Here is my first thoughts written down. Probably needs some rewriting, as most of my writings go.
Date Quick Summary
March 8, 2013 Big Setup Panstars 8 degrees above sun, could not see the
comet from Allen Park. (10 inch Newtonian, BT-80 and two
four inch refractors were setup.)
About six FAAC members showed up.
We had a good time and observed other objects
Haze low clouds up to 5 degrees prevented observation of
the comet.
March 13, 2013 Was able to see the comet from Allen Park location.
Comet was relatively bright at 1 magnitude.
20 -25 people visited. Rick Arzadon and James French
were there as well.
March 14, 2013 (Math night at LP Middle school.) I did Allen Park observing
Gorden Hanson found the comet first with 10 by 50 binoculars.
20 people including visitors.
Saw comet, Imaged with Nexstar 4SE at 42x with fixed mount
Brian Kutscher showed up and took images using C8.
Greg Ozimek showed up with his camera.
Comet looked nice in 10 inch Dobsonian Rick Arzadon had.
In Lincoln Park, four FAAC members saw it in 10 by 50 binoculars.
March 17, 2013 Saw the comet at dark sky site with Ken Anderson, Island Lake
Ken had three binoculars, I deployed the BT-80 binoculars.
Ken wrote a good observing diary. (Mag 1.7 comet.)
Comets tail was short, but bright. Ken saw comet naked eye.
Comet Tail as bright as the M42 nebula in my BT-80’s
Ken Anderson found the comet first with 15 by 63 binoculars.
March 22, 2013 Saw it in Allen Park with Ken Anderson.
Used laptop imaging with Canon to locate the comet in Allen Park.
Comet was dim at Magnitude 2.8 with sky glow and haze.
FAAC Astronomers showed up at HJRO as well,
some saw the comet through the C14 and Meade.
March 23, 2013 Realized sky would be clear late in the afternoon.
Could not drive out to meet Ken Anderson in time.
Stopped at Belleville Lake, which was not a good site.
Could not locate comet with laptop images or binoculars.
Clouds moved in as comet set cutting other observing short.
Park had to much street and traffic lights.
The format of this blog text above is a little messed up. Copying and pasting the stuff inside the browser after having it in Pages may have some odd side effects.
I don't know if I'm going to post a photo from yesterday.
I didn't try to look at the comet from Allen Park. Dan texted me and asked me if I would be trying to view it from here. I decided to try to view Panstarrs from a darker site, but I was running late. I could have setup in Allen Park, but I was afraid I'd get results about the same as the day before. Look at the photo below. You can see. . . perhaps on the expanded photo of this . . . how small the comet was looking in the night sky Friday night.
I talked with George on the way out, realizing that I didn't have enough time to meet Ken Anderson at a darker sky location. I wondered if there was something better, with a low horizon than Allen Park, with less lights.
I thought about Ford Lake, overlooking the lake toward the Raddison on the Lake, from Grove Road. There is a lookout point there, but access for unloading would be difficult, a lot of walking.
George said, just go to Allen park, the comet should be nice from there with less haze according to what he was seeing and reading.
I decided to try this other site. I wish I had the time to make it out to view it with Ken Anderson out near Island Lake. He was at a better site.
I decided to stop at Belleville Lake, as I used to hang out there a little bit and at least eat something at the restaurant on the Lake there. I setup at the park, easy car access to the park.
The parking lot had to many trees, and that would seem to be a problem also there are ramps there, but the ramps might not be as stable for viewing at higher powers.
I ended up setting up out there, but soon found out that was not a good choice.
The problem with the park is there are lights right in the park. Because that park is on the street we have car traffic going up and down and headlights can shine on you and your telescope. We are looking away from the lights, but we are looking over sky glow in the distance from Ypsilanti and Ann Arbor. This gives a light dome that is pretty bad. The lights across the lake will of course hit your optics. You have a lake, but the pretty things you see like lights reflecting off the water, may also cause other problems like lens flares, which could muddy up your image. So Belleville Lake is not a good place to view Panstarrs from, especially as it's a dimmer object.
Well my post has started to wander off on a couple of tangents. Let's get back to the photo below:
This was shot at 1600 ISO in manual mode. Aimed at and focused on the moon before shooting this.
Using "live view and zooming in with the live view at 5x and then 10x digital power, you can focus the stock lens on the Canon T1i pretty easily.
The F stop was higher, giving a smaller apeture opening and a greater depth of field. This is what we want, more stars in focus and a nice deep depth of field doesn't hurt for night time astrophotography. I'm basically getting a wide landscape shot, not a shot of an object like it's a fashion model. With a wide F stop or greater opening on the lens, like F5.6 or lower settings. The depth of field would be more shallow and you would select what is in focus and want objects behind and in front of your subject out of focus. In Astronomy we want more stuff in focus, being out of focus isn't good. We'd lose the details. With a higher F stop we might need a longer exposure. Bad for the comet.
But in this case the sky was bright and I actually adjusted the photo to make it a little more dim to bring the edge of the glowing night sky up to the approximate place of the comet in the sky.
I think putting the comet just above a brighter patch of sky but in a darker part of the sky gradient is a good thing, from an artistic point of view. The sky is glowing and brighter at the horizon, we know that. A brighter exposure will cause more of the sky glow to flow up higher and wash out the sky.
I can try to expose it to match what we see as humans, in the post or try to match the sky up to give the best artistic and details from the comet that is possible. We could in a sense argue back and forth saying, you should be true and give the exposure a true to life setting, but in Astronomy we are trying to see fainter stuff. So we will often try to bring out those details, by pushing the exposure or taking longer exposures to show fainter objects.
In the case of Panstarrs at that time: 8:40PM the sky was still apparently bright enough on digital film with a 3.2 second exposure. So we have a brighter than human eye feel to the shot. And to get more detail you actually have to make the photo darker with your simple processing trick.
(Sorry of this post is quite long and seems to be repeating. I'm really tired as I'm writing this, so it might not make a lot of sense and I may have to rewrite this.
Here's the photo from Friday. This from Allen Park.
We didn't even find the comet that night in Ken's big 16.5 inch dobsonian telescope.
The photo above if enlarged by clicking on it will show you the comet as a faint object near the right side of the screen. There is a bright star which was actually 8 degrees to the right of the comet and that should be seen as well in the photo. As you can see I'm partially transparent in this photo, becaus
You'll need to click on the photo to see the larger photo in order to see the comet.
As you can tell from this simple processing of this basic photo, Panstarrs has lost a lot of it's brightness. It's magnitude 2.8 in this photo according to Sky Safari. That's about six times dimmer than when we first saw it.
The sky glow at Belleville was in some ways just as bad and the horizon wasn't as good as at Allen Park.
For the Saturday quick viewing trip, I found that clouds were quickly covering the lake as the comet was falling below the horizon.
When I returned to Lincoln Park, the sky was covered with clouds. This at about 10PM. Later the sky cleared up, but it was cloudy for quite some time. Way out in other areas, like Novi or I275 and 7 mile road for example, the sky wasn't as cloudy. Astronomers out that way were still observing while we had overcast skies.
(Tomorrow when I read this blog, I'll likely be kicking myself for not having planned and written this post better.)
Greg
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