Here is an example of a simple 360 deg panorama in Hugin that shows that good results can be obtained using “wrong” techniques. Specifically, you can use autoexposure, even for highly contrasty scenes that normally would required bracketed exposures and HDR+Tonemapping.
For post-processing, you can crank up the highlight and shadow recovery and individually tweak each frame for exposure. It is not necessary to shoot with manual exposure with each frame with the same exposure settings, nor process them identically.
Additionally, you do not need very much overlap between frames in many cases, only a few control points can do, and they only need to be placed along the seam lines. A few manually well placed control points can quickly give a good stitch.
This example also shows some other things that you may need to watch out for. You should clean your lens and sensor. I’ve not been able to do much photography lately so my equipment has not been maintained as well as they should have been. My lens also needs to be adjusted as the plane of focus is slightly skewed and it does not reach infinity focus. This is slightly masked by the depth of field at f/8 but can still be detected in the full sized source imagery.
I have provided downsized source images and a Hugin project file if you want to have a look at how it was assembled. I only spent a few minutes putting it together so I’m sure it could be further optimised. The final full sized and processed panorama can be seen at 360Cities. I adjusted the exposure curve, sharpened the image, tweaked saturation, and repaired the dust spots in the sky.
I had the opportunity to visit London and managed to find some time to shoot some panoramas. The weather wasn’t ideal with scattered showers and cloudy skies but the rain managed to hold off for the time I had available. In the lead up to Christmas, festivities were in full swing so Christmas lights, trees, and markets would provide colourful subjects.
I use a Sony A7m3 “fullframe mirrorless” camera. Previously I used a Sony A5100 with an APS-C sized sensor. They both have 24 megapixels but the A7m3 has considerably better dynamic range and high ISO performance.
I use the Samyang 12mm/2.8 Fisheye lens. This is a “fullframe fisheye” lens, “fullframe” refers to the fact that the image circles covers the entire sensor. Previously I used the Samyang 8mm/2.8 Fisheye lens that is a “fullframe fisheye” on the A5100 APS-C camera. The 12mm/2.8 has better flare resistance that is noticeable on night scenes.
I use the Nodal Ninja 3 Mk III panohead with Rotator Mini and Nadir Adapter. I upgraded from the Nodal Ninja 3 Mk I/II hybrid that had served me well shooting the Konica-Minolta 7D, Sony A700, A580, A77, NEX-7, and A5100 with a Peleng 8mm, Sigma 10mm, Samyang 8mm/3.5, and Samyang 8mm/2.8 over the years. The new panohead fits my upgraded rig a bit better and the Nadir Adapter is a time saver. I use a Benro C-169M8 Travel Tripod with a Manfrotto 496 ballhead.
The raw files were imported in Capture One 20 Express (for Sony). I selected the frames that would be assembled. There were many spare frames since I would shoot extra shots to capture moving objects (people, cars etc,), high contrast scenes (usually base exposure and -2EV), and to fill in shadows.
The selected frames were then adjusted in a batch. First thing is to apply the same white balance setting. Shots taken at night under a variety of mixed lighting can be challenging to get the white balance “right”. Usually, I try to balance the colour temperatures throughout the scene, taking care with the green-magenta shifts that can occur with fluorescent and LED lights. Other common settings include chromatic aberration correction, black level point, sharpness fall-off, and clarity.
Each frame is then adjusted for exposure, It is critical to preserve the highlights, this is done by a combination of highlight recovery and overall exposure. Some shadow recovery can be used to prevent the darker areas being crushed to black but there is no need to fully recover shadows at this stage.
I usually leave the saturation and contrast untouched. These can be adjusted after stitching. Occasionally, I may need to reduce the contrast of the nadir shot so that it blends in with the edges of the other shots.
The adjusted raw files are now exported as 16-bit TIFFs in Adobe RGB colour profile. These are then imported into Hugin for assembly and stitching. There are other good programs for creating panoramas including PTGUI but Hugin has the advantage of being free. Hugin is also quite powerful, allowing detailed control of the alignment and exposure optimisation process. For a more automated solution, PTGUI is probably a better choice.
After the images have been imported into Hugin, the first step is to mask the images to remove the panoramic head and tripod that may intrude into the edges of the frame. The Zenith and Nadir are also cropped to circular regions. It is useful to define the focal length and projection type of the lens, 13.1mm and full-frame fisheye are used for the Samyang 12mm/2.8 Fisheye. I assign the same lens to the horizontal frames and separates ones to each of the Zenith and Nadir. The Nadir in particular will need to be optimised differently to the other frames in order to compensate for the likely shift in position.
Next step is to add control points (CPs) between overlapping frames. There are automatic methods but I prefer to manually add points. I find that I spend more time fixing automatically generated CPs than if I had added them manually. I start off by connecting the horizontal frames. To get a good stitch, all that is needed is that the frames match along a seam line, generally placed along the middle of the overlap region. Hence, I only add CPs along a line that stretches from the top to the bottom of the overlap. For the Nadir, I add 2 to 3 CPs per overlap with the horizontal frames. Extreme distortion parameters will usually need to be used to get it to match up with the rest of the pano.
After the CPs have been added, then the position optimisation process than begin. I start with optimising just the position. Next I optimise position, angle of view, and barrel. Finally, I optimise all parameters except translation. Throughout, I check for any CPs that have large errors as this might indicate that they may be incorrectly placed. I either correct the placement or delete them if there are sufficiently many other CPs.
Hopefully, after several rounds of optimisation and tweaking of the CPs, the errors will be small (maximum of a few pixels in a 14Kx7K pano) and visually the pano looks aligned with no obvious errors in the preview window. Additional masks may be added to remove moving objects or else control what elements from each frame end contribute to the final pano.
The next stage is photometric optimisation. For many years now, panoramic software have been able to cope with source photos shot at difference exposure values and stitch them together in a seamless manner. This allows a more flexible and arguably optimum manner to capture the initial source photos . I will use autoexposure to create a base layer together with bracketing of selected frames to capture blown highlights. In the exposure optimisation stage, Hugin can exposure match all the frames in a near seamless way. I can then export the full pano at various brightnesses which have shadow, mid, and highlight detail separately. These are then combined using Enfuse to produce a single pano that incorporates the detail in both shadows and highlights in a process called exposure fusion.
The exported pano (exposure fused if necessary) from Hugin in equirectangular formal is then post-processed. I use Picture Windows Pro 7 as my main image editor , with Photoshop 6 for cases where I need to do spot removal or extensive cloning. First step is to adjust the contrast using curves. I’ll first bring up the shadows as these will be a bit dark as I try to protect the highlights in the previous steps. Then I’ll apply an S-curve to boost mid-range contrast and compress the highlights. The preserved highlights can look unnaturally dark so I’ll bring them up near the top of the histogram without blowing them out.
Sharpening of the image is very important. I’ll perform a large radius unsharp mask, coarse sharpen, and a fine sharpen. The sharpening process utilises pixels in a region hence problems can occur at the +/-180 degree boundary of the equirectangular image. To avoid a visible seam arising from such non-global adjustments, I’ll create a pano 720 degrees (or 1080 degrees) wide before apply the filters. Then I’ll crop out a central 360 degree section to get back to a regular equirectangular projection.
Final colour adjustment is applied, both selective and global saturation. Any touch up (spots, shadows, or minor stitching errors) are then performed in Photoshop. I produce both a final TIFF and a JPG that is in sRGB for export to the web.
 Instead of using the same exposure value for all source frames, you can expose each shot optimally. For example, a scene may have 20 stops of contrast between one direction and the opposite, e.g. sun and shadow. The traditional method would be to use manual exposure and bracket, e.g. -6, -3, 0, +3, +6EV and use the camera DR to capture the ends of the contrast range. The +6EV shot would cover the shadow and the +6EV shot would cover the highlight. But this method is wasteful since usually the contrast in a single shot is less than the full bracket range. Often only a single shot in that direction is required, or else a second bracketed shot will cover the remaining fraction of high contrast cases. Instead of 30 shots (4+1+1 shoot pattern times 5 bracketed shots), it is usually possible to only use 7 or 8 shots in total. The final result is as good as the fully bracketed version but with a considerable reduction in shooting time, this can be significant in low light conditions but can also be a major factor in situations where there are moving objects and/or changing lighting conditions.
 Picture Windows Pro 7 is now free. A newer version has been developed by version 7 is still a very useful image editing program. The paradigm is different to that of Photoshop so at first glance it may look to be fairly crude. But it is small, quick, and easy to use for many routine image adjustment tasks.
 I have no commercial relationship with any companies or their products mentioned in this post, other than being a satisfied customer of some of them.
The recent viral photo of a dress of controversial colour demonstrates that the perception of colour is a complex psychovisual phenomenon that involves not just the physical electrical impulses produced by the light receptors in the retina but also interpretation by the brain based on context and expectation. It also underscores the importance of getting your exposure and whitebalance correct.
Philosophers have used colour in debates about the notion of “qualia“, or the “the ways things seem to us“. From a photographic perspective, we can understand how a dress which under normal lighting looks to be royal blue with black lace can look in the photo to many people as being white with gold lace. There are two issues with the disputed photo that contribute to the confusion, it is badly exposed and the auto white balance is extreme.
I assume that the photo was taken by a phone and that the autoexposure was fooled by the darkness of the dress. The photo was consequently overexposed leading the royal blue parts of the dress being rendered a much lighter shade of blue. The dark lace parts of the dress are also brightened and now longer looks black.
The second issue is that the camera then tries to colour correct the image by setting a white balance. It misinterprets the scene as being taken under high colour temperatures, e.g. at dusk with the illumination of a clear blue sky. To compensate, it changes the colours in the scene, effectively trying to make the blue dress look more white as it assumes that this is “actual” colour of the dress. To bring blue closer to white, the camera adds yellow to the scene (you can tell from the yellow colour cast to the background). The dark lace of the dress, already made a lighter shade by the overexposure, is now given this yellow colour cast which can be interpreted as being a golden colour, especially in the context of the rest of the dress which is rendered as palish blue.
These two effects combine with the way the brain tries to work out what the colour of objects are from visual stimuli. Since our vision has to operate under many different types of lighting, what we perceive as colour of an object is not actually the actual colour cone responses, but what our brain retrodicts based on our assumptions about the lighting. An apple under noon day lighting will look different compared with viewing at dusk, but we don’t usually say that the apple has changed colour because our brain will take the different lighting conditions into account and interpret that the apple is the same colour. The case of the dress is simply a case of the camera being fooled together with the way our vision system operates.
Previously, I discussed selecting a tripod and head. A tripod opens up a whole new vista of photographic possibilities but to make the most of the stability of a tripod, proper technique is needed.
Stability and Mounting
The first consideration is making sure you’re not overloading your tripod legs and head. The heavier your equipment and the narrower the angle of view (more zoom), the more sensitive will the final picture be to residual vibrations and external forces such as wind. I seldom shoot at focal lengths greater than 200mm so my tripod needs are comparatively simple. If you have 300mm or longer zooms, a large sturdy tripod with a gimbal mount is recommended.
If your tripod does not have a quick release, you’ll be screwing your camera directly onto the mounting plate of the tripod head. One thing to watch out for is that if you take a photo in portrait format, the camera can twist and unscrew itself. You may find this happening if you tilt the camera to the left (so that the handgrip is to the top). By rotating the camera so that the handgrip is to the bottom, then the torque of a heavy lens will tighten the mounting screw instead and preventing further rotation.
If you find yourself having to mount and dismount your camera from the tripod repeatedly, a quick release plate might be a good investment. It’s increasing rare to find tripod heads without them in any case. The de facto standard mounting solution is the Arca-Swiss plate which has a dovetail and a matching clamp. Do note that some variation exists between nominally compatible plates and mounts from different manufacturers. There are many other types of quick-release mechanisms to suit cameras of different sizes and applications.
You should avoid raising the centre column of the tripod if possible as this makes the whole system more flexible. For the same reasons, you should spread the tripod legs out to give a wide base.
The main priority of using a tripod is stability, whether for long exposures, or simply to get rid of hand shake. To reduce the possibility of introducing vibration when activating the camera, you can use a remote shutter release. The traditional mechanical remote release is a plunger attached to a sheath and cable screwed into the shutter. This was superseded by electronic wired remotes which allowed functions such as an intervalometer and times long exposures (minutes to hours). Wireless remotes (usually IR) are becoming popular nowadays. Any of these will prevent extraneous vibration due to touching the camera when starting the exposure.
If you find yourself without a remote release, your camera may have a shutter delay function, usually 2 or 10 seconds. The 10 second delay is to allow you to get into the shot, the 2 second delay is so that after pressing the shutter release, the camera and tripod has time to settle before the actual exposure. If you do not need to trigger the shutter at an exact time, then a 2 second delay can often work as well as a remote release.
Even if you use a remote release or camera timer, there are other sources of vibration that could impact upon sharpness. In an SLR, the mirror has to be raised out of the beam path before the shutter activates. This raising of the mirror can lead to vibrations. Some DLRs have a mirror-lockup function that allows the vibrations due to the mirror being raised to dampen. It is often combined with the 2s timer delay. “Mirror-slap” will usually have greatest effect at an low to intermediate shutter speed, a critical range of exposures where mirror-lockup gives greatest benefit.
Even on non-SLR cameras, the shutter actuation can cause vibration. The opening of the front-curtain can cause blur. Some cameras have “electronic first curtain” (EFC) where the physical first shutter curtain is replaced by an electronic means of starting the exposure. This eliminates any vibration at the start of the exposure.
Sometimes the ground itself can vibrate, e.g. bridges. In this situation, it will be difficult to achieve sharp results during long exposures. You may want to time your exposures in between passing cars or pedestrians. On some surfaces, the distortion caused by your own shifting weight can cause the tripod to move during long exposures.
One thing to watch out for is image stabilization, either lens or camera based. Some image stabilization systems do have modes specifically for tripod use but often you’ll get better results if stabilization is switched off when mounted on a tripod.
In my last post, I spoke of the importance of getting a good tripod. Many people skimp on their tripod and consequently do not get the best use out of them. Most importantly, a light and compact tripod will be more likely to be on hand when you need it. It’s a case of any tripod is better than none.
I mentioned another oft neglected item and that was the tripod head. It connects the camera to the legs and should be sufficiently adjustable yet still rigid. One thing to remember is that the load ratings of heads are to be taken with a very large grain of salt. There is no standardised way of specifying the acceptable load that a head can handle. It is actually the torque that a camera+lens exerts on a head that most needs to be resisted.
There are two main types of head, pan and tilt heads (panheads) and ballheads. Panheads have two or three separate axes of adjustment, pan, tilt, and roll (video panheads will omit the last). There will usually be three different knobs or handles, one to control each movement. Sophisticated versions will have geared mechanisms allowing fine adjustment of each axis. In contrast, a ballhead will use a single locking mechanism to control the motion of a ball and socket joint allowing all three axes to be adjusted simultaneously. A separate pan movement is also usually added to the base of the ballhead. The advantages of a ballhead is that it is often much quicker to adjust. They are often smaller than a comparably rated panhead.
For panoramic use, the footprint of the head becomes crucial. Looking down from the viewpoint of the camera rotating around the no-parallax-point, often you’ll have the baseplate and various knobs taking up valuable area in the nadir region. It can be tricky to find the right ballhead which minimizes the nadir hole. My current favourites are the Novoflex Ball 30, FLM CB-24, and Manfrotto 494 (with the friction knob removed). The 494 allows the locking knob to be adjusted so that it can point down in the locked position, useful for reducing the nadir footprint. The same can be achieved on the Ball 30 by unscrewing the knob and reattaching it in the right position.
To reduce my equipment load, I have dispensed with quick release (QR) plates. These simply add bulk, especially if I need to attach the camera to both the panohead or the tripod ballhead so requiring extra plates and locking mechanisms. I find it takes little time to screw on the camera or panohead. Unfortunately, it is increasingly difficult to find higher end heads without a quick release system. It may be a fashion trend since having Arca-Swiss plates on everything looks “more professional”.
A good ballhead will be secure when locked down. It should be rigid so that vibration is minimised. For large and heavy lenses, these should be mounted to the head rather than the camera. For the extreme telephoto lenses, a gimbal mount may be warranted. These place the rotation point near the centre of gravity of the camera lens, reducing the torque and giving a more stable platform.
Note that there are two commonly used screw sizes used to attach tripods, heads, and cameras. These are 1/4″ and 3/8″ screw sizes. Most camera tripod sockets will be 1/4″, but tripod screws can be either. You can get adapters between the two screw sizes, it is usually not a problem to adapt a 1/4″ male screw to a 3/8″ female socket, but the reverse adapter is quite bulky.
They are the most under-appreciated component of your kit. You may pay hundreds or thousands of pounds to get the latest high resolution camera or lens, but the simplest and most cost-effective way of obtaining the sharpest photos is to get a good tripod and use it.
First of all, bring a tripod with you if you can. Obviously, a tripod is useless for street photography but for many other activities, a tripod becomes practical. For some types of shot, such as night photography (left), it is essential.
Get the best you can afford. There is no perfect tripod, but there are plenty of terrible ones. A tripod needs to be sufficient for the equipment you are going to mount upon it. It also needs to be light and compact enough so that you will take it with you. Unfortunately, this usually means that the third variable, cost, is the one to suffer. But the old adage, “buy cheap, buy twice”, applies especially to tripods.
Depending on what you shoot, you may require several tripods. I have a large sturdy tripod which never leaves the building where my office is. I use it for product shots, groups, and self-portraits. For general travel, I have a Benro C-169M8 Travel Angel carbon fibre tripod similar to this. It is for me the right balance of compactness (39cm folded), lightness (1.3kg), and sturdiness (8kg max. load) for doing panoramas and long-exposure photography. If I need an even more compact tripod, I have a Sirui T-1205x tripod which shaves a few hundred grams and a few centimetres in length. I also bought a Benro Traveller Flat C1190T as I was intrigued by the way it folded flat. It occasionally gets used when I have to pack it in a tight space where a conventional tripod would be too thick.
I still have and use a Gitzo G1028MkII Mountaineer tripod which I bought about a decade ago. Compared to more recent tripods, it’s still very light and packs down with the centre column reversed (without having to bend the legs 180 degrees). The rotating leg locks are a bit fiddly and it’s not quite as sturdy as the Benro and Sirui tripods but with care it can still provide sharp panos. If I had the budget, I’d look at getting a GK1580TQR5.
If carbon fibre is beyond your budget, another option for a compact but still acceptably sturdy tripod is Velbon. Their Ultra Luxi or Rexi range pack down quite nicely and have a quick leg un/locking mechanism. The Luxi comes in L and M sizes, I found the M to be reasonably high. The Ultra Maxi tripods unfortunately do not allow you to swap the head restricting you to the included panhead. The Rexi comes without a head, whilst the Luxi panhead can be replaced, something I advise if you want a more compact setup, the standard one is quite large and heavy.
My tripod selection is skewed towards wide angle and shot teleprime lens use. If you use longer, heavier lenses, then you may need to look at large and heavier tripods to get the required stability. One has to also remember an equally important part of your tripod and that is the head. I’ll address that in a later post. I shall also cover tripod technique.
If you’re serious about photography and your friends and family consider you handy with a camera, at some point you’ll be asked, “Can you shoot our wedding?” Here’s my point of view, having been in this situation as a relative/friend with a camera way too often.
First point of advice: Run away! You get the occasional cowboy but your working professional wedding photographer actually earns their keep and I have the utmost respect for what they do day-in, day-out. It’s not just about having expensive cameras, even more expensive lenses, or fancy software, what you should be getting when hiring a pro is years of experience handling a high pressure situation and getting the shots when it matters. You don’t get many second chances at weddings and considering how important the photos are to how it will be remembered, the couple should think carefully of not ascribing the appropriate budget to photography, especially considering the total cost of the wedding.
If possible, convince them to hire a professional photographer, one with experience and with a good track record, especially in being able to produce photos in the style preferred by the bride and groom. Just as a marriage requires matching the right people, it is important to get a photographer who will be appropriate for the occasion. The primary photographer should be responsible for the “money shots”, the ones which are the bread and butter of any photo album. Have the couple draw up a list of shots which they would like, especially the group photos which can be endless in their permutational possibilities. Having a trusted friend of the couple (usually the Best Man) handle the logistics of the group shots is one way of reducing your workload to simply taking care of the photos instead of herd management. The last thing you want to have to worry about is where is Aunt Murtle or nephew Johnny? It’s easier if there is someone familiar with friends and family who can go chasing up on errant guests.
Try to enjoy yourself and let the primary shooter get the primary shots, you do what you can to fill in the gaps. If I can get out of being the primary photog for friends, I usually end up doing street photo/candid shots to give a more informal behind the scenes sort of document to the day. When you don’t have the pressure of being first shooter, you can try for the more artistic or risky shots, most of them will fail but you could end up capturing their favourite shot of the day. This may require getting in close to the other guests, or hang back and observing. It depends on the situation and you have to be adaptable. I find that a wide angle lens and being in the thick of the action is a good way of getting fun and intimate shots.
Even as second shooter, I usually have two bodies to reduce lens swapping. One with a 70-200mm telephoto zoom, the other with a 16-50mm standard zoom. I’ll also have a 35mm/1.8 and 50mm/1.4 large aperture primes for low light situations. It is important to anticipate what camera/lens is required at any given moment and to have it ready. For the official ceremony, you should have a good idea of the sequence of events and what shots are needed. Rehearse following the bride down the aisle and the route when leaving the ceremony. Scout the areas where you will do the formal portraits and groups shots. During the more relaxed and informal moments, you have to keep a good lookout for photo opportunities. Kids are invariably cute, especially all dressed up for the occasion.
Preparation will make things run a lot smoother. Planning the day, where you have to be and when, what equipment is needed for which shots, and even the little things like where to park and how to get all your stuff safely to where it needs to be. A checklist can help prevent you forgetting vital tasks.
It is tempting to use your camera as a machine gun, shooting anything that moves. Afterwards you’ll regret having to go through thousands of images. Certainly take those extra safety shots for the ones which matter (groups shots, formals, portraits), but you should try to be selective about the other shots, making sure that each frame counts. It’ll reduce the amount of backing up, editing, and processing you’ll need to do. There’s no harm in keeping shots varied, just don’t get too focussed on repeated shots of the same subject.
Post wedding, you will need to sort, edit and produce a contact sheet for the couple to have a look at. Even at this stage, you should be ruthless in pruning extraneous shots. Couples always have a tendency of wanting even more shots, magnifying your workload. Particularly if you are doing a wedding as a favour or for reduced rates, you want to restrict the amount of unnecessary effort you have to expend. You need to be strict in the number of agreed final photos to deliver. The final output will determine the degree of post-processing required. A set of 6″x4″ prints to put into an album will require only cursory white-balance, levels and curves. Large portrait prints may require a visit to Photoshop to get rid of blemishes, sweat stains (not a task I relish, especially having to manually touch up a hundred or so photos), to smooth skin, and generally make each shot look its best.
I just received my copy of the Samyang 8mm/2.8 fisheye in native NEX mount. I’ve tried it on the NEX-7 and have some very preliminary remarks. First the good news, it’s sharp, light, compact, pretty well made, and matches the form factor of the NEX-7 quite well. The only downside so far is the interaction of the lens with the sensor leading to magenta corners.
This lens colour cast is due to the way that off axis light rays interact with the filter stack on top of the sensor and the pixels themselves. The different coloured sites in the Bayer array are affected differently leading to colour casts. This can be a problem with certain lens designs where the exit pupil is situated close to the sensor (non-telecentricity).
To fix this, you can use CornerFix, a program which takes DNG files and applies a rescaling to the data to compensate for the lens colour cast. One has to first create a reference file from which the compensation can be calculated, not exactly straight forward for a 180 degree diagonal fisheye. I have made such a correction profile and people can download the file (you may need to right mouse click and choose “save link as”, or similar). The lens was set at f/5.6 but the profile should work more or less at other apertures. The correction isn’t perfect, but for most photographic scenery it corrects the majority of the colour cast, as well as the vignetting (which can be adjusted).
Thanks to all who attended the Edinburgh Photoworld. I hope that people were able to get something out of my talk. I took a pano at the start of the day (left). The full pano can be seen here. More of my panoramas can be found here.
I have had requests for the links I gave at the end of my talk. Here are some links below, it’s by no means exhaustive, but hopefully they will be able to get you started.