Night Sky - Milky Way Photography.

Last night I finally drove about 50 km north of the city to find a location that would be dark enough to try and photograph the Milky Way. It was my first time doing this and it was somewhat successful, but also opened up a bunch of new questions.   I have read a bunch of articles online about it, but still am unsure in a few areas. FWIW, I am using a Nikon D810 with a Sigma 24-35 f2. My hopes are to get an Irix 15mm f2.4 at some point for this.

1) I am realizing that just putting the manual focus on the infinity symbol is not accurate enough. So how do you manually focus the lens to be as sharp as possible on the stars? 

2) Do most of you that do this use some kind of star tracking device? If so, what are some that I could look into that are not too expensive?

3) Using "Auto" white balance I found the images too be too orange or warm for what it really looked like. Yes I can fix that in RAW conversion, but was wondering if most people set a manual white balance, and if so, what K do you set it at? Somewhere between 4000k and 4400k seemed to be reasonable. I also found the auto white balance to be all over the map from one frame to another.

4) I found it extremely difficult to level the horizon by using the viewfinder (like nearly impossible) do people use Live View for this? Is there a technique for this? How do you frame your image when it is so dark and hard to see?

5) Even at 20 to 30 second exposures, there is a noticeable amount of blur and Earth rotational movement. Can I assume that this would be less noticeable with a 14 or 15mm lens than with the 24mm?

6) Lastly, I see that many Milky Way or night sky images are stacks of 10 or more files. So what is done differently with each frame to make this stack a better image? Is it different exposures like HDR? Do you using stacking software like Photoshop or Helicon Focus, or is there some special sky stacking software?

Now comes the task of finding better locations that offer nice scenic images and are far enough away from city lights to be dark enough.

Tim,

what several tutorials I've watched suggest for focussing is to focus on a distant object (infinity) in daylight then put a piece of tape on the lens for when it's dark.

E.J. wrote something a while back saying that at our latitude shutter speeds greater than 15 seconds will introduce rotational movement. I don't remember when I read it but perhaps E.J. will advise you on

I found this tutorial to be quite enlightening. It's Lightroom but should be adapted to CS6.

Cheers

This site has a lot of info. You may remember him from the forums.

http://www.clarkvision.com

http://www.clarkvision.com/articles/nightscapes/

Joe

1. Just like on your super tele, the lens will focus past infinity so you have to find infinity focus.  There are many ways of doing it.  Some cameras have enough gain in Live View to be able to focus in live view, sometimes you can find a distant light.  You can always lay a flashlight on the ground some distance away and focus on that.

2.  Some do, some don't.  The beauty of a tracking device is that you can take much longer exposures and therefore use much lower ISO resulting in less noise.  The downside is that any ground based objects in the frame will now blur meaning you have to take a separate untracked shot for the ground.  The Polarie Vixen is a relatively affordable one but there are more accurate and more expensive ones that have higher load capacity.  See my picture above...

3. You most definitely do not want Auto WB (I suggest one should never use auto WB for anything but that's a different topic).  4000 is fine, I just use daylight and correct to whatever I want later in post.  BTW, an astro filter does a great job of filtering out man made wavelengths of light with almost no loss of light.  the Breakthrough Filters one is exceptional.

4. Use the level in you camera, almost all of them have it or use a bubble level in the hot shoe.

5.  At your latitude a 500/FL formula should give you OK results for most reproduction sizes and 400/FL should give you excellent results.  As you go farther south you need to go shorter and shorter since the angular velocity of the Earth increases as you get closer to the equator.  At 24mm, 20 seconds is pushing the limits.  I would limit it to 15 or 16 seconds.  At 15mm you should be able to go to 25 seconds or maybe a little more.

6.  The main reason for stacking them is to average out random shot noise.  I do this and use a program called Starry Landscape Stacker but this is Mac only (it's the main reason I keep one Mac running).  There are other such programs that are platform agnostic.

Thanks guys

EJ . . . . . would that Polarie Vixen be able to handle a 300 f4 PF, or a 200-500 f5.6? Or would I need a larger one for that?  I would like to try other subjects like Andromeda Galaxy and nebulae.

I typically never use Auto WB for my shooting, but since this was totally new to me and there were no WB settings that fit the situation, I went with Auto. Next time I will use manual or daylight.

I had no idea my cameras have a level in them? . Where is it in/on the D810? I suppose I could use the level on my Gitzo as well, which I totally forgot about. You don't need these things for birds and macro  :shock:

Looks like a 15mm is on my future

I think it's limit is 6lb so I think the 200-500 with body will be too much but I think the 300PF should fit the weight limit.  The D810 has both a rear LCD level available as well as an in viewfinder level that you can assign to a button.  Virtually every camera made this decade has a level in it - even my old D7100 has it.  Nikon calls it Virtual Horizon and it's in the Tools Menu for rear LCD view or you can hit the info button and then cycle through the screens.  For in the viewfinder, you can assign it to either the front Pv button or Fn button via the custom functions Assign Buttons item.  See the manual.

It’s called “virtual horizon” and is on page 379, 347 and others (referenced)of the instruction manual.

Joe

Thanks guys. Never new about that one, will look it up right away

Just added Virtual Horizon to  My Menu and It works great!! Our last clear night for awhile tonight, so I am heading out of town to try things with your advice.

Tim Zurowski wrote:Just added Virtual Horizon to  My Menu and It works great!! Our last clear night for awhile tonight, so I am heading out of town to try things with your advice.

Hi Tim,

Never tried this type of shooting, but I came across this very short video the other day by chance.

Might be a tip or two that will help.



https://www.youtube.com/watch?v=_KiTiJo_R70

Here’s a link to another recent article that you may find of interest:

https://photographylife.com/landscapes/ ... hotography

Below that article you will find links to several others, including this one:

https://photographylife.com/landscapes/the-best-night-photography-lenses-for-nikon-cameras

Joe

Went out last night and tried it again, but unfortunately the location was not far enough away to avoid the city light pollution. I can say that EJ's suggestion for finding the focus point worked perfectly. Since Mars is so bright right now, I just zoomed in on Mars in Live View and manually focused to where it was sharp. It worked great!

So I have been looking at these tracking devices and still have a few questions. EJ, in the photo of your setup, what parts of that are not included with the Vixen Polarie? In other words, the Vixen costs $399, how many more parts are needed to use it and how much more will that cost?

I really want the option to be able to use up to a 500mm lens, so I have been looking at other tracking options. This Sky-Watcher seems to be a great price, gets good reviews has an 11lb load capacity. Anyone know about it?
https://www.bhphotovideo.com/c/product/ ... mount.html

Tim,

Your post couldn't come at a better time. I encountered this week surprisingly clear skies along the Oregon coast and tried my luck with a Sony a7rII and the Batis 25 mm F2.0 lens. I manually focused on Mars using "magnified live view" in the viewfinder. For the exposure (single - no tracking) I used the 400/25 rule EJ referenced (16 s), stopped down to F2.8 and adjusted the ISO (10,000 or 12,800) to ETTR. And yes, leveling the horizon with the camera built-in level was a lifesaver. And the viewfinder on the Sony a7rII was bright enough to help with the composition.

Frankly, I was positively surprised by the resulting photos - especially given the "stareater reputation" of the Sony a7rII (firmware 4.0) and that part of the frame included a coastal town with corresponding light pollution. But there are of course questions similar/in addition to the ones you rise:
- what is the best white balance? I left it on AWB and the camera chose ~3500 K (0 tint) which kind of looks right. But what is the true color of the night sky? It sure isn't black...
- noise at the high ISOs is of course an issue. Interestingly, processing the files in ACR by adjusting chroma and luminance noise manually gave much better results than running Nik's Define 2. In fact, the latter didn't seem to do much at all...
- what is the best strategy given the stareater issue with the Sony a7/9 cameras?

Thanks. And good luck! Best, Joerg

Edit: I did an upload of one of the images to my flickr account. Hope sharing the link here is allowed... Any feedback is welcome but especially suggestions how to improve... Thanks!

https://flic.kr/p/2aRPMvr

Tim Zurowski wrote:Went out last night and tried it again, but unfortunately the location was not far enough away to avoid the city light pollution. I can say that EJ's suggestion for finding the focus point worked perfectly. Since Mars is so bright right now, I just zoomed in on Mars in Live View and manually focused to where it was sharp. It worked great!

So I have been looking at these tracking devices and still have a few questions. EJ, in the photo of your setup, what parts of that are not included with the Vixen Polarie? In other words, the Vixen costs $399, how many more parts are needed to use it and how much more will that cost?

I really want the option to be able to use up to a 500mm lens, so I have been looking at other tracking options. This Sky-Watcher seems to be a great price, gets good reviews has an 11lb load capacity. Anyone know about it?  
https://www.bhphotovideo.com/c/product/ ... mount.html

The Polarie is just the white piece.  In my set-up you see an Arca Swiss p0-hybrid geared head below the Polarie and then the head from my MeFoto tripod mounted to the Polarie.  But like I said, it wouldn't work for your tele.  Also, for a tele you will want an actual alignment scope which is an optional add on to the Polarie.  Some others come with it. the basic Polarie just has an alignment sight which isn't that accurate - plenty accurate for lenses up to about 85mm and up to about 4 minute exposures but if you need to go longer either in focal length or time or both, you will need an alignment sight and one that compensates for the slight offset that the earth's center of rotation is from Polaris.  There is a little bit of drift that takes us farther and farther away from Polaris every year called axial precession.  A 500mm lens would definitely not be aligned well enough with an exact Polaris alignment - see Page 26 of the Polarie Owner's Manual:
http://wgnap.cymya.servertrust.com/v/vs ... Manual.pdf

Joerg Rockenberger wrote:Tim,

Your post couldn't come at a better time. I encountered this week surprisingly clear skies along the Oregon coast and tried my luck with a Sony a7rII and the Batis 25 mm F2.0 lens. I manually focused on Mars using "magnified live view" in the viewfinder. For the exposure (single - no tracking) I used the 400/25 rule EJ referenced (16 s), stopped down to F2.8 and adjusted the ISO (10,000 or 12,800) to ETTR. And yes, leveling the horizon with the camera built-in level was a lifesaver. And the viewfinder on the Sony a7rII was bright enough to help with the composition.

Frankly, I was positively surprised by the resulting photos - especially given the "stareater reputation" of the Sony a7rII (firmware 4.0) and that part of the frame included a coastal town with corresponding light pollution. But there are of course questions similar/in addition to the ones you rise:
- what is the best white balance? I left it on AWB and the camera chose ~3500 K (0 tint) which kind of looks right. But what is the true color of the night sky? It sure isn't black...
- noise at the high ISOs is of course an issue. Interestingly, processing the files in ACR by adjusting chroma and luminance noise manually gave much better results than running Nik's Define 2. In fact, the latter didn't seem to do much at all...
- what is the best strategy given the stareater issue with the Sony a7/9 cameras?

Thanks. And good luck! Best, Joerg

- Like I said in an earlier post, I just shoot at daylight WB and then adjust in post.  the one thing you do not want to do is to use AWB as the camera has no idea what to set itself too.  Probably around 4000 is a good starting point but it does depend on light pollution to some extent.  Also as I said, using an astro filter does an excellent job of removing earthbound sources from altering the color of the sky.
- I highly recommend taking 12 to 15 exposures and then using a stacking program that does a median sampling to eliminate the noise.  Starry Landscape Stacker for Mac is excellent and easy to use.  there are online videos on how to use it.
- Don't worry about the Star eater.  It really only effects extremely low magnitude stars.  Sure if you are doing documentary astro photography for scientific purposes then it's an issue but for landscape photography or artistic purposes it simply isn't a big issue.  That said, the newer cameras (a9 and a7 III series) are much better than the II.  I would recommend the a9 over the a7R II for this.

To both of you, I would also seek out you tube videos on astro shot processing of photos!  Basically just check out the videos on the Lonely Speck YouTube channel:
https://www.youtube.com/results?search_ ... nely+speck

Thanks EJ for the prompt and helpful feedback. Will look into your suggestions for sure. Best, Joerg

Joerg Rockenberger wrote:Thanks EJ for the prompt and helpful feedback. Will look into your suggestions for sure. Best, Joerg

Oh, one other thing, make sure you are shooting in uncompressed RAW on the Sony bodies. 

E.J. Peiker wrote:

Tim Zurowski wrote:Went out last night and tried it again, but unfortunately the location was not far enough away to avoid the city light pollution. I can say that EJ's suggestion for finding the focus point worked perfectly. Since Mars is so bright right now, I just zoomed in on Mars in Live View and manually focused to where it was sharp. It worked great!

So I have been looking at these tracking devices and still have a few questions. EJ, in the photo of your setup, what parts of that are not included with the Vixen Polarie? In other words, the Vixen costs $399, how many more parts are needed to use it and how much more will that cost?

I really want the option to be able to use up to a 500mm lens, so I have been looking at other tracking options. This Sky-Watcher seems to be a great price, gets good reviews has an 11lb load capacity. Anyone know about it?  
https://www.bhphotovideo.com/c/product/ ... mount.html

The Polarie is just the white piece.  In my set-up you see an Arca Swiss p0-hybrid geared head below the Polarie and then the head from my MeFoto tripod mounted to the Polarie.  But like I said, it wouldn't work for your tele.  Also, for a tele you will want an actual alignment scope which is an optional add on to the Polarie.  Some others come with it. the basic Polarie just has an alignment sight which isn't that accurate - plenty accurate for lenses up to about 85mm and up to about 4 minute exposures but if you need to go longer either in focal length or time or both, you will need an alignment sight and one that compensates for the slight offset that the earth's center of rotation is from Polaris.  There is a little bit of drift that takes us farther and farther away from Polaris every year called axial precession.  A 500mm lens would definitely not be aligned well enough with an exact Polaris alignment - see Page 26 of the Polarie Owner's Manual:
http://wgnap.cymya.servertrust.com/v/vs ... Manual.pdf

Thanks very much for the help EJ. So if I forget for now about using a 500mm and just work with 15mm to 50mm, will the Vixen Polarie that you have come with everything I would need to go out start shooting, or are there other components I would need to purchase to go with it? Naturally I have the tripod, ballhead, camera and lenses.

You need two heads along with the Tripod to use the Polarie or the Sky-Watcher you linked to. (BTW, If you get the Sky-Watcher for its higher weight limit, you'll want this one.    Skywatcher Photo Package

One of the heads could be a wedge like this one.    Skywatcher Wedge Base

I had picked up this one: iOptron since it came with the wedge and a small scope you help align with Polaris though it is has only 1/2 the weight limit of the Skywatcher.

EJ seems to be using a head he has around for the bottom head but really a wedge like the products I linked to or any Altitude/Azimuth head is ultimately easier since all you are trying to do with it is get the angle right so the wedge is pointed straight at the north (or south) pole in the sky and that requires just an up/down adjustment as well as a panning adjustment rather than a full movement system like a ball head or the like.

The second head can be a ball head or the like since you then need to point the camera at the section of sky you want to image.