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INDI Library v1.8.1 Released (09 Sep 2019)

Monthly maintenance release INDI v1.8.1

Exposure calculator

3 months 1 week ago
RugbyRene
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Exposure calculator #40123
Hi,

Would it be possible to have an exposure calculator for subs? Ideally it would be based on the equipment profile & target selected, then suggest the ideal exposure time.

Regards,

Rene

Sky-Watcher AZ-EQ6
Sky-Watcher Black Diamond ED80
Meade 8" LX-90
Sky-Watcher EvoGuide 50 (guide-scope)
ZWO ASI290MC (non-cooled primary camera)
ZWO ASI120MM mini (guiding)
Canon EOS 7D

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3 months 1 week ago
fenriques
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Exposure calculator #40132
hi Rene,

the ideal exposure time depends on many factors that are not known by INDI/Ekos. Mainly SQM and some feature of the camera like QE, dark current, read noise, FW depth have impact on the optimal length of the exposure.

I would rather use simulators that available online or as excel file.
I even tried to write one for myself but my personal experience is that, despite the theoretical model being perfect, the uncertainty on some inputs is affecting the results so much that an empirical approach based on trial and error is more valuable.

Ferrante

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3 months 1 week ago
kamisan
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Exposure calculator #40134
Rene,

I have similar equipment: William Optics 71 f/5.9 and Altair 290M.

With my Bortle 5 skies I regularly use 60s exposure in Luminance.
If you have Bortle 4 skies then I would recommend 120s exposure or more.
Keep your gain low. Use an Offset of 30. Does ZWO give you access to Offset anymore?

There is no harm in taking longer exposures except that more stars enter saturation.
The benefit is that you increase the SNR of everything including faint nebulosity just above the level of sky glow.
It is a trade-off.

The problem with the 290 is that it doesn't have a very deep well, only about 7000 electrons. That means it is difficult to get accurate star colors over a wide range of magnitudes. Also, the 290 is not cooled as you mentioned. This is especially problematic with summertime temperatures. I highly recommend that you capture darks BEFORE lights.

I recently purchased an Atik 314E. It is 10-year old technology but I get far superior results. Cooling but not set-point.

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3 months 1 week ago
RugbyRene
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Exposure calculator #40164

fenriques wrote: hi Rene,

the ideal exposure time depends on many factors that are not known by INDI/Ekos. Mainly SQM and some feature of the camera like QE, dark current, read noise, FW depth have impact on the optimal length of the exposure.

I would rather use simulators that available online or as excel file.
I even tried to write one for myself but my personal experience is that, despite the theoretical model being perfect, the uncertainty on some inputs is affecting the results so much that an empirical approach based on trial and error is more valuable.

Ferrante


There's a product by Skyhound called Sky Tools which seems to fit my requirements. It's not cheap at USD200. I'll probably buy it eventually but it would be good if it integrated with KStars/Ekos. It already integrates with APT and iTelescope.

Hey Jasem, would it be possible to look at how easy/hard it would be to integrate this?

R

Sky-Watcher AZ-EQ6
Sky-Watcher Black Diamond ED80
Meade 8" LX-90
Sky-Watcher EvoGuide 50 (guide-scope)
ZWO ASI290MC (non-cooled primary camera)
ZWO ASI120MM mini (guiding)
Canon EOS 7D

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3 months 1 week ago
wvreeven
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Exposure calculator #40170
SkyTools works very well and I have been using it for my visual observing for several years now. The drawback is that it only runs on Windows. It is possible to make it work on Linux and Mac with wine but it has its limitations then.


Wouter

ASI1600MM-Pro Cooled and filter wheel with a SkyWatcher Esprit 80 ED on a SkyWatcher HEQ5-Pro

ASI1600MM-Pro Cooled and filter wheel with an 8" TS Ritchey-Chrétien on a SkyWatcher EQ6-R

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