Moonshine puzzle

[davefrance]

A couple of nights ago I was trying to take a series of pictures of Orion (for stacking) but the moon was directly above making it a little difficult. In an attempt to block out some of its glare I positioned myself under our covered terrace. When I came to look at the photographs I noticed three or four streaks of light that appeared to be orbiting the moon. First I thought must be reflection through camera lens or dirt  but then I noticed that they were moving in subsequent shots. Each shot was 20 seconds so stars are still circular. Have taken further shots without cleaning lens and no streaks. The streaks are very clear on original RAW image, I have cropped the attachment to try and retain visibility of the streaks. Hope they can be seen.

Anyone any ideas?

[JamesF]

I wonder if they might be bits of spider's web or something similar caught in the twigs visible in the photograph, perhaps with some dew covering them?  Obviously you'd only get reflections from the bits that were suitably aligned and as the Moon moved they might appear to move as well?  They look about the same amount "out of focus" as the twigs to me, suggesting they're at about the same distance?

James

[davefrance]

^{Good suggestion, hadn't thought of that. Will check in the morning see if there are any webs still there.}

[Fypunky]

I wonder if they might be bits of spider's web or something similar caught in the twigs visible in the photograph, perhaps with some dew covering them?  Obviously you'd only get reflections from the bits that were suitably aligned and as the Moon moved they might appear to move as well?  They look about the same amount "out of focus" as the twigs to me, suggesting they're at about the same distance?

James

That's was my thought as the blur of the streak pretty much matches the blur of twigs so in my mind they are in the same depth of field.

[davefrance]

Thanks both for your suggestion, I agree it is the most likely answer......but I have inspected the whole length of the vine (24ft) and its surroundings last night (by torch) and again in the light today and to my amazement I cannot find a single web. That's not to say there wasn't one the night of the photo. By comparing the actual area with the photograph I have ruled out light reflecting of any of the vine tendrils or any other obstruction. The width of the vine covered by the streaks is around 35cm - 14", that would be quite a large web or more than one close together. Guess it will remain a puzzle.

Thanks again.

[Fypunky]

It is a little weird, if you go the brighter star 6 Oclock from the moon and then move to the three fainter stars going to 1 O clock, there appears to be a very faint line there too, out of interest how long was the exposure? If there are no webs so to speak I am wondering if it is maybe insects that are flying at the time and the light is reflecting of them!

[Fypunky]

sorry didnt see the 20 second exposure bit

[davefrance]

I think 20 second exposure rules out flies etc unless they just catch the light for an instant. There also seems to be a definite arc. It's also very cold here now so not much in the way of flying insects.

I wish I could post the original RAW images (20mb) as they are so much clearer. The bright yellow/orange star is Betelgeuse,

On the originals, I cannot see any streak by the three white stars at 1 O'clock. I think there is another one or two streaks further in amongst the vine branches. If I magnify the streak at 7o'clock to moon then half is red and half is blue.

For interest .......here is my finished attempt at the Orion Constellation (no streaks in sight)

[AlexB67]

I wonder if they might be bits of spider's web or something similar caught in the twigs visible in the photograph, perhaps with some dew covering them?  Obviously you'd only get reflections from the bits that were suitably aligned and as the Moon moved they might appear to move as well?  They look about the same amount "out of focus" as the twigs to me, suggesting they're at about the same distance?

James

I'd go with that

[Joves]

One of your stars looked very odd indeed... I got all excited and then realised it was a bit of crud on my ipad screen