Comet C/2014 Q2 (Lovejoy)

Marc, I was thinking about those too—they seem like a good option. One that I had browsed recently was iOptron, but I know there are others. It seems like $300 is the basic starting point.

The telescope mount I'm using runs about $360 these days, but really bulky if it was just going to be used as a DSLR mount. It works ok for wide field tracking, and seems to do ok with the 250 mm lens. But it's terrible for shooting long exposures through the scope itself—just isn't accurate enough at those magnifications. Getting an equatorial mount suitable for that kind of work gets pricey in a hurry—it's definitely been a stopping point for me.
 
Ok so I went out and took several pics using 2 different lenses. I used those equations Jeremy and my pics already look much better. Now I want to stack them. Any suggestions on programs?
 
I have just started to dabble in astrophotography and just recently I purchased an iOptron Sky Tracker for DSLR cameras. I actually bought it for getting decent images of Lovejoy. It took a while to get the technique right to get the results I wanted, not too bad for no telescope. This was captured with 60sec x24 exposures, f/8 ISO: 1000 on my Nikon D800 with my Sigma 400mm f/5.6. They were then stacked with Deep Sky Stacker converted to TIFF and processed in Adobe Photoshop CS2. The only problem is not I want a telescope! Oh well, at least it gives me something to do during the drought.

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That caught a really distinct split in the tail, Ben—very cool to see. It's kind of nice to have amateur astronomy to fall back on outside of chase season...or during crappy portions of chase season.

One thing I've been trying to improve is dealing with vignetting—which becomes extreme in astrophotography due to how much the images are stretched. If you decide to tackle that one, check out sites discussing flat field/flat frames. I'm pretty far from perfecting the process, but it's helped even out the frame somewhat...when I take the time to apply it.
 
Jeremy Perez said:
That caught a really distinct split in the tail, Ben—very cool to see. It's kind of nice to have amateur astronomy to fall back on outside of chase season...or during crappy portions of chase season.

One thing I've been trying to improve is dealing with vignetting—which becomes extreme in astrophotography due to how much the images are stretched. If you decide to tackle that one, check out sites discussing flat field/flat frames. I'm pretty far from perfecting the process, but it's helped even out the frame somewhat...when I take the time to apply it.
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Thank you, Jeremy. Yea its been a lot of fun trying out this type of photography. I thought about doing the flat frames, but by the time the 1hr mark came around I was ready to back inside and out of the wind, lol. When it stats warming up I'll try the flat frames. I've heard to use a white object like a t-shirt or something, I was planning to use a cheap white balance cap so I don't have to worry about holding anything.
 
Yeah, as much time as setup, imaging, and processing already takes, doing flat field work for a more casual project really feels like a chore. I've tried short-cutting by using lens correction in Lightroom/RAW module—that helps a little, the gradient is less steep, but then it takes the form of a bullseye, which I think is even worse.

I used the tee-shirt method, making sure the aperture, focal length, and focus (∞) were the same as the original exposures. Then held a couple layers of tee-shirt to the lens and shot a dozen images of the sky in different directions, then averaged together into a master flat frame where the peak of the histogram is roughly centered. It's kind of magical to set that layer to 'divide' blend mode and watch the image even out.

That white balance cap sounds like a better option—I'll have to give that a look. One thing nice about shooting straight from the camera is the ease of shooting the flats whenever you want. As soon as a telescope gets involved, then you have to make sure the entire optical train is in the exact same orientation as the shots were taken, so no great options for shooting those another day.
 
I learned the hard way this past weekend just how difficult it is to see this damned comet. I could not see it with the naked eye even way out in the country (the Wichita Mountains Wildlife Refuge near Lawton, OK). It was also very difficult to photograph. The only way I could even tell the comet was in my photos was to compare shots on two consecutive nights and notice that a faint teal speck moved relative to the stars around it.

I was shooting with a Nikon D40 with various settings. Generally used f/5.6 with ISO of anything (200, 400, 800, 1600, and "HI-1" - whatever that means) with varying exposure lengths from a few seconds to 2 minutes or longer. Definitely had the streaking problem Marcus mentioned. I also had issues keeping the image focused, as I had to basically point my camera straight up and kneel on the ground to focus, and that was difficult for me. My 18-55 mm kit lens does not have an infinity focus mark anywhere, and the actual location on the focus ring seems to change all the time.

I hadn't read through this thread before attempting the photography. After skimming through the posts, I can see why I had such a hard time getting any shot at all.
 
I managed to get a couple pictures the evening of the 15th. No visible tail, but at least the comet is recognizable. It is very dark in our wooded, semi-rural neighborhoods on the outskirts of Pagosa Springs, CO, so that helps.

Lovejoy1.jpg

Comet pretty evident at the center of this photo.

Lovejoy2.jpg

Comet (lower right) with the Pleiades (upper left)

Both of these were 10-11 seconds, F-4, ISO 1600, 70 mm.

I might add that although I first saw the comet on the 11th, my attempts to photograph it that night were epic fail. But upping the ISO to 1600 on my second attempt on the 15th did the trick.
 
Thanks for the likes guys. The previous shot was mostly of the comet head. Here is one of the whole comet including as much of the tail as I could get. We worked with the water vapor satellite chasing the driest air for a clear window into the sky. Also I went after the best "Bortle sky" I could get. Bortle is a scale of darkness. The darkest Bortle skies in the US are at Big Bend National Park in south Texas so that's were we shot this one. No telescope here, just a Canon camera and a Canon 400 mm F 5.6L lens. This shot was tracked for 5 minutes. The next comet will be Catalina and it will be arriving late summer and early fall of this year.lovejoy q2 big bend-1.jpg
 
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