Zion Star Trails

dave6253

This was my very first attempt at stacked star trails. I took the shots in November, but just got around to learning what to do with them.

It was a very dark and moonless night. The wind was also very high and gusty. I couldn't use a tree in the foreground due to the winds.
This was shot from one of the pullouts along the highway near the long tunnel entrance.

I shot 400, but used only 365 exposures at 25 seconds, 5 seconds between, and 1 exposure at about 10 minutes for the foreground. I left a 2 minute gap between the first and second shot.
I used the Lens Blur Filter on the first and slowly tapered the opacity in the remaining shots all the way from 100 to 1 %.

Stumblebum

What's up with the dots in front of more prominent trails? I think the gap or missing frames might be causing it. They are also creating a criss-cross pattern on the left hand side of the trails.
Perhaps it was intentional.

kdog

Awesome! Merging in a longer exposure for the foreground was a great idea.

dave6253

Stumblebum, The gap was intentional, as well as the larger stars on the first frame. I followed the steps in the PS method of the tutorial here: http://www.shainblumphoto.com/Tutorials
The effect is probably better for shorter trails and with all of the stars falling, in other words, not pointed at the center of the circle. The criss-cross pattern only appears for me if viewing smaller sizes (like on my phone). You get a moire' type effect due to so many parallel lines so close together. Try viewing on a full-size monitor if you haven't.

Thanks for the comments, guys!

Stumblebum

dave6253 wrote: »

Stumblebum, The gap was intentional, as well as the larger stars on the first frame. I followed the steps in the PS method of the tutorial here: http://www.shainblumphoto.com/Tutorials
The effect is probably better for shorter trails and with all of the stars falling, in other words, not pointed at the center of the circle. The criss-cross pattern only appears for me if viewing smaller sizes (like on my phone). You get a moire' type effect due to so many parallel lines so close together. Try viewing on a full-size monitor if you haven't.

Thanks for the comments, guys!

Thanks for the info! I thought it was intentional....but not sure! Cheers!

JC

dave6253 wrote: »

Stumblebum, The gap was intentional, as well as the larger stars on the first frame. I followed the steps in the PS method of the tutorial here: http://www.shainblumphoto.com/Tutorials
The effect is probably better for shorter trails and with all of the stars falling, in other words, not pointed at the center of the circle. The criss-cross pattern only appears for me if viewing smaller sizes (like on my phone). You get a moire' type effect due to so many parallel lines so close together. Try viewing on a full-size monitor if you haven't.

Thanks for the comments, guys!

Good application of the technique, I would do a few things differently, you may or may not agree with me, but I'll throw out some of my personal preferences.

I concur that leaving the gap between the accent shot and the trails doesn't work that well with N star circles, because the gap changes with the angular distance from the North star, I think it would work better to leave no gap and have the first shot defocused, or blurred in post as you did.

I think the foreground would do better either more illuminated, or in profile, as it is, to me, it just seems a little muddy. It's hard without a moon, but if you set up at sunset, you could have added back in some of the sunset illumination.

Sometimes I like shifting the color balance towards blue for startrails or widefield astrophotography, for example, if I have to deal with a lot of city sky glow reducing the red channel cuts out some of that, and sometimes shifting the color balance cooler just fits with the perception of the scene . Zion though, is all about warm colors, oranges and pinks and yellows and reds-I think this would have been a totally awesome shot if you'd left the star colors in to mirror or play off the colors of the rocks.

But for your first attempt, this is really well done, beats my first few attempts.

Why did you leave 5 seconds between shots though? At the scale the image is posted, it doesn't look like 5 seconds, actually, but if that wasn't a typo, you must see gaps at full size.

dave6253

JC, Thanks for taking the time to post thoughtful comments. I actually agree with everything you said. I never really liked the foreground. That was one reason I let the files sit on my hard drive for 6 months. The foreground was lighter, but looked out of place and had an unusual color cast that I couldn't get right, so I brought the exposure down some.

Why the 5 second gaps between each? The built-in intervolometer on the Pentax K-5 I used wouldn't shoot 30 seconds every 30 seconds. I had to back the time off to 25 seconds and leave the gap, otherwise it would only shoot one image and stop. The small gaps are very noticable at full-size.

JC

dave6253 wrote: »

Why the 5 second gaps between each? The built-in intervolometer on the Pentax K-5 I used wouldn't shoot 30 seconds every 30 seconds. I had to back the time off to 25 seconds and leave the gap, otherwise it would only shoot one image and stop. The small gaps are very noticable at full-size.

I don't know Pentax, but that sounds like a shot mode problem. Did you change the image mode from single shot to continuous or multiple shot mode? For Canon and Olympus in bulb mode, with an external intervalometer, the minimum spacing setting is one second, and it doesn't matter what the image mode on the camera is. But, if I don't need the timer delay*, I usually just set the shutter speed on my camera to 20 or 30 seconds and lock the intervalometer shutter button open (or use a simple corded shutter button). For that setting, the camera needs to be switched from single shot to multiple or continuous mode. Maybe it's the same for Pentax.

* and know that my batteries will run out before the sensor has to face the sun.

Glenn5995

Impressive!