Black Pool kissed by the Milky Way

[Uilleann]

In Yellowstone's West Thumb Geyser Basin, several thermal features are located in a relatively small area on the shores of Yellowstone Lake. One of my favorites is Black Pool as it lines up very well with the Mily Way core in the summer and fall. A fellow photographer took a photo here years ago, and seeing it was also an inspiration to get back into photography, and nightscapes in particular once again myself.

Last Saturday night was as peaceful as anyone could wish for. And the skies, reflected in perfectly still water, did not dissapoint!

[drk]

Question for Uilleann:
I live in a light-"polluted" area, and I can't see the edge-on view of the galaxy nearly that obviously. It's so faint as to be almost imagined, if seen at all.

Is your photograph so "exposure enhanced" as to make it that visible, or does it look like that? If so, how long is the shutter open, if that's the way it works?

[Steve Machol]

Can't speak for Uilleann but when I shoot the Milky Way I generally leave the shutter open for between 20-30 seconds, depending on what ISO I'm shooting at and how dark the sky is.

[mervinek]

Beautiful!

[Uilleann]

Question for Uilleann:
I live in a light-"polluted" area, and I can't see the edge-on view of the galaxy nearly that obviously. It's so faint as to be almost imagined, if seen at all.

Is your photograph so "exposure enhanced" as to make it that visible, or does it look like that? If so, how long is the shutter open, if that's the way it works?

Yep. Interestingly, that's precisely the same way that even the Hubble and J Webb scopes work. In their cases, often hours long exposures. The human eye doesn't pick up photons the same way a camera sensor does of course (without getting into all the characteristics we all know of rods vs cones in low light, scotopic / mesopic / photopic visual perceptions etc of course). But a LOT has to do with the darkness of the location as well. I can't get anything even remotely close to this sort of image from Salt Lake City. I have to travel more than an hour away before skies start to get dark enough to even attempt this, and as you probably know, Yellowstone/Teton are both farther from major population centers than that as well.

In this case, the single exposure was 13 seconds (if memory serves here - I usually shoot between 8-15 seconds max for shots like this) at f/2.2 - or fairly wide open. You need "fast" glass (low f numbers, equating to wide open apertures) to really work well on shots like this. Timing is limited by the speed of rotation of the earth, and anything longer than a few seconds starts to "trail" the stars, instead of keeping them as pinpoint dots. (Sometimes the trailing is desireable depending on the type of photo you're trying to create.) In a true dark sky site like this, you can easily see the Milky Way naked eye, including brighter and darker starfields, along with the much darker dust lanes near the core (dark horse nebula etc). They're not as colorful as in photographs, but our rods do quite well at seeing the overall structure.

I'll see if I can find a photo that more closely matches what the eye percieves in a place like this at night!

Can't speak for Uilleann but when I shoot the Milky Way I generally leave the shutter open for between 20-30 seconds, depending on what ISO I'm shooting at and how dark the sky is.

Steve you've got it right! Shutter speed will depend on focal length as well - with wider lenses allowing longer exposures without trailing, and narrower necessitating shorter snaps. With my 24mm lens, and the pixel pitch of my camera's sensor, about the longest I can go without any noticeable trailing is 8 seconds or so. Any longer, and with any sort of magnification, you start to see little footballs, or linear streaks of light, instead of dots. A 14mm lens can get you up into the mid tees, or even 20 seconds without trails. While a 35-50mm lens will require a much shorter 3-5 second exposure to keep the stars as points.

[Steve Machol]

Steve you've got it right! Shutter speed will depend on focal length as well - with wider lenses allowing longer exposures without trailing, and narrower necessitating shorter snaps. With my 24mm lens, and the pixel pitch of my camera's sensor, about the longest I can go without any noticeable trailing is 8 seconds or so. Any longer, and with any sort of magnification, you start to see little footballs, or linear streaks of light, instead of dots. A 14mm lens can get you up into the mid tees, or even 20 seconds without trails. While a 35-50mm lens will require a much shorter 3-5 second exposure to keep the stars as points.

Have you considered checking out the 14mm Rokinon lens? It's relatively inexpensive (around $300) and it's been a wonderful lens for night sky shots for me.

[Uilleann]

Have you considered checking out the 14mm Rokinon lens? It's relatively inexpensive (around $300) and it's been a wonderful lens for night sky shots for me.

I have as a matter of fact! I'm really interested in a wider fast prime for some compositions, and that was near the top of my list for sure! May try to rent before purchasing, but if I find a good deal on a clean used one...might pull the trigger anyway!