I obtained an Osmo+ for photographing auroras on a ship during a trip to the Arctic Ocean. Some of the photos are posted here. The auroras look pretty good, but there are star tracks. This seems contradictory -- how can there be star tracks (which indicate motion) if the gimbal remained still enough to produce good images of the auroras? I can think of only one possible explanation: when the exposure starts, there is briefly a little motion before the camera stabilizes, and this is sufficient for the relatively bright stars to produce tracks. If I go on another such trip, I might get someone to hold an obstructing screen in front of the lens and then move it just after I start the exposure.
an odd effect when photographing auroras on a ship
- Thread starter cinclodes
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Nice pictures! We did an Alaska trip six years ago which included the typical tourist stuff and a plane ride around Denali (Mt. McKinley). Wonderful trip and amazing sights to see.
As far as the star tracks, I'll have to let the camera experts address that issue.
As far as the star tracks, I'll have to let the camera experts address that issue.
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Two problems with that explanation: (1) the exposure times were only 10 to 30 seconds; (2) the tracks aren't arcs of circles.
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My opinion is that it is not normal star trails due to long exposure as the lines are not arched the same and are rather squiggly. With trails that long it would have been a rather long exposure, like a couple of minutes. It very well could be some shake of the camera. Maybe using a self timer to open the shutter? Remote shutter release?
I have han pollen being hit by light do similar in long exposures. Could there have been something passing in front of the camera that light relected on?
I would love to see the northern lights as you did. Nice pics.
I have han pollen being hit by light do similar in long exposures. Could there have been something passing in front of the camera that light relected on?
I would love to see the northern lights as you did. Nice pics.
Since the exposure times were only 10 to 30 seconds, the star tracks cannot be due to the rotation of the earth. The whole idea of the Osmo+ is to eliminate the motion of the camera, but it appears from the photos that the camera moves for an instant during the exposure. The only explanation that I can think of is that the shutter either opens just before the camera is stabilized or closes just after the stabilization stops. The best place to see the auroras is far to the north. I had previously seen them mainly from about the latitude of the US-Canada border (but I saw them in Florida in the 1970s). During three sea trips to the Arctic, I had the great fortune of seeing amazing auroras that are intense beams of green light directly overhead -- much more amazing than what I had previously seen further south. There was lots of cloud cover during the trip when I had the Osmo+. Those photos are pretty good, but they don't begin to capture the majesty of the auroras at their best as I saw them on the other trips.
In the original post, I mentioned the idea of using a screen to obstruct the lens at the beginning of the exposure. That test can be done on any night when stars are visible. I will give it a try. I had actually noticed the star tracks before going to the Arctic. I will see if they can be eliminated.
Are you able to post an example so that people have a convenient means of seeing the actual effect (rather than a link to a heap of non related images).
Edit- i have found at some of the images. It’s not star trails. The subject lines appear in substantially similar places in the frame in more than one image and seem to be replicated within the image itself in at least one frame. It might be an out of frame point source of light and/or dust on the front or internal lens elements, filter of the sensor.
Btw- apparent movement of the stars is apparent in significantly shorter exposures than you may realise. It all depends on the focal length and which area of the sky is being images and where you are in earth.
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I posted a link where 16 aurora photos can be found so that anyone who might be interested can see that it wasn't an isolated incident. The star tracks do not occur in the same places, and I know for a fact that they are indeed star tracks because I verified at the time that they correspond to particular stars.
So- you think they are “star tracks” despite your earlier suggestion they can’t be?
Think of the osmo as a tripod- in this case one with long enough legs to reach the ocean bottom.
The images I looked at definately reveal a replicated artificact within a single exposure and across multiple frames.
The tracks are stars, but they are due to camera motion, not the rotation of the earth. The tracks are indeed similar in each photo -- just as one would expect from camera motion. There might be some similarities between the tracks in different photos, but that would be expected if my motion is similar each time I take a photo. Thanks for the inputs.
Ok so it’s good old camera shake- as you suggest it may be attributed to the stabilisation not being active at some point during the exposure or it might be movement/vibration of a type/magnitude that is outside the correction capability of the stabilisation. Either way you should be able to easily clone the lines out- you have some beautiful images there.
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I am not an expert but have been some sort of photography for 45 years. Our high school equipment was better at the time than some of the major Southern California colleges. Our photography teacher use to pound in our heads that you had to take three rolls of film(36 each) to get one good shot. I mean no offense but you did not achieve that. All the photos posted seem to be blurry! Even the ones of birds and such. I think there may be something wrong with the camera or the settings. The only picture that had some sharpness to it was the one that had a signifacant amount of sun in it. I know it was grey and cloudy most of the time from your pictures. Perhaps focus is greatly affected with the low light. The northern lights can be shown to be quite clear. They are not. The tracks are exactry what I would expect seeing the pictures overall. So, I believe that possibly the Osmo/camera or both is working incorrectly. Or you have some kind of settings wrong. This is just my opinion though.
May I suggest that you make an attempt to get razor sharp photos of distant, moving, small objects under low light conditions from the icy deck of a ship that is bouncing along over the waves, with bitter cold wind blowing and spray hitting the camera lens.
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He made an observation and then a valid comment reguarding your question. Rather than getting defensive, maybe you should be appreciative of the effort he gave to help you.
Google 'how to avoid star trails' You will find information on the 500 rule. It is 500 Divided By the Focal Length of Your Lens = The Longest Exposure (in Seconds) Before Stars Start to “Trail”
For example; let’s say you’re taking a shot with a 24mm lens on a full frame camera. 500 / 24 = 21 seconds, which you can round to 20 seconds.
I don't now what the lens is on your Osmo, but I'm guessing you're at something far less than 20 seconds.
For example; let’s say you’re taking a shot with a 24mm lens on a full frame camera. 500 / 24 = 21 seconds, which you can round to 20 seconds.
I don't now what the lens is on your Osmo, but I'm guessing you're at something far less than 20 seconds.
You also have add in the crop factor for the sensor size of the camera. The example above uses a full frame camera. Those cameras have a crop factor of 1 to 1. Your Osmo uses a 1/2.3 sensor that has a crop factor of 1/5.62. So if your Osmo has a 20mm lens you are going to be around a 5 second shutter length before seeing star trails. 20mm X 5.62=112.4 , 500 divided by 112.4=4.45 seconds.
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Man I don't see anything wrong with any of your pictures,I was mesmerized couldn't stop watching videos then watched the pictures they were so nice I could hear the wind and feel the cold you have one of the best jobs on earth!!Great Job!!
