Tag Archives: settings

The Elusive Milky Way – Capture an Image

I assume you already read part one of this article which describes a bit about what the Milky Way is and what times and seasons are best for photographing the cloud-like expanse of innumerable stars.  In this installment we describe the equipment and settings you will need.

Just Ahead: A Universe of Possibilities

f/2.8, ISO 3200, 30 seconds, post processed and combined with shots of the bridge that were lit with a spotlight.

Standard Capture

To get a passable or better image of the rather dim Milky Way you need:

  • A high performing low light camera (more on that in a moment)
  • A large aperture (f/2.8)
  • A wide angle lens. Ultra wide even.
  • A cool/cold night
  • As little city glow and moonlight* as possible – see below for an image taken in twilight
  • A solid tripod
  • Patience
  • To know where and when to look!

To get a recognizable Milky Way in a single frame, you’ll want to use somewhere between 2000 and 6400 ISO at f/2.8 or wider setting. That’s very high, and a wider aperture than many people have paid for.  You’ll also want to expose as long as you can before stars are streaking.  We recommend starting at 30 seconds, and reducing your exposure time if the streaking is objectionable. Below is an image taken when the rising moon was beginning to wash out the sky and this may be typical of attempting to capture the Milky Way in a less than ideally dark scenario.

Group Hug

Moonlight and Twilight begin to overwhelm the Milky Way in Alabama Hills, California; 30 seconds, ISO 3200, f/2.8, 17mm

Some image degradation is to expected. For example vignetting and coma are both more obvious at lower f/stops. Coma is a comma or “bird-wing” like appearance of stars near the corners of the image.  Both coma and vignetting can be overcome by stopping down the shot – but resist the temptation because stopping down means losing some or perhaps all of the wispy milky goodness that you are trying to capture. Exposing longer will only help if you have some special apparatus (see Tracked Capture below). Are you wondering why exposing longer does not solve the problem? We have tackled the issue in two different styles: a cheerful allegorical example, and a recent math savvy explication.

What will an image look like captured with 3200 ISO? It may look like the image on the left below which is “straight out of the camera” – but perhaps not for you as this image was taken in a VERY dark sky area in Nevada.  On the right is the same Milky Way with some simple processing we will describe in the next installment.

SOOTC (and not SOOTC) [C_039467]

What is a “High Performing” Camera?

I qualified my statement earlier by indicating a “high performing” camera is needed for a standard capture like those I’ve shown above.  Since it would be impossible to keep an up-to-date list of the current “high performing cameras,” let me instead point out a few characteristics common to all high performers:

  1. Recent generation (2 or 3 years since introduction) is preferable because technology has steadily improved.
  2. Large pixels (to collect more light).  A common measure of the pixel size is in microns. Generally this puts full frame cameras ahead of cropped cameras.
  3. High “ISO at Unity Gain” – this is a measurement of the efficiency of the sensor. There are two good sources for this information: the DxO Sensor Scores and ClarkVision’s (older) tables.
Don’t be fooled by the “highest ISO” setting advertised. That number is completely meaningless.
As of April 14, 2014, the highest performers are listed by manufacturer and in order of performance. E.g. the Nikon D3s is better than the D800 – though the difference is small. Indeed, the D800 excels in some categories over the D3s. Cropped cameras are shown in italics – note that there fewer of them and none of the crop cameras exceed their full frame siblings. The underlined Nikon cameras are literally the topmost performers over all cameras.

Nikon: Df, D3s, D4s, D600, D800E, D4, D610, D800, D700, D3, D3X, D3300, D5200, D7100, D5100, D7000, CoolPix A, D3200
Canon: 1Dx, 6D, 5D Mark III, 5D II, 1DS III, 1DS II, 5D, 1D III, 1D VI, 1D III, 1 D II
Sony: A7R, DSC-RX1R, RX1, A7, Alpha 99, Alpha 900, Alpha 850, A6000, Alpha 580, NEX-F3, NEX-C3, NEX-5N, NEX-3N, NEX-6, NEX-7
Leica: M Typ 240, X Vario
Phase One: P40 Plus, P65 Plus
Pentax: 645D, K-5 II, K-5 IIS, K5, K-50, K-01, K-30
FujiFilm: FinePix X100
Not in contention: any cameras by: Casio, Hasselblad, Konica Minolta, Mamiya, Nokia, Olympus, Panasonic, Ricoh, Samsung or Sigma.

The list above shows all cameras having a DxO Sports (low light) score of 1000 or higher.

Cameras like the Nikon D90, Canon 1D II N, Phase One IQ 180, Canon 1Ds, Nikon D3100 and Leica M9 fall just below this threshold and may also be suitable.  The first eight Nikon models outperform the Canon 1Dx, and after the 1DX is the Sony A7R. The Fujifilm just barely cracks the list in 43rd and last place.

If you want the camera to cost less than $2,000 USD your current top choices are: Nikon D610, Canon 6D, Sony A7, Sony Alpha 850 or the Nikon D3300.  If we were to make a recommendation, we’d recommend any of the full frame choices over the smaller sensor cameras.  Note that prices vary dramatically, and you may find used higher performing cameras for less than $2000.

Stacked Capture

A “stacked” capture is what you may need to resort to if your camera performance is not so spiffy.  The approach applies astrophotography techniques to create a lower-noise version of an image.  The technique requires MANY shots of the same view. However using this approach you will want to avoid having anything but sky in your photo. Terrestrial elements will make stacking the image tricky.

Urban Milky Way [C_036919-23PSavg]The image at the left is a stacked capture to illustrate the point, however it was done with a high performing camera and only 5 images.  A lower performing camera will require as many as 20 or so captures to combat the noise. The method is described in my a “Astrophotography 101” Webinar and details are walked through in Astrophotography 301.  On the other hand, this image was captured in a location where the Milky Way was quite faint – alongside 7 million people in the San Francisco Bay Area so there is hope even where the Milky Way can only faintly be seen.

Details about the stacking method appeared in an earlier column as well as in an an earlier webinar.

Tracked Capture

The last way to get a great shot of the Milky Way is to track the sky with an apparatus called an Equatorial Mount.  By tracking the sky at the rate of the earth’s rotation you can lengthen a 20 second capture to perhaps a 60 second one. You can also use several such captures to create a stunning “Stacked Capture”. Again, however, shots which include the land are a bit harder to pull off unless you resort to layering. What do you need to do a tracked capture? We cover that in detail in the Astrophotography 101 Webinar, but in short, you’ll want an Equatorial Mount of some sort – not an Altitude-Azimuth (aka Alt-Az) mount! A device that looks intriguing and not terribly expensive is the Polarie.

Once you get that image (or those images), you will no doubt want to tease the most pleasing photo you can out of your data. That is a topic we’ll cover in the next installment: Processing your Milky Way images.

Not Eclipsed!

I was crestfallen to see the weather reports. The last total eclipse of the moon visible from North America until 2014… and the weather everywhere within a reasonable 3-4 hour drive was predicted to be 90% clouds and worse. It seemed my eclipse was going to be eclipsed by cloud cover.

At about 9:15 PM, PST, however, I looked up and saw… THE MOON!  Sure, it was scintillating in a little sucker hole playing with me. But I decided to play along. I hastily hauled out the Canon 5D Mark II, the 70-200mm f/4 IS L lens, the 1.4x Telextender, and the Gitzo carbon fiber tripod. Why those? Because that’s what I found first.

My equipment was scattered about in my office still recovering from the wet weather we have had here in San Jose. Indeed, I did not find the batteries for my Canon 50D camera.

Photo 1: A Hole in the Sky

By the time I got set up, I realized that the moon would very soon be contacting the earth’s umbra (darkest part of the shadow). So I quickly got to shooting what I could. Never mind that it was cold and I was not dressed properly.  Soon enough the clouds would come and I could dart into the house to hurriedly collect what I was missing.  The first shot I got was with the moon in the earth’s penumbra (Photo 2).

Photo 2: Moon in Earth's Penumbra

Through various breaks in the clouds I was able to get photos from first umbra contact all the way up to totality. Including a serendipitous shot of an airplane headed, probably, to the San Francisco airport or some other place to the north west.

Photo 3: Airplane transits the partially eclipsed moon.

What settings did I use for these shots? f/7.1, ISO 200, and 1/400 of a second exposures. Why so fast? Because, my friends, the moon is BRIGHT. Even partially eclipsed, even already in earths penumbra it is a big bright object. Shooting the moon is a definitive case where your camera absolutely cannot get the right exposure if left to itself. A good exposure must be manually set. I arrived at my settings by a few quick trials. I started at about 1/200th at f/5.6 and noticed that I was getting some over exposed areas (on my LCD screen the overexposed pixels blink white). I then decreased the aperture and continued to tweak the focus.

I wanted the moon images to be as well exposed as possible – especially knowing that the thin clouds were going to dim the image. My goal was to get detail in the moon, I did not care about the clouds or stars. In fact it is impossible – except at a very slender crescent or during a total eclipse to get detail in the moon AND also show stars in the sky. Why? Because the moon is so, SO bright.

I definitely made a slew of mistakes. The most significant one is that I should have put the telephoto lens on my 50D body which is a 1.6 crop camera. Had I done that all my moon images would have been about twice the size of what I actually got. Not having my camera all packed away in my bag meant some lost opportunities here.

I also thought  that perhaps the 5D would have been a good choice to get a sequence of shots showing the progression of the eclipse. The idea was to get the moon in the bottom corner of the frame and take a series of shots as it moved to the upper left of the frame. This also did not work for several reasons. The first problem was that the cloud “holes” came at irregular intervals – so spreading them across the frame evenly was not going to happen. The second problem was purely my failure to correctly guess the path the moon would follow in the sky.  Had I been a little smarter I’d have switched lenses when I realized the timelapse path was not going to work. But instead I tried again a few times.  I also realized that when the eclipse was total, the moon was going to be quite dim and the superior high ISO performance of the 5D II was needed. For the totally eclipsed shot, the ISO was ramped all the way up to 1600 and the exposure dropped from 1/400 to 1/6 of a second. That is a HUGE difference. The slower exposure meant that details in the moon would be blurred and the stars at this telephoto range would become dashes rather than dots.

Photo 4: Nearly Total - With enough bright area left to form a halo in the clouds

All in all, I guess I’ll be better prepared for 2014 when the next total lunar eclipse is visible from North America.

Stacker’s Checklist

Note: Items in RED are suggestions and may be changed based on circumstances at the scene.

Site Selection

  • Sunrise, Sunset, Moonrise, Moonset and moon phase all known.
  • Safe area, travel paths known


  • Camera, tripod, release plate, camera batteries, memory card, lens, intervalometer + batteries, lens hood, rain protection, headlamp, flashlight/torch, and items for light painting.

On Site

  • Tripod set up – no leaning (center column should be vertical) – leg locks tightened.
  • Camera aimed, leveled.
  • Camera locked onto tripod. Head tightened.
  • Tripod weighted/secure and everything is wobble free. Keep the tripod low and out of the wind for best stability. Do not extend the center column.
  • Neck strap removed or secured to prevent wind throw. Intervalometer and any other cord, or wiring also secure. Velcro on the intervalometer and the tripod leg is a handy trick.
  • Save GPS coordinates and/or mark site with glow stick / other?

Camera Settings

  • Manual Mode, Bulb exposure
  • ISO 200  (varies but from 100 to 800)
  • Single Exposure
  • LCD brightness down
  • Image review time off
  • Record in RAW
  • White Balance = daylight (Auto not recommended)
  • Aperture f/4 (f/2.8 to f/7.1)
  • Auto focus OFF
  • Image stabilizer (vibration reduction) OFF
  • Long Exposure Noise Reduction OFF
  • Mirror Lockup OFF
  • Auto Exposure Bracketing OFF

Timer Setup & Test

  • No delay, length of exposure = 1:59 minutes (adjust based on conditions. A 2 minute total interval is a good starting point), interval = 1 second, Num exposures >= 120
  • Timer cabled to camera
  • Test sequence (lens cap on) – Verify that second shot starts before canceling.

Focus & Final Framing

  • Check image composition, field of view.
  • Set camera to Aperture priority mode (not needed if it is already dark)
  • Take several bracketed shots in daylight or twilight: if it is already dark take a high ISO “range finding” shot. E.g. 2000 ISO for 30 seconds.
  • Pixel peep and adjust focus until sharp.

Battery and Card Shuffle

  • Remove memory card and insert second card. Format new card in camera.
  • Take second set of bracketed shots.
  • Return camera to Manual/Bulb mode.
  • Turn off camera and remove battery.
  • Reinsert battery (or insert fresh battery).
  • Verify that all settings are correct (See Camera Settings, above)

Final Steps

  • Check for wobble. Start by lightly jostling the camera, tripod, center column and even walking around in the area to make sure no movement occurs.
  • Set DELAY on interval timer appropriately (at least 5 seconds).  Goal is to start and/or end in twilight.
  • Secure cables for timer, external batteries (and neck strap). Do not block battery or memory card access.
  • Switch to aperture priority mode (so that your manual settings do not change), take a single image and re-verify focus. If already dark, take a high-ISO range finding shot for this task.
  • Switch back to Manual/Bulb.
  • Verify all camera settings as described in Camera Settings
  • Start Timer and verify that the timer is running.
  • If practical wait for first two shots to complete.
  • NOTE: You can leave the lens cap on for the first few exposure to collect DARK frames.

My thanks to Mike W. for comments and improvements to this checklist.

Additional References