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INDI Library v1.9.4 Released (17 Jan 2022)

Bimonthly Stable INDI Library release introduces new drivers and fixes for existing ones. Some highlights:

Meridian flip

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Replied by Scott Denning on topic Meridian flip

For me, the key to successful meridian flips has always been to make the mount settings (either in the driver or the hand control) consistent with the way I'm asking for a flip in Ekos.

For example, set the meridian limit in the mount to something small, like 1 degree past the Meridian. This tells the mount to flip if a GOTO is executed to coordinates more than 1 degree past the meridian

Then in the Ekos scheduler, set the Meridian Flip to take place 3 degrees past the Meridian.

The mount tracks past the meridian, taking exposures. When it reaches 3 degrees west of the Meridian, Ekos issues a GOTO to the RA/DEC to which the mount is already pointing. As Hy says, it's the MOUNT (not Ekos) which then executes the flip.

This example shows why the Ekos flip setting must be FARTHER WEST than the mount Meridian Limit. The important thing is to coordinate the TWO settings: one in the mount itself and the other in the Ekos Scheduler.
Last edit: 1 month 4 weeks ago by Scott Denning.
1 month 4 weeks ago #77843

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Replied by Peter Kennett on topic Meridian flip

You state: "...set the meridian limit in the mount to something small, like 1 degree past the Meridian. This tells the mount to flip if a GOTO is executed to coordinates more than 1 degree past the meridian. Then in the Ekos scheduler, set the Meridian Flip to take place 3 degrees past the Meridian."

In my case, with the CEM120 EC2, the exact opposite is needed. If I set my mount to flip 1 degree past Meridian with the mount's hand controller, it will flip 1 degree past meridian, regardless of what EKOS is doing. If I tell EKOS to flip 3 degrees after, it will never get executed, because the mount already flipped at one degree past. This means my exposures are messed up at 1 degree past, since EKOS thinks it can wait until 3 degrees past.

I have to set my mount further west than EKOS, and it becomes a failsafe in the event EKOS doesn't flip for some reason.

iOptron CEM120 EC2 and CEM25P
Celestron C11 EdgeHD
William Optics Star71
ASI 1600Mm Pro, ASI 462MC
Moonlight motorfocus & Esatto focuser
LodeStar X2 and ZWO OAG
DewBuster
NANO PC-T4
Last edit: 1 month 4 weeks ago by Peter Kennett.
1 month 4 weeks ago #77850

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Replied by Paul on topic Meridian flip

Scott,

I think you are overly simplifying thiings.
You need to set the mount up and then configure the software to meet the requirements of the mount.
The problem is that a mount has a range over which a goto will produce a meridian flip but the software is not capable of recognising a range only a fixed limit.
So, you need to set the software to produce a flip after the first point at which it will flip but before it reaches the limit.
Since, Ekos only has one setting it needs to be set to ensure it always commands the goto before it reaches the limit.
For long exposures it may happen that it cannot achieve both and will sometimes fail, depending on when a previous exposure completes.
I have had some discussions with the programmers and they are considering adding an extra setting to fix this but it has not currently been implemented.
So in summary, to ensure 100% flips working you need to have the exposure length shorter than the period between the first point and the limit and to ensure the goto is commanded before the limit is reached.

Paul
 
Losmandy G11 with Gemini 2 controller
QSI 583/683 monochrome camera with filter wheel
Starlight Xpress Lodestar X2 guide camera
Microtouch Focuser controlled using Arduino UNO emulating Feathertouch controller
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1 month 4 weeks ago #77854

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Replied by Peter Kennett on topic Meridian flip

That is especially important with long exposures - like over 5 minutes long. Your idea is what NINA does. You set the range, and if an exposure would go over the limit, but it is too early to flip, it will pause the exposure sequence until the mount is capable of flipping. This prevents the mount from forcing a flip during an exposure.

iOptron CEM120 EC2 and CEM25P
Celestron C11 EdgeHD
William Optics Star71
ASI 1600Mm Pro, ASI 462MC
Moonlight motorfocus & Esatto focuser
LodeStar X2 and ZWO OAG
DewBuster
NANO PC-T4
1 month 4 weeks ago #77856

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Replied by Scott Denning on topic Meridian flip

Pretty sure the Ekos Scheduler will NEVER call the goto *during* an exposure.

The logic is as Hy describes. AFTER an exposure, if the hour angle is greater than the specified flip point, Ekos does a goto to the current RA/DEC. It's the mount (not Ekos) that flips.

Peter, from what you describe, your CEM120 does almost the exact opposite of my CEM40! If my mount is within the "tracking past the meridian" limit and Ekos tells it to slew to its current RA/DEC, nothing happens at all.

On the other hand, you describe your mount as performing a flip regardless of what Ekos is doing. In that case the correct thing for you is to just disable the meridian flip in Ekos and let the mont take care of it.

Remember, all Ekos can do is a goto to the current coordinates. It's the MOUNT (not Ekos) that has to know it's time to flip. Many mounts can track well beyond the meridian. If you have your mount set to track say, an hour past the meridian and Ekos tells it to slew to current RA/DEC 5 minutes or 30 minutes past, nothing will happen.
1 month 4 weeks ago #77857

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Replied by Peter Kennett on topic Meridian flip

OK, now that I am waking up - I realize my comment was not accurate at all. That's what I get for commenting whole half asleep. What I experience is NOT the mount messing up my exposures, but my DOME.
I cant figure out why - but it flips when the mount reaches some point near the Meridian. That's why my exposures get destroyed during the flips. EKOS doesn't know that the dome has moved. I don't even know WHY the dome needed to move. It just goes around and stops at the the position. There are several issues with the INDI Nexdome driver and this is just one of them.

Sorry for the confusing posts.

Peter

iOptron CEM120 EC2 and CEM25P
Celestron C11 EdgeHD
William Optics Star71
ASI 1600Mm Pro, ASI 462MC
Moonlight motorfocus & Esatto focuser
LodeStar X2 and ZWO OAG
DewBuster
NANO PC-T4
1 month 4 weeks ago #77858

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I think all the comments describe well how the MF mechanics are. Glad to hear knowledge about this tricky thing spreads :-)

Just one thing about the steps after the slew has happened. Capture re-initiates all things that where in place before the slew happened. If EKOS was guiding before, it will restart guiding. If there was an alignment, it will redo it. I.e. you do not need the scheduler for these post-flip steps to happen, it just automates them.

Not using this automation is simply more error prone. E.g. if you just turn off guiding manually before the flip happened, it won’t be restarted automatically.
TSA-120 + epsilon-160 + FSQ-85 + GSO 150/750 | Avalon Linear + M-zero | ASI 1600mm pro + 6200mm pro | KStars/INDI on Raspberry Pi 4/Intel NUC
1 month 4 weeks ago #77868

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Replied by Jarno Paananen on topic Meridian flip


Do you have hour angle selected for pier side in dome slaving parameters or mount? Later should be used if mount reports pier side correctly, hour angle is workaround for that, but causes issues near meridian when mount is on the "wrong" side.
Remote observatory running Ubuntu 21.10 x64 with ScopeDome 2M, Skywatcher EQ8, TS 8" RC, Atik 383L+, ASI178MC, ASI120MM-S, SX Lodestar X2, SX USB wheel with OAG, ZWO EAF, Gemini SnapCap, USB_DewPoint, KomaHub
1 month 4 weeks ago #77873

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Replied by MORELLI on topic Meridian flip

Hello,

This evening beeing clear, I set up my setup.
I set up 3° after meridian for thr MF on the mount and also into Ekos mount tab.
The flip occurs correctely, but capture and guiding stop and not alignment.
My mount is an iOptron GM28.
I don't success to understand how to configure mount/Ekos in order to have a well running MF.
Thank you for your help.
iOptron GM28 - ED80 SW - MAK180 SW - ASI183MM PRO -QHY224C - RPI4 4Go + Stellarmate/Nafabox/Astroberry - Focus motor DIY
1 month 3 weeks ago #77897

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Replied by Peter Kennett on topic Meridian flip

Jarno, I set the dome to MOUNT and it did the flip correctly. But then the dome stops rotating once the dome gets to zero degrees AZ. If I have it set to HOUR ANGLE this doesn't happen, but then the dome messes up the meridian flip. I have found that once the dome stops moving at zero, I can press ABORT and it will then re-sync to the correct azimuth. So I am unable to run my gear unattended.

iOptron CEM120 EC2 and CEM25P
Celestron C11 EdgeHD
William Optics Star71
ASI 1600Mm Pro, ASI 462MC
Moonlight motorfocus & Esatto focuser
LodeStar X2 and ZWO OAG
DewBuster
NANO PC-T4
1 month 3 weeks ago #77900

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Dear Morelli,
please provide the logs, otherwise it's difficult to answer.
Cheers
Wolfgang
TSA-120 + epsilon-160 + FSQ-85 + GSO 150/750 | Avalon Linear + M-zero | ASI 1600mm pro + 6200mm pro | KStars/INDI on Raspberry Pi 4/Intel NUC
1 month 3 weeks ago #77903

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Replied by MORELLI on topic Meridian flip

Sorry Wolfgang to answer lately. Unfortunetely I have any logs. I 'll change the setting next time.

I have an iOptron GM28. I can setup the MF with 2 parameters:
- Use or not the MF= Yes/No
- If Yes, how much degre after the meridian.

How do I configure the GM28 and Ekos in order to obtain the best result please ? Thank you very much for your help.
iOptron GM28 - ED80 SW - MAK180 SW - ASI183MM PRO -QHY224C - RPI4 4Go + Stellarmate/Nafabox/Astroberry - Focus motor DIY
1 month 2 weeks ago #78163

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