Comet Tsuchinshan-ATLAS may become a naked-eye object soon.
Best viewing is likely to be the 2nd week in October, when it will be an evening object, hopefully visible just after sunset, close to the sun:
You may also have a partial lunar eclipse tonight.
I have cloudy skies. 
My APP shows it passing close to the M5 globular cluster on 10/15, current predictions of similar brightness which could be really cool.
No sirree. I was Kohouteked once already.
I’ll do it for you.
You didn’t miss much (probably). I live in the northern suburbs of Chicago. Here the maximum occultation was MAYBE 10% at the top.
OK, the comet is up, starting tomorrow just after sunset.
Looks like it will be pretty good for a few days, and then start to fade away.
It’s closest to Earth tomorrow, but will only be visible for an hour or so after sunset. Sunday might be the best day to catch it, when it should be visible for 2 hours.
Actually managed to see it Wednesday night. Was a naked eye slightly fuzzy spot just after sunset.
Tonight wasn’t naked eye, but easy enough in binoculars or a telescope. Sank behind the mountains fairly quickly tho. Should be higher in a darker sky tomorrow.
Hm, as it happens, I’ll be visiting some friends out in the exurbs Sunday, and they usually have pretty good skies. Unfortunately they’re to the East, so what light pollution they have will be in the wrong place, but we’ll give it a try.
Was spectacular tonight. Easily saw the tail naked eye to about three times the width of the moon.
Wow!! That is so awesome!
@Hatchie -
Here you go!
C/2023 A3 Tsuchinshan - ATLAS from the East entrance (south rim) of the Grand Canyon on 10/12:
What equipment and settings did you use to take those pictures?
@Seanette and I plan to go, tonight, to a place oddly-named El Camino de Jerry to try to see, and possibly photograph the comet. At this point, all I have to go on is some guesses as to whether my equipment is even up to photographing it, and how to set it to do so. I’m thinking my ancient (late 1960s or early 1970s) Vivitar 85-205mm ƒ/3.8 zoom lens on my D3200, pointed just above the horizon, where the sun has just set, and rapidly trying different combinations of shutter speed and aperture settings, hopefully at ISO 100 to keep the noise down.
I had three cameras going - my new Z8 (probably need to start a thread on it), my D800E, and my D7200.
The close-up photo was taken with the D800E and my new Samyang 85mm f/1.4. Exposure was 1 sec at f/1.4, ISO 800
Your lens is much slower, so you are going to have two things working against you - star trails and low light. I would crank your ISO to 1600 or more, keep your exposures under 1 sec (or less, if you zoom in), and use the widest aperture you can get away with. I don’t know how good your zoom is wide-open, but you should at least give it a try. Also, focus is difficult and critical, and you will need to re-focus if you zoom. Use the Live View feature to zoom in on a star, and focus on that. The comet is quite faint right now - it was barely a naked-eye object last night.
More info:
- The comet won’t be visible until around 1/2 hour after sunset. Don’t worry if you can’t find it for 30-45 minutes. It’s also a lot higher than it appears in Stellarium - the default viewing angle is wider than the eye’s field of view. You should have at least an hour of good viewing if you have an unobstructed view of the western horizon.
- I was able to get very good shots of NEOWISE with my 80-400mm f/4.5 lens, so not having a super-fast lens isn’t a terrible obstacle. Don’t be afraid to crank up the ISO. You can take a bunch of images and then stack them to reduce noise, but you can’t really de-trail the images if you use too slow a shutter speed.
My Vivitar has some very odd distortions in it, when it is at wide apertures. I actually like those distortions for some artistic applications, but not for this sort of application. It’s much sharper at smaller apertures. I’ll try some shots at ƒ/3.8, but I probably won’t like those terribly well.
ISO 1600 is going to be noisier than I like on my D3200; but maybe not so bad that Topaz Photo AI can’t clean it up to an acceptable level. I’m probably going to have to go with longer exposures than you suggest.
Focus isn’t the issue for me that you think it will be. Old lenses like my 85-205 differ from much more modern lenses, in that there’s a clear ∞ mark, and if you set the lens to that, it really is focused to infinity. Same with a 50mm ƒ/1.4 that I might also try using tonight. Less magnification, but if the comet is big enough, maybe the better quality of this lens compared to the 85-205 might make up for it. Unlike the 85-205, my 50mm is plenty sharp, even wide open, and wide open for it is wider than for the 85-205.
The Z8 is full-framed, right? What Nikon calls FX? So my 50mm on my DX/APS-frame D3200 should actually be roughly comparable to the magnification of your 85mm on your Z8. Perhaps I shouldn’t even bother with the Vivitar at all. Just use my 50mm at ƒ/1.4; if light levels are comparable to yours, 1 second at ISO 800 to 8 seconds at ISO 100; see what range of results I get balancing sensor noise against blurring.
For wider shots, if I think I need them, there’s my equally-ancient 28mm ƒ/3.5, or the “kit lens”; that came with my D3200, which is 18mm to 55mm, with the maximum aperture ranging from ƒ/3.5 to ƒ/5.6 depending on the focal length. I probably won’t use the latter unless I decide I really want a wider shot than I can get with the 28mm. Focusing it for astronomical shots was fairly tricky, until I figured out the trick. Manually focusing it is blind and imprecise, with no focus markings. I eventually figured out that if I push the shutter button on my D3200 with the lens cap on, that the lens stops at infinity, whereupon if I set the camera to manual focus, and leave the lens on auto focus, it stays there. Before I figured that out, I engraved some marks on this lens so that I could manually set it at infinity at either end of the zoom range.
Is there a particular piece of software that you would recommend for this purpose? What image-stacking software I have and have used very much is for focus stacking, to get increased depth of field. I doubt if it is suitable for this form of stacking; but this wouldn’t be the first time I’ve had an application for which I would want to do this kind of stacking.
I use Starry Landscape Stacker (Mac), but there are a lot of options out there.
Yes, the 85mm lens was on a full-frame camera, so 50mm on a DX camera should be good.
I would still check the focus, even with hard stops and your engraved marks - it doesn’t take much to move away from perfect focus.
Well, I did visit those friends, and the good news is, light pollution wasn’t an issue. The bad news is, it was because we had a great view of the H2O Nebula.
Always a problem when it appears!
I decided to see if I could see it from the street in front of my house this evening, and was surprised that I could. The sky glow was ridiculous, but I went and got my new camera and my old 80-400mm lens, and got a semi-decent photo:
Annoyingly bright half-moon certainly doesn’t help.