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A couple of nights
Lens: 21ltd 10-17-fisheye Camera: K-3, K-5 Photo Location: Whitney, Ontario, Canada 
Posted By: normhead, 09-17-2015, 07:27 PM

A few recent night sky images, one a night is about all we can manage, but I took two cameras, one facing north (DA 10-17 @10mm) and one facing south (DA 21 ltd.) With the 10-17 on the K-3 and 21ltd on the K-5.









Last edited by normhead; 09-18-2015 at 05:31 AM.
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09-17-2015, 08:12 PM   #2
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Dazzling shots, bravo.
09-18-2015, 05:32 AM   #3
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Thanks for commenting
09-18-2015, 06:13 AM   #4
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That's cool -I have not tried star trails - but heading the mountains next weekend may give that a go.

09-18-2015, 06:24 AM   #5
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The problem with the star trails is, you have to stay up really late. These are 1 hour exposures, and took a lot of PP. It's going to take us a while just to figure out how to do this right.
09-18-2015, 06:26 AM   #6
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magical ... marvelous captures! dave m
09-18-2015, 06:34 AM   #7
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Thanks for commenting dave
09-18-2015, 10:19 PM   #8
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These are fabulous, particularly the first and last.

Any general comments on your PP here? I see you used ISO 200, but I can see some noise still. How do you get manage noise on a shot like this? It seems like standard techniques would also smear the stars and trails.

09-19-2015, 07:27 AM   #9
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As far as I can tell, long exposures produce noise.... call it reciproicty failure or something. The anti noise is cracked up, all sharpening is turned off (sharpening tends to emphasize noise) NR is maxed out and I've used a "Skin Smoothin" function that is used to blur out the imperfections in people's skin for portraits. SO full size, everything is quite blurred out. The big issue is that there was not a lot of contrast in the original images and contrast been bumped, much more than usual. All the efforts to reduce the noise are defeated by the +2 to +4 bump in contrast.

Finished file...


The file I started working on.... all the information I needed was there, but the colour channels were all off kilter in relation to each other. Next time out I'll probably experiment with less exposure. I'd like the sky to be black,to my eye, (but obviously not at all black to amore sensitive instrument) because the sky I took the picture of was black except for the glow of Whitney on the horizon.


I actually quite enjoy the variations in colour etc. the camera recorded. To my eye at the time, the sky was just black and the same everywhere,. Through long exposure and amplification it's clear, there was a lot more there than I wa seeing. OF course, most of the time this exposure was happening I was in bed, so really, I don't know what the sky looked like. Maybe someone turned on a light show.

But, on the histogram, the image i underexposed and occupies only the left end of the histogram. Never the less, my next exposure will be a stop less. Interesting, this exposing for black.

Essentially, you would want no exposure on most of the sky with just the stars peeking through..., I guess you have to find the point at which the stars light up, but exposure of the night sky, is suppressed.

But then, I like these, so, I may try and do that, but I'll probably keep doing these too. I'll call them experiments in amplification or something like that.

Last edited by normhead; 09-19-2015 at 07:53 AM.
09-20-2015, 09:13 PM   #10
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QuoteOriginally posted by normhead Quote
As far as I can tell, long exposures produce noise.... call it reciproicty failure or something. The anti noise is cracked up, all sharpening is turned off (sharpening tends to emphasize noise) NR is maxed out and I've used a "Skin Smoothin" function that is used to blur out the imperfections in people's skin for portraits. SO full size, everything is quite blurred out. The big issue is that there was not a lot of contrast in the original images and contrast been bumped, much more than usual. All the efforts to reduce the noise are defeated by the +2 to +4 bump in contrast.

Finished file...


The file I started working on.... all the information I needed was there, but the colour channels were all off kilter in relation to each other. Next time out I'll probably experiment with less exposure. I'd like the sky to be black,to my eye, (but obviously not at all black to amore sensitive instrument) because the sky I took the picture of was black except for the glow of Whitney on the horizon.


I actually quite enjoy the variations in colour etc. the camera recorded. To my eye at the time, the sky was just black and the same everywhere,. Through long exposure and amplification it's clear, there was a lot more there than I wa seeing. OF course, most of the time this exposure was happening I was in bed, so really, I don't know what the sky looked like. Maybe someone turned on a light show.

But, on the histogram, the image i underexposed and occupies only the left end of the histogram. Never the less, my next exposure will be a stop less. Interesting, this exposing for black.

Essentially, you would want no exposure on most of the sky with just the stars peeking through..., I guess you have to find the point at which the stars light up, but exposure of the night sky, is suppressed.

But then, I like these, so, I may try and do that, but I'll probably keep doing these too. I'll call them experiments in amplification or something like that.
Thanks for the explanation. I looked up reciprocity failure and now see the problem. Still, you're right, deeper blacks would probably solve the problem.
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