Moon 25/11/23

[Graeme]

The Mid Kent Astronomical Society had an excellent talk on Lunar imaging last week and my first night time clear sky for ages was dominated by a high altitude almost full Moon, so I had a go at it!

After setting up, I used Stellerium and NINA to slew directly to the Moon. I set the telescope to Lunar tracking rate and captured 1000 x 0.003 second images. I tried stacking 980 frames in AS3 a number of times with various settings but kept getting strange blocky stacking artifacts in the final stack. Then I tried again with 12% of 300 subs and got a better result. Colour, saturation, curves and unsharp mask sharpening in PixInsight.

Moon 251123_02_P12_PI_EL.jpg

Graeme

[stuck]

That's a good shot!

Ken

[Graeme]

Ta! It's clear again tonight, I'll see if I can get the other side!

Graeme

[ChrisGreaves]

I set the telescope to Lunar tracking rate and captured 1000 x 0.003 second images. I tried stacking 980 frames in AS3 a number of times with various settings but kept getting strange blocky stacking artifacts in the final stack.

Graeme, what he said. But also ...
You do two things with images:-
(1) you set up the hardware (camera, tracking scope etc.) and trigger the action to harvest data.
(2) you process the data, choosing which images, and what techniques to apply.

Q1: Is there anything in this work that could NOT be done by two individuals using limited feedback? ("next time try 400 frames in AS4 ....")
alternatively
Q2: Is there anything in this work that inhibits you taking images on (say) Monday, but postponing the data processing until (say) Saturday.

Obviously once the eclipse/osculation has been photographed (image data collected) the eclipse is over, so feedback is somewhat useless.
But supposing images of a stable sight (the Pole star, Orion, the Greaves galaxy etc.) is there a solid reason inhibiting splitting the process with image data collection in Chile (clear skies) and data processing in the UK (cloudy sky).

I have read blogs (by Dr. Becky, I think) where the astronomer sits at home, having set up their trials by a one-time installation trip to to Chile; but how about Graeme?

Cheers, Chris

[BobH]

Ta! It's clear again tonight, I'll see if I can get the other side!

Graeme

[Graeme]

Q1 - Using the same data then no I suppose. Would you like a link to my lunar data to have a go at stacking it or processing it? As for splitting the data geographically, do you mean the capture or the processing? Either way, no not really. A number of people using a number of telescopes could collect data and all have a go at processing it all separately.

Q2 - No, you can store up the data for as long as you like. My Pickering's Triangle was captured over three separate nights and processed a week later. However, unfortunately, hard drive capacity is finite so eventually stuff has to be deleted.

Graeme

[ChrisGreaves]

Q1 - Using the same data then no I suppose. Would you like a link to my lunar data to have a go at stacking it or processing it? As for splitting the data geographically, do you mean the capture or the processing? Either way, no not really. A number of people using a number of telescopes could collect data and all have a go at processing it all separately.

Graeme, thanks for these replies. Most of the time I'm not sure what I am asking, just that I have a weird mental "itch" that needs to be scratched, and an insatiable curiosity. I glance from my study window and see the moon low in my Western sky; It's the same moon ...

The only use I can see for your lunar data would be an excellent and inexhaustible supply of random data for a pseudo-random number generator. I could have used that mass of data a long time ago!

"As for splitting the data" I think I meant delaying the the processing⁽¹⁾; I reason that the data you capture and the data your pal one hundred yards down the street captures would be two different sets of data. The individual photons strike the retina independently and randomly, correct?

In that sense I was thinking of your schedule and allotment of time. If you had two glorious events on successive nights, you could devote your time to setting up the hardware and do the data processing at a later time.
If your pal's computing system was commandeered for doing this year's tax returns, I suppose that you could process your pal's data on your computer.

Q2 - No, you can store up the data for as long as you like. My Pickering's Triangle was captured over three separate nights and processed a week later. However, unfortunately, hard drive capacity is finite so eventually stuff has to be deleted.

I think I am supposed to reply that nowadays disk and tape storage is cheap, but I know that it is cheap in a relative sense to 10, 20, 30 years ago. We are all on limited budgets.
If you know any Aussies using Australia's telcom "Optus", well, Optus are offering free storage capacity for a little while(grin)

So your current storage capacity roughly defines your current latency time in terms of how many sightings you can buffer up before you absolutely have to process the backlog.

⁽¹⁾ I see how now how silly this all sounds. Obviously you wait until the event has passed and all the necessary data has been captured before you can start data processing.

Thanks, as always, for my education from your elucidation.
Cheers, Chris