Guide to photographing the night sky and milky way

[YellowJersey]

I'm bored and have an urge to write.

 

 In this guide we'll cover the following to shoot the night sky and the milky way. I'll be focusing on trying to get best results, but don't worry if your gear isn't listed. Astrophotography is all about making compromises.

 

1) Camera body

2) Lens

3) The shoot

4) Processing

 

1) The Camera Body

 

 You can get decent results with just about any camera with a MFT sensor or bigger. For best results, you'll want full frame as the bigger sensors collect more light and produce less noise. The general rule is that you'll want a camera that excels in low light and has a lower resolution. So the best bodies are currently, imho, the Sony A7III, Nikon D5, and Canon 1DX mkII. However, sensors have become so good that virtually any full frame camera will give you more than usable results. I personally shoot with the 42MP A7rIII and I get fantastic results. So I think the low-resolution rule is becoming less relevant all the time.

 

 However, you'll also want to consider your medium. If you want to print big, more resolution is better (I did a 40x45 print of my last Milky Way shot and the 42MP was great). But, if you're just posting online then you can do just fine with even a 12MP sensor.

 The only cameras I wouldn't recommend shooting the night sky with are the A7, A7s, A7II, and A7sII. Unless you can get your hands on an A7s with original firmware, these cameras will suffer from the "star eater" phenomenon. Simply put, this occurs because overly aggressive noise removal software in the camera mistakes stars for noise and removes them from the image and there's no way to turn it off, at least without degrading your image quality. Fortunately, this problem has been fixed on the A7III and A7rIII (technically, the algorithm that caused the star eater is still there, but it's been tweaked so that it no longer deletes stars) and I expect the upcoming A7sIII will be fine as well.

 

 However, if you already have a camera (and chances are you do) don't worry, the lens is the most important part of the hardware. Don't worry if you don't have a full frame camera. I've seen some great shots with Fuji's APS-C line up. For MFT, you can add use a speedboster to help compensate for the smaller sensor

 

 

2) Lenses

 

 The general rule is that you want a fast  wide angle lens with minimal coma. By fast, I mean 2.8 or faster. By wide angle, I personally don't like to shoot at anything longer than 24mm, but I've seen people get fantastic results shooting at longer focal lengths. The reason for shooting wide is that the wider the focal length, the longer you can have the shutter open before visible star trails emerge from the movement of the stars across the sky due to the Earth's rotation. With a 15mm lens, you can easily do 30 seconds of exposure. With my 20mm lens, I shoot at 20 seconds. Coma is a type of astigmatism that causes stars to get smeared and look like they have wings instead of being fine points of light. Unfortunately, it can be tricky satisfying all these criteria (fast, wide, low/no coma). Usually, something's gotta give. There's no perfect lens for night sky photography.

 To see what I'm talking about with coma, see the image attached. www.lenstip.com tests for coma in its lens reviews and I highly recommend it when searching for a night sky lens.

 Lenses that are known to perform well are:
Tamron 15-30mm 2.8 VC (I used to shoot with this and it produced very good results)

Nikon 14-24 2.8

Zeiss Batis 18mm 2.8 (regarded as "the best" all around, but expensive)

Rokinon 14mm 2.8 (can suffer from quality control problems resulting in decentred lens elements leading to focus issues)

Among others...

 I personally shoot with a Tokina 20mm f/2. It doesn't have the best coma performance in the world and isn't quite as wide as I'd like it, but for my personal style, it balances everything well. I'd rather have the extra stop from an f/2 lens than get better coma with a 2.8 lens.

 

 

3) The Shoot

 You'll want to shoot on a tripod and get as far away from city lights as possible for best results. Set your camera to manual mode. Set your aperture to its widest and your ISO somewhere between 1600 and 12,800 (how high you can go without unacceptable image quality loss depends on your camera and your own personal tolerance for noise. I shoot at 6400.) You'll probably have to disable autofocus (though my old Canon 5DmkIII could actually autofocus on a particularly bright star using the Tamron 15-30mm). Fortunately, the image in live view makes manually focusing on the stars fairly easy. Caution: don't just set it to focus on infinity. Some lenses aren't properly calibrated and true infinity focus doesn't occur where it's marked on the lens. The Rokinon 14mm 2.8 is notorious for this.

 

 Shutter speed is going to depend on your lens. A good general rule is 500 / focal length (remember to multiply your focal length by 1.5 if you're shooting APS-C or by 2 if shooting MFT). Divide 500 by your focal length to get the longest shutter speed before star trails become visible. So for my 20mm lens, 500/20 = 25. (this rule doesn't work as well for high resolution sensors due to the smaller pixel size, hence why I shoot my 42MP camera at 20 seconds). Remember, the longer your shutter is open + the faster you lens is = more light hitting the sensor; that's what we want to maximise. If you want to take exposures above 30 seconds, then you can get a tracking mount, which will move the camera along with the rotation of the Earth, so you could take a 5 minute exposure without getting star trails. This really also means you don't need to have a super fast lens and could get away with an f/4 aperture. Many lenses have better coma performance when you stop the lens down, hence why a tracking mount can help compensate for the light lost by using a smaller aperture. Personally, I don't use a tracking mount, but I'd like to get one eventually.

 

 Take 10-20 exposures in a row for each composition you want. While you certainly can get a good shot with one exposure, for best results you'll want to stack multiple exposures to reduce the noise. This is because stacking averages the value of each pixel, which helps remove noise while preserving image quality.

 

4) Processing

 

We're primarily concerned with stacking multiple exposures here. If you only took one exposure, then just process how you see fit. But if you want the best results, I recommend this tutorial for stacking: https://www.youtube.com/watch?v=Rydg7JGTAbw   This tutorial presumes you have photoshop, but you can use other software (some of it free) to stack exposures.


Conclusion:

 

 Like I said in the beginning, shooting the night sky is all about making compromises in balancing sensor size, aperture, focal length, and most importantly your budget. You don't need the best gear in the world, though I would say that the lens is the most important part of the equation.

 

 

 

[Cereal5]

This is a great guide! I learned the quick and dirty version from a guy I met while on vacation in Maine. I shot a few shots of Mars that night. I have a Canon Rebel T7i (basic stuff I know), shot on a 18-35mm lens (set at 18), I think 200 ISO, 30 second shutter speed. Result:

 

Thats Mars directly below the moon and I think Saturn off to the right at the edge of the shot. The majority of my pictures are not of the night sky so who knows, this might look like poop lol. I like it though

[19_blackie_73]

good guide

for aps-c users, the sigma 18-35mm f1.8 ain't a bad choice either, though it's not the widest.

[D13H4RD]

I just want to say this.

 

If your camera still has a kit lens on it, you can still capture some pretty nice Milky Way shots. Obviously, they won't deliver as good a result as wide angle prime lenses with fast apertures, but it's a good starting point. 

 

This was shot on a Sony a6000 with the SELP1650 kit lens (known for being mediocre in comparison to the capabilities of the sensor) by Reddit user MadMonkeyNZ

ISO2000, f/3.5, 13s

 

 

 

[YellowJersey]

For the APS-C users, Laowa makes a 12mm 2.8 (18mm equivalent on APS-C) and a 9mm 2.8 (13.5mm equivalent on APS-C) that would be good choices. Both are manual focus only lenses, but to shoot the stars you're likely going to be manually focusing anyway.

 I learned all this the hard way. It's been almost 5 years since I started shooting the stars, and each time I figured out something new. I've only now got everything down and refined to the point where I feel like I'm producing print-worthy photos. Hopefully, you guys can skip some of the pain staking trial and error that I went through!

[Cereal5]

2 hours ago, YellowJersey said:

For the APS-C users, Laowa makes a 12mm 2.8 (18mm equivalent on APS-C) and a 9mm 2.8 (13.5mm equivalent on APS-C) that would be good choices. Both are manual focus only lenses, but to shoot the stars you're likely going to be manually focusing anyway.

 I learned all this the hard way. It's been almost 5 years since I started shooting the stars, and each time I figured out something new. I've only now got everything down and refined to the point where I feel like I'm producing print-worthy photos. Hopefully, you guys can skip some of the pain staking trial and error that I went through!

Like figuring out how to shoot in RAW lol yeah I figured that out don't worry

[YellowJersey]

3 hours ago, Cereal5 said:

Like figuring out how to shoot in RAW lol yeah I figured that out don't worry

RAW is best. Unfortunately, Sony doesn't offer a lossless compressed raw format, so my photos are around 85mb each. I really had to stock up on memory cards!

[D13H4RD]

14 minutes ago, YellowJersey said:

RAW is best. Unfortunately, Sony doesn't offer a lossless compressed raw format, so my photos are around 85mb each. I really had to stock up on memory cards!

You use those new UHS-II cards on your A7Riii? 

[YellowJersey]

13 hours ago, D13H4RD2L1V3 said:

You use those new UHS-II cards on your A7Riii? 

Yep. It doesn't make that much of a difference since one slot is UHS-I, so it bottle necks. I mostly shoot landscapes and such, so I don't need high frame rates or fast cards. I picked up the UHS-II cards just to future proof.

 

[xQubeZx]

On 10/22/2018 at 11:32 PM, YellowJersey said:

For the APS-C users, Laowa makes a 12mm 2.8 (18mm equivalent on APS-C) and a 9mm 2.8 (13.5mm equivalent on APS-C) that would be good choices. Both are manual focus only lenses, but to shoot the stars you're likely going to be manually focusing anyway.

 I learned all this the hard way. It's been almost 5 years since I started shooting the stars, and each time I figured out something new. I've only now got everything down and refined to the point where I feel like I'm producing print-worthy photos. Hopefully, you guys can skip some of the pain staking trial and error that I went through!

The Sigma 16mm f/1.4 is perfect for this too if you got an aps-c sensor. The 24mm equivilent is a little on the narrow side but you still get very good results imo, especielly if you stitch together a few shots. I’d also think the Samyang 12mm f/2 to be a good option too. 

[YellowJersey]

1 hour ago, xQubeZx said:

The Sigma 16mm f/1.4 is perfect for this too if you got an aps-c sensor. The 24mm equivilent is a little on the narrow side but you still get very good results imo, especielly if you stitch together a few shots. I’d also think the Samyang 12mm f/2 to be a good option too. 

 

 Also true.

 I usually take separate exposures for the sky and foreground. My last Milky Way photo ended up being 32 exposures altogether, 20 for the sky and 12 for the foreground. The final image ended up being 72MP!

[porina]

If you use a Canon APS-C body and a lens that does NOT have the EF-S protrusion into the mirror box area, there are light pollution filters you can get that fit in there. I have the Astronomik CLS filters, and they help with a lot of historic light pollution sources. They're probably not going to be effective against LED lighting though, so as they gain in popularity, the filter's usefulness may drop. If you do use one of these, it will wreck your white balance so you will have to compensate later.

 

I used one to good effect from my house. I live in a built up area, and to travel far enough away from it to not be a problem is not practical. I could only faintly pick it up, but without the filter it was impossible. I'll have to see if I can dig out the shot later.

 

Thinking more, the same company I think has also made similar filters for Canon EF cameras, but you have to engage mirror lock up before fitting the filter.

[YellowJersey]

6 hours ago, porina said:

If you use a Canon APS-C body and a lens that does NOT have the EF-S protrusion into the mirror box area, there are light pollution filters you can get that fit in there. I have the Astronomik CLS filters, and they help with a lot of historic light pollution sources. They're probably not going to be effective against LED lighting though, so as they gain in popularity, the filter's usefulness may drop. If you do use one of these, it will wreck your white balance so you will have to compensate later.

 

I used one to good effect from my house. I live in a built up area, and to travel far enough away from it to not be a problem is not practical. I could only faintly pick it up, but without the filter it was impossible. I'll have to see if I can dig out the shot later.

 

Thinking more, the same company I think has also made similar filters for Canon EF cameras, but you have to engage mirror lock up before fitting the filter.

I was all set to get one of those, then I switched to Sony. Oops. You can also get external filters. LonelySpeck offers a filter called PureNight, but it's a bit pricey.  https://www.lonelyspeck.com/purenight/ .

 

There's also a red intensifier filter that works well,but you lose 1/3 to 1/2 a stop of light that I use sometimes. https://www.lonelyspeck.com/hoya-intensifier-review-an-affordable-light-pollution-filter-for-astrophotography/

[porina]

19 minutes ago, YellowJersey said:

I was all set to get one of those, then I switched to Sony. Oops. You can also get external filters. LonelySpeck offers a filter called PureNight, but it's a bit pricey.  https://www.lonelyspeck.com/purenight/ .

At a simple level, filter cost is relative to filter size. Bigger filters are more expensive and you want to try and get the smallest filter that will do the job. If possible, that usually means placing it nearer the sensor, than the front of the optics.

 

I had wondered in the past if it would be possible to use an 8" SCT to do Ha solar imaging, so you need to have the rejection on the front in that use case to not melt stuff. An 8" filter would destroy my bank balance if it even exists. Strangely enough I never did try to use it in that way. There is solar film but that is more a strong ND and I wanted selective wavelength passband.

 

Anyway, back to original topic, I tried to find my earlier attempt at getting the milky way, and failed. I've narrowed down the timeframe to around 2009, so was a long time ago... think I'm overdue trying again.

[historicalpoultry]

Maybe another option for aps-c E-mount users would be the samyang 14mm 2.8 adapted via a speedbooster / focal reducer. I use the Nikon version with a Viltrox focal reducer and get great results for the price. I unfortunately don't have much time anymore to shoot the stars, but I managed the get this during the summer. This is probably the best shot I've taken of the milky way.

 

[YellowJersey]

For me, being in Western Canada, the best time to shoot the Milky Way is in May. I'm actually so far north that we don't get true astronomical twilight, so June/July aren't ideal. I've also got a window in August. Fortunately, there's a spot about 4 hours drive away that gets me really dark skies to the south with only a little bit of light pollution to be seen from the north. I usually only get one or two opportunities a year where the skies are clear, the moon isn't out, and I don't have to be up the next morning!

 

Two locations I recommend are Writing on Stone Provincial Park, Alberta and Great Sand Hills Provincial Park, Saskatchewan.

[D13H4RD]

On 10/24/2018 at 10:57 PM, xQubeZx said:

The Sigma 16mm f/1.4 is perfect for this too if you got an aps-c sensor. The 24mm equivilent is a little on the narrow side but you still get very good results imo, especielly if you stitch together a few shots. I’d also think the Samyang 12mm f/2 to be a good option too. 

Actually tried the latter for a lengthy period. It's a great wide-angle lens provided you can do manual focus (since the focal length is so wide, manual focus shouldn't be much of an issue).

 

Also tried the new 16mm Sigma DC DN f/1.4 at a photography exhibit just yesterday. I can't give my thoughts on it since my time with it was very short but I can say that on my a6000 at least, initial impressions are very strong, coming from a frequent Sigma 30mm f/1.4 DC DN user.

[xQubeZx]

On 10/28/2018 at 4:11 PM, D13H4RD2L1V3 said:

Actually tried the latter for a lengthy period. It's a great wide-angle lens provided you can do manual focus (since the focal length is so wide, manual focus shouldn't be much of an issue).

 

Also tried the new 16mm Sigma DC DN f/1.4 at a photography exhibit just yesterday. I can't give my thoughts on it since my time with it was very short but I can say that on my a6000 at least, initial impressions are very strong, coming from a frequent Sigma 30mm f/1.4 DC DN user.

I own the Sigma 16mm f/1.4 and I love it. It produces some really great images. However I’m not completley satisfied with the build quality considering mine is in for a repair at the moment. It broke in two pieces at the mount during a fall. Most of the body is in metal on it, but the mount is plastic and is only supported by 3 small screws into some pretty fragile plastic. There is no lens elements in this part, just a cable that provieds the communication between the lens and camera so really it should be an cheap repair I’m hoping. But still, I’m dissapointed they have such a weak spot in the lens and I’d imagine the force to break it as mine does not have to be so large. Will defentivly not trust it to handle as much abuse now atleast. A shame considering its great optical performance. 

[YellowJersey]

Can anyone recommend a good tracking mount? I was looking at the Sony 24mm 1.4 GM lens and thought that a tracking mount for 5 minute exposures would make more sense.

[porina]

On 11/4/2018 at 11:39 PM, YellowJersey said:

Can anyone recommend a good tracking mount? I was looking at the Sony 24mm 1.4 GM lens and thought that a tracking mount for 5 minute exposures would make more sense.

I have an Astrotrac TT320X but in a quick search it may be end of life now. It's a single axis motor, pre-programmed for the right tracking speed. At a minimum put a gear head on a tripod under it, and a ball head on top for the camera to get going. It has optional polar alignment scope, obviously important to get the tracking right.

 

It's been too long since I used it, but I don't think I really used beyond 30 second exposures at longer focal lengths. I never tried using such wide angles.

 

Other alternative is to get a full on equatorial mount. Maybe an EQ5 variants, they are ever popular. Basic one seems to be relatively low cost. I have the more heavy duty HEQ5 version and use that for my scopes. You will also need... forgot what they're called, dovetail bar? To adapt the scope mount to camera tripod mount thread.