar, evoguide locked down on top dovetail of mounting rings.

 

Another good option would be keep to your mini guide scope on the findershoe for Sharpcap polar alignment routines and get and off-axis guider.

 

Hth

Well done for coping with those lights! I use a 30mm long  'dewshield' made from camping mat lined with black flock; I bet if you used something like that you might see improved contrast.

11 hours ago, Heizel said:

Hi 130 pds owners i have mini guide scope 30mm 132 FL with asi 120 mini mono camera. It will be enough for guiding this little beast or i should buy somenthing bigger? Enyone trying to guide 130pds with mini guide scope?

Worth having a try.

I use a 50mm x 183mm guide scope which is probably a bit more reliable and on a good day gets ~ 0.60" (someone I know with a  similar setup gets 0.40" grr...)

47 minutes ago, Thalestris24 said:

It's ok - I sorted it. Problem was caused by loose rollers under the bed.

Thanks anyway 🙂 

Louise

Yes... I read the last page after posting...

On 19/02/2020 at 23:24, Thalestris24 said:

FWIW, here are mine:

Sorry it's a bit crooked - the printer is actually horizontal, honest!

The springs don't look particularly strong - spring length as is , is about 15mm

Louise

ps a slight knock of the wheel nuts can change the bed level. They are very loose to the touch, so to speak

Assuming there isn't a single fixed point, try shortening all of the springs by the same number of turns until you can feel they are supporting the bed securely.

Still looked really puny last night. I was surprised my companions had not heard the news!

17 hours ago, Lancebloke said:

I just had my first attempt at m42 this evening. The histogram looks like I blew out the image a little bit but it came out ok with a quick bit of processing.

But to compensate you got plenty of the faint stuff. Tip, when doing M42, get the main data, then quickly take 20-30 images each a 10 seconds long. That's plenty to give you a 'trapezium' layer to blend in.

Having used the Skywatcher CC for a few years, I think the issues are overstated.

Yes, you do get a faint blue patch 180 degrees around from Alnitak when you image the flame and horsey.

It's not an issue in narrowband or even with the L-enhance, and I haven't seen the problem anywhere else, not even M42.

It's big advantage is that 'it just works' no messing with adjusting spacers, just fit a t-mount + dslr or for an astro cam get the image plane 55mm back.

Example with L-enhance and DSLR - no sign of a reflection.

4 hours ago, Simon Dunsmore said:

Hi Guys, 

I know that this is an old thread. Really impressed with everyone's results with the 130. I was wondering, as I already own a EQ5 pro mount and canon 60d if I could get away with the adding a 130pds for astrophotography? Will the mount suffice? 

Thanks for your help 

Simon 

Yes.

I managed with an EQ3-2 for a few years before getting an HEQ5.

On 07/02/2020 at 06:35, spikkyboy said:

The bright orange reticle is so bright that I cant see ANY stars through it. Just the orange circle. Shame there is no way to turn it down. If I turn it off I cant fine align.

Turn it off and find polaris, focus sharply, then turn it on.

How about this? I've used an assymetric blur kernel and deconvolution, then

extra de-noising.

1 hour ago, mikey2000 said:

Being extra fussy, maybe the stars are a little elongated, in what looks like the RA axis/direction

They are aren't they.

Strange, I was getting ~1.14" RMS which is less than  the pixel scale of my camera. Time to check my subs...

Hmm... they all show that amount of trailing!

I did lose guiding a few times that evening, it looks like those are either 5-minute unguided subs or something was moving - but if it was it was very consistent.

On the 6 Feb. 130P-DS & ASI1600. 14 x 300s, Ha.

I wouldn't get over-excited. The dimming is caused by reconfiguration of the Dyson sphere.

Here's my HSO M42. Wasn't sure if it would work, but a few things stand out - there's barely any Oiii in M43, the Sii signal is faint so it picks out eth trapezium really well, and the Ha signal gets a lot more faint stuff than a straight L - at least with my light pollution. Improvements with more narrowband processing experience await...

Are the challenges over?

Have we admitted defeat in the face of Perma-Cloud?

Here's something you don't see on this thread very often - the Moon.

This shows off the capabilities of the 130P-DS pretty convincingly.