Plan, Shoot, and Edit the Milky Way

[KmH]

 

[dennybeall]

Wondered how that was done, thanks for linking to those.

 

[zombiesniper111 11]

Good tutorials.
Thank you only editing the photo. I was afraid I'd look up at tonights sky and it would be completely foreign to me.

 

[TCampbell]

Those were good tutorials. He was fairly thorough on that first tutorial -- that's a good find (we must teach him how to pronounce "stell-AIR-ee-um".)

Also, if you have an iPhone or iPad, check out PhotoPills (PhotoPills | Shoot legendary photos) which works much like The Photographers Ephemeris -- except that it also includes the Milky Way. I don't know of an equivalent Android app... although I heavily use Sky Safari 5 (which runs on both iOS and Android) and is an outstanding astronomy app.

Focus:

In the first tutorial he mentions just setting focus to the "infinity" mark or pre-focusing the camera before heading out... that probably won't work out very well. To get sharp stars, I hardly have to move the focus ring and see quite a difference between "focused" and "not quite focused".

I must confess... when I first started, I used the live-view screen to focus until it looked sharp. I took my images. I inspected them to make sure they still looked good (they did). Once I arrived home I imported them into the computer and discovered they were all irritatingly soft -- just enough to drive you nuts but not enough so you'd notice on a tiny 3" camera screen (all that time... wasted.)

So now my technique is to use the digital zoom feature of the live-view to take it to max magnification (10x on my camera) and then _very_ carefully rotate the focus ring while watching the stars until I minimize their size. On longer lenses and telescopes I use a Bahtinov focusing mask (it causes all points of light to throw diffraction spikes which only converge in a common center point if the lens is focused.)

If the camera supports exposure simulation in live-view (I believe all Canon and Sony cameras do, but I think most Nikon cameras do not. I know the D810a does support it - but that's an astrophotography camera.) then you can crank up the ISO and dial in a 30 second exposure and the live-view will amp up the brightness on those stars making them easier to focus. Once focused you can return to more reasonable exposure settings before taking the shots.

Other comments...

Vignetting:

In the first video... if you notice the "out of the camera" shot doesn't have much (initial) vignetting. But after he stretches the histogram to tease out more detail you suddenly see fairly extreme vignetting. This is because when you stretch the histogram things that were just subtle differences suddenly become much more noticeable. Normally that's a good thing... except when it's vignetting. Lightroom does have a feature that lets you un-vignette the image. This should work fairly well for DSLR astrophotos taken with camera lenses. With telescopes it doesn't work as well because the vignetting usually isn't centered (so we shoot "flats" -- flat panel images of nothing with the sole purposes of letting the computer detect the vignetting so that it can be properly subtracted from the image.)

Background neutralization (white balance):

Before stretching the image, it's a good idea to neutralize the background. In Lightroom's "Develop" module, if you float your mouse around over any part of the sky that represents true "blackness of space" background (no stars, no milky way... an area of the image that should (but probably isn't) plain black sky... do this while looking at the Histogram in the upper-right corner of the Lightroom window. You should see RGB values being displayed just below the histogram (and these will change as you slide the mouse around). You want these pixel values to indicate at neutral background... e.g. an RGB value of, say, 20, 20, 20 would be good. If you see something like 20, 20, 12 then you'll have some muddy looking red/green sky background that won't be as attractive. Now that you know what to look for you can white balance the image to neutralize the background. (The white balance tool actually will let you click on the dark background.) Do this before stretching the histogram and if you happen to prefer a color tinted sky you can always do that later (after the stretch) but at least you started out with better data.