Anyone know why there is absolutely no trace of the above nebula on any
one sub, or the final stacked image of my attempt. I Know it is faint, but other people have recorded it using similar equipment and settings.
Mine was 6x 100 secs, @f/2.8, ISO 1600, sky Bortle 3, target close to Zenith.
raymo
I'm suprised you could't resolve even the very slightest trace of this reflection neb. I had my doubts too when I had a go of this last year as a first attempt(actually second - the first time had the perfect site at Lake Tyres, Vic coast and stuffed it up - bad polar alignment with too many stars to pick from confusing me with Octans shape)
I snapped this at Steels Creek using a Canon Telephoto 90-300 Lens.
Sky that night was clear but Orion was setting well over to the west and not the best position given Melbourne's skyglow just in sight blurring it out. None the less with heaps of shots managed to get something to show up.
It should be easy enough to frame with bright Rigel helping with your pointing. Try and re-shoot it with Rigel in the frame - you should get her.
PS I used high ISO to resolve it. All stuff I'm sure you already know of course...
I raise you a horse head with my first attempt at a mosaic. Here's my impression of the horse head where it should have been after a few hours of deep exposures on the hyperstar and more than a few crownies. The real horse head was in fact hidding just off field in the direction of the arrow. B|tch...
Hi Lewis, I know it was in the field, although it would have been fairly small,
as I was using a 100mm lens which covered from the belt stars out to well beyond Rigel, in fact well beyond Beta Eridani. I'll try at 200mm next clear night.
Hi Marc, I have also missed targets, but not this time. Nice shot, amazing amount of "stuff" in that area.
raymo
Last edited by raymo; 25-10-2018 at 02:17 PM.
Reason: more text
Anyone know why there is absolutely no trace of the above nebula on any
one sub, or the final stacked image of my attempt. I Know it is faint, but other people have recorded it using similar equipment and settings.
Mine was 6x 100 secs, @f/2.8, ISO 1600, sky Bortle 3, target close to Zenith.
raymo
Raymo,
You probably need to stretch the data by increasing the brightness of the fainter data in you image. Posting a sample may allow someone to determine what has been captured.
Hi Paul, I'm not at home at the moment, and almost all my astro stuff is
on one of my other laptops. I'll see what I can do when I get home, if
anyone is still interested by then.
raymo
Anyone know why there is absolutely no trace of the above nebula on any
one sub, or the final stacked image of my attempt. I Know it is faint, but other people have recorded it using similar equipment and settings.
Mine was 6x 100 secs, @f/2.8, ISO 1600, sky Bortle 3, target close to Zenith.
raymo
Raymo, my concern is you weren't targeting the right area of the sky. If you were close to the Zenith at the time, then you were too high up. Rigel reaches it's highest point at about midnight around December the 21st when it's about 60° above the horizon, that's a fair bit short of 90°. Have another go, the good thing is, that witch ain't going anywhere!
I just meant that it was high in the sky, well away from interference from
street lights etc: I know exactly where it is, down to the two faint stars that mark one end of the Witch. It puzzles me because I have 50mm shots of the
whole of the area that extend well beyond the Witch, that show quite a lot
of the red that permeates the area between Rigel and the belt stars, but not
a trace of the Witch.
raymo.
Here is an example: 5x100 secs f/2.8 ISO 1600. No matter how much I play with it, I can't see a trace of the witch. My eyes are
over 80 yrs old though.
raymo
Last edited by raymo; 27-10-2018 at 10:40 PM.
Reason: more text
Yes, I could see it too. Mind you, only just and only because I know where it is and what it looks like. Two reasons why it may not have shown up well on this shot: 1. It's right at the edge of the frame so would be suffering from lens aberrations, thus losing contrast and resolution. 2. This shot ( which is a nice shot by the way ) seems to be affected by either dew on the lens or very high cirrus cloud perhaps. The bright stars look very diffuse, which usually is a result of this. This would not favour a faint nebula such as the Witch Head.
Thanks for taking the time to have a look at it fellas. I shall do it again
with a longer lens, and longer subs if I get my alignment consistent on my nano tracker.
raymo
