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maddycanon
30-06-2014, 9:04pm
Hi there :)
I've shot a few star trails over the past few months, and a few times I've run into this problem of 'wobbly' star trails. I've tried weighing down the tripod, but even on really still nights with no wind it ends up really scattered. All the photos were triggered by a remote (so I didn't touch the camera between photos).

I have a relatively cheap tripod, but I don't have the funds (broke uni student) to get a proper heavy tripod. Am I doing something wrong? Anything I can do better in terms of reducing and preventing the scattered stars?

example 1:
canon 600D, tamron 18-270mm lens.
19 photos @ ISO 400, f/3.5 and 30 seconds exposure.
I was set up on my veranda, there was no wind at all.
109974109975

Example 2:
canon 450D, 18-55 kit lens + fish eye extension
100 photos @ ISO 1600, f/3.5 and 30 seconds exposure.
set up in a field, slight breeze. I had my car parked behind the tripod to block the breeze a bit (and for me to sit and wait in :th3: )

109976109977


Cont. in comments >>

maddycanon
30-06-2014, 9:07pm
cont. from above ^^

And here are some of my better ones, but still taken under the same circumstances.

Example 4:
canon 450D, canon 18-55mm kit lens + fish eye extension
3 photos @ ISO 100, f/8 and 30 minutes exposure.
camera sitting on tripod in the middle of a car park, not much breeze.
109979109980


example 5: (first star trails try!)
canon 450D, canon 18-55mm kit lens + fish eye extension
42 photos @ ISO 400, f/3.5 and 30 seconds exposure.
I pressed the shutter manually, still managed no camera shake?
109981


and just for fun, one more:
same night and gear as above.
5 photos @ ISO 400, f/3.5 and 4 minutes exposure
I was in bulb mode and I held the shutter down manually (before I invested in a remote) and still managed to keep still enough for this to come out ok. :rolleyes:
109982

ameerat42
30-06-2014, 9:09pm
If you have tried to effectively immobilise the camera as you described, then I can only suggest that you may have had IS, or
image stabilisation, switched ON. The camera thinks it has to make adjustments when it doesn't, and instead, gets the wobbles.
Are you able to check whether this was the case?

Am.

I didn't see your edit of the above post before my reply. Still, no other suggestion.

wasnapper
30-06-2014, 9:23pm
How about shake from the mirror? Can it be locked up?

maddycanon
30-06-2014, 9:57pm
So I should have image stabilisation switched off? That could be my problem, thank you! I may have accidentally turned it off while switching between auto and manual focus on the lens (and hence the clearer trails).

- - - Updated - - -


If you have tried to effectively immobilise the camera as you described, then I can only suggest that you may have had IS, or
image stabilisation, switched ON. The camera thinks it has to make adjustments when it doesn't, and instead, gets the wobbles.
Are you able to check whether this was the case?

Am.

I didn't see your edit of the above post before my reply. Still, no other suggestion.

So I should have image stabilisation switched off? That could be my problem, thank you :)

MarkChap
30-06-2014, 10:03pm
It really seems the worst of the images is with the 18-270, that is a big chunk of glass, relatively, to be hanging off a cheap tripod.
It is not just the legs, but all the connections that can move, I would hazard a guess that is where a lot of the issues lie.
A combination of, cheap tripod, heavy glass, mirror slap

nardes
01-07-2014, 6:58am
Another candidate for these irregular wobbles is “traffic” noise. If your veranda is a wooden balcony, then people walking around will cause the wooden boards to deform and the result will be small deviations in the star trails.

Wind gusts can also lead to wobbly star trails as the tripod flexes.

Yes, turn OFF the IS function when shooting long exposures from a tripod mounted camera.

Cheers

Dennis

Mark L
01-07-2014, 10:25pm
Yep, make sure image stabilisation is turned off for long exposures. Shake from the mirror is probably not the problem withe the long eposurel (it may be).
Always better to set to live view (locks mirror up) and use 10 sec. self timer to stop any shake from the camera on tripod.

hakka
02-07-2014, 10:06pm
Always better to set to live view (locks mirror up) and use 10 sec. self timer to stop any shake from the camera on tripod.

That won't work for a startrail.

Astroman
03-07-2014, 6:18am
Hope you got it all sorted, yes looks very much like IS. Looks like some great locations you have there for some interesting trails. I would recommend sticking with the smaller lenses, and wider FOV. Keep you tripod low with the legs in, to reduce any vibrations from wind etc. What programs did you use for the stacking?