View Full Version here: : Sun today - First Light with my PST
09-04-2010, 12:47 PM
Today I finally got to capture my (second) first light with my PST. I used my DMK21AU04 with the lens of a Meade 140 2x barlow screwed into the DMK nosepiece to allow it come to focus.
I haven't had a chance to grind down the nosepiece to allow it to come to focus at prime focus.
I also tried my DMK41AF02, and while I could get it to work at 3.75fps, it wouldn't work at 7.5 or 15fps. Need to figure out what's going on there.
There's a little activity on the Sun today, a few proms and filaments and an active region too.
Finding the right exposure for the surface and the proms is difficult, and the PST does have that "hot spot" with a much brighter area than other areas. Trying to flatten that out during processing is a challenge but it doesn't look too bad now.
Only my first attempt at processing solar H-a images, and trying to balance the sharpness, contrast, colour, whether to have the "glow" on the proms exposure etc, is all trial and error and personal preference.
I chose to have the "glow" still visible as I felt it gave the sun a bit more "presence". I might change my mind next time.
Anyway here's the images. The second one is an inverted version of the first.
Thanks for looking. It's nice to be able to post something again. Comments and suggestions welcome.
09-04-2010, 12:52 PM
nice prom on the bottom, i still have to find the time to use my Lunt - you are a luck bloke mike ;) all this "free " time
09-04-2010, 01:11 PM
Very nice Sunnage? Solage? (did we ever decide what to call it??) Mike.
But doesn't it get hot out there looking at the sun.
I was out the other day taking a few snaps through the ed80, I nearly melted.
09-04-2010, 02:21 PM
Goodness Gracious! Great Ball of Fire!
No need to worry about dew heating or mossies! Might be a good move, Mike!
09-04-2010, 02:39 PM
Nice work Mike - that big area - top left of image 1 - was interesting - a big ugly smudge on the Sun - is it a filament (seems to broad?) - it is the largest non descript Solar thing I have seen.
09-04-2010, 03:41 PM
Nice work Mike – glad to see you outdoors under the (daylight) skies enjoying yourself!
Yes, what is the bow tie shaped thing?
Beautiful photo's Mike.
09-04-2010, 04:05 PM
It's on image 2 also. Dust bunny?
09-04-2010, 06:35 PM
Great start Mike!:thumbsup: Did you capture the surface detail and the proms in one shot or have you done a HDR blend? Very smooth either way!
Nice pictures Mike. I hope you sort your DMK41AF02 camera issues out.
09-04-2010, 08:38 PM
The big smudge - Quiescent Prominence (Filament) -- Long, sheet-like prominences nearly vertical to the solar surface.
09-04-2010, 09:24 PM
Great images Mike, the inverted one is awesome :)
And yes that big spot at the top of image 1 and 2 certainly look mysterious, I wonder what it is.
09-04-2010, 09:42 PM
years after getting my pst i have yet to get one decent image out of it!
10-04-2010, 09:56 AM
Nice images. I am no expert, but I think sometimes glow looks good and sometimes its better without. I too think it often gives a more powerful look. Also I recon solar imaging is about what looks cool... yes there are those that do prefer it to be technically accurate, etc but I just like the pretty pictures and when you get one that has the Wow factor :-)
Ummm ... scope in the sun, you in the shade ;)
10-04-2010, 12:23 PM
Excellent Sunnage Mr Solway.
Cheers Petra d.
11-04-2010, 12:27 PM
welcome to the Sun Mike! Loads happening in each image.
To clear the pst "hot spot"
- apply a curves adjustment-layer and pull down the curve the required amount.
- Now "ALT click" on the mask of the curves layer (the white icon to the right)
- fill the mask with black (use the paint bucket) to hide the effect of the curves
- "ALT click" again to see the image
- now select the paint brush tool and make its colour white and "paint in" the curves effect in the hot spot
- changing the opacity adjusts the amount of the curves effect
Now unfortunately that PST looks like it may be astigmatic as the image seems a bit soft. The prism in the focusing mechanism is held on by whats effectively "pritstick glue" so goes out of alignment easily. Theres info on the www on how to fix it. best test is to use as high a power as the seeing will take and see if the image will "snap" into focus (as they do with your top quality planetary images!).
Hope this helps
12-04-2010, 07:18 AM
Thanks to everyone for your comments and feedback. Much appreciated. It's certainly nice to be able to post some astrophotography again.
I held off getting a PST for a long time because I simply DON'T have free time during the day to use it! :) I'm at work (or in transit) for 12+ hours a day, so it only leaves weekends, which is difficult because of family commitments etc.
I was fortunate enough to get some time on Friday morning because I was working from home that day :)
Thanks Matt. I was intrigued by that broad area too - I'm pretty sure it's just a big filament but on a strange angle we don't normally see.
Thanks Dennis. It was a different experience. Quite quick and easy to setup too, which is a bonus.
Definitely not a dust bunny - I think it's a broad filament on a strange angle. Image 2 is just an inverted image 1 :)
Thanks Al. They are 2 separate exposures processed separately and blended in PS. I used about 1/20th sec (15fps) for the proms and about 1/180s (30fps) for the surface. I found during processing that some of the proms were captured even using the surface exposure - so I'll try experimenting more with the exposure and frame rate and perhaps reduce the double processing I have to do.
Thanks Troy - the DMK41F issue is really annoying. I just wish I could swap the bloody thing for a USB version.
Thanks Narayan. Apart from focus and composition, a lot of work seems to be needed in processing to ensure a nice looking image that's not overprocessed. It can be very easy to overprocess solar images I've found.
Yeh i'm not sure about technical accuracy either, but for now i'm just happy to get some nice looking pictures and will work on the rest later :)
Yes - that's what I found too. It was too hot sitting in the Sun, and I couldn't see the laptop screen to focus properly or to see if the exposure was correct.
Given a lack of hutch or observatory, my unique solution was to drag the kids trampoline right next to my mount, so I was sitting on the ground with my laptop under the shade of the trampoline. I could still reach the PST to focus it, had the hand controller next to me for composition.
So I was in the shade and it was much more comfortable :) Apart from having to sit on the ground, that is.
Thanks Dave. I reduced the hot spot somewhat but there's definitely more I could do. I was trying to find out how to create an artificial flat frame, which would even the exposure across the image. Haven't got it nailed yet but will keep practising.
I'm not sure about astigmatism. The softness could be a result of the seeing or the focus. I really didn't take the time or care needed to ensure sharp focus, and I probably stacked too many frames.
I'll definitely keep an eye on it for next time and see if it improves.
Cheers and thanks.
13-04-2010, 09:15 AM
Ah welcome to solar imaging. Now you are gonna find out what seeing really is all about. Hehehehe;)
I would check it for astigmatism as this is what I thought too. When imaging you should be able to see the fine filaments on the video in reasonable seeing. If not you most likely have some astigmatism in the scope and like Dave said it is fixable.
Might I suggest you download a copy of Avistack and use this for solar processing. It works better than RS for solar work and for lunar too.
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