SW EQ5 guide erratic behaviour: what to inspect? (guidelog attached!)

[Gib007]

Fair enough. Do remember the EQDirect cable is £23 or so. Moreover, it unlocks the ability to use AstroTortilla and that's golden stuff. No more star alignment - just point to your target, miss, let AstroTortilla centre it for you from a short test exposure and you're good to go in a few minutes. 

[rofus]

Fair enough. Do remember the EQDirect cable is £23 or so. Moreover, it unlocks the ability to use AstroTortilla and that's golden stuff. No more star alignment - just point to your target, miss, let AstroTortilla centre it for you from a short test exposure and you're good to go in a few minutes. 

Astrotortilla is something indeed I never checked! Seems interesting (reading through your tutorial  ) and not that difficult.

Question is if it works with the usb/serial I have...I'll investigate 

Now all that I can use to make things simpler is more than welcome!

[Dave_D]

it works just fine and dandy going through the handset

[Gib007]

True, AstroTortilla actually communicates with the mount directly with ASCOM. If that communication already works for EQMod through the handset, then AstroTortilla and every other program should work through the handset as well. 

[rofus]

I'll try it, for now I tested my actual configuration, re-cabled all the mount/equipment in a ready to use configuration that I can use to switch from ST4/Mac to EQMod/Pulseguide instantly just disabling the PC Direct mode on the remote, so during a session I can decide which one is the best guiding.

I updated all the software and tried remotely, with one single USB cable going to my Mac inside home I can now remotely slew, guide and image, so I'll first use this new perfectly tested configuration and then I'll try as well AstroTortilla.

Now I also have to learn Pixinsight, I obtained excellent results stacking through DSS and then using Startools, but I think I'll get more with Pixinsight as it's 64bit and on Mac opens in a second the huge 32bit TIFFs produced by DSS.

Tonight might be clear...time to take out the 150" refractor...

[Lonestar70]

Tonight might be clear...time to take out the 150" refractor...

Are you going to mount this on the EQ5?      

Keep happy.

Sandy.

[rofus]

Are you going to mount this on the EQ5?      

Keep happy.

Sandy.

To be honest I never saw the problem, and indeed there's no problem at all, it's 1:30h I'm guiding without a single problem (and imaging with my Nikon D90), after my usual polar alignment (without drift just polarscope) and 3 star alignment on Synscan. The mount is level and legs short, scope is evenly balanced on both axis, the tube is compact (750mm focal) so it stays balanced on all positions.

The total load of the scope, small guidescope + guide camera, Nikon D90 (plus battery pack!  ) is probably around 8kg tops, the two 5kg cw are quite up the bar. I'm not an expert but learnt a lot years ago spending countless nights with a friend who worked for ESA and was building himself his mount controllers, remote firmwares and what not. He told to not care about mount limits (within reason) because they are made to sell the higher ones, and once you're balanced then you can load a lot before having a problem (again within reason). Difference is in the motors precision most of all, but with a short focal length (up to 1200mm/1500mm) then it's not a problem 

When I loaded my Startravel150 on the EQ5 and balanced it with two cw and all the rest of equipment, I honestly felt that the mount was actually BETTER working instead that with a lighter scope. It feels more compact, less vibrations, more stable on the ground, and indeed is guiding beautifully (OSC 0.49 and going down, RMS 0.09) and imaging perfectly 

I'm sure I could add maybe another kilo or two without problems (thinking about a double attach to have both guidescope and finderscope at the same time) 

Maybe I'm lucky? 

[Lonestar70]

Hi Rofus,

You obviously missed the joke...

Quote

Tonight might be clear...time to take out the 150" refractor...

As in 150 inches = 12.5 ft aperture... now that would be fun on an eq5.

Anyways, it's good to see you have got the 150mm working so well and I hope you can get some clears skies to make use of it.

Best regards.

Sandy.

[rofus]

Hi Rofus,

You obviously missed the joke...

As in 150 inches = 12.5 ft aperture... now that would be fun on an eq5.

Anyways, it's good to see you have got the 150mm working so well and I hope you can get some clears skies to make use of it.

Best regards.

Sandy.

Touche! 

Even more because of what I wrote about the size indeed! 

I just wanted to underline for newcomers that they should not really be scared about spending loads of money on giant mounts or giving up because if they don't do a drift alignment then they cannot do astrophotography   I read a lot of stuff just because the book says so, but it's not true and things are much simpler. In my case and when I was with the local astronomy society, 99% of problems were all because of not updated software (on computer or firmwares) or some other software setting, like in my case    

I think newcomers should more understand that maybe a 1200mm tops is recommendable to start, and a £300 second hand EQ5 Synscope is more than enough for DSO AP.

After spending couple of hours ONCE aligning the polarscope and understanding the discs, it's really maximum 1h the time needed to take it all outside, polar align, assemble/balance, 3 star alignment, focus camera with bahtinov mask, connect camera/guidecamera/mount to a usb hub fixed on the mount and then is all about a single cable to a computer inside home to start imaging with a nice tea 

I see you use a D90 as well! Love the camera and has a very low noise imho.

[rofus]

Another useful info is about the connections (USB in particular). With a decent new computer and USB3 you have no problems of powering and no need to add another charger (like others suggested in other topics), to power a camera, guidecamera and the EQMod.

I use all of those to a USB3 hub attached to the mount, a 12 meters extension USB2 cable directly into the computer. No problems because apart the guide camera (sending images in loops) the other devices have just really low power needs, and I found this a surprisingly simple solution to leave all cables ready and well tied on the mount, from which only two cables come out (power adapter for the mount and usb cable extension).

About tonight's session, now in almost 3 hours of continuos imaging I lost only one single 5m shot, for a sudden peak in RA (who knows why!), other than that the whole thing guided spot on almost flat lines in RA and DEC all the time 

[rofus]

Hello everyone,

after second night with full setup/full load/imaging I just want to say THANK YOU to everyone here who helped me during initial frustrations with autoguide. All your suggestions helped me understanding more about principles of autoguiding, and each and everyone (helping or not to solve the issues) definitely made set my guide at its possible best.

A particular thank you to Kayron Mercieca of Light Vortex Astronomy (http://lightvortexastronomy.blogspot.co.uk/) because thanks to his article I knew in detail about the Orion package, understood it was the system for me, his kind and encouraging suggestions here made me fight more for a solution, and now I have a guiding able to perfectly keep pinpoint stars virtually for hours, opening a whole new world for me.

I can't express how happy and excited I am, I feel that now being able to take subs of virtually unlimited length (last night 3,5h of 5 to 10 minutes subs only 1 trashed!) and learning properly Pixinsight my astrophotography will gear up a lot.

Thanks again, another step to a dream became true! 

P.S. for anyone reading this message for a solution, I repeat for me solution to guide with Orion Magnificient Mini Package and Skywatcher EQ5 was:

1) set the Autoguide Speed on Synscan handheld to 1x if using camera ST4 (or if using EQMod with a serial/usb, set DEC guide to 0.9x and RA guide to 0.5x on EQMod and PC Direct Mode on handset)

2) update the Synscan handset firmware to latest update

3) update the Motor Controller firmware of the mount to latest version

[Christopher Davenport]

Really excited to hear that you have this sorted, so three final tips for you.

Tip 1.)  RA accuracy - or east heavy.

When approaching the Meridian, put weights about 3 finger widths further down the shaft from the balance point. (Opposite true post meridian)

This makes the mount lift the weight (or scope post meridian) and keeps the teeth in the worm drive engaged.  

Tip 2.) Dec accuracy - Polar misalign altitude

Polar align using PHD2, 

http://openphdguiding.org/man/Tools.htm#Drift_Align

On the altitude adjustment force the dec corrections to stay just below the line, slightly at a downward correction angle.

This makes sure that all dec adjustments are in one direction, stops yo, yo from happening in DEC.

Tip 3.) Worm drive cycle - PEC

The EQ5 worm drive has a fairly large regular jumps in it which can give certain images egg shaped stars.

To smooth these out EQmod does auto PEC.

http://astrocasto.blogspot.co.uk/2013/12/using-autopec-in-eqmod-to-correct.html

Using this feature, within the first +- 30min of guiding on the first four cycles (EQ5 cycles are +-7min at sideral)

You get predictive corrections so that you will always have sub pixel guiding.

Happy Days. Example screen shot

Notice the worm drive jumps in the PEC graph, plus notice that I could have made my dec error larger.

I did 3hrs 30min subs last night and had to drop 1, in first 30min while PEC training. (excluding pesting satellites)

[StarryEyed]

Rofus.

At this point I would suggest you stop trying to guide. Drift align your mount (I know this might seen time consuming) I used to guide an EQ5 and the DEC was always a problem. Anway after you are able to get a steady 10mins with no drift use your guide camera and collect but dont guide you RA this will give you a chance to see what your periodic error is like. You are looking to see if things are really bad so bad that guiding out might be problematic. Remember no guiding here your just observing the mounts behaviour.

My EQ5 was difficult to guide in the DEC it was more productivy to drift align the mount (after some practice I could do it in less than 15mins) at the beging of the night to get 5 minutes without any drift in the DEC which in turn removed any problems trying to guide it.

You do need to "qualify" your mount to start with just to remove the possibilty that there is significant problem with it. There is not much fun in this but it will help in the long run.

Regards.

[rofus]

Hey thanks!

Yes these are all steps I'll try at some point. Only problem I have is that I don't see Celestial Equator, I was checking the polar drift but I just don't have a view there

BUT the PEC video is very useful, I'll give it a try.

When we were coding the custom PEC firmware corrector with my friend years ago in the end we realised there was no real improvement (like 90% of the time) between good autoguiding and PEC. But I'm more curious about 'seeing' it and indeed playing back predictable corrections that might help in case of no good seeing when guiding (yesterday my small guidescope was guiding 100% correct even with dew on it, what a nice system for guiding).

Last night was beautiful here, imaged no stop from 10pm to 4am when dew (and battery pack of Nikon exhaust) reminded me to go to sleep...I trashed 2 shots only! Arrived up to 15 minutes subs low iso (the limit I can achieve I think with the LP I have here) 

Really excited to hear that you have this sorted, so three final tips for you.

Tip 1.)  RA accuracy - or east heavy.

When approaching the Meridian, put weights about 3 finger widths further down the shaft from the balance point. (Opposite true post meridian)

This makes the mount lift the weight (or scope post meridian) and keeps the teeth in the worm drive engaged.  

Tip 2.) Dec accuracy - Polar misalign altitude

Polar align using PHD2, 

http://openphdguiding.org/man/Tools.htm#Drift_Align

On the altitude adjustment force the dec corrections to stay just below the line, slightly at a downward correction angle.

This makes sure that all dec adjustments are in one direction, stops yo, yo from happening in DEC.

Tip 3.) Worm drive cycle - PEC

The EQ5 worm drive has a fairly large regular jumps in it which can give certain images egg shaped stars.

To smooth these out EQmod does auto PEC.

http://astrocasto.blogspot.co.uk/2013/12/using-autopec-in-eqmod-to-correct.html

Using this feature, within the first +- 30min of guiding on the first four cycles (EQ5 cycles are +-7min at sideral)

You get predictive corrections so that you will always have sub pixel guiding.

Happy Days. Example screen shot

Guiding Graph.png

Notice the worm drive jumps in the PEC graph, plus notice that I could have made my dec error larger.

I did 3hrs 30min subs last night and had to drop 1, in first 30min while PEC training. (excluding pesting satellites)

[rofus]

Rofus.

At this point I would suggest you stop trying to guide. Drift align your mount (I know this might seen time consuming) I used to guide an EQ5 and the DEC was always a problem. Anway after you are able to get a steady 10mins with no drift use your guide camera and collect but dont guide you RA this will give you a chance to see what your periodic error is like. You are looking to see if things are really bad so bad that guiding out might be problematic. Remember no guiding here your just observing the mounts behaviour.

My EQ5 was difficult to guide in the DEC it was more productivy to drift align the mount (after some practice I could do it in less than 15mins) at the beging of the night to get 5 minutes without any drift in the DEC which in turn removed any problems trying to guide it.

You do need to "qualify" your mount to start with just to remove the possibilty that there is significant problem with it. There is not much fun in this but it will help in the long run.

Regards.

Thanks for suggestion.

At the moment I think I'm very happy the way I am...solved all problems with software/firmware updates, yesterday again almost 6 hours I never got a single problem of guiding, RMS 0.06 and OSC constantly around 0.5, calibrated without problems at each target. I even got the odd cloud passing by, guider lost star for few secs but was still spot on when found it again!

Considering I cannot do a drift alignment and that I don't need it with my 750mm focal length and up to 15/20m subs I can take with my LP, I'm instead very happy I streamlined the TOTAL setup process (including assembling whole thing) to 20 minutes total! I did it doing the 3 stars alignment through the finderscope (correctly aligned with the scope) and so I avoided refocusing camera etc., was all ready since last time, never thought before about it and saves almost 30 minutes! When slewing to objects they were pretty much near the center and needed only the usual few adjustements in EQMod to be perfectly framed 

My only scope (pun intended) was to finally be able to get images of any length I need within the limits of my local light pollution (not much but there's some), with a cheap and easy setup-once-and-forget guiding system, using my big 150mm refractor on my EQ5, all with fast setup with one cable running from the mount to inside the house so that I need to go outside only to setup and dismount. I'm very happy I did it, 3 nights and different parts of the sky and never failed. It works even more than what I needed, I'm very happy I stopped all tech tests for the guiding and I can spend again every single minute of clear sky imaging, in particular now that I can access so many more things with such long exposures 

Now...waiting to be able to afford a nice 120 or 150 ED/APO widefield and a good osc astro ccd camera 

[rofus]

Fair enough. Do remember the EQDirect cable is £23 or so. Moreover, it unlocks the ability to use AstroTortilla and that's golden stuff. No more star alignment - just point to your target, miss, let AstroTortilla centre it for you from a short test exposure and you're good to go in a few minutes. 

Hi Kayron,

once again I want to publicly say Thank You! Your article about Orion Miniguider package was the only clear one and convinced me to buy it and since then I can get long exposures (still have to find a limit!) and that alone changed the AP world for me after years of doubts.

Then I decided to try later Astrotortilla once I was getting confident with the new setup, now after many nights and sessions with guide and more and more automated setup, I decided to give Astrotortilla a try. Again your tutorial was the best one, very detailed and very easy, and got it now working with my images from my Nikon...wow!

Tonight I'll try it without the simulator in the field (well, backyard!), but it seems to work perfectly...this means I can now really mount the telescope outside, switch it on and I'm ready to go without doing anything else...and in a week I'll receive my Nikon bulb/usb cable so in BackyardNik I'll be able to automate the shooting/dithering and plate solving...

Thanks again, your tutorials really helped me improving 1000x my setup.

[rofus]

Just to 'close' this topic, I had quite a few nights sessions with my Startravel 150 on my EQ5, added Astrotortilla and BackyardNIK, basically now it's a perfect guiding system with a few minutes setup time, a dream become true.

The whole thing is tested, I attach below a couple of examples...no more than 1h of expositions, between 2 and 8 minutes subs (for Andromeda combined), all processing in PI...in the end I have now a working setup that only needs to be used more and for longer sets.

Can't wait...thanks again to everyone who helped