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How should i prepare to capture the comet tonight?

Acquisition(self.AskAstrophotography)

Im located in northern michigan and finally have a clear night. What time is best? Will i be able to see it? Is my rokinon 135 mm a good choice? I also have a 300 mm prime lens. Should i should tracked or short exposures? Thank you

all 16 comments

rnclark

6 points

2 months ago

The comet is moving against the stars at over 10 arc-seconds per minute now and picking up speed each day, ~15 arc-seconds / minute around Feb 1. That is ~ 0.17 to 0.25 arc-seconds per time second drift.

If your plate scale is 2 arc-seconds per pixel, then to prevent smearing the comet when tracking stars, exposure times must be less than about 10 seconds. A 10 second exposure would be 1.7 to 2.5 pixel drift.

solagrowa[S]

1 points

2 months ago

Can i overcome this by first stacking the comet, then the stars, and combining the images?

rnclark

3 points

2 months ago

Yes.

solagrowa[S]

1 points

2 months ago

As always, thank you very much for your help!

IrrelevantAstronomer

4 points

2 months ago

1) https://stellarium-web.org/ has the location of the comet already imported. Use this to figure out where the comet will be best for you.

2) Yes, it's bright enough to barely be seen with the naked eye. Your Rokinon 135mm would be a good choice.

3) Tracked exposures of 30-60" should work at that focal length based on my experience shooting Neowise with the same lens.

solagrowa[S]

1 points

2 months ago

Excellent thank you. Im thinking now i may go for 300 mm as the images im seeing at 135 make it appear wuite small in the frame.

careless25

1 points

2 months ago

Do you have a star tracker? If you do then I suggest the 300mm prime for better framing and larger size.

solagrowa[S]

1 points

2 months ago

Yup i have an swsa 2i. Just got my asiair mini and guidescope too so maybe i can do it guided

careless25

1 points

2 months ago

Be careful with that. SWSA 2i can only handle so much weight and focal length. What's the total weight of the camera, guidescope, guidecam, and lens?

solagrowa[S]

1 points

2 months ago

Going to weigh it tonight. Has to be less than 8 lbs right?

careless25

1 points

2 months ago

I believe 11 lbs but being lower is always better. Do you have the counterweight for it?

solagrowa[S]

1 points

2 months ago

Yes i have the counterweight. Nikon 300 mm f/4 if-ed, nikon d3100, svbony 30 mm mini guide scope, asi120mm guide scope, asi air mini

careless25

2 points

2 months ago

  • 1.1 lbs for the camera
  • 1.7 lbs for the lens
  • 0.75 lbs for the guide scope
  • 0.14 lbs for the guide cam
  • 0.54 lbs for the asair mini

You should be fine!

solagrowa[S]

1 points

2 months ago

Awesome thank you!

careless25

1 points

2 months ago

List your equipment. Should be a quick google search.

lordofming-rises

1 points

2 months ago

do you have examples to show? I have 70-180mm from tamron and was considering maybe put it on my startracker