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2009 Noctilucent Cloud Season

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Author Topic: 2009 Noctilucent Cloud Season  (Read 15730 times)
martinastro
Martin Mc Kenna
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« Reply #165 on: June 19, 2009, 03:05:54 pm »

Thanks very much John, I hope you get a good clear night soon, you deserve it.

Here's a few from last night...











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brianb
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« Reply #166 on: June 19, 2009, 03:38:17 pm »

Quote
Here's a few from last night...
Wow, I could see something was going on but I'd no idea I was missing that wonderful display.....
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rjgjr
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« Reply #167 on: June 19, 2009, 03:45:45 pm »

Those are just incredible Martin, almost reminds me of some sort of lightning diplay. Just beautiful!!. Since I have never seen any NLC displays, let me ask a couple of questions to all of you. I'm sure the legnth of camera exposure enhances the brightness somewhat, but how much, are they nearly as bright as presented? Do they last all night? Being at the higher latitudes, does it get completely dark at night?. Just curious. Thanks to all for msuch great images.
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Paul
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« Reply #168 on: June 19, 2009, 04:00:26 pm »

Hi Richard,

I'm sure Martin and John will be along with more details soon, but here's my take on your questions....

The camera exposure does enhance the effect - the exposures tend to be a few seconds at moderate sensitivity - in fact a lot of mine are shot at ISO 100 - my Dimage A2 bridge camera is noisy at anything higher - but the NLCs are very visible to the naked eye. Estimating magnitudes is difficult with such big objects, but the brightest stars in the area such as Capella, Mirphak and Algol will generally shine through NLCs whereas dimmer stars will generally not be so visible, so you could say that perhaps the clouds are equivalent to 2nd mag stars on average.

NLCs can last all night, indeed it is usually the oncoming dawn that brings displays to the end.

No, it doesn't get completely dark at night. Here, just under 55deg N there is still plenty of light in the sky at 0124 BST which is the time that the Sun is furthest below the horizon. From mid-May to the end of July one can pretty much forget about looking for faint galaxies and the like - the sky is simply too bright. Some, like us here, go for the NLCs, some observe double stars and planets.

Hope that helps!
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martinastro
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« Reply #169 on: June 19, 2009, 04:21:58 pm »

Thanks very much Brian and Richard.

Richard, camera's can enhance the brightness, but only if you overexpose the image. Those images from last night match what I seen from here, I always try my best to record the image as seen visually, this what I have been doing with all NLC images this season. The difficult part is the motion, NLCs will drift slightly even during a short exposure often blurring/trailing on the image. High ISO and short shutters reduce this effect, since my camera is noisy I use a low ISO and a slightly longer shutter. Those were taken using ISO200 last night which shows how bright the NLCs were, any higher and the image would have been burn't out. With the naked eye they cast shadows, illuminated the fields in the country, and reflected their multi colours off patches of ordinary cloud in the sky which was amazing. As John 9929 has done in the past - you can read a newspaper at night due to their brilliance. A type 5 display will get the attention of anyone who even glances out the window at the sky.

As for the stars, the brightest stars may be faintly seen through a bright type 4 display, however a type 5 show, like last night's, and the night before, will wash even the brightest stars from the sky. I would estimate that the recent displays were similar to the mag of planet Venus, if not much brighter, the same thing was seen during the 2008 season also when Venus was blocked out by NLC. So, in a nut shell, they are extremely bright!. Images don't enhance the mag in my opinion onless they are overexposed. They have got to be the most difficult subject to shoot. Bright twilight is with us for much of the short nights here, however during the middle of the night the twilight darkens further which is the best time to see NLCs, in my opinion,because  the colours and brightness jump out from the sky, and the more oblique viewing angle presents wonderful structures.

As for the display last night, the camera picked up the white and blue colours but missed out on the lovely yellow, green, and gold tones.
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Tyler
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« Reply #170 on: June 19, 2009, 05:15:35 pm »

Are you kidding me?Huh  Martin has the bightest recorded NLC's I have ever seen a picture of!! Congrats Martin and fantastic work to capture them! Spaceweather homepage is nothing new to you lol. I think you could get a lot of international attention for those, like news stations that want to use the images and whatnot. Your persistance has paid off! Well done and congratulations Martin !
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« Reply #171 on: June 19, 2009, 06:09:55 pm »

Richard, I would go along with everything the guys have said, but would add that in my experience NLC's are very difficult to image. You have to have that "feel" for them and practice is the only way I'm afraid. With the comming of digital cameras it has become a bit easier because you can actually see what the result is in seconds. Unlike the film cameras where you had to wait maybe a fortnight to see the results. Digital IMO don't pick up some of the beautiful colors that was present in last night's display, so there's still room for film if you can wait on the results. I was frustrated by cloud last night but still got a few images and will post a couple later. I actually waited up late to try for the Mare Orientale on the moon and set up my equipment. I thought the NLC display was over but when I put on the webcam I found I couldn't get a focus nomatter what I tried. It was then that I discovered that faint NLC's were passing over the moon so end of imaging! This is a strange season for NLC's, as every display so far has been different with different structures. I don't know why that is, even the experts don't know for sure. BTW, Martin is correct about reading the newspaper by their light. I was on holiday in the north of Scotland in the 1970's? when we had a wonderful display, and we tried that experiment. The display on the 16th here I could read the camera settings with no problem, so they can be very bright particularly in high latitudes, so much so that it's very hard to get a correct exposure without overexposing, it's back to parctice again I'm afraid!

Martin, you got some very interesting images there showing lots of strange structures, well done on getting SW homepage. I have'nt sent any in to SW for a few days as he tended to ignore my images from the 16th, the ones with the "blue fog".
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martinastro
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« Reply #172 on: June 19, 2009, 07:00:00 pm »

Thanks very much Tyler, very much appreciated!, I think a big congrats is in order to you Tyler on catching two tornadoes and amazing storm structures with stunning images to match!. I knew you would catch one this year.
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mark c
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« Reply #173 on: June 19, 2009, 07:56:33 pm »

Hello being visting this site for a while now, i would just like to show the results of my first time to photograph Noctilucent clouds 0n the night of 17 June these were taken between 11:30pm and 12:30am with a Nikon D80 Various settings. Any advice much appreciated.

Mark
http://i43.tinypic.com/fwsu1z.jpg[/img]]
http://i43.tinypic.com/rkwsh5.jpg[/img]]
« Last Edit: June 22, 2009, 03:42:44 pm by mark c » Report Spam   Logged
martinastro
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« Reply #174 on: June 19, 2009, 08:14:38 pm »

Hi Mark, many thanks for sharing your NLC images, only thing is, I can only see a white box with a red X. The images must not have uploaded properly. It would be great if you would re try, tinypic works very well.
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Paul
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« Reply #175 on: June 19, 2009, 08:19:52 pm »

Hi Mark,

Welcome to the Forum! The Good News is you're in the right place - we have a combination of skills and raw enthusiasm here that is unrivalled on this island and we're all still learning!

The Bad News is - I can't see your images! We have no space of our own here so photos need hosted off-site - eg Flickr, Photobucket etc - I use my own webspace. You then insert the image URL between tags in your message and voila!

Look forward to seeing your shots!

Clear skies,

Paul.
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rjgjr
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« Reply #176 on: June 19, 2009, 09:18:05 pm »

Again, I'd like to thank everyone for posting these magnificent images, and for the wealth of information about NLC's. From anything I have seen on the internet, all of your images are the best. I was in Circle, Alaska one June about 10 years ago backpacking, and in a very remote, dark site, so I thought. I couldn't wait for the first night to check out the dark skies. Trouble was, the sun was only below the horizon for about 2 hours! Thanks again!!
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John9929
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« Reply #177 on: June 19, 2009, 10:32:29 pm »

A couple from this morning! The orange glow is from Belfast International Airport!




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martinastro
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« Reply #178 on: June 19, 2009, 10:42:47 pm »

Very nice images John, the first one looks fantastic with the red glow on the clouds, there's lots going on there!

Thanks again Richard, those are very kind words.
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Tyler
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« Reply #179 on: June 20, 2009, 12:24:44 am »

Great images John, I can't get over how bright those are!
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