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Meridian flip right before totality in Texas - how to deal

55 replies to this topic

#51 JethroXP

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Posted Yesterday, 10:48 AM

Or just embrace the meridian flip and live with losing a couple of images (rather than an entire sequence)? I'll be near Uvalde; transit is at 1:41 PM and my mount can go up to an hour past meridian before flipping, so I could flip at, say, 2:40PM and just miss one or two images closer to C4 (at 2:53PM). I'd rather mess with the flip after all the real fun rather than risk messing something up before totality.

The problem is the opposite of what you are suggesting.  It’s the meridian flip that is complicated.  At night it works because after the flip it will platesolve to recenter on the target.  Platesolving doesn’t work during the day, so after a meridian flip it either won’t track because it is failing and retrying platesolving, or if you can get it out of that loop you will need to manually recenter it.  Pre-positioning in the counterweight up position is super simple.  Once you are in position and tracking there is nothing else do it, it just works.


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#52 JethroXP

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Posted Yesterday, 10:55 AM

My plan so far at least, is to use the AM5 in Alt/Az, connected to ASIair and 2600mc.  Then just use the preview mode to take an image, adjust as needed, then save it manually.

 

Trying to keep it simple so I don't waste time on the iPad instead of enjoying the complete experience.

 

Unfortunately what will likely happen is that because you are triggering shots manually you will end up focused on the iPad screen rather than actually enjoying the eclipse.  Due to the massive changes in brightness you have to adjust exposure between partial and totality, and if you are doing that manually it will become a hectic race while looking down at your gear when you’d much rather be looking up with your eyes.  I’d strongly suggest some automation, or a more traditional camera that is designed for rapid setting changes.  Unfortunately the ASIAIR is just not well suited to managing a solar eclipse.


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#53 TASCPA

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Posted Yesterday, 11:11 AM

My plan so far at least, is to use the AM5 in Alt/Az, connected to ASIair and 2600mc.  Then just use the preview mode to take an image, adjust as needed, then save it manually.

 

Trying to keep it simple so I don't waste time on the iPad instead of enjoying the complete experience.

I thought about doing this and if your rig won't work (hits the mount, etc.) using the preflip method, then AltAz would seem to be the next simplest thing.  Have you tried to run a plan in the ASIAir in AltAz?  Could set up multiple plans and then your only down time would be to switch them.  Might actually be easier than some of the custom software programming.



#54 Daniel Dance

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Posted Yesterday, 12:28 PM

Well, good news with the AM-5.

 

I ran the counterweight (well, where a counterweight *should* go) upside down for over 2 hours before the meridian flip and its still happily tracking.  No issues.

Perfect solution for getting rid of the meridian flip.

Dan


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#55 StarBurger

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Posted Yesterday, 04:30 PM

My AVX mount in stand alone configuration won't do a meridian flip. It just stops dead at a max of 20 degrees west of the meridian. This will happen "normally" before totality in my location.

What I plan to do is give the mount a false time ( say two hours earlier than reality) and two star align such that it will not do a stop for several hours before the event.

I will then de-clutch the RA axis and move the OTA forward to follow the sun without affecting the tracking or the watchful RA limits at all.

The mount will not know I have fooled it and it will track until RA limit is reached some two real hours after totality.

That's the theory but of course I will practice in my lounge before the event!

I am sure there is something I have overlooked....



#56 JethroXP

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Posted Yesterday, 05:11 PM

My AVX mount in stand alone configuration won't do a meridian flip. It just stops dead at a max of 20 degrees west of the meridian. This will happen "normally" before totality in my location.

What I plan to do is give the mount a false time ( say two hours earlier than reality) and two star align such that it will not do a stop for several hours before the event.

I will then de-clutch the RA axis and move the OTA forward to follow the sun without affecting the tracking or the watchful RA limits at all.

The mount will not know I have fooled it and it will track until RA limit is reached some two real hours after totality.

That's the theory but of course I will practice in my lounge before the event!

I am sure there is something I have overlooked....

If it stops 20 degrees west, I assume it will also hit a hard limit 20 degrees east?  Why not just pre-load it 20 degrees east and have it track from there?  





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