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Diane Miller
08-29-2014, 11:58 PM
From 8000 ft in the mountains in the central Sierra Nevada, at the dark of the moon, the night sky is awesome. I made the trek just to shoot this.

I've gotten an Astrotrac, a device that lets the camera follow the motion of the earth, so I can shoot longer exposures without star trails. For reasons I'm still digesting, the astrophotographers say to keep the ISO at 1600, for minimizing some of the components of noise. I shot a series of exposures to stack in astronomy software, but haven't had time to master it yet. A first quick attempt didn't yield much improvement over what I can do in LR with one exposure, which this is. But it certainly is an improvement over the ones I shot at ISO 3200 or 6400 and 10-15 seconds, which just barely keeps the stars from trailing to my standards.

We can't see color in dim light, but the camera can, which I think is pretty cool!

Canon 5D3, 17mm TS-E (in neutral position), f/4, ISO 1600, 90 sec.

Don Railton
08-30-2014, 11:19 PM
Hi Diane, I have not done any Astro photography, but I very much like what you have here. It always amazes me what the camera can see that we cannot. This is an area I would like to get into, and plan to have a try when we go back to the farm in a few weeks. Perth was called the 'city of lights' by one of the early astronauts in a Mercury spacecraft and in the one attempt I made was sunk by the amount of surrounding light (I think anyway, could have been just me..) Some of the other astro images I have seen have a little more colour than this, do you think it might be common to push the Saturation slider up a little in this sort of photography??

regards

DON

Diane Miller
08-31-2014, 01:36 AM
I see a lot of Milky Way pictures where people really overcook them. They are all single shots at high ISO and long enough that there would be some star trailing if seen up close, and I have a feeling they are ugly viewed at 100%. Since we can't see color at night, it's hard to know what is "real" but with tracking I was able to get a fairly clean exposure so I wanted to keep adjustments minimal.

But maybe more saturation would be OK -- I'm new at this. I have seen pictures of nebulas where a surprising amount of color has been pulled out, but I don't think it's from saturation as much as it is from restoring contrast to a naturally flat capture. The deep sky stuff is processed with special software that I'm just beginning to try to get my head around.

Don Railton
08-31-2014, 03:46 AM
Hi Diane.. To be clear, I wasn't thinking you needed to increase the saturation, I was simply trying to understand how different people might process/interpret something as you put it "we cannot see". In my one attempt at this sort of Star Photography I got a miserable image that got the delete treatment pronto. You have put a peg in the ground for me to aim for.. I have an interest in doing better because I have a wedding image in mind for whenever it happens with my Daughter (at the farm) and I am just trying to line up the ducks so this image happens to my satisfaction with minimal effort on the night.

best regards

DON

Diane Miller
08-31-2014, 03:13 PM
There's a lot of information about various night sky shots on the internet. You'll want to build a large foundation of practice, even if conditions aren't ideal, if you want to be able to do a wedding shot.

There is a helpful e-book by Alister Benn.

Don Railton
08-31-2014, 06:55 PM
Thanks Diane..

Miguel Palaviccini
09-01-2014, 04:24 PM
Gorgeous Diane! Would have loved to see this MW with a foreground element to really ground the image.

On a side note, I learned some astrophotography from Jesse Summers and he started with a base exposure of 30", ISO 3200, f/2.8. I don't notice much noise with the 5D3 and really haven't seen any star trails at 16 mm. That said, there are several ways to shoot the milky way and I don't pixel peep to look for star trails (so I'm sure they could be there - if ever just slightly)

Andrew McLachlan
09-01-2014, 06:43 PM
Hi Diane, I have never tried any night photography yet so can't comment on that aspect of this, but what you captured is quite nice and as you say 'not over-cooked.' I am thinking it may benefit from a smidge more on the bottom, but that is an easy fix if you are so inclined to do so. Can't wait to see more of these night images!!!

Diane Miller
09-01-2014, 07:05 PM
Thanks, guys! I'll use base images such as this one to composite FG elements, so they were minimized here. I can easily add a little more at the bottom, though. There is another spot a little farther up the road with less FG but somebody had it staked out. I'll shoot there next time, trying for Andromeda after the Milky Way, and doing star trails with a second camera at the same time. That will be an all-nighter.

With star tracking, FG elements will blur (and without it, stars will blur). My best wide-angle lens for minimal corner distortion is this one, but it's f/4. (I'm condemned to be a pixel-peeper!) So I can do way better with tracking, both for getting point stars and low noise.

Don Lacy
09-05-2014, 07:58 AM
HI Diane, Wonderful image astro photography is on my to do list
[QUOTE]My best wide-angle lens for minimal corner distortion is this one, but it's f/4. (I'm condemned to be a pixel-peeper!)/QUOTE]
Have you considered the Sigma 35 mm 1.4 for this type of photography here is a good discussion on its merits for night imaging http://www.naturescapes.net/forums/viewtopic.php?f=57&t=235065&p=2244661&hilit=sigma+35+mm,+#p2244661

Diane Miller
09-05-2014, 09:41 AM
Hi Don,

I've heard it's wonderful, but I'd have to mosaic for wide angles. With tracking I can get plenty of light with the 17mm f/4, which has excellent correction for coma and other issues. And I can stack a set of exposures to minimize noise. Shooting a set over an hour or so, I can remove the ones with light trails and have a good number left. (My favorite Milky Way spot is on a much-used approach route to the San Francisco bay area airports.) I'm not that concerned about including some of the landscape -- at least at this point. I can't do that with tracking, as it moves.

After the wide-angle Milky Way, I'm going to about 300mm plus, for "deep sky" objects. I haven't found much to shoot in between.

Go for it -- would love to see what you get!

Morkel Erasmus
09-06-2014, 06:13 PM
I know we sit on different ends of the fire when it comes to how much processing to do on the milky way and the sky colours etc, Diane...:w3...but I think a 5-10% saturation boost would make a big difference here without straying from your intent/vision. I like the simplicity of the base/bottom but it does look slightly soft to me - how does the tracking system ensure a sharp silhouette at the bottom? :e3

Diane Miller
09-06-2014, 06:29 PM
I wouldn't object to a little more saturation. Since we can't see the color (except for a hint of the light pollution on the horizon) it's all a guess.

The silhouetted horizon is slightly soft because the tracker follows the motion of the stars, and this was a 90 sec exposure. Over the hour that I shot sequential exposures (for noise reduction) the horizon moved a surprising amount, rotating CCW. (And the stars were eerily in exactly the same position in the frame.) I just presented this one frame as it was, but ultimately I'll process sets like this for NR and fine alignment and remove (or shoot without) any FG and composite in sharp FG's. That way I have the best of both worlds.

Next time out I'll hope to shoot from a higher vantage point with a much more distant horizon that fades into atmospheric haze. Somebody was camping there this last time.