knobby

Blimey, tale of horrors there 😟 glad you got it sorted though.

I've seen good images taken with C8 / HEQ5 combos so will probably go for a replacement and hope it's a better one 🤞

Are you just after a mount as the scope you have is a good one already ? What camera are you going to be using ? Check on first light optics fov calculator to see what objects will look like size wise before you go any further.

If you feel an H#*5 pr0 is too heavy how about the ioptron CEM25 ?

Good luck choosing 😃

Interesting debate ! As someone who has joined the mono party very late I can already see the benefits in astro imaging so it would be a shame if mono becomes elitist. Maybe the future is the new Tri band filters ? Still loses out on using the whole chip but a compromise.

Spoke to @FLO mount being collected on Monday, now have the weekend to decide between a replacement or go for a heavy ! EQ6R.

Cheers all, have a good weekend.

Thanks all for your help , I decided to try the mount last night with the 72ed ( thinking if it can't guide that then what chance has the C8 got ) sure enough it calibrated fine with the default ( new profile wizard ) settings . Let it guide for a bit , looked good. Ran guide assistant and accepted suggestions. Still looking good (0.8 ish) but still having occasional veers up or down to 2 ish arc seconds .😟

Log attached - I think I'll be returning it as I've lost all confidence in it to be honest.

72ed/ reducer/ZWO efw/ovl oag/zwo1600

EDIT - its a real shame as poor @FLO now have to deal with what was probably caused in China trying to catch up with stock fulfilment due to Covid.

PHD2_GuideLog_2020-05-28_222123.txt

I don't think it tracks unless you align. Just say yes to a 1 star align, don't bother actually aligning but agree to it. Should track then.

Looks good ! Did you not try the left hand / EQ firmware ? Although your idea is probably safer ( no chance of bricking mount )

15 minutes ago, Thalestris24 said:

You could explain the situation to FLO and also ask them if it's ok to check the belt tensions without affecting the warranty. You could also try and see how it behaves with a lighter scope on the mount - eg your 72ed. Well, that's what I'd do, anyway.

Louise

Thanks Louise, the 72 ed / finder guider is a good call, at least that will rule out the weight / focal length of the C8

4 hours ago, Thalestris24 said:

That looks pretty awful, Knobby! Obviously you need to get calibration right in order for guiding to work properly. I assume you've input your scope focal length ok etc. And your PA is good (I always drift align using the PHD tool 🙂 ) Maybe have a word with FLO to check what they adjusted in respect of the belt mod and, what if any, testing they did.

Louise

PA was excellent (according to Sharpcap) focal length in PHD2 was 1500mm (C8 / 0.7 reducer should be 1400mm in theory but images plate solve to 1500mm)

In defense of FLO I'm sure they would have to charge a lot more for Rowan fitting if they had to test the mount unless they had some kind of moving laser dot to test tracking ?

No testing tonight for me as cloudy.

Never tried but maybe registax or Autostakkert

3 minutes ago, michael8554 said:

Hi Louise

I can see that the belt mod removes harmonics due to the spur gears, and runs quieter, but I don't understand how it can remove the fundamental, the worm and worm-gear backlash ?

Michael

Agreed, it still has a worm drive so some backlash will still be there. Quite a lot by the looks of mine 🙂 

But seriously, I'm feeling seriously down about this, looks like another night of piddling around trying to get it to calibrate / guide.

Thanks all for your support.

32 minutes ago, Thalestris24 said:

Hi again Knobby

You shouldn't have any backlash with a belt mod - unless the belt tension is maladjusted, or you are out of balance, or have cable drag or similar. Double check that the mount still balances ok vertically. In my experience, even with a small scope the belt mod is sensitive to small amounts of imbalance. You mentioned somewhere above that you keep losing the guide star - is that because the mount is drifting away from it rather than, say, poor sky transparency? The Guiding Assistant should show how your mount+scope is behaving independent of guiding and sky conditions. What figures does it return in respect of RA and DEC behaviour? Are you sure your PA is spot on - you need good PA to get a good calibration, and sometimes you need to do several iterations.

If everything checks out otherwise then the simplest explanation will be the belt tension being off. I did my own belt mod (a few years ago now) and had to make several adjustments before I got it right. It's been excellent since 🙂 

Hope you can sort it - it's so good when it's up and running!

Louise

Guide star was poor transparency and movement when calibrating

Any thoughts on this suggestion ?

I would go back and experiment with varying the min/max moves in PHD.

Try using an RA Duration value of 150 - that equates to a max move of approx 1.25" at a guide rate 0f 0.5x.

Also increase the Calibration step size. I sample at 0.61" and find a value of 450ms gives a good calibration.

At the end of the day I think you need to spend more time experimenting with the guide settings and trying to get a god calibration as imaging at 0.52" requires very accurate guiding if you hope to get round stars.

If you get nowhere then of course you can return the mount but I think it unlikely that you will get good reliable guiding at your plate scale without some experimentation.

So, again thanks to all for input, had another crack last night ... balanced as well as possible in dec and ra, got PA to sub 1 arc min in sharpcap, chose a star near dec 0 to calibrate on and calibration was horrid again. Tried the nudge North suggested by @michael8554 which helped and then passed calibration (badly though) I've run motors round and round for ages incase something was 'bedding in' but still only guides at 1+ in ra and 0.6 ish in dec.

Attached guide logs again and will copy @FLO in by email.

Annoyingly it guides at 0.7 and 0.5 for a few minutes occasionally then has a fit randomly up to 2 ish in ra.

Cables scrunchied to side of mount head, no wind, no dew shield - C8 edge 0.7 reducer and OAG.

Really don't want to send it back 😞 pretty gutted.

edit - forgot to say, ran guide assistant and accepted suggestions.

PHD2_GuideLog_2020-05-25_140529.txt

37 minutes ago, Thalestris24 said:

Hi Knobby

Remember that with a belt mod you want very good balancing, no East heavy!

Louise

Cheers Louise, it was just a teeny weeny bit east heavy as ironically, there is a small amount of backlash in Ra.

Thanks again, it was a very rushed session inbetween  clouds, I guess I'm not being fair on the mount but just want to see it guide accurately before I've had it too long for @FLOto be able to accept it back as faulty. I was sure I pressed the accept guide assistant suggestions but clearly too rushed 😅

Edit - set up on concrete paved patio.

Thanks for the help with this, I'm just trying to sus if it's me and my garden (surrounded by houses up to about 45 degrees so fairly poor seeing or a problem with my shiney new belt modded mount. Tried again last night for about 90 mins in total including pa. Mount / scope was pretty much perfectly balanced but very slightly east heavy. Using an OAG / C8 reduced to 1500 mm ,managed to calibrate albeit poorly but the RA guiding was inconsistent and still showing high backlash although dec guiding was very good.

I,m slightly underwhelmed as my £250 Az-Gti guides just as well if not better.

Could it be my location ?

Next step for me will be to try finder guider to discount the OAG as it keeps losing stars even at 3 seconds

Logs attached and thanks again.

PHD2_GuideLog_2020-05-24_215740.txt

Hi Kris, welcome to SGL

Mono CMOS would imho give more of an improvement but also a steep learning curve 😁 you'd also need to factor in filters etc. You do open up the advantages of narrowband imaging also which helps with light pollution.

Looking forward to this ! Just deciding whether to wash my hair 😂

Not sure, but have you checked it's picking the correct com port in device manager ?

ZWO have an android app so in theory just an ZWO camera / Android tablet.

Looks good, I'd check it with and without the reducer to be safe. In theory you should be able to check it with camera or eyepiece so long as fairly high magnification.

The pole master has a screw in usb connector, mine was fine til I sold it (3 years ish) probably still is 🤞