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Fogbows In The Fields - Jan 28th

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Author Topic: Fogbows In The Fields - Jan 28th  (Read 771 times)
martinastro
Martin Mc Kenna
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« on: January 28, 2009, 09:56:22 pm »

Last night a dense fog enveloped my area after midnight and remained here all through the night. Visibility was very bad in the country. However, it brought some nice delights like this fogbow. This is looking N over a field with a bow generated by a sodium street light behind me. The bow was amazing visually, complete, very bright with the base beside me in the field. It was white in colour but had subtle blue and red fringes on the outside and inside. Also on the inside is a dark arc which may be a supernumerary arc. Heligenschein visible around the shadow of my head and the tripod. The bow was over 40 degrees tall so I used a 58mm SWA conversion lens, but even so it did not fit in the frame. Very difficult to capture these. The images were taken between 03.00 and 04.00 UT. Since comet Lulin would be a no-show I thought these would be fun in the mean time.







« Last Edit: January 28, 2009, 10:04:00 pm by martinastro » Report Spam   Logged

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rjgjr
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« Reply #1 on: January 28, 2009, 10:39:59 pm »

Amazing and interesting images Martin!
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jjb
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« Reply #2 on: January 28, 2009, 11:45:06 pm »

Is that up the road martin on the left?
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martinastro
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« Reply #3 on: January 29, 2009, 12:52:34 am »

Thanks very much Richard.

Jonathan....spot on  Smiley, it is indeed. Crewe Road on the left (N) side of the road in the fields.

Cheers
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« Reply #4 on: January 29, 2009, 10:30:16 pm »

Very attractive images, Martin. What were the camera settings?

Today in the evening I also had dense fog (visibility ~100m) but it got more 'clear' until midnight. Hmm, I have just called an overcast weather 'clear'.  Undecided Well, it is already 4 overcast days in a row and possibly several more ahead. But a little piece of hope - possibly clear on next Tuesday.  Smiley
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martinastro
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« Reply #5 on: January 29, 2009, 10:57:14 pm »

Thanks Roman. I used a 58mm wide angle conversion lens attached to my 28mm lens. Shutter speeds were between 25 and 30 sec's with the ISO at 400. Aperture was wide open. Fogbows are big, thick, and close range so they fill the field easily. Really would need a 10-22mm lens or a fish eye to get the whole bow in.

You will get those clear skies...they are long over due!

Cheers
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Paul
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« Reply #6 on: January 29, 2009, 11:23:32 pm »

Martin, that's a fascinating phenomenon, and one that I have never seen!
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« Reply #7 on: January 30, 2009, 12:31:00 am »

Very nice Martin. You seem to have a talent of getting the most out of, what may seem at first glance, a night to be written off entirely!
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Andy
martinastro
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« Reply #8 on: January 30, 2009, 03:25:58 am »

Thanks very much Paul and Andy. It's often on these poor nights that nature provides something else to catch which might otherwise have gone unnoticed. I think that to get a more photogenic bow I would need a night with less fog, but just enough at low levels for a bow. If this happened it would be possible to catch the fogbow with stars above which would be very photogenic. Next time I will try stitching two images together to get the whole phenomena in a single image. B&w seems to be great at picking up the delicate details like the shadow on the inside and supernumerary arcs (lower your head from the screen to see them). I really hope to image a lunar fogbow at some point. I have seen them many years ago but I didn't have a camera then. I have never seen a solar fogbow though.

Here's a question. How can I capture these fogbows at night which show the bows real colour, which is either an off-white or bright pastel shade?. I changed the white balance settings and didn't succeed. I also tried adjusting the levels afterwards but they needed so much change that the image fell apart. Is it possible to get a natural colour or is the sodium light just too strong?. The field was yellow/orange and so was the fog but the bow was not. I would appreciate any advice. Cheers
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« Reply #9 on: January 30, 2009, 08:49:10 am »

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Is it possible to get a natural colour or is the sodium light just too strong?.
You can't colour balance sodium light - it's because it's basically an almost monochromatic emission source. High pressure sodium does have a bit of continuum but is more or less completely lacking in the blue & green (though even low pressure sodium does have a very faint emission line in the blue as well as the two close, bright emission lines in the yellow/orange).

In my experience the best starting point for awkward lighting is to set "daylight" colour balance & shoot in raw. At least you can then tinker with the WB to your heart's content in the raw converter without losing anything.... auto WB can get it very wrong indeed!
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martinastro
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« Reply #10 on: January 30, 2009, 01:36:04 pm »

Thanks for all the info Brian. I have RAW mode on my camera but have never used it before although now I'm tempted to start shooting these and other day time subjects in this format. Would the files eat up much of a 2GB memory card?.

Is there any free RAW conversion software on the net for Fujifilm cameras does anybody now?. I really do need full control of white balance.

Cheers
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martinastro
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« Reply #11 on: January 30, 2009, 02:08:53 pm »

A review I found says that Fujifilm's RAW conversion software is very poor so I will avoid that. I found some links to trial versions of RAW conversion software from other manuafactures. I'm wonderfing if I should just stay with jpeg until I get a DSLR.
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« Reply #12 on: January 30, 2009, 04:27:41 pm »

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Is there any free RAW conversion software on the net for Fujifilm cameras
I don't know about your camera specifically but Adobe Camera Raw is a "free" raw converter plug-in for Photoshop & PS Elements which does the job.
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« Reply #13 on: January 30, 2009, 08:51:11 pm »

Well caught Martin. Might be worth a look at RawTherapee..
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martinastro
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« Reply #14 on: February 01, 2009, 05:05:04 pm »

Thanks guys for the help.
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