Introduction to 360° Nighttime Panoramic Photography

Photo linking to a 360° PanoramaAbove: the night sky as seen from our driveway. It was because of this view that I acquired my first telescope and joined the Saint John Astronomy Club to find out more. Taken between Norton and Cassidy Lake, New Brunswick in November 2017. Click the pic, use your mouse to look around.

Overview~

Photo showing the various positions of a dslr on a 360 pano head.

Making 360° panoramas of the night sky is relatively easy, but it does require some specialized equipment and software. It does not require a huge investment, especially if you already own a DSLR, have a computer, and have some working knowledge of photo processing programs such as Photoshop, Lightroom, etc.

However, before approaching the concept of making 360 panos, two terms must be acknowledged because they affect the Why of everything: What is Parallax and What is the Entrance Pupil of a Lens?

Parallax and Entrance Pupils~

Photo describing terms to consider before making 360 panos--What is Parallax, and What is the Entrance Pupil of a lens.[click to enlarge]

Without getting too long into definitions you can Google yourself, Parallax is a point of view shift seen by lenses and our own eyes. You can see it for yourself by holding your finger or thumb out in front of you, shutting one eye and then the other and watching something in the distance “flip” back and forth. And that’s with your eyes relatively close together in your head! Even if you stand in a large room, looking across the room past a cross pane in a window, you can make an object half a mile away flip on either side of the cross pane.

This “parallax effect” can play havoc when trying to stitch together photographs. If you’ve ever used Photoshop>File>Automate>Photomerge, you may have had some hit or miss results. Perhaps you’ve been at a wedding and wanted to photograph the head table but couldn’t get back far enough, or been at a scenic lookout too vast to take with any lens, so you take a series of pictures in a row and try to “stitch” them later, only to find that weird results sometimes happen.

Part of the reason for the problem in stitching is that the lens on your camera is moving across an arc as you are taking pictures. Lenses, like our eyes, have pupils where the light is gathered. This is called the Entrance Pupil of a lens. Just like our eyes with the pupil and iris, it is set back in a bit. The Entrance Pupil of a lens is where the camera actually “takes” the picture. So if you can make an image “flip” back and forth with your own eyes close together, imagine what is happening inside a camera as it moves in an arc.

If only there was a way to keep the Entrance Pupil of the lens in the same spot as you move your camera. Well, there is. It’s called a 360 pano head.

Equipment & Software Requirements for 360 Panos~

Equipment and software needed for producing 360° night sky panoramic photography

1) A DSLR capable of Manual Mode~
Why manual mode? Because you are effectively creating one spherical photograph, one you can stand inside, which is made up of “panels” of the images you take. All exposures must be the same. Manual shutter speed and aperture, manually set ISO and White Balance, and any auto settings have to be disabled. That means Auto White Balance and Auto ISO have to be switched to Off.

2) A 360° Panoramic Head, either store bought or homemade~

Photos showing examples for some 360° Pano heads for a DSLR[click to enlarge]
There has been an explosion of pano heads, related equipment and software since I first delved into this about five years ago. At the time, I was only interested in doing daytime panos and it never even occurred to me to try night sky imaging. If you do go looking for pano heads my only suggestion is:
~Get one with click stops (most of them do now–handy in total darkness)
~Make sure whatever model you choose can support the weight of your camera and lens.
~Make sure that it allows for taking the Zenith overhead shot. Gotta get that Milky Way! Some pano heads are for “single row” panos as in real estate tours, etc., for taking 120°, 180°.
~Do check out the link Panoramic Photo Guide/Purchasing Advice or similar pages.

3) A wide angle lens, preferably a fisheye~
Why fisheye? Because the less shots you can take the better, and fisheye lenses lend themselves to spherical photography. In theory you could use any lens, but since the images must overlap a minimum of 20%, that could mean a lot of images taken in a straight 0° row, at 30 or 45° up, 30 or 45° down, plus the Zenith and Nadir (down) shots.

4) A sturdy tripod, the best you can acquire~
A ball head is helpful for leveling.

5) A remote shutter release for obvious reasons~

6) Processing software such as Photoshop, Lightroom, Gimp, etc.~
Whatever your favourite, the important thing is that all processing must be the same. So if you adjust Levels for example in a jpeg image to bring out the Milky Way, those exact same settings must be applied to all the other images. Creating presets and using them saves time and ensures accuracy. Manual exposures, identical image processing is key.

7) 360 stitching software~
PtGui, Autopano, Panoweaver, Pano2VR, shareware Huggin, etc.

A screenshot of the Control Point window in the stitching software PtGuiStitching software is designed to find commonalities, or control points, between images that allow it to “stitch” the photos together. In the PtGui Control Points window of the daytime pano shown above, the software found 57 control points automatically between images 3 and 4. In the nighttime pano shown below, it found only 15 because of darkness. [click any image to enlarge]A screenshot of the Control Point window in the stitching software PtGui--nighttime shot.

A screenshot of the Control Point window in the stitching software PtGui showing the preview slider.The photo above shows the Preview Exposure slider which we can use to “see” more possibilities if we need to find more control points in a dark sky image. In PtGui, the Preview Exposure slider is your friend, especially when trying to complete the stitch with the overhead Zenith shot. You need at least 4 common control points between images for a successful stitch in PtGui. Preview does not affect the appearance of the actual image.
Note: it may not be possible to find 4 control points between the Zenith image and all of the horizontal shots, but 2 images out of 6 will generally work for a successful stitch.

Some examples are shown below. Click the pic, use your mouse.

A Visit to a Star Party~

Link to a 360° Panorama of the Livingston Lake Star Party in twilight of August 2017

Livingston Lake, New Brunswick~

Link to a 360° pano of Livingston Lake at 1am, New Brunswick, next to Fundy National Park

National Star Party at Irving Nature Park~

A 360 pano of the National Star Party at Irving Nature Park celebrating Canada's Sesquicentennial in July of 2017.This was at the National Star Party event at Irving Nature Park in Saint John, NB, in July of 2017. Most of the crowd had left by this point. It was a beautiful evening.

Astronomy by the Bay~

A 360° Panorama on a June evening at Saints Rest Beach in Saint John with Astronomy by the BayA typical June evening at Saints Rest Beach in Saint John with fellow astronomers and members of the public with Astronomy by the Bay.

What I Use~

For what it’s worth, the equipment I use is fairly old– a Nikon d5100 DSLR, a used 10.5mm Nikon Fisheye, an old Panosaurus 360 head I bought for $99 USD–now discontinued. I shoot RAW and process in Adobe Camera Raw or Lightroom and then Photoshop, then stitch in PtGui. PtGui is a learning curve but very intuitive. With my setup I need 6 shots all way around @ 60° plus a Zenith shot, the Nadir shot I usually don’t bother with at night. The first night sky pano I attempted was in my backyard shooting jpeg ISO 640 @ 30 sec and everything turned out fine. I now shoot RAW 1600 ISO @ 30 sec to try to get that extra something out of the incredible night sky we have here in New Brunswick.

360° Panoramic Heads~

Nodal Ninja
iOptron iPano Robotic Head [mainly for gigipan photography]
Manfrotto Pano Heads
Easy Pano Pano Heads
Mengs Photo Panoramic Head [China, sold by Gumptrade or ebay]
360 Precision Atome Pano Heads [British, lens specific collar]
FLMCanada Pano Heads [links to purchasing not all working?]
Agnos Pano Heads [Italy}
Acratech Pano Heads [collar for a Sigma 8mm fisheye only]
Panocatcher Robotic Panorama Heads[European]
Bushman Panoramic Heads [European]
Cambo Panoramic Heads [European}
Novoflex Pano Heads [European]
Panosaurus [now discontinued, this is what I started with]
VR Wave Panoramic Head Database
Zen Photo [eclectic mix of photo equipment]
Really Right Stuff [wide range of photo & pano accessories]
Seitz Roundshot [handy if you have $12,000 laying around]

Note: The quality of some of the European panos is astounding, so even if you don’t want to order from there, it is interesting to check out some of the equipment (and see if they are being offered here).
This is a very fluid market right now. Websites and distributors are changing.

Good Equipment Reviews & General Information~

Panoramic Photo Guide/software and equipment reviews
Panoramic Photo Guide/Purchasing Advice
IVRPA Resources [wealth of information]
Canadian Nature Photographer/Spherical Photography
VR Wave

360° Stitching Software~

PtGui
Autopano by Kolor
Panoweaver by Easypano
Pano2VR by Garden Gnome
Hugin from sourceforge.net freeware/shareware
Microsoft ICE Image Composition Editor

Good tutorials~

PtGui Video Tutorials
Pano-guru Tutorials
Pano Guru Youtube Link
Panoweaver Tutorials
Kolor Tutorials
John Houghton Panos Tutorial, etc. [wealth of information]
360cities-How to get started
Wiki Panotools/tutorials [source of good general information]
Really Right Stuff [mainly for single row panos, lots of good info]

Entrance Pupil Database of Various Lenses~

Wiki Panotools/Entrance Pupil Database

How Many Shots do I Need with Various Lenses~

Wiki Panotools/number of pics for a 360
VR Wave-Panoramic Lens Database [Canon, Nikon, Sigma, etc.]
Panoramic Photo Guide/how many shots for panorama

Finding the No Parallax Point (NPP) of a Lens~

John Houghton Panos/find the NPP
Pano Guru Finding the NPP (Youtube)
Rosaurophotography Finding the No Parallax Point–Grid Method

More Resources~

IVRPA International Virtual Realty Photography Association
Wiki Pano Photographs & Resources
IVRPA Resources
360° Panoramic Photographers on Facebook


About this Page~

This page is just a collection of bookmarks and other information I’ve turned up over the years. Maybe it will save you some digging.

I would like to thank Paul Owen for his guidance on photographing the night sky.

Besides equipment one might purchase, there is no substitute for:
The patience of trial and error.
The willingness to make mistakes.

Questions? Please contact me via email or use the Comment section at the bottom of this page.

Cheers,

Jim Stewart

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Bringing Astronomy to Southern New Brunswick, Canada