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Old 08-03-2021, 02:29 PM
evltoy (Wayne)
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evltoy is offline
 
Join Date: Sep 2020
Location: Melbourne
Posts: 81
the eggy stars continue!

Hey Guys,

Once again thanks for all your experiences & knowledge in helping me out.

I'm currently still on the south coast and it has been kind to me with no rain since I have been up here. With this, I have been able to leave my neq6 + 8" SCT/ED80 out (covered) for most of my stay. I have also managed to use the Park feature which works 100%... what a time saver!

OK. so based on everyone's feedback here and what I have read here is what I have done.
1- Mark up mount; Home location, RA, Dec clutch etc.
2- Rough polar align Tripod (south)
3- Level tripod with a builders spirit level on solid ground
4- Place head on tripod and balance in both Dec & RA with OTA + gear
5- Set up clocks in both Dec & RA
6- Give a little eastward heavy by adjusting weights (lower)
7- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel)..
8- Polar Align on Sirius (through DSLR finder, centered) very close
9- Turn off mount

10- Reset clocks & turn on mount
11- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel).. very little adjustments
12- Polar Align on Sirius (through DSLR finder, centered) Bang on centered!
13- Turn off mount

14- Reset clocks & turn on mount
15- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel).. spot on, no adjustments
16- Polar Align on Sirius (through DSLR finder, centered) no adjustments required
17- Using the Park feature from here on after end of session

My Polar Alignment Error readings are “Mel=+000,00’00" Maz=+000,00’05”

My guiding through PHD2 is default settings with letting PHD2 selecting a guide star (SNR was 4 or 5ish) and total error was around .30-.40 (running for 3-4mins) before shooting.

Some said to check my back focus spacing as the eggy stars were in different directions on the outer sides of my frame. From no spacing (using the Celestron reducer + T-Adaptor and T-ring) to putting a 5mm spacer I saw no difference. And here is an image I did last night with a 10mm spacer.

I selected the best 33 images in DSS and the exposure time was only 90sec per sub

Can anyone provide some direction on why my stars are the way they are on the edges?

Cheers
Wayne
Attached Thumbnails
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