Abstract Star Trails

Michael Piziak · 10-18-2021, 07:51 PM

Star Trails. This time with the Asahi Pentax M-100mm Macro f4 lens. Still, I'm getting an "uptick" at the end of the trails. Not sure what causes that. I even covered the lens at the beginning of exposure and right before the end of the exposure (without touching the camera using remote with 3 second delay).... I"m told the uptick is actually during the beginning of the exposures that I've been taking. I know I need to get something in the shot besides "just" the star trails to make it interesting... Comments please...

damianc · 10-19-2021, 12:26 AM

Is the surface the tripod is on stable? Something like wooden decking could move as you walk away.
I've taken long exposures in boggy ground and found that my walking away caused the ground under the tripod to shift and blur the exposure.

**ProfessorBuzz** · 10-19-2021, 09:52 AM

Where in the sky were you pointing the camera (or what direction eg somewhat north), and are you in the northern hemisphere?
How long an exposure? guessing maybe 20 minutes?

I suspect the "uptick" is at the start of your exposure - possibly vibration caused by the mirror movement (assuming a DSLR) or post-shutter vibration that lasted a few seconds.

Did you have the mirror locked up?
How solid is the tripod head and tripod - was it thoroughly locked down?
Did you move the camera on the tripod at all just before this? The head may be sagging to a rest position.

Michael Piziak · 10-19-2021, 11:44 AM

Originally posted by damianc

Is the surface the tripod is on stable? Something like wooden decking could move as you walk away.
I've taken long exposures in boggy ground and found that my walking away caused the ground under the tripod to shift and blur the exposure.

I have a 1 gallon jug of water hanging from the tripod for weight. Perhaps my walking caused it, but it shows up in every pic taken about the same.

---------- Post added 10-19-21 at 11:45 AM ----------

Originally posted by ProfessorBuzz

Where in the sky were you pointing the camera (or what direction eg somewhat north), and are you in the northern hemisphere?
How long an exposure? guessing maybe 20 minutes?

I suspect the "uptick" is at the start of your exposure - possibly vibration caused by the mirror movement (assuming a DSLR) or post-shutter vibration that lasted a few seconds.

Did you have the mirror locked up?
How solid is the tripod head and tripod - was it thoroughly locked down?
Did you move the camera on the tripod at all just before this? The head may be sagging to a rest position.

In Eastern U.S. - W.Va., pointing north.

I also suspect it's something like mirror movement. I didn't have the mirror locked up - that would probably solve the problem, will try that next time....

Thanks

damianc · 10-19-2021, 01:01 PM - **1 Like**

Originally posted by Michael Piziak

I have a 1 gallon jug of water hanging from the tripod for weight

That should help with vibration, but if it's swinging in any way that could also be the source of problems.
As a rule I tend to shoot on a 2 second timer and move back from the camera each shot, so would be likely to see any disturbance at the start of the shot.
ProfessorBuzz's suggestion of tripod sag seems a good place to look too.

A quick measurement of the length of the tick relative to length of star trail should give you a good guide to duration of this effect which may help with diagnosis

SpecialK · 10-21-2021, 02:00 PM

Originally posted by Michael Piziak

I know I need to get something in the shot besides "just" the star trails to make it interesting...

Well, this is the critique thread, not trouble-shooting thread, so you said it all for that part.

I don't have the patience for this type of shot...

10-18-2021, 07:51 PM	#1
Michael Piziak Closed Account Join Date: Dec 2013 Location: West Virginia Posts: 2,815	Star Trails Star Trails. This time with the Asahi Pentax M-100mm Macro f4 lens. Still, I'm getting an "uptick" at the end of the trails. Not sure what causes that. I even covered the lens at the beginning of exposure and right before the end of the exposure (without touching the camera using remote with 3 second delay).... I"m told the uptick is actually during the beginning of the exposures that I've been taking. I know I need to get something in the shot besides "just" the star trails to make it interesting... Comments please...

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Star trails question?	barondla	Photographic Technique	9	10-04-2021 12:25 PM
Astro Need advice: Star Trails and Milky Way Wide Field Planned First Attempts	jon.partsch	Photographic Technique	26	06-26-2021 08:28 PM
Landscape First attempt @ star trails	rtmarwitz	Post Your Photos!	12	05-07-2021 04:22 AM
Thematic Post & Discuss Your Astro Tracer Star Trails & Star Shots	wtlwdwgn	Mini-Challenges, Games, and Photo Stories	48	02-22-2021 01:47 PM
"Sail To The Stars" @ Milang South Australia (Star Trails with the DA 14mm f2.8)	Adrian Owerko	Post Your Photos!	15	04-07-2008 06:11 AM

10-19-2021, 12:26 AM	#2
damianc Pentaxian Join Date: Nov 2012 Location: Highlands of Scotland Photos: Gallery \| Albums Posts: 360	Is the surface the tripod is on stable? Something like wooden decking could move as you walk away. I've taken long exposures in boggy ground and found that my walking away caused the ground under the tripod to shift and blur the exposure.

10-19-2021, 09:52 AM	#3
ProfessorBuzz Loyal Site Supporter Join Date: Feb 2018 Posts: 1,903	Where in the sky were you pointing the camera (or what direction eg somewhat north), and are you in the northern hemisphere? How long an exposure? guessing maybe 20 minutes? I suspect the "uptick" is at the start of your exposure - possibly vibration caused by the mirror movement (assuming a DSLR) or post-shutter vibration that lasted a few seconds. Did you have the mirror locked up? How solid is the tripod head and tripod - was it thoroughly locked down? Did you move the camera on the tripod at all just before this? The head may be sagging to a rest position.

10-19-2021, 11:44 AM	#4
Michael Piziak Closed Account Join Date: Dec 2013 Location: West Virginia Posts: 2,815 Original Poster	Originally posted by damianc Is the surface the tripod is on stable? Something like wooden decking could move as you walk away. I've taken long exposures in boggy ground and found that my walking away caused the ground under the tripod to shift and blur the exposure. I have a 1 gallon jug of water hanging from the tripod for weight. Perhaps my walking caused it, but it shows up in every pic taken about the same. ---------- Post added 10-19-21 at 11:45 AM ---------- Originally posted by ProfessorBuzz Where in the sky were you pointing the camera (or what direction eg somewhat north), and are you in the northern hemisphere? How long an exposure? guessing maybe 20 minutes? I suspect the "uptick" is at the start of your exposure - possibly vibration caused by the mirror movement (assuming a DSLR) or post-shutter vibration that lasted a few seconds. Did you have the mirror locked up? How solid is the tripod head and tripod - was it thoroughly locked down? Did you move the camera on the tripod at all just before this? The head may be sagging to a rest position. In Eastern U.S. - W.Va., pointing north. I also suspect it's something like mirror movement. I didn't have the mirror locked up - that would probably solve the problem, will try that next time.... Thanks

10-19-2021, 01:01 PM - 1 Like	#5
damianc Pentaxian Join Date: Nov 2012 Location: Highlands of Scotland Photos: Gallery \| Albums Posts: 360	Originally posted by Michael Piziak I have a 1 gallon jug of water hanging from the tripod for weight That should help with vibration, but if it's swinging in any way that could also be the source of problems. As a rule I tend to shoot on a 2 second timer and move back from the camera each shot, so would be likely to see any disturbance at the start of the shot. ProfessorBuzz's suggestion of tripod sag seems a good place to look too. A quick measurement of the length of the tick relative to length of star trail should give you a good guide to duration of this effect which may help with diagnosis

10-21-2021, 02:00 PM	#6
SpecialK Pentaxian Join Date: Dec 2006 Location: So California Photos: Gallery Posts: 16,481	Originally posted by Michael Piziak I know I need to get something in the shot besides "just" the star trails to make it interesting... Well, this is the critique thread, not trouble-shooting thread, so you said it all for that part. I don't have the patience for this type of shot...