Comment by dylan604 | Hacker News Reader

Comment by dylan604 | Hacker News Reader

I use this site frequently. Whenever I travel on assignment, I look up what the seeing will be like in that area. This sight quickly lets me know what kind of imagery will be possible. I then use other sites to get an actual seeing forecast that includes info like temperature, expected cloud coverage, wind speeds, moon phase, etc.

I recently visited Australia and New Zealand, and using this site I knew I was in for a treat at night.

Here's an example from NZ from a location that is represented by the first blue color after green: https://vimeo.com/246328898

Here's an example from Australia also in the same blue color on the map. However, this one starts while the moon is below horizon, and continues until the almost full moon gets pretty high in the sky to the point it looks like day light: https://vimeo.com/241600503

By comparison, here's a video where all of the footage was taken from a totally dark sky area of the map: https://vimeo.com/157779663 The difference from blue to black on the map is pretty significant.

I am quite the fan of this site. I'm not sure on the status of the site currently, but when I first started to use it, I believe the data was many years old at the time. Based on that, you can pretty much assume that if it is old data, then it will only have gotten brighter in any given area. Very few places take light pollution into consideration with new development.

That’s awesome! I lived most my life in nz and I still long for the stars there (living in the uk now).

I recently moved to a tiny village in the uk and the darkness is amazing. After years in London it still surprises me on a daily basis.

10 years ago I spent a month at sea and it will be hard to beat stargazing in the middle of the Atlantic Ocean :-)

Were the colors altered in your last video? Specifically the ones showing a very colorful sky?

Sorry for the naive question but I live in a city and despite having traveled a lot, it was mostly to cities as well. I cannot imagine such a sky in real life.

Wait... Stars are visible during the day with time-lapsed photography?

To be clear, no, that was not taken during the day. In that one clip from Australia, the light is 100% only from the nearly full moon. With a DSLR and a long exposure, that light will completely light up the area to the point that it looks like day light. The only thing to give away that it is not taken during the day are the stars being visible and the smoothness of the water. The smoothness of the water gives away the long exposure.

On a full moon in dark sky locations, it is possible to walk around without the need of a flashlight. Of course, you need to give your eyes time to adjust. It is definitely bright enough to cast shadows. I've even seen shadows cast from the light of the Milky Way on new moon nights. It is hard to believe how bright starlight can be.

I live in a "dark blue" area per the map, with a ~1h drive to absolute black. Mind you, I'm not sure I've noticed that much difference between my back yard and deep in the middle of Yellowstone.

Anyway, the thing that surprised me about long exposure DSLR dark photography is that you get pretty decent color rendition. For some reason I didn't expect that. You can very clearly see the different color temperature of the stars in Orion, and if you have a very dimly illuminated foreground as you mention, you see it in accurate full color. I guess I didn't expect it because human eyes don't register color in low light. DSLR sensors are doing it photon by photon through the Bayer filter..

Mmm..nope. The Milky Way cannot cast shadows visible to the human eye, it’s around magnitude 5. Even if it was possible (and it isn’t) there are many much brighter stars in the sky that would cast a stronger shadow. I saw a shadow cast from a meteor that was around -7 magnitude, so brighter than Venus, but I don’t think I ever saw a shadow cast by a star, even Sirius that is -1.6 if I recall correctly. Although I have never been in an area mapped as black, the darkest that I have been for star gazing was the dark green accordingly to the map.

Beautiful work!

Can you share the equipment you used to create these videos?

Thanks. I appreciate that. I use my handy Canon 5DmkII. I pretty much only shoot timelapse on that body, and it has over 250,000 shutter clicks. The lenses change depending on what I have with me. I've used Canon 24mm f/1.4, 35mm f/1.4, 20mm f/2.8, Rokinon 14mm T/1.5, 24mm T/1.5. I have a couple of sliders that I use for timelapse. One I hand built using an Arduino and different components on a 1000mm rail driven by a lead screw, and I also have a Syrp Genie I use with a cheap 24" sub $100 carbon fiber rail kit that fits nicely in my suitcase for trips involving checked luggage. I also have a collection of wired intervelometers. I also run MagicLantern firmware on the Canon. I use it for the ETTR abilities for handling bulb-ramping sunset/sunrise setups, but I will still use an external intervelometer for the shutter release. I have found that the MagicLantern intervelometer is not reliable, especially for intervals less than 5 seconds between shots. However, even at a 5 second setting, it will randomly take 2 shots in quick succession and then goes back to the desired interval. Never had an issue with an external controller.

edit: corrected one of the lens focal lengths

Thank you for the detailed reply! I want to try my hand at this at some point. Living in a city, I miss the stars.

This https://youtu.be/kNfRIkP0kgM is from Bellevue WA, less than 15 miles from Seattle, WA. Get a Hoya intenfifer filter, they’re about $50 and the results speak for them self https://www.lonelyspeck.com/hoya-intensifier-review-an-affor...

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