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Morkel Erasmus
05-25-2012, 03:59 PM
We spent last weekend in the bushveld, and with it being "new moon" I was able to do some night photography.
I normally like to include some foreground element in these "milky way" shots, but with it being so vivid overhead and arcing from one end of the sky to another right over my head, I pointed the camera skywards.
There was some light pollution from nearby settlements that warmed up the scene too much, so I switched to Tungsten WB for a more vivid colour contrast.

Techs:
Nikon D3s with Nikkor 14-24mm f2.8 @ 14mm
f4.0 @ 20 seconds @ ISO-12800
Decided to push the D3s settings a bit here :t3

Derek Willcox
05-25-2012, 04:50 PM
morkel i like this a lot reminds me of some thing out of a scfi movie your nikon really gets a work out with the iso

Roger Clark
05-25-2012, 05:18 PM
Hi Morkel,

Very impressive for 20 seconds at f/4. Really nice. It sure shows the center bulge of the galaxy. Nice to see the scene stretching all the way to the Coalsack on the right (I so rarely get to see it these days--maybe my next trip to the Serengeti). I would tray and make a gradient to the lower left corner and use it to subtract out the red skyglow from the light pollution. Maybe a simple feathered selection of the corner, then use the levels tool on the red channel and bring the left slider up -- that is a subtraction. The challenge will be getting the feathering right.

Roger

Andrew Aveley
05-26-2012, 09:34 AM
hey Morks , nice colours and tones.looks a little to 'ruff" and some noise is evident.may just be the compression on resize . Also try some LCE here, it will help with 'pop factor" IMHO

Rachel Hollander
05-26-2012, 10:19 AM
Morkel - really impressive especially with the settings. I like how you've framed it and have the bulk of the milky way running corner to corner.

TFS,
Rachel

Don Lacy
05-26-2012, 12:42 PM
Amazing sky Morkel.

Morkel Erasmus
05-27-2012, 02:02 AM
Thanks folks.

Andrew - yeah compression not kind to ISOs as high as this. Obviously there is some noise in the image (anyone thinking that a long-ish exposure at ISO-12800 wouldn't have noise is a bit naive)...the thing is that there's still a lot of dynamic range and tonal quality here. I did add some LCE to add some pop...always feel that running too much LCE makes it appear a bit superficial...nevertheless here is a repost with another bit of LCE applied. I also toned down the red glow from light pollution, and resized to 800px to save at a higher IQ setting.
:t3

Andrew Aveley
05-27-2012, 02:40 AM
Yeah but.........:Whoa!: lol , quite like the colours in the original. I think that with lower ISO here your IQ would have been a lot better and more appealing. Sacrifice of DR is something that I personally think with these nocturnal shots for IQ is my take on the end result . That is of course because i don't get that high with my ISO :eek3: but yeah , cool idea and i am sure that doing this out in the middle of nowhere would let the milky-way explode in the frame. Maybe when you venture south we can argue this over a 'coldone' under the Karoo skys

Morkel Erasmus
05-27-2012, 03:35 AM
Yeah but......... lol , quite like the colours in the original. I think that with lower ISO here your IQ would have been a lot better and more appealing. Sacrifice of DR is something that I personally think with these nocturnal shots for IQ is my take on the end result . That is of course because i don't get that high with my ISO but yeah , cool idea and i am sure that doing this out in the middle of nowhere would let the milky-way explode in the frame. Maybe when you venture south we can argue this over a 'coldone' under the Karoo skys

I agree. I was trying to see what I can get with "pushing" the gear a bit away from my normal ISO-3200 setting for stars :e3. Of course I do have some with lower ISO and f2.8...
That cold one under a Sutherland sky is a sure date! :5

Roger Clark
05-27-2012, 11:56 AM
Yeah but.........:Whoa!: lol , quite like the colours in the original. I think that with lower ISO here your IQ would have been a lot better and more appealing. Sacrifice of DR is something that I personally think with these nocturnal shots for IQ is my take on the end result . That is of course because i don't get that high with my ISO :eek3: but yeah , cool idea and i am sure that doing this out in the middle of nowhere would let the milky-way explode in the frame. Maybe when you venture south we can argue this over a 'coldone' under the Karoo skys

A couple of notes.

ISO does not change sensitivity. For example, 20 seconds at f/4 and ISO 3200 captures the same number of photons as 20 seconds at f/4 and ISO 12,800. But you are correct that the lower ISO will have more dynamic range (in fact 2 stops more at ISO 3200 versus 12800). As long as the camera does not have banding issues (the Nikons are very good in this regard), exposing at ISO 1600 or 3200 and lifting in post processing can make for more dynamic range and better star colors. All Canon cameras I have studied have banding issues and I would not use them for night time star images at less than about ISO 1600. I use my 5DII at ISO 3200. The 1DIV has very low banding compared to other Canon cameras (but not as low as cameras like the Nikon D800) and I use the 1DIV at ISO 1600 for night imaging. This (ISO) is only for dynamic range as the amount of light captured is only a function of exposure time and lens aperture.

The other method to improve signal-to-noise is to take multiple exposures, align them and stack them. So Morkel, if you have several exposures at the same f/stop, try adding them together (after aligning).

Roger

Vivaldo Damilano
05-29-2012, 11:27 AM
I would say excellent for such high ISO, I would have used ISO 3200 though, better performance and less noise. Still great shot Morkel, love it.

Grady Weed
05-29-2012, 05:20 PM
Whatever the settings were, the milky way sky scenes are always just spectacular. We are so small when compared to the universe. i love the night sky, your image makes me envious. We just do not get enough dark sky here in my part of Maine to do it justice. Thanks for sharing this nice image.

Colin Knight
05-29-2012, 07:33 PM
Morkel...not much for reposts but I'm fascinated with these types of images. I thought I would give that light pollution in your first post a quick try. I spent about 2 minutes on it, enough to be pretty sure with some time it could be completely eliminated.

113553

Andrew McLachlan
06-02-2012, 09:48 PM
Hi Morkel, an interesting read for a lovely capture. I'll have to try some of these night time images when my D800 arrives.

Roger Clark
06-02-2012, 10:21 PM
Colin.
I like your repost. Nice job eliminated most of the light pollution.

Roger

Colin Knight
06-03-2012, 03:07 AM
Thanks Roger, a quick attempt, definitely more could be done.