Repeat exposure time in Autorun

Lenoil90

Hello, that would be great to add some exposure to a group that we can repeat for Asiair.
For example, now I use 10min for Ha, then 10min for O3 and another 10min for S2. Then I repeat with 10min Ha etc.
That would be great if we can make a group with these 3 exposure and repeat them X times to avoid creating each exposure separately
For LRGB it's very annoying as the exposure is shorter so more exposure to create.
Thanks!

WalterT

They also need to add filter offsets for this to work properly. Otherwise you’d need to refocus between each filter.

FatherAnolev

Yes I agree 100%.

This is something that packages such as N.I.N.A. offer, which has always bothered my about my ASIAir (in fact probably the only thing!) I would also like to setup short sequences for monochrome imaging, ensuring that I get at least some data with all filters during a short period of time, then continually repeat that same sequence until the clouds inevitably arrive.

And as Walter has rightly pointed out, this would also require filter offsets for quick focusing. That way I could even shoot just a couple of frames of L, followed by one frame each of R, G, and B, and then repeat all of it, only autofocusing once at the start of the night (plus temperature changes).

There's a separate thread on filter offsets already which I also commented on. 🙂

Tech@ZWO

FatherAnolev Uncheck the' group by slot' option in the autorun settings, it will shoot only one image in every sequence and then repeat until finish the quantity you set, but doesn't support filter offset for now.

FatherAnolev

Tech@ZWO

Thank you very much - this is extremely helpful.

Hopefully you can add filter offsets - then it would be absolutely perfect!

Tech@ZWO

FatherAnolev Yes, but the backlash of the EAF will affect the focus.

FatherAnolev

Tech@ZWO

I would think that a configurable backlash value in the ASIAir would be taken into account. So for example with a backlash of 10 specified for the EAF, and an offset of 20, I would imagine that it should move the focuser by 30 steps.

Also, I believe this is why it's often recommended to setup sequences such that they progresses from the filter with the lowest offset to the highest (or vice versa). This way, the focuser is always moving in the same direction, and so backlash shouldn't be a problem.

By the way, thank you very much for discussing this with me / the community. It's an absolute delight to know that ZWO is actively listening to our feedback! I'm so glad that I chose ZWO for all of my products. 🙂

w7ay

Tech@ZWO Yes, but the backlash of the EAF will affect the focus.

No, not if you always establish the reference EAF step position each time before moving by the target offset.

For example, if you start autofocusing with a high EAF position, move it down by an amount larger than the worse case backlash. Call this reference count N, and moving the count downwards monotonically, like the ASIAIR autofocus method to avoid backlash.

When later you need to move by an offset that is larger than the current focus position, you first move the EAF to a position (again, greater than the backlash) that is above N, then move down to the reference N reference position. After that, moving downwards monotonically until you reach the target offset.

There is nothing magical about N, all it does is to establish a location that you need to first position the EAF above, so that all backlash is cleared by the time you start again at N.

Just test this with a shaft encoder like this that can measure the EAF shaft angle and you will see:

https://bbs.astronomy-imaging-camera.com/d/12562-5v-eaf-linearity-and-backlash

Chen