Table of Contents
astrophotographic landscapes of the Milky Way
see also:
source: low level lighting for astroscapes
Above: my astroscape from Craig's Hut using the Olympus mZD 8mm f/1.8 Pro fisheye lens
plan ahead
- if your aim is to get the most aesthetic imagery of the Milky Way, you need to not only have a clear sky with no moonlight or light pollution, but you need the Milky Way (in particular, the area around Sagittarius) to be in the part of the sky you will be shooting
- in the Southern Hemisphere, you will find it best with the Southern Cross at around the 5 o'clock position in the sky (the Southern Cross circles around the South Celestial Pole in the sky each day - for example, just before dawn in the Australian winter when it will be near the south-west horizon and you can place the Southern Cross in the far left of your scene assuming you will be doing a panoramic stitch of the arching Milky Way
- Sony a7S II full frame mirrorless camera firmware update 2.10 and Sony a7R II full frame mirrorless camera firmware update 3.30 in Aug 2016 has introduced a bug that “eats” stars in RAW and JPG astrophoto images when exposure time is 4 secs or longer, or BULB - these cameras are no longer suitable for astrophotography! However, a workaround is to use Continuous burst mode which unfortunately will reduce dynamic range as it uses 12bit not 14 bit sensor readout 1)
- Bad spatial filtering isn’t new to Sony’s Alpha cameras. Even with the older firmware, all recent Sony alpha mirrorless cameras including the a6000, a6300, a6500, a7S, a7R, a7, a7II, a7sii, a7rii exhibit the “Star Eater” issue when using the Bulb exposure mode - in these cameras, use timed exposures not BULB!
the hand held option
- the Olympus OM-D E-M1 mark II with a wide aperture ultra wide angle lens such as the unique Olympus mZD 8mm f/1.8 Pro fisheye lens at last allows very nice hand held exposures at 10secs!!!!
what you need
- high quality f/1.4, f/2 or f/2.8 wide angle lens that gives sharp star images across the frame wide open
- need f/2 or f/2.8 to avoid having to push ISO higher than 3200
- wide angle lens not only gives more of the Milky Way but allows longer exposures without star trailing becoming evident when using untracked cameras on a tripod
- even with a wide angle lens, many take vertical shots and stitch them as a panorama to capture the extent of the Milky Way
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- the Olympus mZD 8mm f/1.8 Pro fisheye lens is a very interesting lens to use to avoid need for stitching and given the 180deg field of view, but will cause considerable distortion
- if you don't like the fisheye effect, just de-fish it - see http://www.lonelyspeck.com/defish/
- the Samyang / Rokinon 12mm f/2.0 is a good affordable lens for mirrorless cameras but is MF
- Olympus mZD 25mm f/1.2 PRO lens is great for high resolution panoramic stitched images
- full frame cameras:
- note that most Canon and Nikon brand wide angle lenses are poorly corrected for coma and astigmatism, and thus many recommend:
- Sony FE 14mm f/1.8 GM the best ultra-wide for astroscapes
- Sigma 20mm f/1.4 DG DN Art 2022 model is designed for astroscapes with excellent edge-to-edge aberation control and sharpness and seems to be the best 20mm for this although it has more vignetting than the HSM dSLR version of this lens
- SonyFE20mm - sharper in the centre and much cheaper than the Sony 24mm but the f/1.8 is less light transmission and corners not quite as sharp and with slightly more astigmatism - need to stop down to f/2.2 to remove this
- Sigma 24mm f/1.4 DG DN Art 2022 model is designed for astroscapes with excellent edge-to-edge aberration control and sharpness and seems to be one of the best 24mm for this although it has more vignetting than the HSM dSLR version of this lens
- SonyFE24mm - optically the best lens even at f/1.4 but expensive and only 24mm field of view but the f/1.4 light transmission makes a big difference in videography of stars; For edge-to-edge star quality, best at f/4 if you have a tracker to allow longer exposures
- Sigma 14mm f/1.8 DG HSM Art full frame lens perhaps the 2nd best ultrawide, wide aperture lens for astroscapes and aurorae
- Samyang XP/Rokinon SP 14mm f2.4 - one of the best ultra-wide angle (under 24mm) lens on the market for shooting the night sky 2) 3)
- Rokinon/Samyamg 14mm f/2.8 best affordable ultra wide lens for astroscapes
- Zeiss Classic Distagon T 15mm f/2.8
- Rokinon 20mm f/1.8
- better star shapes than the Sigma 20mm f/1.4 DG HSM Art full frame lens
- Zeiss Batis 18mm f/2.8 for Sony E mount
- Sigma 20mm f/1.4 DG HSM Art full frame lens is acceptable and better than the Sigma 24mm f/1.4 DG HSM Art full frame lens (lots of vignetting and needs to be shot at f/2.8 to control aberrations) but not as good for stars as the Rokinon 24mm 6)
- Zeiss Milvus 21mm f/2.8
- Zeiss Batis 25mm f/2.0 for Sony E mount
- Zeiss Classic Distagon T 25mm f/2.0 - considerable vignetting and lower transmission
- Zeiss Classic Distagon T 28mm f/2.0 - needs to be stopped down to f/2.8
- Zeiss Otus 28mm f/1.4 - one of the best wide angles, almost no CA, very low coma, well controlled astigmatism but some is present, but it does cost $US4,990 and is MF
- Sony Planar T* FE 50mm f/1.4 ZA for Sony E mount
- Sony Zeiss 55mm f/1.8 for Sony E mount
- Tamron 15-30mm f/2.8 is better than the Nikon AF-S 14-24mm f/2.8G ED as it is sharper with less coma and costs around $500 less 7)
- Canon EF 16-35mm f/2.8L USM III is much better for astro work than its predecessors
- see also:
- tripod
- optionally with a panoramic head if doing stitched shots with foreground subjects in the image
- lens dew heater
- no point trying to shoot once dew falls on front of the lens!
- dew forms when lens becomes colder than the dew point
- exposure trigger
- if doing exposures longing than 30 secs for the landscape component, you will need either:
- shutter release mechanism to keep shutter depressed during BULB, or,
- use an Olympus OMD camera which has Olympus Live Time mode (just press shutter to start and again to end when it looks bright enough - or just use the TIME mode if you don't wish to see the image developing)
- can also use these cameras in Olympus Live Composite mode to do star trails without blowing out foreground subjects!
- these cameras also allow Live Boost mode so you can readily see and focus on the stars in the EVF if using wide aperture lenses
Nice pano stitch of 10 images at f/2.8, ISO 3200, 15sec, but the Tokina 11-16mm f/2.8 lens is showing awful image quality at the tops of each frame - lens choice is critical!
camera settings
- manual white balance:
- for Milky Way generally looks best at 3200-3900K to keep stars looking blue
- manual exposure for the Milky Way:
- many aim for an exposure value of -8EV for the Milky Way = 25sec, ISO 3200, f/2 to 2.8
- shutter speed:
- to avoid noticeable star trailing, exposure length should be kept below 400/(effective full frame focal length), however, even at this shutter speed, you will get star trails on large prints from high resolution digital sensors so you may prefer to use a shorter exposure by 5-10secs, or, as calculated by this complicated NPF rule formula 8):
- (35 x aperture + 30 x pixel pitch) ÷ focal length in mm = shutter speed in seconds
- aperture = f/ratio eg. 1.4
- Pixel pitch = the camera sensor’s physical width in millimeters ÷ number of pixels in width x 1000 to measure it in microns
- thus for:
- Olympus OM-D E-M1 mark II, use a Panasonic Leica DG 12mm f/1.4 Summilux ASPH lens to give 12mm f/1.4 at 12 sec (or Olympus mZD 8mm f/1.8 Pro fisheye lens at f/1.8 at 20sec), at ISO 3200 = exposure of -7.66EV which ranks the E-M1 II in the top 6 cameras for high quality Milky Way stars - unless Sigma's forthcoming 14mm f/1.4 full frame lens offers great star shapes.
- Sony a7 II full frame mirrorless camera, use a Samyang 24mm f/1.4, 10 sec exposure at ISO 3200 = exposure of -7.35EV (if using the Sony a7S full frame mirrorless camera, Sony a7R II full frame mirrorless camera or Nikon D5 pro dSLR then can use ISO 6400 for an even better exposure without significant drop in image quality from the high ISO
- preferably should look overly bright in camera (neutral or ETTR histogram) without blown highlights
- to get the whole view of the Milky Way, you will need about 14 vertical images stitched if using a 14mm lens (on a 35mm full frame camera)
- landscape exposures (moonless sky):
- 20min, ISO 1600 at f/2.8 (may need a warmer on the lens to prevent dew forming)
- 5min, ISO 1600 at f/2.8
- 1-10min, ISO 400-1600 at f/8 with light painting of foreground - may need multiple shots with different focus points
- RAW mode
- long exposure NR ON or AUTO
- turn image stabiliser OFF
post-processing
- *unless you make it absolutely clear to the audience, do NOT clone parts of the sky to make the image look better as this renders it a fake, deceptive image
- in Lightroom, remember to:
- set Sharpening Masking to a high value to avoid sharpening blank areas of the sky
- add some Clarity to make stars pop (but too much gives a halo artefact)
- apply some noise reduction
- may need to remove vignetting if planning to stitch images
- then in PS:
- you need to blend in all the images:
- Milky Way exposures
- foreground landscape exposures
- apply further noise reduction (can be done by 3rd party plugins such as Nik Dfine)