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INDI Library v1.9.8 Released (29 Sep 2022)

Bi-monthly INDI Library released with new drivers and bug fixes.

New Mexico Cosmos Observatory

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Wonderful job.
The following user(s) said Thank You: Peter Kennett
1 year 8 months ago #69364

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Dreams come true!
1 year 8 months ago #69388

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Looks like you have a big backyard.

Prepare for me to set up camp there. It's just an easy 9 hr drive for me. You may want to put some more beer in the fridge....

:-)

One question, though: I don't think you are guiding through your main telescope at almost 2000 mm FL, are you? So I think the calculated RMS value is overly generous. You should substitute that with your guide scope in the drop down menu. That will probably bring your RMS into a more normal range.

I would also guide at 1x1 bin, not 4x4 bin for maximal resolution.

Looking forward to talking more about this around the campfire.

See you soon,

Jo
Atlas Pro AZ-EQ, ASI1600MM-Pro, ASI120MM-S, ES102ED, WO-Z61, Nikon D3300, ASI-EFW, ZWO LRGB,Ha,O3,S2 filter set
1 year 8 months ago #69390

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I do guide with an OAG at 1956mm focal length - f/7.
Note these are 10 second guide exposures, at the CEM120 EC2 tracks really well in between.

iOptron CEM120 EC2 and CEM25P
Celestron C11 EdgeHD and William Optics Star71
ASI 1600MM Pro, ASI 462MC
Moonlight Litecrawler (C11) and Motorfocus (WOStar71)
LodeStar X2 and ZWO OAG
Nextdome, AAG Cloudwatcher
MacMini
Last edit: 1 year 8 months ago by Peter Kennett.
1 year 8 months ago #69393

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Got it!
But 0.15 RMS feels unreal. What RMS are you getting when you do not use 4x4 binning, but 1x1 binning?

There used to be a mistake in the algorithm in which the reported RMS was simply divided by the binning factor, without making any difference to the real RMS. Both Wouter and I were mislead by this for a good while, as we were using 2x2 binning which neatly cut the reported RMS almost in half while actually worsening the true RMS through reduced resolution of guide star movement.

I wonder whether that problem has been resolved or possibly crept back in again.

Jo
Atlas Pro AZ-EQ, ASI1600MM-Pro, ASI120MM-S, ES102ED, WO-Z61, Nikon D3300, ASI-EFW, ZWO LRGB,Ha,O3,S2 filter set
1 year 8 months ago #69422

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Could be, not really sure. But I don't have a tracking issue imaging at 1956mm focal length. Examples seen above.
I have not tried 1-1 yet. But since I see no tracking issues, I'm not sure I need to. I can see errors at 0.4" easily and right now I rarely get those anymore. I am keeping about 90% of my images.

Not sure if it makes a difference, but I am in central NM at 7,000 feet altitude.

iOptron CEM120 EC2 and CEM25P
Celestron C11 EdgeHD and William Optics Star71
ASI 1600MM Pro, ASI 462MC
Moonlight Litecrawler (C11) and Motorfocus (WOStar71)
LodeStar X2 and ZWO OAG
Nextdome, AAG Cloudwatcher
MacMini
1 year 8 months ago #69423

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Seeing is definitely superior at that altitude and dry atmosphere. And whatever works!

Still, 0.15 looks unreal. At 10s exposure, you should have no problem reducing the binning to 1x1 on your guide cam without affecting the SNR much.
It would be interesting to see whether your RMS changes when you change the binning while leaving everything else the same. Testing that would only take you 20 min or so.
Atlas Pro AZ-EQ, ASI1600MM-Pro, ASI120MM-S, ES102ED, WO-Z61, Nikon D3300, ASI-EFW, ZWO LRGB,Ha,O3,S2 filter set
1 year 8 months ago #69424

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Jo,

Hy had been correcting this quite a while ago and since that day the RMS displayed made much more sense as it was basically stable no matter what binning was used. Unless that problem creeped back in.

 
1 year 8 months ago #69425

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Actually it was 10 monts ago that the issue was solved.
indilib.org/forum/ekos/6690-dubious-drif....html?start=12#51440
1 year 8 months ago #69426

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I know. I just want to make sure that the flaw has not crept in again.
An RMS of 0.15 seems too good to be true, which means it usually is....
Easy enough for Peter to test, though. Doesn't affect me, I am using 1x1 binning for guiding anyway.
Atlas Pro AZ-EQ, ASI1600MM-Pro, ASI120MM-S, ES102ED, WO-Z61, Nikon D3300, ASI-EFW, ZWO LRGB,Ha,O3,S2 filter set
1 year 8 months ago #69427

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The error has definitely crept back in.  When I guide with 1-1 I can't get close to 0.15 arc second RMS.   It's closer to 1 arc second - because it was fighting with the encoders.
With the dual encoders on the CEM120 EC2, having the error in EKOS prevented frequent guide pulses and actually made the tracking MUCH better.

But all these experiments showed me something else…. with improved Polar Alignment I no longer guide at all with met C11 at f/7 (2,000mm).  I can let the mount just track on its own with no guiding and get nice round stars even with 5 minute subs!  Here's my latest Ha image of M57 - made with 28 5-minute subs - all unguided.   If I had EKOS guiding at 1-1 - this image would have been a mess.  The mount had to have been tracking well below 0.8 arc seconds or better - consistently over 2 1/2 hours to achieve this.   These 28 frames were all that I captured.  None were tossed out from this imaging session.

 
  • C11 EdgeHD @ f/7 (1956mm focal length)
  • ASI1600MM Pro -10C
  • iOptron CEM120 EC2
  • Esatto Focuser 

iOptron CEM120 EC2 and CEM25P
Celestron C11 EdgeHD and William Optics Star71
ASI 1600MM Pro, ASI 462MC
Moonlight Litecrawler (C11) and Motorfocus (WOStar71)
LodeStar X2 and ZWO OAG
Nextdome, AAG Cloudwatcher
MacMini
Last edit: 1 year 7 months ago by Peter Kennett.
1 year 7 months ago #70550
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Very nice! Don’t forget to dither though.
Wouter van Reeven

ASI6200MM and 7 slot 2" filter wheel with a SkyWatcher Esprit 80 ED on a SkyWatcher HEQ5-Pro
ASI1600MM-Pro Cooled and 5 slot 1.25" filter wheel with an 8" TS Ritchey-Chrétien on a SkyWatcher EQ6-R
1 year 7 months ago #70551

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