Star trails - how to do it properly?

09/21/2010 03:23:12 PM · #27

:-P

Tamron 16-300mm Di II VC PZD MACRO w/Canon Nikon mount

09/21/2010 03:27:17 PM · #28

so pretty much what everyone is saying, is that you need short exposures and a LOT of them and then stack them

09/21/2010 03:30:03 PM · #29

Originally posted by JulietNN:

so pretty much what everyone is saying, is that you need short exposures and a LOT of them and then stack them

If you want to sit at the cool kids' table during lunch period, yes.

Tamron 16-300mm Di II VC PZD MACRO w/Canon Nikon mount

09/21/2010 03:34:05 PM · #30

I was so not a cool kid at school.

DrAchoo

Panasonic Lumix DMC-LX5

Canon EF 24-105mm f/4.0L IS

09/21/2010 03:40:41 PM · #31

Originally posted by JulietNN:

so pretty much what everyone is saying, is that you need short exposures and a LOT of them and then stack them

Well, apparently not if that's illegal and william's shot stands. His shot doesn't appear to have a ton of noise in it.

09/21/2010 03:42:04 PM · #32

Originally posted by JulietNN:

I was so not a cool kid at school.

Nobody at DPC was. I meant in relative DPC-terms. The way Art Roflmao spends lunch period in a smoked-filled car.

Tamron 16-300mm Di II VC PZD MACRO w/Canon Nikon mount

09/21/2010 03:43:47 PM · #33

I was cool after I got expelled from the private girls school.

Noooooooooooot so much with my parents though =\

09/21/2010 03:43:54 PM · #34

Originally posted by DrAchoo:

Originally posted by JulietNN:
so pretty much what everyone is saying, is that you need short exposures and a LOT of them and then stack them

Well, apparently not if that's illegal and william's shot stands. His shot doesn't appear to have a ton of noise in it.

I made an hour long star trail shot with my Rebel that wasn't noisy, but I let the camera run it's anti-noise routine at the end of the exposure, which took another hour. It wasn't such a nice shot, though.

09/21/2010 03:45:04 PM · #35

Originally posted by JulietNN:

I was cool after I got expelled from the private girls school.

Noooooooooooot so much with my parents though =\

Oh my! LOL! What did you do to deserve that, may I ask?

Tamron 16-300mm Di II VC PZD MACRO w/Canon Nikon mount

09/21/2010 04:03:02 PM · #36

It wasn't illegal and there wasn't a car. ='O

jomari

Nikon D7000

Nikon AF-S DX 18-105 f/3.5-5.6 ED VR

09/21/2010 05:16:58 PM · #37

Can someone explain to a complete dunce why star trails appear as they do? What is the central rotational point? Why doesn't the rotation of the Earth make them rise in the east and travel over to the west as the sun and moon do?

Nikon AF-S DX 18-105 f/3.5-5.6 ED VR

09/21/2010 05:52:37 PM · #38

Originally posted by jomari:

The "single rotational point" is where the axis of the earth is pointing at. Basically, where the north star is, in the Northern Hemisphere. So everything makes circles around that as the earth rotates.

R.

jomari

Nikon D7000

09/21/2010 06:00:45 PM · #39

Originally posted by Bear_Music:

Originally posted by jomari:
Can someone explain to a complete dunce why star trails appear as they do? What is the central rotational point? Why doesn't the rotation of the Earth make them rise in the east and travel over to the west as the sun and moon do?

The "single rotational point" is where the axis of the earth is pointing at. Basically, where the north star is, in the Northern Hemisphere. So everything makes circles around that as the earth rotates.

R.

Thanks for the explanation, Robert. It raises a some more questions. Do the circular trails appear because the stars are so much further away than the sun/moon/planets? Does latitude have any affect on the apparent position of the trails?

yanko

Canon EOS-5D Mark II

Carl Zeiss 50mm ZE f/1.4 Planar T for Canon

09/21/2010 06:04:53 PM · #40

Originally posted by DrAchoo:

Couldn't he have used noise reduction in post? It looks like he applied a lot of it. The landscape has almost no fine detail and looks like those primitive shapes you find in a 3d modeling program.

Message edited by author 2010-09-21 22:05:10.

Tamron 16-300mm Di II VC PZD MACRO w/Canon Nikon mount

09/21/2010 06:11:45 PM · #41

I tried noise reduction on my shots, but found I lost so many trails when i did it.

I drank 8 cups of coffee so I could go out and shoot some stars (and Jupiter) tonight to try out all these shots.

Looked out the window and it is completely cloudy and now I have to sit in the corner with caffeine jitters for most of the night. Not cool!

Carl Zeiss 50mm ZE f/1.4 Planar T for Canon

09/21/2010 06:25:21 PM · #42

Originally posted by jomari:

No, the planets make circular trails too if you point the camera at the pole star. You'll get circular trails wherever you go, also, if you point the camera at the pole star: it's just a question of at what declination ("altitude") the point of rotation appears. If you are at the Pole, the point of rotation is directly overhead. The closer to the equator you get, the closer to the horizon the point of rotation is.

R.

Message edited by author 2010-09-21 22:26:14.

kirbic

Canon EOS R5

Canon RF 24-70 f2.8 L IS

09/21/2010 06:25:56 PM · #43

Originally posted by jomari:

Do the circular trails appear because the stars are so much further away than the sun/moon/planets?

Nope.

Originally posted by jomari:

Does latitude have any affect on the apparent position of the trails?

Oh, yes. At the North Pole, the center of rotation will be directly above you, because you are standing on the axis of rotation. At the Equator, the centers of rotation will be at the horizon, both directly north and south of you, because you are standing 90 degrees from both the North and South Poles.

ETA: Robert beat me to it, LOL!

Message edited by author 2010-09-21 22:26:56.

yanko

Canon EOS-5D Mark II

09/21/2010 06:44:46 PM · #44

Originally posted by JulietNN:

Have you tried masking out th trails and then applying the noise reduction to just the shadow area?

DrAchoo

Panasonic Lumix DMC-LX5

Canon EF 24-105mm f/4.0L IS

09/21/2010 06:48:31 PM · #45

Originally posted by yanko:

Originally posted by DrAchoo:

Originally posted by JulietNN:
so pretty much what everyone is saying, is that you need short exposures and a LOT of them and then stack them

Well, apparently not if that's illegal and william's shot stands. His shot doesn't appear to have a ton of noise in it.

Couldn't he have used noise reduction in post? It looks like he applied a lot of it. The landscape has almost no fine detail and looks like those primitive shapes you find in a 3d modeling program.

Oh yeah, I totally agree he did. Plus he can take advantage of the canvas size being only 800 pixels (which reduces noise even more). BUT, he did do a good job preserving the trails which can be hard with the noise reduction.

louinsd

Sony DSLR-A900

Sony 16mm f2.8 (E-mount)

09/21/2010 07:01:42 PM · #46

I've been playing with star trails lately... this is what I've learned....

1. It's dark outside... carry a good flashlight. Yeah I'm smart, but not always that bright.
2. If you are doing star trails in the desert, don't wear sandles. Cacti will stick to your toes.
3. Respect the moon. A little moon will light up your foreground. Too much will make it seem like mid day.
4. It is better to over expose a little and dim the brightness in photoshop than to underexpose. Increasing brightness in ps tends to make the picture more grainy and adds gradients.
5. Star trails are cool... but it's still all about the foreground. Co-centric lines are boring.
6. Learn to light up your foreground. (I'm still learning this).
7. Critters come out at night. Doing star trails on mountain paths will be scarey as the critters make noises and you don't know how dangerous they are.
8. Bring something to do... I have a word game on my cell phone.

I did a really cool one last weekend that I will be submitting for the September challenge.

Message edited by author 2010-09-21 23:49:18.

GeneralE

Canon PowerShot S3 IS

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

09/21/2010 07:40:29 PM · #47

Originally posted by louinsd:

I've been playing with star trails lately... this is what I've learned....

1. It's dark outside... carry a good flashlight. Yeah I'm smart, but not always that bright.

If you were that "bright" you wouldn't need the flashlight!

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

09/21/2010 07:46:30 PM · #48

Originally posted by GeneralE:

Originally posted by louinsd:
I've been playing with star trails lately... this is what I've learned....

1. It's dark outside... carry a good flashlight. Yeah I'm smart, but not always that bright.

If you were that "bright" you wouldn't need the flashlight!

I'm pretty sure that's what he meant :-) That's how I took it, anyway...

R.

GeneralE

Canon PowerShot S3 IS

09/21/2010 07:48:25 PM · #49

I took it that, this time, the flashlight was forgotten, since one learns from one's mistakes.