Comet C/2014 Q2 (Lovejoy)

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The latest in the series of Lovejoy comets is putting on an impressive display. It’s just west of Orion right now, and tripod shots with even short exposures catch it pretty easily. This is a 10 second shot at 55 mm f/4.0 ISO3200. (images link to larger versions)



After that, I set my T3i up on an equatorial mount with rough polar alignment. The 55-250 mm lens zoomed all the way in start showing some structure in the ion tail with just 30 second exposures at f/5.6, ISO 3200. This is a stack of 10 exposures aligned to the comet, so there is trailing in the star field. I need a better grasp on applying flat frames, so the field is pretty uneven. But you can just make out an interesting disruption in the tail, close to the center of the frame.



It’s a nice sight through binoculars too, with a subtle turquoise color and from my location, about 2 degrees of the ion tail emerging from the large coma.

Anyway, thought I’d start this thread in case anyone else has or will be photographing it—
 
Sep 7, 2013
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Very impressive!

Having just moved out into the country, I've had a great time watching meteor showers this year, geminids were spectacular this year, I'll have to get out the camera and telescope and track this sucker down. Been too overcast lately.
 
Mar 6, 2006
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If the clouds break tonight like forecasted, I will try to grab a shot or two of it. Had clear skies the other night, but couldnt bring myself to get out in the cold, during the work week at least.
 
Aug 16, 2009
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I tried my hand at shooting the comet. It was tough to find but I just swooped up and to the right of Rigel and found it. For now it just appeared as a greenish fuzzy dot. Maybe tomorrow (weather permitting) I'll get out of town early enough to see it before the moon rises. I'll have my hand at some stacking too. This is a single pic I took with my T2i using my Sigma 55-200mm zoomed all the way in. This is also my first real astronomy picture I've taken.

 
Aug 16, 2009
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John I was out around midnight. The only problem is the moon made for a lot of light noise. It's probably best to get it just after twilight before the moon fully rises. Look for Orion's belt and Rigel. Should be to the right by about 20 degrees.
 
Marcus, nice catch—it looks like there may actually be a hint of the tail starting to show in the green channel pointing to about 11-o'clock. Away from the light pollution and frustrations of the Moon, it'll probably start holding its own.

When I went out and shot it last night, the tail did seem a lot fainter than the day before, but I think that's because it was more fanned out and with lots of streamers in it. It's pretty interesting that it's changing so much each day.

John, like Marcus said, it's in good position high in the southeast right after it gets dark after sundown. Also, you can have a look at Sky and Telescope's page—they do a nice job on their finder charts: How to See Comet Lovejoy Tonight.
 
This is from a set of three 3-minute exposures at ISO3200, f/5.6, 250 mm, tracked on an equatorial mount. I wanted to get a few more, but the Moon crested the horizon and started washing things out before I could. The comet's motion over each three minute exposure did smear and soften the tail, but some of the structure still came out. I processed the image so that only one set of stars showed this time.

 
Aug 16, 2009
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This equatorial mount you speak of. I feel like it's very necessary for astronomy pics. I couldn't go more than 6 sec exposures before things began to streak and smear. I think the windy night is going to hurt me today. Might have to try tomorrow night when it's not so windy and a little warmer.
 
This equatorial mount you speak of. I feel like it's very necessary for astronomy pics. I couldn't go more than 6 sec exposures before things began to streak and smear. I think the windy night is going to hurt me today. Might have to try tomorrow night when it's not so windy and a little warmer.
From what ive been told they are a must. But ive also been told you if you have a telescope, you can piggy-back it with your lens and be ok. But im not 100% sure if that actually works or not, maybe Jeremy can chime in on that. I do know that equatorial mounts are pretty darn expensive.
 
Yeah, star trailing gets to be an issue with tighter zoom. I missed that you were shooting 200 mm on that first one. If you back the Sigma out all the way to 55 mm you might be able to triple your exposure time though. The tradeoff of smaller scale may be worth the added exposure.

There is this astrophotography guideline for tripod shots called the 500 rule. Divide 500 by your focal length and that's how long you can expose on a tripod before star trails become evident. If you can live with a little bit of trailing, you can fudge that more—but it gives an idea. If you don't mind a little bit of trailing like in the first 6-second shot, then you could go with a 1200 rule (1200/200 mm = 6 seconds). So at 55 mm: 1200/55 = 22 seconds. At 55 mm, you'd also be able to open it up to f/4 for more light.

If you decide to try stacking multiple images, that can help overcome short exposures by buying more signal to noise in the composite image. That does add to the time investment.

High magnification astrophotography is a huge processing pain & really time consuming (at least to me it is every time I try it). So I usually stick to wide field shots to improve enjoyment levels.
 
Aug 16, 2009
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Thanks Jeremy for those tips. I'll give that a try. I was going to attempt stacking too but not sure if you can do that in Lightroom (I'm sure there is just haven't looked). One incentive to working at my job so long is a free gift from a catalog. One of them was a nice beginner's telescope. Didn't know if I could combine that with my camera to get some zoomed in pics of planets and possibly comets.
 
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.
 
Aug 16, 2009
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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.
 
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.
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.
 

Jeff Duda

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Oct 7, 2008
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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.


Comet pretty evident at the center of this photo.


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.