As explained in the previous article, the main topic in photography is how to get enough light on your sensor. Specially in Underwater photography, Aperture is a huge topic, that’s why I discussed it first. As explained, Aperture determines how wide my lens opens to let in light. There is another factor that comes on top of that however: For how long do I let light into the camera?
Shutter speed determines how long I let light into the camera and therefore on the sensor. The longer the shutter is open, the more light can come on the sensor. So generally, specially in dark environments where light is sparse, you want to keep the shutter open as long as possible. The issue however is that the sensor records all the movement during that time as well. If there is too much movement, the image will look blurry. With a faster shutter speed, the image will be always sharper (provided the focus is given) even if the object of the camera is moving. So you have the dilemma between more light or more sharpness. Shutter speed is measured in fractions of a second such a 1/50 or 1/250. 1/50 is slower than 1/250 and lets in less light but will guarantee a sharper photo.
What determines my shutter speed requirements?
- How fast does your object move relatively to the frame of the photo?
Apart from the actual speed of the object you are taking, the size of the object within the picture is very relevant. If you are shooting with a wide angle at a coral garden and a small fish in a corner moves a centimeter during the shutter being open, you might not see any effect in the image. If you zoom in on the fish and it moves across the whole picture, it will be surely blurry.
- How much does the camera move during the shot?
You move the camera involuntarily when you push the shutter button. This effect is even more visible when you have a stronger zoom. On dry land, the general rule of shutter speed to avoid that from becoming visible in the image is to adjust the shutter speed at minimum to the zoom factor. So for example, when you shoot with a 50mm lens, use at least 1/50 of a second. If you have a 300mm lens, use a 1/300 of a second and so on. That, however applies only for dry land and stationary subjects. Under water, where you are moving, the subject is moving, you have to use faster settings than on dry land.
- Do I have a stabilized lens or camera?
There are more and more cameras and lenses on the market that offer image stabilization. If you have one of those, you might be able to reduce the shutter speed since it will reduce the hand shake but it will not compensate for the speed of the object you are shooting.
- Are you using a flash?
If you are using a flash, there is something called the flash sync speed. This is the shutter speed at which the camera can still communicate with the flash to set the right lighting strength. This needs to be checked in the manual of your camera. If you are using a flash, that sync speed will be your maximum speed. If you set it to something faster, you won’t get the right flash strength.
So what shutter speed should I set?
You need to find that out yourself. Take photos at different speeds and see if it looks sharp or not, right there and then. A safe range would be anywhere between 1/160 to 1/250, depending on your light situation.
ISO is a measurement of the light-sensitivity of your sensor. A high ISO will record more light, a low ISO will record less. The issue with using a high ISO is that the image is overall grainier and has sort of a colored grain, specially in dark areas of the image. More expensive cameras usually have a higher maximum ISO and will give you a better picture quality despite a high ISO.
If you shoot without a flash, I would leave that setting on automatic. By changing the aperture and the shutter speed you already have enough tools to handle yourself. Let that one be controlled by the camera. There is a risk of course that the image will be grainy, but better than than blurry.
If you are shooting with a flash you can set that to a fixed, low value to get the maximum image quality necessary.
Why is UW photography different from “Dry” photos?
Well, in most parts it’s the same. Dry photos are more complicated from the point of view that your possible range of settings (for example shutter speed) is much wider. Due to the fact that you can easily use a tripod and shoot an apple on a table allows you to take exposures for much longer than it would ever make sense under water where almost everything is moving. On the other hand, UW is more challenging because you need a flash in most cases and the darkness and movement is putting increased technical requirements on the equipment. On top of that, wildlife photos are challenging for the photographer since the wild life is, well, wild, and does not normally just wait around for you to take a picture. So the speed at which you will need to be able to change the settings on your camera to take a good photo is completely different. Imagine taking a photo of a 2cm small slow-moving nudibranch with your strobes and then you see a shark swimming by that is too far for your flash to reach. You will need to switch of your flash and adjust all the other settings accordingly within a few seconds. So it’s challenging for your equipment as well as for you.
Knowledge is key
The ultimate goal of becoming a better photographer is of course the better picture, but the only path to that better picture is to be able to reliably produce them instead of just having lucky strikes. Luckily, photography is not some kind of black magic. Once someone understands the base principles, it’s much easier to look at a photo and realize what went wrong, change some setting and try again. As long as you need to guess and possibly change several settings every time without knowing what you are doing, you won’t learn anything and just be frustrated with the outcome.
Of course, underwater is not the same as being in a studio. You won’t have endless time to setup your shot when that whale shark swims by you. But then again, the better you know what to do in such a moment instead of guessing will dramatically improve the outcome.
In this article, I will link the most important technical terms to their Wikipedia article in case you want to read more about the technical details.
The basic principle
Light (from whatever source) hits an object (a fish) and gets reflected towards the camera. It enters the lens, the camera opens the shutter and lets image on the sensor. The shutter is closed, the image is recorded. So in essence, it’s a matter of light reaching the sensor. The major questions are:
- How much light is there? Where does it come from?
- How much light do we let on the sensor?
- How do we position the camera?
How does light work?
While I won’t get into the actual physics of light, there are some ways to visualize to help you understand the principles.
- Imagine light as a stream of water:
This is helpful for lenses. There are bigger diameter lenses and smaller ones. Further, lenses have an aperture that can be closed and opened to control the amount of light coming in, like a larger or smaller water hose. The bigger the lens, the more maximum light can “flow” in. A cellphone has a lens opening of maybe 2-3mm. A full-frame lens for a DSLR can have more than 2cm. If there is not enough light coming in through the lens, it will never reach your sensor – no matter how many megapixel it has.
- Imagine light as a handful of sand:
This is helpful with image sensors. If you have a 10MP (Megapixel) sensor, i.e. 10 million pixels on your sensor, but you let in only 5millon grains of sand, half of your sensor does not get any light. Or in other words, if you have a camera with a bigger sensor, you also needs more light or a bigger lens to get the same mount of light per pixel of your sensor. Some modern cameras will switch combine sensor pixels for low light photography to compensate for this issue. This halves the resolution however.
Controlling the light: Aperture
There are various ways to control the light and each of them influence the image in a different way. Let’s assume – to keep it simpler for the start – that we do not have a flash. So let’s start as the light moves, with the lens first. As described above, we can imagine the light flowing onto the lens like a stream of water. The bigger the opening, the more light can come in while the shutter is open. This is controlled by the aperture. Larger lenses have a wider maximum aperture.
However, using a wider aperture also changes the way your image looks. Look at this graphic:
On the top, there is an example of a wide aperture, on the bottom a narrow one. The light reaches the camera from the object we want to take a photo of (the green lines). The sharpest focus will be at the intersection of the green lines and up to a certain distance of the lines, the image will be still reasonably sharp for our eyes. In both aperture examples, I marked an area of the same height (i.e. the same sharpness) with a blue box.
As you can see, the wider aperture has a much narrower area where the image will be sharp. This is called Depth of Field (DOF). Depending on the image subject, you will want to have a shallow or deep DOF.
The aperture which controls the DOF is indicated with an “f” and a number. The number usually ranges from f1.4 to f22. Confusingly a larger number indicates a smaller aperture. The maximum possible (i.e. widest) aperture of a lens usually ranges from f1.4 until f5.6). The narrowest is usually f22 for all lenses.
What to use when?
If there is not a lot of light, you will need the wider aperture, otherwise the image will simply be too dark. Even if there is a lot of light, you might want to use the wider aperture, because the object will look better if the background is blurred. Here are two images if Bumphead parrot fish with natural light.
This image has a narrow aperture (f5.6). The depth of field is quite deep and this is why you can see all three fish relatively sharp.
This image has a very wide aperture (f1.8) and this makes the foreground and background blurry. The fish seems to pop out of the image and the eye is less distracted by it. There is a risk however that not even the whole subject is in focus, specially when the subject is very close to the camera:
As you can see from the above diagram, with the same aperture, when focusing on an object closer to the camera, the depth of field is getting narrower. Specially small, but elongated subjects like pipe fish are hard to get into focus at low light:
This image has an aperture of f5.6, so the same as the first image above with the deeper depth of field. So at a distance, the depth of field ranged several meters, but close-up, it was not even enough to get a 5cm long fish into focus.
This image has an aperture of f22 to guarantee that the whole fish is in focus. It was possible because I use a strong flash that has no issues illuminating an object so close to the camera. However, you can see that the background is also quite recognizable. Luckily, in this image, the background is not very distracting so it does not matter.
Variable vs. fixed maximum Aperture
Most zoom lenses change their maximum aperture when you zoom in. A lens will have the maximum aperture indicated on the model. So a standard zoom lens might have an aperture of f3.5-5.6. That means that at the maximum wide angle setting, it has a maximum aperture of f3.5 and when zooming in fully that reduces to f5.6. So be aware that getting a shallow depth of field or enough light will be always more challenging when you zoom in on your lens. There are some more expensive lenses where the aperture is constant f2.8 throughout all zoom factors, but those are usually limited to DSLR cameras.
The creative choice
While the narrow DOF helps to distinguish the fish from the relatively distracting background, it also prevents us from having the whole animal in focus. What the image is supposed to look like, is anyone’s own choice. You can narrow the focus to the eyes in order to blur and therefore hide the background even more. You can shrink the aperture further and increase the DOF so that the whole fish is in focus but that will also make the background even more visible than above. Ideally, you take 2-3 shots with varying aperture and then pick what you like. The main issue will be that to use a wider aperture, you also will need more light.
Continue reading in Part 2.
Photography is a very wide subject and depends highly on the expectations of the photographer. Just look at the huge gap between what someone might consider a casual snapshot of their one dive during a holiday and what we might see as award-winning shots in a national geographic magazine.
If one wants to start with underwater Photography, managing ones on expectations and understanding the obstacles to fulfill them is essential. There are too many divers who think that the only thing that separates them from shooting photos like those in magazines is a higher limit on their credit card. And they could not be more wrong. If you have certain aspirations on the quality of an image, it is more important to know what kind of pictures your current gear cannot take and try to make the best of it instead of blindly upgrading your camera. The more you upgrade your camera, the more options on how to take a photo you add to your potential portfolio. But that does not mean that you also know how to take those photos. Let me give you some details on this.
Why camera quality matters
First of all, photography is a skill of understanding and managing light. What does that mean? It means that we have to try to get as much light as possible on the sensor of the camera. If there is too little light, the quality of the image will degrade. When we shoot photos in bright sunlight of things that stand still, the camera can gather as much light as it needs to get a nice and sharp photo. Under water however, it’s dark more often than not and mostly darker than your eye tells you since it’s so good at adapting to the darkness. So the camera needs to point longer at a subject to let in more light. If the subject then moved (as fish often do) or if the photographer moves (since he’s drifting in the water), the image becomes blurred. So you will need more light, with the help of a strobe. But the fish still moves and we want to get it when it’s in a nice position. So we need a good auto focus that can track the fish and a fast camera shutter that does not have a delay between pushing the button and taking the photo. So in other words, a more expensive camera and a more expensive flash setup will – just by technical capability – give you better photos.
Further, more expensive setups will usually also give you a higher versatility. If you want to have the options to shoot with all kinds of lenses, good and bad light, have a very high versatility in picture style and in different situations and subjects, you will not get around a camera at least with interchangeable lenses if not straight a DSLR.
However, there are a lot of situations where a small, compact, fixed-lens camera will get you the same if not better pictures than a more expensive setup. For example, the Olympus TG series has a microscope mode that is very powerful for macro images. You would need to invest into much more on a DSLR to get the same image with the same enlargement. The drawback of course is that the limited settings on the Olympus TG will mostly result in only one available picture style, even if the quality is very good.
Why more expensive cameras don’t guarantee better photos
Cheap cameras have one major advantage over expensive ones: They are simple. They have by dimensions less settings, shoot best in auto mode, are easy to setup and to maintain. On top of that, more expensive gear usually is bought by specialists. So the cameras also are made for more specialized purposes such as studio or action photography. For example a Canon 7D is made for sports, a Canon 5D is made for studio photography. While they both can do either much better than a cheap point-and-shoot, you will have to use mostly manual settings on a Canon 5D to take proper high-speed shots of a sports event since the default shutter time on this model of camera is often too slow for even hand-held operation unless you manually take control of it. So unless you know what all the buttons on the camera do to your picture, and unless you want to take the time under water to change the settings for (almost) each picture you take, you are better off with a simple, automatic, point-and-shoot. This is not only true in terms of the vast price difference and to reduce frustrations that your gear does not yield the expected outcome, but you will actually shoot better pictures with a cheaper camera if you cannot handle the more expensive models.
Where to start then?
It all depends on your aspirations, of course. If you are certain that you want to become a professional photographer within 2-3 years and plan to clock a couple of hundred dives in that time, you might as well start with one of the more expensive models from the beginning. In that case, you will be anyhow willing to read several technical books on the subject, take some classes, get serious about it, in other words. In any other case however, I would highly recommend you to take advantage of the fact that most camera models (except the bottom of the range) have very good upgrade capabilities and let your gear grow with your skill. Even Michael Schumacher learned racing on a go-kart and not on a F1 car. For details, I would recommend you to read one of my other articles on this topic.
- Sports cameras / GoPro
These cameras should not be bought for the purpose of dive photography. If you have one already or plan to use it mainly for other activities it might be a good thing to have instead of nothing, but they are not a reasonable investment for underwater photography. The fact that they normally operate only in wide angle, do not have any exposure settings etc, they are rather a minimum equipment for filming if you buy video lights with them.
- Waterproof Compact Point-and-shoot without housing
This is the minimum equipment. The camera does not extend the lens outside the case which makes them very compact. Those cameras are best used with automatic mode, offer very little control over the image produced but are relatively cheap, very small and do not require additional housing. The lack of external housing makes them most prone to flooding. There is usually no manual mode available which makes the optional external strobe not fully effective. The cameras are usually also rugged so can be used during many other outdoor activities without worrying that they get damaged. Further, these cameras often have a special underwater mode that makes colors in images with little/without flash look a bit better.
Pros: Ultra-compact, low cost, versatile use for all kind of sports
Cons: No upgrades, no external flash, no manual mode, no RAW image, lowest flood protection, low image quality, only down to 15 meters deep
Best usage: Beginners or casual, infrequent divers who want to remember what they saw with snapshots but do not consider picture quality a priority.
Example: Nikon Coolpix AW130 (ca 350 USD), Olympus TG-870 (ca 320 USD)
- Compact Point-and-shoot
Compared to the above waterproof point-and-shoot, those cameras are very similar but require an extra housing. If they have an expanding lens, the zoom and low-light capabilities are often better. So generally it can be said that you get a better image quality at the expense of the ruggedness, but the minimum price is lower (about 250 USD instead of 350) But here you need to invest into an external housing (around 300 USD). Optionally, you can get a waterproof model as above with an extra housing. This offers double water leakage protection, but also drives the price by about 100 USD. The biggest advantage is that you can invest into an external flash which will give you a much better picture quality than the above even for subjects further away. due to the lack of full manual controls, you cannot make 100% use of that flash however. Further, for the external flash you need more accessories such as mounting brackets. One huge bonus of some of the cameras available are special settings that are not available even on a DSLR such as the microscope mode in the Olympus TG series which are fantastic for macro images.
Pro: Compact, Cost, full flash benefits, special image modes
Cons: No Upgrades except external flash, medium/low image quality
Best Usage: Divers who want to have a decent picture quality on a budget who want to shoot in automatic mode, special occasions (e.g. macro)
Example: Nikon Coolpix S7000 (250 USD) with Ikelite Housing (350 USD)
Waterproof with case: Olympus Tough TG-5 (ca 450 USD) with Ikelite Housing (ca 300 USD)
- Advanced Point-and-Shoot
Compared to the above Point-and-Shoot, those cameras are bigger, offer full manual controls and RAW shooting mode with a fixed lens. They have much better low-light & auto-focus capabilities, but still no real camera upgrade-capabilities due to the fixed lens. The fact that one has full manual controls however allows the full benefit of a better flash setup. The main reason to go for this level would be the full manual control and RAW image capabilities. The interesting cost factor is that the underwater housing is not much more expensive than for compact point-and-shoot cameras. The housing is also quite compact but even the camera would not fit into a small pocket anymore.
Pro: Manual Control, RAW image, full flash benefits, cheap housing, compact
Con: No upgrades for camera, basic understanding of photography required
Best Usage: Beginners or casual infrequent divers who want a decent image quality and at least take full control of the lighting.
Example: Canon Powershot G7X Mk II (700 USD) with Canon WP-DC55 Case (400 USD)
- Mirrorless cameras
Those are cameras with an interchangeable lens. There are generally 2 types: Those with maker-specific lens mounts and those with open-standard lens mounts. There are 2 open standards for lens mounts, Four-Thirds and Micro-Four thirds (more info here). While maker-specific cameras force you to buy lenses made by the same company as the camera, open-standard systems allow you to buy lenses for your camera from several different makers and therefore you have a wider choice. Since there are quite wide varieties in mirrorless cameras, prices, sizes and upgrade abilities also offer many different options. The big price differences however are caused mostly by the material of the housing (plastic or metal). The fact that you can use interchangeable lenses gives you a much better image control and quality as well as specialization for certain subjects. The price here has to consider additional cost for various lenses since the default lens normally does not offer very high image quality compared to what is possible with the available other lenses.
Pro: Manual Control, RAW image, Interchangeable lenses, relatively compact
Con: Housing becomes more expensive, needs more space
Best Usage: Frequent diver with photography skills who want to be able to customize the setup for specific situations and have a really great but still portable camera for many different usages.
Example: Olympus PEN Lite E-PL7 (550 USD) with Olympus PT-EP12 Housing (800 USD) and optional lenses (300-800 USD)
- DSLR cameras
DSLR cameras have a massive increase in size and costs compared to the above models. The more money you spend, one specializes for very specific usages (macro, wide-angle etc) which reduces flexibility but takes greater advantage of the maximum available increased image quality. One does not need to only buy a camera, a lens and a housing but also specialized domes for the lens currently used. The increased quality however allows to take great photos in challenging situations (e.g. fast fish in the distance) but also requires much better knowledge about photography to really benefit from the better equipment.
Pro: Maximum quality and specialization possible
Con: Very bulky, expensive, good knowledge required
Best Usage: Semi/Professional photographers and frequent divers who want to possibly earn money with their photos.
Example low price: Canon 100D + Ikelite housing (ca 1’650 USD)
Example high price: Canon 5D MKIV w/o Lens (3’300 USD) + Nauticam Housing (3’800+ USD) + Lens
As with all camera questions, be it on dry land or under water, the best camera is the one that you have with you. If your camera is too big, too difficult to handle, to expensive (so you are afraid to check it in at the airport for example), it’s a bad camera – for you. So please keep that in mind when reading the following. You have to decide for yourself what you are willing to carry around.
In the same aspect, the bigger the camera, the more complex it becomes and the less you can rely on automatic settings. The general rule of thumb is that if you do not know why you cannot get decent photos out of a small, simple camera, chances are that you will struggle even more to master a bigger, complicated one.
Last but not least, this article is about photography, not videography.
When deciding to buy a camera, there are – specially underwater – some general considerations to make. Many of them also apply to dry photography, but underwater has it’s own additional issues that come on top of most of the dry photography topics:
Prices vary greatly and there is no limit on the top. Assuming you buy everything new, the minimum starts at about 350 USD. This investment has to be considered in the context of upgrade ability however. If you need to throw everything you have away and buy all new from scratch once you want to get something better, the overall cost over time might be higher. Higher end models have more variable costs due to the ability to buy not only a camera and a housing, but also different lenses. For certain models you can also chose between plastic and metal housings which considerably drive the price upwards. So you need to decide if you want to start small to try it for the first time and then maybe keep something small & simple, or if you want to make an initial larger investment and build on that overtime. More info on this below.
- Upgrade ability
There are very cheap and easy to use point-and-shoot compact cameras that are however not able to be upgraded at all. You can get an external flash, but the camera is what it is. If you want to get something better, you need to throw the old one away and get a new one. This is the right thing if you either know that you won’t want to invest more into the hobby within the next 5 years or if you have a good use for the old camera when you buy something better. If you want to get the most value out of your investment over a longer time period, I would suggest getting at least something with an interchangeable lens.
- Flood protection
It can – and most likely will – happen to everyone: You do something wrong and your camera lets water in during a dive. Or you simply use your equipment long enough until something fails. Not all cameras can be serviced in a way to 100% exclude eventual material fatigue. While flooding is not necessarily the end of your camera, there are some models where the chances that the camera will survive are basically zero, and others where your investment is much better protected. A simple waterproof point-and-shoot for example has a lid for a battery cover. If that as a sand grain, a salt crystal or a hair on it, water will enter the lid and will be immediately inside the camera beyond your reach, on the electric parts. If you have a case around your camera, a single drop will be first inside the case, on the camera surface, and you need to have much more water in the case to affect the camera at all. It can happen that a leaking case might only let water in while you are between 1-5 meter depth, since further down the pressure is high enough to push the lid shut so hard that no more water enters. In other cases, the case will leak only at greater depth. It all depends on the reason and location of the weak spot.
The simpler the camera, the less control you have over the resulting picture. That might be fine when you start off, since you might not know a lot about aperture, ISO and shutter speed, but when you are trying to achieve a certain effect or are unhappy with the way your photos look like, you need to be able to use manual settings in order to affect the result. If your camera does not give you full manual settings, even buying an external flash might not improve your pictures a lot since the camera will not allow you to change settings to make full use of the additional light. If you want full control, you should have a camera that has a “M” setting, or at least a “S” and “A” mode (Speed and Aperture priority). Further, RAW image capability will significantly improve your colors under water. However, as described in the introduction, more controls are only good if you know what you are doing. If you do not know how changing all the dials on your camera impact the photo, you will either use the wrong settings or simply use the automatic modes, in which case the result will be the same for a small compact as for a big DSLR.
A better camera will make it easier for you to shoot different type of photos – at ever increasing cost however. A small camera for example might allow you a bit of zoom and wide angle as well as a simple macro mode. A medium sized camera will allow you to insert 3-4 different lenses into the case and attach different “wet” attachments outside for wide angle or macro. A big DSLR will allow you to attach a dozen different lenses to the camera but you will have to buy different domes (exchangeable fronts to accommodate different lenses) to fit them. The lenses will be much more expensive and the domes as well however. Changing the lenses however is only possible on dry land, so if you go with a macro setup into the water, you are stuck with it for the rest of the dive.
The biggest quality improvements that you get with a better camera are faster auto focus and reaction time (very important for fast moving fish), low light capabilities (important for things that are too far away to be affected by a flash) and of course resolution (if you want to print photos larger than a A4/letter format.
- Size / Weight
Referring back to the disclaimer above, the best camera is the one you have with you. The size and weight of underwater equipment can expand dramatically with the decisions you make. Sizes vary from compact, waterproof point-and-shoot cameras that will fit into your pocket, over well equipped interchangeable lens setup with strobes that fits into a carry-on luggage up to large DSLR with many lenses and their enclosures that require a full-sized luggage. So consider that you will also need to invest into transportation equipment, carry the camera around on dry land and require space in your dive resort to service it. Also, larger cameras have considerably more maintenance requirements, more things that can break, batteries to charge etc etc.
What you want to shoot? While cheap cameras offer some zoom, wide angle and macro modes, the capabilities of those are quite limited. If you invest into a better camera, you can attach different accessories for different types of photo. Those include different lenses, diopters, flashes and more. Be aware that if you buy a fish-eye lens for a DSLR you also need a fish-eye dome/lens cover for your underwater case. Medium price cameras have wet attachments to change while under water, but if you want to use more professional equipment you will have to make the decision before the dive. Further, if you want to take photos of fast moving things, a good auto-focus and a fast response of the camera can be all that prevents you from taking a decent photo. Cheaper cameras will take considerable time between pushing the shutter button and the actual photo.
It’s dark underwater. Very dark. Unless you shoot in snorkel-depth during a sunny day, you will need additional light, unless you are fine with a picture that has only one shade of green or blue and no other additional color. But even then will still get only a blurry, very dark image in depth below 15 meters. So you will very soon need to use a flash. Since light does not carry very far (see the inverse-square law which applies to light), a small, internal flash on a compact camera will not help you to change the light situation on anything more than 50cm away from you. Actually, a small strobe directed at something far away will make the image only worse since you will illuminate all the plankton between you and the object and create so-called back-scatter (imagine shining a light into fog that makes you see more of the fog but not what’s behind it). So the further away an object is, the better your light setup will have to be. Same goes if you go deeper, since it’s darker down there.