5th or 6th attempt on the great Orion Nebula

[Kevin Phillips]

I think this is the best yet. I am sure in the future I 9will be able to do better.  

80 frames at 3 min exposures. 

40 of each flat, dark flat and darks.

Heq5 mount 

714 mm duplet refractor Horizon refractor 

Zwoasi294 plus L pro optilong filter

 Guided. 

Sent from Outlook for Android

[James Mallett]

This is such a great photo, thanks for sharing it.  

I am new to astronomy and over the past few months I've been exploring the sky with a pair of celestron skymaster 20x80 binoculars. A few days ago from my garden in Purley I was scanning the sky with them and noticed a couple of stars that looked like they were blue headlights in fog just under the area of Orion's belt. It looked great and so different from anything I've seen through the binoculars. When I came in later and looked it up on a star map I realised that this was the Orion Nebula so to see the picture you've taken is brilliant! 

Thanks again :-) 

James 

[Kevin Phillips]

You are so welcome. Thank you for your kind comments.

Kevin

Sent from Outlook for Android

---

From: croydo...@googlegroups.com <croydo...@googlegroups.com> on behalf of James Mallett <jmallet...@gmail.com>
Sent: Sunday, January 12, 2025 12:09:10 PM
To: croydonastro <croydo...@googlegroups.com>
Subject: [croydonastro - 8020] Re: 5th or 6th attempt on the great Orion Nebula

 

--
You received this message because you are subscribed to the Google Groups "croydonastro" group.
To unsubscribe from this group and stop receiving emails from it, send an email to croydonastro...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/croydonastro/7319612d-5060-4b0a-abdc-41d8d541c569n%40googlegroups.com.

[William Bottaci]

Hello Kevin
Yes, nice image, and I think it is your best so far, particularly in that you have more tones and better control of the exposure. Surprising it's just the one exposure setting. Stars are small and tight, as you usually do now.

An explanation for others, hopefully helpful:
 - the Optolong L-Pro is a broadband filter mostly for light pollution. Broadband meaning it's not precise but is a lot cheaper, certainly better than nothing, and narrowband is best for mono cameras. This lets through the main nebula emission lights of OIII, H-beta, SII, and H-alpha and does its best to exclude the usual suspects of streetlights, though that is changing for the worse, but overall better to use this filter than not.

 - The reason for taking many identical exposers is to reduce the noise introduced by the electronics of the camera, and the flat, dark flat, and darks also help reduce noise. The image would look a lot worse without these.

 - Welcome to the group James. 20x80 binoculars are great on this nebula, though when looking visually a darker sky helps more than when imaging. Sweeping the Milky Way I'd say better with binoculars than a telescope.

 - Kevin, I know you're going to swap gears for a belt for your HEQ5 mount, and as John says the Rowan belt mod is good because it removes backlash that you get with gears. Only really worth doing if you're guiding because of the many tiny correction movements. Shame it's an expensive job.

Thank you for sharing.
William

On Sun, 12 Jan 2025 at 18:09, Kevin Phillips <Thewelsha...@hotmail.com> wrote:
You are so welcome. Thank you for your kind comments.
Kevin

On Sun, 12 Jan 2025 at 03:25, John Mills <ellism...@gmail.com> wrote:
Hi Kevin,
That's a great image! Nice round stars. I see you're using an EQ5 mount.
I have 3 x EQ6 mounts here. Two I hire out for visiting UK amateur astronomers and the other I use. The night sky here is one of the best in the world with the "seeing" often below 1 arc sec.

I still have to do the Rowan belt mod which eliminates backlash in the spurs gears between the worm wheel and the motor. I found that doing plate solves (more so when the telescope moves off to refocus) that there was lost motion when the scope returned to the target. Taking out the spur gears eliminates most of that.

The EQ5/6 mounts are very good. There's a Rowan belt mod for the EQ5 mount which is a lot easier to install than the EQ6 which requires a major strip down! The Rowan belt mod is Well worth doing if you haven't done this. Here's the URL:
https://www.firstlightoptics.com/astronomy-mount-upgrade-kits/rowan-astronomy-sky-watcher-heq5-pro-orion-sirius-eq-g-belt-mod-kit.html

ATB John M (La Palma, Canary Islands)

On Sun, 12 Jan 2025 at 12:12, James Mallett <jmallet...@gmail.com> wrote:
This is such a great photo, thanks for sharing it.  
I am new to astronomy and over the past few months I've been exploring the sky with a pair of celestron skymaster 20x80 binoculars. A few days ago from my garden in Purley I was scanning the sky with them and noticed a couple of stars that looked like they were blue headlights in fog just under the area of Orion's belt. It looked great and so different from anything I've seen through the binoculars. When I came in later and looked it up on a star map I realised that this was the Orion Nebula so to see the picture you've taken is brilliant!
Thanks again :-)
James