Date   

Re: Focuser for MaxEsp3

Ken Hunter
 

You can caarefully cut away the connecter, unsolder the pins 1 at a time and install the pins like I did in my build.


Re: Can't get less than 1" total RMS

Alexander Varakin
 

Given that the stars are round, I think the mount is not the culprit. 

I hope you realize that you are imaging at 0.56'' per pixel and that is not easy.

Possible culprits most likely are
1. Poor seeing
2. Poor focus. How do you focus ?
3. Poor optics


Yes, I use a lot of sharpening methods in PI - deconvolution and others.

Can you install demo version of PI and do DynamicPSF on your stars and share results?

Then I can compare with my results. 


Re: SHC with oled 2.4" display and bluetooh communication (ESP32 wireless)

Tong
 

Hi Gildo Bosi

Do you have the schematic diagram and the specific manufacturing method?


ESP8266 ESP-01 and external antenna

 

Hi all,

I am finishing my EM-10 onstep modification (PCBMIN1) and I am planing to have a metal face plate so the antenna need to be external.

Does anyone here have soldered an external antenna connector into the ESP-01 module?

Thanks
Andre


Re: Can't get less than 1" total RMS

Henk Aling
 

Here's a nice explanation of how the holding torque plummets with increasing microstepping that are probably not noticeable, https://www.ti.com/lit/pdf/sloa293 .  I would not be surprised if those $12 steppers of mine cause my problem.


Re: Focuser for MaxEsp3

Mike Ahner
 

On Wed, Jul 21, 2021 at 02:57 PM, Seven Jones wrote:
Yes you are right. I have used a voice cable. thats why it getting so warm.
Unfortunately, I have already soldered the RJ10 sockets on the board. Therefore, only the 4P4C plugs fit on the board side.
Should I remove the RJ10 sockets or is there another solution?
Hi Seven, you can make a test cable using a CAT-5 punch-down connector Just cut a short piece of CAT-5  a few inches long and if you want, you can remove the grey outer insulation. Then strip a little off of 4 wires (2 pair) and temporarily solder those to the bottom of the board right on the RJ-10 socket connectors. Do the same at the motor wires using the same 2 pairs of wires. Then use a standard CAT-5 cable and see what happens.

-Mike


Re: Can't get less than 1" total RMS

Henk Aling
 

On Wed, Jul 21, 2021 at 08:19 PM, Alexander Varakin wrote:
I also have G11 with AT10RC which is about #40 in total.
My RMS is between 0.6" and 1.2", depending on conditions. I am fairly happy with my images.
Here is my astrobin page, showing my images: https://www.astrobin.com/users/avarakin/
Very nice images indeed!  I noticed that your integration times are about 10 to 15 times mine.  And that you use PI, which has star minimization features.  If that explains the difference then I may be doing OK with 1" RMS?

What is the problem with your images exactly - elongated stars?
No the stars are round but larger than I like.  Blurry, not razor sharp.

Are you using OAG? With your FL, I would strongly advise switching to OAG.
Your issues may be caused by flexure in different components between the main camera and the guide camera.
Yes I have a QHY medium size OAG with an ASI120MM mini.

You will have to upgrade your camera to 174 chip in case if you go to OAG: 120 chip is tiny for OAG.
It works for me but just barely, sometimes I have to look for stars.

PHD2 works great with Kstars for me. 
I try guider of Kstars once in a while and still revert back to PHD2: PHD2 is much more robust.
Did you try the multi star guiding?  It works pretty well.  I switched to PHD2 and it gave me larger errors (this was with single star though).

Did you try collecting unguided logs from PHD2 and analyzing them using PHDLogViewer?
Once you do, you will see your periodic error and the components of it. This will help you to troubleshoot the culprits.
Yes I have used the PHD logviewer.  I use Ekos' log, it is an easy to use spreadsheet, you can plot graphs in Excel.
I wrote a Scilab optimization script to find the main frequencies in the time domain.

I doubt you need to increase micro-stepping - 2130 chip has interpolation to 256 micro-steps.
I changed it from 32x to 64x.

Your motor might be the reason for your problems too - it has pretty low torque. 
Look for threads here, there is some very good motor from Oriental motors. It is costly but has much higher torque.
Thanks that's good to know, I was wondering about that.

The trouble about building your own gear is that you can't tell the vendor that their product doesn't work because you are not using it according to spec with the vendor's tools.  I was wondering if the Gemini motors are simply stronger and work better.


Re: Can't get less than 1" total RMS

Alexander Varakin
 

I also have G11 with AT10RC which is about #40 in total.
My RMS is between 0.6" and 1.2", depending on conditions. I am fairly happy with my images.
Here is my astrobin page, showing my images: https://www.astrobin.com/users/avarakin/
What is the problem with your images exactly - elongated stars?
Are you using OAG? With your FL, I would strongly advise switching to OAG.
Your issues may be caused by flexure in different components between the main camera and the guide camera.
You will have to upgrade your camera to 174 chip in case if you go to OAG: 120 chip is tiny for OAG.
PHD2 works great with Kstars for me. 
I try guider of Kstars once in a while and still revert back to PHD2: PHD2 is much more robust.
Did you try collecting unguided logs from PHD2 and analyzing them using PHDLogViewer?
Once you do, you will see your periodic error and the components of it. This will help you to troubleshoot the culprits.
I doubt you need to increase micro-stepping - 2130 chip has interpolation to 256 micro-steps.
Your motor might be the reason for your problems too - it has pretty low torque. 
Look for threads here, there is some very good motor from Oriental motors. It is costly but has much higher torque.


Re: Focuser for MaxEsp3

Ken Hunter
 

On Wed, Jul 21, 2021 at 04:41 PM, Ken Hunter wrote:

I'll second what was said earlier about the focus motor moving VERY slow. So much in fact 
I had to use my oscilloscope to prove the motor was moving after about 5 seconds the fast
speed kicked in and the motion was then apparent.


Calculations needed for spur gear drive

Tom Gideon
 

Hi,
I'd like to configure a system for (ok...) a Criterion 4000. It's been refurbished and the optics are actually good. The main gear is a 217 tooth 48P gear being driven by a 13 tooth gear attached to a .75 RPH motor. I had to replace the motor with a 220VAC unit and I'd just as soon do away it.
I've been trying to figure out what stepper motor configuration would work and I'm stuck. Any help would be appreciated!
Thanks,
Tom


Re: Focuser for MaxEsp3

Ken Hunter
 

MaxESP3...

I have just measured my Vref voltage on my drivers. I have 2 ea LV8729 setup for RA/DEC
they have a Vref of 0.3000 volts (close enough) and 1 8825 driver for the Nema 11 Focuser
also set at 0.3000 volts Vref. I can exchange the drivers 8825 and 8729 with no other changes
and the behaviour is the same. I dislike the RJ type connectors so I have just used some pins
and sockets for very reliable connections.

I'll second what was said earlier about the focus motor moving VERY slow. So much in fact was
moving... after about 5 seconds the fast speed kicked in and the motion was then apparent.

I'm taking the liberty of sending a few photos of my system so you might see what does work
in practice. One photo shows where I have put an in-line focus disconnect to make disasembly
of the scope from the mount easier. 

Ken


Re: Focuser for MaxEsp3

Ken Hunter
 

I don't understand why you are passing enough current that the motors and wiring are getting hot.
I am using 2 Nema 17 steppers on Ra/Dec and an Nema 11 for Focuser on my MaxESP3 setup.
They have been continuously powered up on the bench for 3 weeks and its difficult to tell that they
have increased in temperature from ambient. In fact holding one that is disconnected in one hand
and a connected one in the other hand they are so close to the ambient temperature of the room
that I totally disregard the setup as far as the curent is concerned. I suppose that I could measure
the temperature rise for youThey work as they should and have given not one second of trouble.


Re: Can't get less than 1" total RMS

Henk Aling
 

On Wed, Jul 21, 2021 at 06:12 PM, Khalid Baheyeldin wrote:
Henk,

You can still set the guiding speed to 0.5X on 3.16.
From the Android app, press Guide/Focus.
From there, press the 3 dot menu, then select that speed.
Ahh.  I always use Guide/Focus for manual control by setting the rate to the maximum.  I must have jumped to conclusions as to what it is meant for.  The code actually maxes it to GuideRate1x so I guess that's why it all works.

Meanwhile I hard-coded it in my v4.24 Git branch, and it shows up as 0.5x so I'm good.  But thanks for noting that, next time it will be easier.

Note that whenever you (or any software) change the speed to 1X, that will stick and replace 0.5X.

I recommend that you use PHD2, because it will log guiding details for you, and you can use the phdlogview tool to see what is going on after the fact.
PHD2 is a pain to use with Ekos.  I have two imagers and one time it picked the wrong one, it took me a while to figure it out.  It does not know the Ekos device configurations.

Ekos also provides a log, it is simply an Excel spreadsheet which is just as easy for me at least.

I want to try PHD2 a bit more though but not on a regular basis unless I have to.

Finally, where do you live? Seeing is worse in some places than others (e.g. Great Lake area vs. Hawaii or New Mexico).
Just outside Santa Barbara, Bortle 5 or 6, and yes it had been a warm day. 


Re: Can't get less than 1" total RMS

Khalid Baheyeldin
 

Henk,

You can still set the guiding speed to 0.5X on 3.16.
From the Android app, press Guide/Focus.
From there, press the 3 dot menu, then select that speed.
Note that whenever you (or any software) change the speed to 1X, that will stick and replace 0.5X.

I recommend that you use PHD2, because it will log guiding details for you, and you can use the phdlogview tool to see what is going on after the fact.

Finally, where do you live? Seeing is worse in some places than others (e.g. Great Lake area vs. Hawaii or New Mexico).


Re: Focuser for MaxEsp3

Seven Jones
 

On Tue, Jul 20, 2021 at 07:16 PM, Mike Ahner wrote:
Seven, your 4-pin cable looks like a voice cable. Measure the resistance of the wire from each end, I think you will have a very high resistance. If so, that will cause a large voltage drop and the wire will start to heat up, as well as the motor. I don't see any reason at all that you should need a NEMA 17 or high current for a focuser, unless the focuser is damaged in someway that makes it very stiff to move.

Yes you are right. I have used a voice cable. thats why it getting so warm.
Unfortunately, I have already soldered the RJ10 sockets on the board. Therefore, only the 4P4C plugs fit on the board side.
Should I remove the RJ10 sockets or is there another solution?

Here are the steppers. left 60mm, right 30mn

The NEMA17 30mm was just too hot. You could not touch it. That's why I took one with 60mm. He is also pretty hot but not so much. And it was the only one I had.




Re: Can't get less than 1" total RMS

Henk Aling
 

On Wed, Jul 21, 2021 at 12:52 PM, "Guilherme Vênere wrote:
Phd2 offers multi star guiding which can visibly improve the guiding accuracy. I use it since it was implemented and following some suggestions from friends also using it, I decreased the exposure times to 1s only and I could see a big improvement in my GM8 with OnStep. The reason for it to work in PHd2 is the multi star guiding which can compensate for seeing errors.
Ekos also has multi-star guiding, this is what I use.

Right now with my G811G and Gemini I can get around 0.6" to 1" RMS without much tweaking which is more than enough for me. 
It depends on the FOV, with an ASI2600MC (an APS-C sized sensor) and 1380 mm FL.

Guide rates may depend on the type of issue your mount shows. In general 0.5x is the recommended rate. You can change that from OnStep web interface but the default at least in 4.xx should be that already.
Ah OK.  I am still using the old stable v3.16o but I now see on the Wiki that the stable version is v4.24.  That is great, let me switch to it.  I hope the guide rate is now configurable through Config.h.

.28" step already tells you you won't be able to achieve .25" accuracy. Maybe you need to change your gear ratios or microstep to get a better step ratio. I have the same motors in my GM8 and i use 64 microsteps with it without any problem.  
Will do.  Thanks!


Re: Can't get less than 1" total RMS

"Guilherme Vênere
 

Just a few takes at it but im not an expert.

Phd2 offers multi star guiding which can visibly improve the guiding accuracy. I use it since it was implemented and following some suggestions from friends also using it, I decreased the exposure times to 1s only and I could see a big improvement in my GM8 with OnStep. The reason for it to work in PHd2 is the multi star guiding which can compensate for seeing errors. Right now with my G811G and Gemini I can get around 0.6" to 1" RMS without much tweaking which is more than enough for me. 

Guide rates may depend on the type of issue your mount shows. In general 0.5x is the recommended rate. You can change that from OnStep web interface but the default at least in 4.xx should be that already.

.28" step already tells you you won't be able to achieve .25" accuracy. Maybe you need to change your gear ratios or microstep to get a better step ratio. I have the same motors in my GM8 and i use 64 microsteps with it without any problem.  

just my .02c

Guilherme

On Wed, Jul 21, 2021 at 9:38 AM Henk Aling <haling@...> wrote:
My system is a G11S with OnStep v3.16o, CNCv3 with TMC2130 drivers set at 32 microsteps configured for mode switching and the TMC2130_VQUIET model and 17HM15-0904S steppers (0.9 degrees).  I added DIY spring loaded worms and run it with a 12" Newt with FL=1380 mm, an OAG with an ASI120MM mini guider, altogether 50+ lbs of gear.  OnStep is controlled by Ekos with its native autoguider.  Slewing / goto works great especially with the SLW that prevent the ring gear from binding up, which unfortunately, happens a lot with Losmandy when trying to minimize the backlash.

While I read that several G11 owners achieve 0.25" total RMS, I can't get below 1" - well just once I achieved 0.49" in a session where I had mostly 0.6" over all but that was just once.  I understand that the seeing matters but so do a number of configuration parameters such as exposure time.  This makes me wonder if there is something wrong with my configuration.  I have played around enough with the SLW (also simply disabled them) and guider (tried PHD2 also) that I believe I can eliminate them as the cause.  My PA is good (I use Ekos with plate solving, similar to SharpCap), and my PE is probably around +/- 5" though this depends on the mechanical conditions such as how the worm blocks were set, how much counterbalance was provided and how tight the clutches were turned.  I have not yet started using Ekos' predictive PEC.  I counterbalance with a small extra weight or I put a hoodie over the counterweight.  Doing that cut my RA RMS in less than half (this was before the 1" RMS mentioned).  Guiding at 1" RMS makes images look pretty bad.  I believe that 0.25" RMS should be the norm.

1)  Is 32 microsteps accurate enough?  It leads to 0.28" per microstep.
2)  What is the best autoguider exposure time?  Losmandy users recommend several seconds and say that it matters.  I usually do 1 s, tried 3 s last night but it did not make a big difference (but I will try again).  A larger exposure time reduces the effect of poor seeing but can add errors due to guiding (the guider subs show clearly visible streaks in RA when RA is restless so it's a moving target and can cause unpredictable feedback).
3)  What is the best guide rate?  Cloudy Night users recommend not using 1x, which is the default AFAICT, this is how it shows up in Ekos.  It means that the motor comes to a full step or twice the speed.  Is that ideal, and if not, how can I change it?  I see no GUI in the Android client but there is code in Initialize.cpp that sets it to GuideRate1x that I could change.
4)  Any idea if the ASI120MM is too cheap a guider?  It provides noisy images, shaky too but that may be for the right reason.
5)  Should I switch to PHD2 instead of Ekos autoguiding?  I switched once and did not see improvement.

Only questions (1) and (3) pertain to OnStep, the other ones are uncertain factors that also affect the guiding performance.  Thanks in advance for your response.


Can't get less than 1" total RMS

Henk Aling
 

My system is a G11S with OnStep v3.16o, CNCv3 with TMC2130 drivers set at 32 microsteps configured for mode switching and the TMC2130_VQUIET model and 17HM15-0904S steppers (0.9 degrees).  I added DIY spring loaded worms and run it with a 12" Newt with FL=1380 mm, an OAG with an ASI120MM mini guider, altogether 50+ lbs of gear.  OnStep is controlled by Ekos with its native autoguider.  Slewing / goto works great especially with the SLW that prevent the ring gear from binding up, which unfortunately, happens a lot with Losmandy when trying to minimize the backlash.

While I read that several G11 owners achieve 0.25" total RMS, I can't get below 1" - well just once I achieved 0.49" in a session where I had mostly 0.6" over all but that was just once.  I understand that the seeing matters but so do a number of configuration parameters such as exposure time.  This makes me wonder if there is something wrong with my configuration.  I have played around enough with the SLW (also simply disabled them) and guider (tried PHD2 also) that I believe I can eliminate them as the cause.  My PA is good (I use Ekos with plate solving, similar to SharpCap), and my PE is probably around +/- 5" though this depends on the mechanical conditions such as how the worm blocks were set, how much counterbalance was provided and how tight the clutches were turned.  I have not yet started using Ekos' predictive PEC.  I counterbalance with a small extra weight or I put a hoodie over the counterweight.  Doing that cut my RA RMS in less than half (this was before the 1" RMS mentioned).  Guiding at 1" RMS makes images look pretty bad.  I believe that 0.25" RMS should be the norm.

1)  Is 32 microsteps accurate enough?  It leads to 0.28" per microstep.
2)  What is the best autoguider exposure time?  Losmandy users recommend several seconds and say that it matters.  I usually do 1 s, tried 3 s last night but it did not make a big difference (but I will try again).  A larger exposure time reduces the effect of poor seeing but can add errors due to guiding (the guider subs show clearly visible streaks in RA when RA is restless so it's a moving target and can cause unpredictable feedback).
3)  What is the best guide rate?  Cloudy Night users recommend not using 1x, which is the default AFAICT, this is how it shows up in Ekos.  It means that the motor comes to a full step or twice the speed.  Is that ideal, and if not, how can I change it?  I see no GUI in the Android client but there is code in Initialize.cpp that sets it to GuideRate1x that I could change.
4)  Any idea if the ASI120MM is too cheap a guider?  It provides noisy images, shaky too but that may be for the right reason.
5)  Should I switch to PHD2 instead of Ekos autoguiding?  I switched once and did not see improvement.

Only questions (1) and (3) pertain to OnStep, the other ones are uncertain factors that also affect the guiding performance.  Thanks in advance for your response.


Re: New Project. G11 and OnStep. Which Board, CPU.

Pete
 

Thanks Howard.  5V compatibility is always handy I'll order a Teensy 3.5.  Done.

Here's the board I ordered from JLCPCB.  I am sorry I did not specify the board.  I just figured everyone was now using the MaxPCB2, as I now shall.


Re: FYSETC S6 Focuser dosnt move #fysetc #S6

Juan Sebastian
 

Ok totally my fault, the motor was moving too slow, that i cant percive the movement, i adjusted the config, and now everithing works ok

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