sony-a7rii-imageSo what is one-third smaller, lighter, has a fraction of the moving parts and almost twice the resolution of my other cameras? It is one of the newest generation of mirror-less, full-frame, interchangeable lens cameras - MILCs. Continue reading "The MILC Revolution"
For the body size and handling, it’s really a nice camera for the right person. I can’t use it for my general shooting for several reasons but if I want a stealthy UHD camera, this one just might fit the bill. At a price below $900, I was stunned just how good it actually was.
The IQ (image quality) of the camera for a still is pretty good, though it’s not a higher end Nikon or Canon. Don’t be fooled. In dark areas at low ISO it’s easy to see the noise. A huge zoom lens just won’t have the resolution for stills. For most, they’ll be amazed. But if you’re discerning, you’ll be only “okay” with the shadow performance.
If you click on the image on the right, you can see a small sized sample of the full image. The red box shows the 1:1 sample area of the image on the moose hide. For as good as the image looks in full screen, when you get down to the nitty gritty, you’ll see it’s “okay”. I didn’t have time to do a MTR test or anything, but those don’t translate well into “what does it actually look like” terms.
But for video quality you get a very nice image. I was pretty amazed to see it on an iMac display, even though the image was interpolated. It was just clearer than I’ve seen HD. Really, it looked like HD played on a 120Hz TV display. That was the look. The video samples were shot at 60FPS, so perhaps that helped. It really looked like the real thing. I didn’t expect it to be that much better than HD. But if you stack up a 3-chip HD camera with better dynamic range against a limited range, small sensor like this, you might be pressed to tell the difference. Again in the shadows there will be noise. The again, what do you expect for a small form factor single chip camera?
The aperture goes from about f/3 to ONLY f/8. That’s really miserable for photography. Nature of small sensor cameras. Even though the specs claim f/2.8 to f/11, in the shooting I was testing it with, it only really gave me f/3 to f/8 to work with. That’s a tough one, especially in full daylight shooting.
That zoom and optical stabilizer is awesome. I’d love to have something that goes from 25mm to 400mm and does a real good job on my D800. If I did, I could dump a bunch of other lenses. But I’d need it to be f/2.8 and have it go to f/22. Oh well, I can dream.
We had a snow shot with moose and it worked pretty well. But the snow on the mountains was blown out in the video with zebras set to 95%. Again, it’s not a D800 but it’ll blow away your little basic point and shoot. But I think my Sony RX-100 probably still beats it for dynamic range.
The electronic viewfinder – not bad for a video camera, okay for landscape shooting but poor for sports/action/moving things. When you pan/tilt, you get an image jitter. The swim is very small but the smearing in the image will irritate you if you shoot an optical DSLR. EVF (electronic view finders) aren’t there yet. I worked at a digital night vision company where we went to great efforts to have zero swim, jitter or anything else and this isn’t even close. Then again, those systems were $60,000 and this is $900. You get what you pay for.
The info in the viewfinder for a video camera is very nice. It fits the bill of shooting things where a video camera would get you into trouble. For the price, the image quality is pretty amazing. Is there better dynamic range and such out there? Yes, The GH4 and upwards. But for what this is going for, it really makes UHD accessible.
The switch to go from zoom to MF – not a fan. 2 rings are more expensive, though. There’s the zoom rocker on the shutter release. Eh, it’s under a finger, so it feels like a little point and shoot zoom for the video camera it’s designed for.
The fully manual video camera mode – thank goodness! Not allowing me to control Auto-ISO ruins other camcorders/DSLRs. Locking down exposure is critical if you want professional-looking images.
The different programmable function buttons are nice for getting what you want. Some of the switch modes like focus control are appreciated. They’re not in ergonomic places like my D800 at all. There are buttons which are appreciated on a video camera but the layout leaves lots to be desired. Like all things, it’s something you get used to.
The autofocus – amazingly fast. I’m not sure what they put in there but it must be a hybrid phase/contrast focus system because it matches my Nikon D800 focus speed quite easily. However, when you need to control focus points, that’s where it falls apart.
You’ll need lots more storage to use UHD on this camera. Your puny little 320GB drive will be gone in no time shooting with this. Think 2TB drives minimum. Why do I say this? I’m editing my film, Antarctic Tears, which is a feature length film. And it eats up 228GB of my SSD drive. And that’s shot in HD. This camera has almost 4x the resolution. Even a 500GB SSD won’t even come close to supporting a feature length film. 4k/UHD video is what HD was to our computers 10 years ago. Be ready to spend a LOT of money if you want to really work with this.
Major video shooting issue: This thing has no earphone out. That is one major failing. Why in the world they left this out is beyond me. Perhaps Panasonic is trying to push you into a higher end camera. You might be able to use the AV out and cobble something together. Who knows w/o that cable.
If you don’t have ears on your video camera, you’ll realize only after the shot is over what went wrong. I can pipe audio through my ZoomH4n and listen there, as I can use that as my XLR input, but still. No, this doesn’t have XLR. Of course not.
ND filters for video – buy one. You’ll need one. Or two. For a 3-stop ND, I use this Hoya filter.
The batteries seem to konk out pretty quick, but we were shooting at 10 degrees F with wind chill. Buy more batteries.
You’ll need an UHS-1 SD card for it. UHD video eats up a LOT of card space. I hope you bought a spare hard disk or three. Editing this video – get Rocketstore Thunderbolt enclosure with a SSD drive with a fast computer.
Thank you to Sava Malachowski of Sava Film and Open Range Films for the sample images and video. He had excellent footage to sample and work with in tough conditions, shooting in a Wyoming winter with dark animals and bright snow. There’s not much tougher.
It has been a while since I have written about the technical aspects of photography and I thought it would be good to dive into a discussion about the broad field of wildlife photography. It is a big subject so I'll cover it in two separate postings.
I moved to Jackson, Wyoming last year primarily to be closer to nature and to the amazing wildlife in this part of the country. As a 'nature photographer,' I enjoy all aspects of outdoor photography from landscapes to wildlife to macro-photography, but it is wildlife that really gets me excited. When I write about wildlife photography I really mean WILD-life - not pets, zoo animals, or critters in cages of any sort, but real wildlife out in the open, fending for themselves. I like all sorts of wildlife from large carnivores to birds, grazers, cute little rodents, insects and other invertebrates and each of these families of critters bring different challenges to the photographer.
There are really three 'styles' of wildlife photography and each has its individual rewards. First, and most common, are wildlife portraits. You find a great animal out in a natural setting and are close enough to capture its image close up. Second, there are the beautiful scenic shots (below) with a magnificent animal in the foreground. Third, are the behavioral shots (see blog cover photo)when the critter you have found is doing its thing in an animated and interesting manner. The preparation and gear required to capture each of these styles of images is modified by the physical size of the animal you are shooting.
It goes without saying that a quality digital single-lens reflex (dSLR) camera body is the choice of most wildlife photographers but that doesn't mean that you can't capture great images with a super-zoom or even a point and shoot camera. I remember a few months ago staking out a black bear in Yellowstone for over two hours. I had a 600mm super-telephoto lens mounted on a sturdy tripod ready to go but the bear stayed in the bushes always partially concealed from my view. I packed up ready to move on when the bear took off across the road in front of a car giving the woman in the car a better shot with her phone camera in 20 seconds than I had in hours that cold Yellowstone morning. But good photography requires more than luck - you want to be able to capture good images, reliably, under many conditions. The dSLR is the best choice.
The next issue is the selection of lenses that will give your camera the best image. Wildlife photographers are always looking for the "big glass" but there are two types of 'big' that you must consider. Many times when photographing wildlife you cannot get as close as you would like to be - either because the subject will leave your field of view or the subject is bigger than the photographer and, therefore, demands space. So big lenses are usually part of every wildlife photographer's arsenal but how big is necessary? The answer is, it depends.
Many (most?) times you will want to 'fill the frame' with your subject. So the smaller the subject the closer you must be or the larger your lens must be. Generally, most start with a moderate telephoto lens in the 200-300 mm focal length range. These lenses are small enough and light enough to carry for a significant distance and yet will give a significant 'reach' to your subject. If you are using a crop sensor, rather than a full frame sensor, camera you will see even a smaller angle of view giving the appearance of more magnification. Typically, most APS-C size sensors have a 'crop factor' of 1.5x or 1.6x thus increasing the effective focal length of your lens by the crop factor. Effectively, you get more bang for your buck using a telephoto lens on a crop sensor camera body.
Another way to extend the reach of your lens is by adding a tele-converter (sometimes called a tele-extender) between the lens and camera. These converters increase the effective focal length of the telephoto lens that is attached by a factor of 1.4x or 2x. Doing the math, you can see that a 200 mm telephoto lens on a 1.6x crop sensor and a 1.4x teleconverter give you an effective focal length of 448 mm (200 x 1.6 x 1.4). A 2x tele-converter would increase the effective focal length even more to 640 mm. The increased effective focal length with a converter comes with a significant cost - reduced light to the sensor. A 1.4x converter reduces the maximum aperture of the lens by 1 stop and the 2x converter reduces it by 2 stops. This raises the second requirement for wildlife lenses - they must be 'fast.'
Generally, the best shooting of wildlife is in early morning and late afternoon as the sun is rising or setting. This means a high likelihood of shooting in low light situations. Low light means you will need a large aperture, long shutter speed, or high ISO for proper exposure. (See the Exposure Triangle, 2/21/13, and Where to Start with Exposure, 2/27/13 blog posts.) A long shutter speed is almost never a good option using a telephoto lens because of the chance of image blur due to 'camera shake' or movement of the subject. The rule of thumb is that the shutter speed should equal or be faster than 1 / effective focal length. So your 200mm lens on a crop sensor camera with a 1.4x converter means your slowest shutter speed should be 1/640 seconds or more practically, 1/1000th second. That is fast enough to eliminate blur from camera shake and to freeze (slow) movement of your subject but how do you get enough light to the sensor? The answer is a large aperture. So the second 'big' in wildlife lenses is a large diameter aperture - ideally f/4 or larger. The large aperture allows more light to reach the sensor in the time the shutter is open. Unfortunately, a large aperture is the major cost of a lens - more glass equals more money.
We will address the last of the exposure issues and other ways to improve your wildlife photography in the next posting. Until then happy shooting.
We are getting you "geared up" for an amazing experience in nature and wildlife photography. I have discussed camera essentials, lenses, and filters in the last postings. This time I want to wrap-up the gear you will need by discussing some of the accessories needed to photograph in the wild.
By now you know or have the big things needed to capture digital images, but as with most endeavors, the devil is in the details. So what is in the camera bag or backpack that keeps you taking great photographs? The first thing is the bag itself. There are 3 or 4 options for carrying your gear in the field. The first is going bare with lens and camera for a specific shot. This works sometimes but nature is not always predictable and more times than not, she will offer you amazing and totally unexpected opportunities, if you have your gear along. A second option is a traditional over-the-shoulder camera bag. This is nice near the car but usually doesn't lend itself well in the back country or down a long trail. A third option is a gear vest and/or a fanny pack. These were great in the film days when you needed many rolls of film and a means of separating fresh and exposed film but I find these are too small to carry extra lenses that I might need. Option four is a rigid travel case that works great in the city but has little role once you are outside your car. Finally, my choice for outdoor work is a purpose-design SLR back pack such as those made by Lowepro and Tamrac. In my Tamrac Expedition 5x pack I can carry a spare camera body, 5 lenses, and all of the accessories I will discuss later. It has an integral tripod holder and many tie-points to strap a water bottle and additional gear. I added a padded waist belt and can haul about 30 pounds of gear for several miles in reasonable comfort. Everything is padded, adjustable, and easily accessible.
Nothing can ruin a photo shoot faster than a full memory card or a dead battery. For this reason I carry at least one spare battery for each camera body (and their chargers for both car 12VDC and AC mains (110 or 220VAC) with the proper adapters. I also carry a 32GB memory card in the camera and several 16 GB spares. I can shoot more than 1,000 high-resolution RAW shots with one battery and card.
I have a velcro filter case strapped to one shoulder in which I carry a variable neutral density filter, circular polarizing filter (CPL), and spare UV/haze filter. In the pack I carry a rectangular 2-stop hard-edge, graduated neutral density filter, holder and adapters. These filters usually get me through most difficult lighting situations. I also have a 5-way, collapsible reflector to help bring light to the shadows. At this time, I do not carry a flash/speed-light/strobe with me in the back country. I probably should but I find the pop-up, in-camera strobe and the reflector serve me well. Someday maybe I will find space for a flash, and a flash extender, flash filters, and spare flash batteries, and a bigger backpack.
In the bag I also carry a 1.4x teleconverter and a set of 3 extension tubes. The teleconverter increases the range / magnification of my telephoto lenses and the extension tubes can be used to reduce the closest focus point of all of my lenses. These are especially useful for close-up and macro shots.
Don't forget to carry a remote shutter release with you in the wild. These come in several varieties from mechanical, to electrical, to infrared, to radio controlled. The important thing is to be able to fire your camera without touching it and causing motion (camera shake) during long exposures or high magnification shots such as macro or long telephoto shots.
Finally, in the bag I carry cleaning gear including a Lenspen brush, several microfiber cleaning cloths, lens cleaning solution, a blower, and lens paper. These essentials usually get me through any field clean-up operations and keep my optics clean.
Lastly, the most important accessory of all, is your camera stabilization gear - your tripod. Camera stabilization is critical for telephoto shots, long exposure shots, high dynamic range (HDR) shots, panorama shots, macro and close-up shots - did I miss anything? I cannot emphasize the importance of a good tripod in capturing good photographs. Not all shots are taken with a tripod but many are, and virtually all shots could be improved if a tripod is used. Now the reality is that tripods are large, bulky, awkward, and heavy to carry. However, small, light-weight tripods are totally worthless and a complete waste of money. The purpose of a tripod is to provide an absolutely rigid mount for your lens or camera - it must be solid, sturdy, and stable. What choices are available?
One of the first choices in selecting a tripod is the strength defined by the maximum load weight capacity. You need a tripod capable of holding the head, camera, and largest lens you will use. Once you know the weight capacity you need to choose the construction - most tripods today are made of aluminum or carbon fiber. Pound for pound, carbon fiber is lighter, stronger, more durable, and more capable of reducing vibration than is aluminum - obviously, with these qualities, it is also more expensive. Next, you need to consider the maximum and minimum heights at which the tripod can be used. High quality tripods have legs that extend widely to place the camera very low to the ground and straighten to give lift to eye-height. Some tripods have a central elevating column to gain additional height. The center columns often reduce the stability of the tripod when extended and interfere with lowering the tripod for low-level ground shots.
Two other choices are available in tripod construction - the number of leg sections and the means of securing the leg extensions. Most brands of tripods have both 3 and 4 section leg extension models. The 3 extension models are usually quicker to set-up, stronger and sturdier but also fold to a longer storage length. The extensions can be secured by either flip-locks or twist locks. People tout the advantages of both but as long as the locks are strong, I don't think the type of lock makes a difference. Some tripods offer padded feet with extension spikes for greater stability.
Sometimes a monopod is a useful camera stabilization tool in the wilderness. It is no substitute for a good tripod but the monopod can reduce fatigue and add stability to action shots such as sports or birds in flight. Monopods have aluminum or carbon fiber construction and are available with a 3 or 4 section leg. Some tripods have a detachable leg that works as a monopod. Some inovative photographers have modified their monopods to be used as a walking stick or their walking sticks to be used as a monopod.
As if tripods were not difficult enough, the head that joins the tripod to your camera or lens is even more complicated. Older tripods used almost exclusively a "pan and tilt" head to control the three planes of rotation of the camera on the tripod. These heads are modification of what was used for video and movies. These heads require either two or three adjustment knobs to change the camera position. Most still photographers in recent years have adopted a ball-head mount. The ball head allows faster re-positioning by loosening only one adjustment knob to move the camera in all three planes. The ball-heads come in several sizes and the larger sizes usually support the most weight and give the greatest stability. There are many designs of the ball-heads and costs vary widely. The third type of head used by nature photographers is the gimbal head. This is a significantly larger mount that is necessary for today's super-telephoto and very large aperture lenses. The gimbal mount keeps the center of gravity of the camera and lens at the exact center of rotation so there is no resistance to movement and no tendency for the heavy lens to drop downward as it can with a pan-and-tilt or ball-head mount. These gimbal mounts are fairly heavy and quite expensive.
The last accessory is a quick-release fitting between you tripod head and camera or lens. The quick-release comes in several styles but the ARCA-Swiss style is becoming an industry standard. The quick-release allows a strong and stable connection between your camera/lens and tripod but yet allows the camera to be removed quickly for hand-held shooting. The last thing you want to do to your camera is to screw it off and on your tripod and risk damage to the camera or lens. The quick-release is a good solution. Get a system for your tripod(s) and a mounting plate for each camera/lens with a fitting.
With all of the complexity of tripods and heads, you might ask what do I use? Unfortunately, the answer is all of the above. For years I got along with a Manfroto carbon fiber tripod with center column elevator, 4-extension, snap-lock legs, and a ball-head. It was a perfect union for the nature photographer who like to hike deep in the woods or high in the mountains. Then I got my 600mm f/4 super-telephoto lens. This monster 12 pound lens simply could not be used safely or comfortably on a ball-head so I was forced to get another tripod and head - this time a Sirui carbon fiber tripod without a center column elevator with 3-extension, twist lock legs and a Wimberly gimbal head. This is a rock-stable rig that will hold the heaviest dSLR lenses and cameras made - but, it is heavy. The tripod weighs over 5 pounds (and extends to my full height) and the head weighs another 4 pounds. Add a 3 pound camera and 12 pound lens and it makes you want to give up hiking!
There you have it - all the accessories you will need to accumulate for serious nature photography. So before you dip your toe in this water consider the merits of a nice 1.5 pound point-and-shoot camera with a super-zoom lens - it does a pretty good job and will always be with you in the wild.
In the last posting we wrapped up the discussion about lens selection and ended with some comments about filters that are used with your lenses to create special effects or solve difficult lighting problems. We will pick up on that topic in this posting.
In the ancient days of 35mm film, many filters were considered to be essential for good photography. In the pre-digital age tinted filters were needed to adjust color temperature for different films but today these adjustments can be made easily in post-processing software so it is rare to need color adjustment (often called warming or cooling) filters.
UV / haze filters are often sold to buyers of new cameras and lenses to protect the front of the lens from physical damage. These filters are said to help clear haze from the sky on landscape shots but really have no appreciable benefit over adjustments to the image that can be made in post production software. Low quality filters can degrade image quality and induce flare from back lit subjects and should never be used with high quality lenses. High quality filters may not harm the image quality but may add $100 to the cost of each lens and while they keep dust and water off the front lens, their ability to protect from physical damage is questionable. I use them on some of my lenses but am not sure that the $500 cost was worth the price. I personally believe that a lens hood is better protection and will not degrade your images.
A circular polarizing filter (sometimes called lens or CPL) is probably the most important filter for outdoor photographers. The polarizing filter will cut through haze, reduce reflections from water or shiny objects, saturate the sky, and enhance clouds better than any post-processing software and produces just about the only image changes that cannot be achieved in software. The CPL is actually two filters mounted together in a rotating ring that can be turned for the desired effect. The CPL works by aligning light waves and thus reducing glare. The filter has its greatest effect when it is 90 degrees to the light source so it must be rotated to the proper position before the image is captured. The filter should be used in almost all landscape photography and shots of still waters. The CPL has two side-effects. First, it reduces exposure by about two stops meaning that aperture or ISO will need to be increased or a larger f-stop will be needed compared to a shot without the filter. Next, the filter can cause some saturation abnormalities when used with wide-angle lenses. Because the filter is most effective when turned 90 degrees to the light, a wide-angle lens may 'see' variations in saturation of the sky. High quality CPLs are quite expensive and should be sized for your largest diameter lens. Adapters are available to match the CPL with lenses of smaller diameter. High quality CPLs are very thin and do not induce vignetting at the corners of you shots as may occur with cheaper, thicker filters. High quality CPLs are coated to reduce lens flare.
Sometimes, nature photographers need to reduce the amount of light reaching the sensor to achieve a proper exposure in bright daylight. A classic effect is to use a very long exposure 1/2 to 4 seconds to create a dreamy smoothness to a waterfall or other moving water. When the ISO is reduced to the minimal sensitivity and the aperture is reduced to the smallest opening, sometimes in bright daylight, the slowest shutter speed to properly expose the image is 1/60 - 1/100 second - too fast to get the desired effect of smoothing the water. Here is where the neutral density filter comes to play. A neutral density filter is a neutral gray filter that reduces light to the lens without altering the tint or hue of the light. The filters are rated by the number of stops (halving) of the light caused by the filter. Typically a 2-4 stop filter will allow the light reduction that is needed for the exposure time you want to use but sometimes the light needs to be reduced by 6-8 stops. Neutral density filters can be stacked to achieve an additive effect on exposure reduction. Stacking more than two filter may cause vignetting of the corners of the image. Another solution is a variable neutral density filter that can be adjusted from 2 to 9 stops of light reduction. These seem to work well as a cost-effective alternative to having multiple fixed neutral density filters. A third solution is a rectangular external gel or glass filter added to the end of your lens. Multiple filters can be stacked in the holder to achieve the desired effect.
Another very useful filter for the landscape photographer is a graduated neutral density filter. These filters are usually rectangular glass or resin mounted in a holder on the end of the lens. The filter is graduated in that the bottom is clear (usually) and the top is progressively more dense. The purpose of the GND filter is to reduce light from a bright sky while maintaining the light in the foreground. The filter is simply moved up or down after the shot is composed so the light reduction occurs above the horizon in the bright sky. These filters tend to be pricey and are available with soft or hard edges meaning the darkening occurs abruptly or gradually. I prefer the hard edge set on the horizon. They are also available in a 'reversed' form for certain shots with a bright foreground and may be stacked to achieve the desired effect. GND filters are rated at values of 0.3 (1 stop), 0.6 (two stops), and 0.9 (three stops) of light reduction. The two stop reduction is most useful but at times needs to be stacked with a second 1 stop filter. They may also be stacked with a polarizing filter or plain solid, neutral density filter. The glass filters are easily broken and the resin (plastic) filters are easily scratched so while very useful, GND filters can quickly become very expensive. The screw-on circular GNDs should never be used. Although cheaper than the rectangular filters, they drastically limit your ability to properly compose your shots since the graduation is at a fixed point on the lens.
The list of specialty filters goes on and on. These filters can be used to help tone black and white images, induce color (hue) shifts, achieve white balance, or produce unusual light effects such as star or other shape effects at points of light. None are necessary to the nature photographer but they can produce interesting a visually unusual effects.
So by all means obtain CPL and ND filters as you will definitely find a need for them. As for the others, experiment with their use and when you have some more money to blow on photography gear, why not?
In the last posting, I discussed the various general types of lenses - normal, wide-angle, and telephoto - and the pros and cons of fixed (prime) lenses and zoom lenses. Now, I would like to get more specific about the selection of focal length and add some specialty lenses and lens accessories to the mix.
The focal length of a lens is the distance from the optical center of focus within the lens to the plane of the image sensor in the camera. Focal length is usually measured in millimeters (mm) and the longer the focal length the greater the size of the image on the sensor (sometimes referred to as magnification.) I mentioned that a lens with the field of view of our eyes in approximately 50mm when projected on a full-frame (24x36mm) sensor. However, most cameras use a sensor smaller than full-frame that is called a crop sensor. The camera is designed so that the crop sensor still 'sees' the full image so, effectively, the image is magnified by the crop factor of the camera. Typically, point and shoot cameras have a very large crop factor (from 2 to almost 6) so that the effective focal length of the lens is much greater than the measured focal length (compared to full-frame sensor.) This is why many point and shoot cameras are referred to as 'super-zoom' cameras and their zoom range is defined as the magnification beyond the shortest focal length of the lens (12x, 15x, 20x and even 30x.) Digital SLR cameras do not use this 'magnification' terminology but rather relate the effective focal length to that of a full-frame sensor.
So how does crop factor influence the effective focal length of the lens. Many dSLRs from Nikon, Sony, Samsung, and Pentax have a crop factor of 1.5 while most Canon dSLRs have a crop factor of 1.6. The crop factor is multiplied times the actual focal length to obtain the effective focal length seen on the sensor. In other words a normal 50mm lens on a Canon 1.6 crop sensor looks like an 80mm lens. So this 'normal' lens is working like a short telephoto (if you were shooting on a full-frame camera.) This effect has a tremendous advantage for a wildlife photographer who always wants a longer lens to create images closer to the subject. Effectively, a 200mm (medium telephoto) functions like a 320mm lens on a Canon crop sensor camera. A 70-200mm zoom functions like a 112-320mm zoom. This sounds like a real bonus but what if you are shooting landscapes with a wide-angle lens? Now your 24mm (medium wide-angle) lens acts like a 38.4mm (barely wider than normal) lens. This is part of the reason that landscape photographers like full-frame cameras - they can maximize their wide-angle ability.
So when purchasing a new lens you must carefully consider the type of photography you will be doing and the crop factor of your camera to select a lens that will give you the effect you desire.
There are also several types of specialty lenses that appeal to nature photographers. The first is a macro lens. A macro lens is specially designed for a very close focusing distance for its focal length. A true macro lens projects an image of the subject at its full size on the camera sensor - a 1:1 image. Macro lenses come in different focal lengths depending upon how close to the subject you can get. Typically, macros range from 60mm to about 200mm. These lenses are designed for ultra-sharp images captured at very close distances and are often used to shoot flowers, insects, and other small critters. Focusing a macro lens is a challenge because the the very narrow depth-of-field - often only a millimeter or two when wide open (f/2.8.) Depth of field is improved if the lens can be stopped down (f/11- f/32) but this usually means a very long shutter speed or supplemental light using a reflector or flash. Some general lenses have a close-focusing feature they refer to a a macro function. I have used this to advantage on my small Sony camera but it is not a true macro because you cannot focus down to a 1:1 size - mine is more like a 1:2 but it still focuses down to about 3-4 inches from the subject.
Another lens sometimes used by landscape photographers is a fish-eye lens. A fish-eye is an extreme wide-angle lens (6-10mm focal length) that is able to capture nearly a 180 degree view. These lenses cause extreme distortion of the image resulting in curving horizons than are usually interesting and can be very pleasing to view.
With all of the choices of lenses, what is the best general 'carry-around' lens for everyday photography? This is a very difficult question to answer and most photographers will tell you that a 24-70mm zoom is a good all around lens (best on a full-frame camera.) This lens gives you a mild wide-angle to short telephoto perspective and can be fast (f/2.8) and not unwieldly large. I like this lens a lot when I am in town shooting what-ever comes by, but it is not my favorite lens in the wilds. It is generally too short for birds and animals and not wide enough on my crop-sensor camera for great landscapes. It is fast for dawn and dusk shots but I almost always carry 25-30 pounds of other lenses and gear when I hike to take wildlife or scenic shots. Some people like super-zoom lenses (28-300mm) for general work. Often these lenses are slow (f/5.6 or worse) and some lack high quality optics so I have avoided the super-zooms.
Finally, how does one properly accessorize your lens? A lens case is a good thing to keep in the closet at home or to store your lens when you are not shooting, but I never use lens cases in the field because they add unnecessary volume to the gear and it takes too much time to get the lens out of the case. I keep my lenses in my pack with lens covers on front and back to protect from dust and weather.
There is controversy among photographers about using a UV/haze filter to protect the front of your active lens. Clearly, low quality glass in front of your expensive lens can degrade image quality and introduce lens flare on back-lit images so these should be avoided. I have chosen to use high-quality neutral (UV/haze) filters on the front of most of my lenses. It is a high cost but does keep dust off the much higher cost lens. I have never dropped or scratched a lens so I can't (yet) vouch for the protective effect of the neutral filter. Many (maybe most) professionals advise against a neutral filter over the lens. They doubt the protective effect if the lens is dropped and worry about the negative effect on image quality. Almost all professionals use a lens hood on all lenses. The hood protects the front of the lens from damage, reduces the likelihood of lens flare on back lit images, and has no negative effect on image quality. I always use a lens hood unless I need to rotate a polarizing filter or variable neutral density filter or am using a rectangular graduated neutral density filter. These filters will be discussed in the next posting.
Now that you have a new camera and know the basic exposure controls, it is time to get serious about selection of lenses for nature photography. First, understand that brand is not as important as quality and functionality. Generally, it is best to stick to lenses made specifically for your camera body - usually by the camera manufacturer, but not always. Most photographers will tell you that the quality of your glass is more important than the quality of your camera. So what questions must be asked to select the lenses that will help your improve you images the most?
Before you can choose a lens you must consider if you want a lens that will work only for your current camera body or will it work or future camera body upgrades. Most companies make a line of lenses that is designed specifically for smaller, crop sensor cameras. These sensors are smaller than full-frame sensors that are the size of 35mm film (actually about 24x36mm.) All entry-level digital single lens reflex cameras currently use a crop sensor. The crop factor is typically 1.5 on Nikon and 1.6 on Canon cameras (more about crop factor later.) Lenses made especially for the crop-sensor cameras (Canon calls these EF-S lenses) are usually smaller, lighter, and less expensive so they are aimed at the entry-level photographer. While they work well on the smaller cameras (and some are of very high quality), they will not work at all (or even fit on) the high level, full-frame cameras. Other lenses are inter-changeable between crop and full-frame cameras. Canon calls these all around, full-line lenses their EF series. Across the board, the EF lenses are generally of higher quality. Canon also has a special series of EF lenses that are called the L lenses (luxury?) that are identified by a red band around the lens. These are extremely high quality, metal framed lenses, that have improved designs, high quality and exotic glass, and additional weather sealing for professional performance.
The first question in selecting a lens is, what are you going to photograph? If you are shooting exclusively landscapes, your lens selection will be far different than if you are going to shoot birds. Keeping this first question in mind, lets look at some basic issues we all must face when selecting a new lens.
Everything in photography is a trade-off and lenses are no exception. Quality of construction and, most importantly, quality of the glass used is of fundamental importance. There is a huge trade-off because high quality almost always means high cost. Two quality factors easily examined are the exterior construction (plastic versus coated metal) and the lens-to-camera connection (should always be metal, and ideally weather-sealed.) Other factors that must be considered are addressed in the specifications for the lens. Ideally, you want a lens with fast auto-focus and, for longer lenses, image stabilization (or vibration reduction for Nikon lenses.) These features will improve your ability to get well-focused shots with no blur caused by camera shake but also add to the cost of the lens.
The most important feature of all lenses is their "speed" defined by the largest aperture or f-stop. Fast lenses are necessary to freeze motion, shoot in low light, and control the depth of field (DoF.) Fast lenses have a maximum aperture of f/4, f/2.8, or even larger. Since the f-stop is calculated as the quotient between the focal length and maximum diameter of the light path through the lens, it is easy to see that fast lenses (large maximum aperture) are very large lenses, heavy lenses, and expensive lenses. For example, a Canon 400mm L-series f/5.6 lens weighs about 2.75 pounds and costs about $1,300 while its big brother 400mm L-series f/2.8 weighs about 8.5 pounds and costs about $11,500. Maximum aperture is a very big deal!
Another issue to consider is choosing a prime lens versus a zoom. Prime lenses have a fixed focal length and are generally sharper, lighter, and simpler in design. They also tend to be much more expensive because of the quality of construction. Zoom lenses are generally more popular, more complex, and not as sharp. Zoom lenses are also much more convenient for most photographers since they can carry fewer lenses and still frame their shot conveniently from one position. Popularity of zoom lenses makes them sell better and in spite of their more complex design, they tend to be less expensive than their prime counterparts.
Now we come full circle to the first question about photographic subjects and focal length of the lens. The focal length determines the field of view and therefore the 'magnification' of the image. A 'normal' lens gives the approximate view we see with our unaided eyes. The focal length of a normal lens on a full-frame camera is about 50mm (or slightly less.) Lenses with a broader angle of view are called wide-angle lenses and those with a narrower view are called narrow-angle lenses - not really(!), they are called telephoto lenses. Wide-angle lenses are great for landscapes and some close-up work and give the feel that the viewer is immersed in the image. They tend to have great DoF and very close minimal focusing distance. They cause some distortion of the image at close range and are very forgiving in focusing. On the other hand, telephoto lenses are great for wildlife shots and some distance shots. They tend to have a narrower DoF and flatten the perspective of the image thereby removing the viewer from the subject. They tend to cause less distortion and are very sharp but are more critical in their range of focus and minimal focusing distance.
Some zoom lenses cross the line between wide-angle and telephoto. This is very convenient because fewer lenses are needed for a wider range of images but extreme zoom lenses, for technical reasons, tend to be of lower quality and have issues with sharpness and distortion.
In the next posting we will take on the issue of crop factor and its effects on the image and general care and protection of your lenses.