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Nightscape from Mt Lassen, CA

I have some experience doing Astro Photography with a CCD camera and telescope but ever since I saw a spectacular nightscape photograph from Zion national park, I've wanted to learn how to do that. I couldn't understand how one could capture so much detail in the Milkyway galaxy and at the same time not blur the foreground or horizon.  I assumed you had to do long exposures (i.e. several minutes or more) to get the galaxy detail, of course, I was basing this on using a 4" F7 refractor or my F4-5.6 kit lens with my Canon DSLR, where that was the case.

I now understand the need for a fast lens and I just purchased a Sigma 20mm F1.8 for this task. I think I already understand most of the basics for doing a nightscape and armed with a fast lens the most important thing I need to learn is the postprocessing to draw out the detail of the night sky. I've already tested out the lens in my backyard.  It's certainly not a dark sky site (medium size city light pollution and several street lights) and I don't have anything special in the way of a foreground but I can already tell that this lens will make a huge difference.  I've uploaded a raw photo of simply a 15 second exposure, which even without any processing shows more promise then previous 1 - 2 minute exposures with tracking by mounting my camera on my telescope; although, I clearly need to improve the focus (usually I connect my camera to my laptop for a bigger image and this was just using the lcd screen - my eyes aren't good enough these days!).

I'm sure I will pick up many other techniques from this workshop and hopefully some ideas on how to be creative and add some unique touches.  I don't see how stacking the light frames is going to be possible without blurring the foreground or horizon but I'm interested in seeing if my understanding of how to preprocess with dark and flat frames can improve nightscape images.

So, I'm off and running with this project and excited about the prospects from this Skillshare workshop.  My wife and I do a lot of camping in beautiful places and bringing gear for nightscapes is a lot easier than for deepspace Astro Photography.

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Update 10/29/13

I just had some clear skies and a chance to redo my first photo but now getting the focus down.  I find it a big help to connect my dslr to my laptop with a camera specific usb cable and focus using Canon EOS utility since I can then look at a full-sized photo on my laptop and zoom in 100 - 200% to fine tune focus.  Here's a 15 sec photo of the Cygnus region from my backyard for which it's a little easier to see how the focus turned out as opposed to a 25 - 30 sec exposure at higher iso which will be washed out. The next photo is a 30sec exposure at 3200 ISO as I understand that despite being greatly washed out this is more what we are after with our raw photo and I'm hoping I'll learn in a later video how to do the post processing.  These are on the red side since I modified my dslr by removing the stock canon filter so I wouldn't lose IR sensitivity to help with picking up more nebulosity.

15 sec, 1600ISO

30sec, 3200ISO

Hopefully, weather permitting, I'll get to Mt Lassen area to collect some photos that will turn into my final project and I'll post some raw images and my attempts at post processing.

 

 Update 11/14/2013

Change of plans. An unexpected snow in Mt Lassen closed the road giving access to the any of the area near the mountain.  Since I only had two days before heading out of town for almost two weeks, I looked for a close dark sky site using the Dark Sky app.  This wasn't at elevation but it was in a gray/black area.  Unfortunately, we were at a campground and had to deal with a bathroom light that I was surprised to find illuminated a significant part of the foreground.  Nonetheless, the Galactic center came out nicely and we had an enjoyable camping experience with a good bottle of wine after the photo shoot.

 

Location: Black Butte Reservoir - about 20 miles west of Orland, CA

Date: 10/31/2013  Time: between 7:30 - 8:30PM

Moon: Wanning crescent, 27 days old, 7.4 percent illuminated but not an issue as it set at 3:58PM.

Milky Way: +/- 5 degrees from SW; easily visible by naked eye during shots and identifiable ahead of time from Venus.

Accessories: 18' red led rope light with remote dimmer & on/off, small red, blue and white led keychain lights, red led headlamp and a bright white led flashlight.  SkySafai Pro on my iPad for timing the shoot ahead of time and help in setting up ahead of time.  Had a remote switch for triggering exposures but ended up just using the 2sec and 10sec delay.

Camera: Canon EOS 70D with a Sigma 20mm F1.8 lens. Gitzo tripod and head.

 

All the photos below were 30sec exposures, ISO 2500, F1.8.

1 sec of red rope light making a circle around us.  Tried to darken the effect of the bathroom light below us as best possible.  Zooming in I can now see that I have some star trailing and should have shortened to probably 20sec.  My favorite of night.

 

By tweeking out more detail of the Milky Way I ended up greatly enlarging Venus, which hadn't yet sunk below the horizon.  I don't know Photoshop well enough to know how to deal with this.  Also, we decided we didn't like painting us with too much red light and again used only about 1 - 2 sec of red rope lighting.

So, the photo below is a silohette with no artificial lighting.  I like this affect but feel I didn't do as good a job with post processing.

This was an early picture when I was waiting for it too get darker and decided to give "painting" a try.  This is my wife Renda - she didn't like the photos with brighter foreground subjects but except for the over-done Venus I really like this one.

The photos above are what I guess I would call "final" versions where I gave my best shot at the post processing steps.  Below are some raw photos that I didn't post process because for various reasons they didn't turn out that well.

Wish this one wasn't blurry because I must have moved because I like how we tried to get the Galactic center to come up between us.  The strange blue light by our hands is the remote switch for turning off the rope light encircling us.

Looks like the "kiss" is a common idea for this; too bad this one is blurry as well.

Had to give this a try.

PS

I forgot to mention my attempt at applying some astrophotography techniques or preprocessing with a master dark and possibly a master flat. Unfortunately, the AP program I do this in leaves the image in a heavily color-casted state after I debayer the raw image to import into Lightroom.  I can't seem to correct this to get a photo in a similar enough state to make a comparison.  I suspect that with wide field shots such as these, this added effort to reduce noise or correct for inherent gradients isn't necessary and the newer dslr's seem to have very little noise even at higher ISO settings.  However, my camera supports multiple exposure processing for taking up to 9 images and will average them for you.  So, I will give this a try letting the camera produce a 9-image master dark (and master flat) and then do the preprocessing in Photoshop myself.  I know how to use layers to subtract the master dark but I don't know if there is a way to "divide" the master flat.  Again, I doubt this really matters compared to getting better at getting the best raw images and improving on post processing.

I enjoyed this class.  Thanks!

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