A Page of Resources and LinksAugust 21st will be the big day for this year’s Solar Eclipse—and Jackson Hole is directly in the totality path! The Park Service is preparing for the event with extra staff, one way roads, camping and parking restrictions and so forth. Expect bumper to bumper traffic and all kinds of “issues”. Even with a few potential logistical hassles, this will be a once in a lifetime opportunity for most of us. Luckily, I live in the path so I don’t have much invested in the eclipse. I don’t have to gamble at all! Others will have paid premium prices to be in Jackson Hole for the event—with no guarantee of clear skies. Heavy clouds, and even smoke from area fires, are always a possibility. Barring clouds or smoke, onlookers can expect some of the least polluted skies in the country. Plenty of areas of the country will be in the path of the Solar Eclipse but Jackson Hole will be a hot ticket! Remember—it will be August. Traditionally it is a very hot month in most parts of the US. Jackson Hole’s cool weather and clear skies make it a premier location. NOAA: Ready, Set, Eclipse: As the map indicates, JH is predicted to have a good chance of clear skies for the Eclipse in August (Historical Averages). Viewers originally planning on being in Oregon might rethink their choices. The “clear skies” gamble is much higher there. Continue reading "Jackson Hole’s Great Solar Eclipse!"
I have commented previously about the time spent at a computer in our world of high-resolution digital photography. When I am not out shooting, I am often in the office in Jackson, Wyoming at the computer importing, tweaking, categorizing, editing, and backing up large numbers of digital images. One of the first things I learned was don't try to do this on your average laptop.
Today's high-end digital cameras produce raw file images that easily exceed 25 - 40 megabytes per image. Large multi-layer edits and specialized combined images, like panoramas, can easily kick the file size up to 100 or 200 megabytes or even a gigabyte in size. Handling these huge files takes some serious computing power.
My recommendation for an office / studio computer for high volume editing is a traditional tower computer - usually a high speed model designed for gaming. These gaming PCs have high power processors, lots of memory, a dedicated video processor with additional memory, and high speed peripheral ports to external devices. My office system is based around such a gaming PC and is shown on the cover photo of this post.
Let's take a look at some of the specs needed to handle today's large files and editing software. I have a CyperPower PC available from many gaming PC distributors. The heart of this monster is a 4.33 MHz dual-core processor accessing 16 GB of RAM and driving a high speed video card with an additional 2 GB of memory. This is a good kick-start but the real accelerator in the system is a solid-state drive (SSD) that houses all of the operating system and all software. The SSD is between 4 and 10 times faster than the best mechanical hard drive and the speed is evident when you are opening large files. There is a Blu-Ray DVD / CD drive for loading software and burning preview disks for clients. The traditional 2 TB internal hard drive and 3 cooling fans completes the guts of the tower.
I have chosen USB-3 peripherals. You can use fire-wire and other proprietary connections but I like the ease of use and wide compatibility of the USB connectors. The tower has 2 USB-3s in front and 4 in back along with a few USB-2s for I/O devices like keyboards and tablets. I chose Logitech wireless wave keyboard and wireless 4-button / wheel mouse for general input and control of the machine. Another port is used for a high speed card reader for my CF and HSSD camera cards.
Also using the USB-3 connectors are a series of external hard drives for back-up and additional archiving of images. I use a pair of 4 TB primary back-up drives, a 2 TB travel drive, and a 1T drive with the SSD image just in case this highly reliable device should fail or be corrupted. Another option is a RAID drive with automatic dual-drive back-up. It is on my wish list but the high cost and lack of higher capacity make me stick with the twin 4 TB externals. When a 16 GB RAID device is available at a reasonable cost, that will be the way to go.
The main editing interfaces are a pair of 27" ViewSonic high resolution monitors linked by HDMI to the PC. Two large monitors are almost essential to efficient editing. When I am working in Adobe LightRoom, I use the keyboard/mouse with the interface on the right-hand monitor and a full-screen image on the left-hand monitor. This saves constant switching back and forth to full-screen views after each edit. When I need to open PhotoShop for more advanced pixel-level editing, it comes up on the right-hand monitor above the Wacom Intuos-5 digital tablet. I simply angle my chair a little to the left and pick up the stylus and I am ready to go. When I save the edited image, it drops back into LightRoom on the right-hand monitor and I am ready to move on.
In a nutshell, the keys for efficient digital editing are a high speed processor with lots of RAM and plenty of external disk space for back-ups. Meticulous cataloging and key wording of images and daily back-up of your work should allow you to stay in the field shooting and minimize your time at the computer.
2013 was, by every regard, a banner year for Natural Photography. It was the first full operational year, it was a time for acquiring new, and needed, equipment, gear, and editing software, and it was a year of learning about the region, fellow photographers, and important techniques that will serve me in the future. It was a year of networking with the Teton Photography Group and helping the group mature as an organization. It was a year of monumental wildlife observation and photographic opportunities.
Many people like to look back at the previous year to help plan for the next year. I have observed other photographers posting their "year in review" and decided to look back at 2013 and share a single photograph from each month that had personal meaning to me. These are not necessarily the 'best' shots, or the most successful shots in terms of sales, but rather are those that touched me because of where or how they were made. I hope you enjoy them.
A crisp, sub-zero January afternoon shot looking across Grand Teton National Park taken on the way back home from a day of shooting.
A rather angry Trumpeter Swan scooting across Flat Creek on the north side of Jackson.
I was walking through the woods along the Gros Ventre River in Grand Teton National Park waiting for a herd of elk to cross the river on their migration north when I was surprised by this touching scene of mom and two calf moose.
My first view of the famous grizzly bear #610 only a couple of days after she came out of hibernation with her 3 two year-old cubs and headed for the Snake River in Grand Teton National Park.
Our second trip of the season to Yellowstone National Park and we were treated to a private showing of the spectacular 309 foot, Lower Falls of the Yellowstone River.
Spring arrives in the back country of Grand Teton National Park and the yellow-belly marmots are out to celebrate the warm sunshine and make me laugh at their antics.
On a summer trip to the Black Hills of South Dakota, we took a side trip to Wyoming's Devil's Tower National Monument and shot the monolith at night with the help of some "light painting" provided by a group of other photographers about 1/2 mile away.
Shopping at the Saturday morning Farmer's Market in Jackson, we came upon a rare Eurasian owl being shown by a representative of the Teton Raptor Center. I paused for a "selfie" in the reflection in the great bird's pupil.
A chance of a lifetime came up in the fall when we were asked to help in the Yellowstone Association Bookstore at the Old Faithful Visitor Education Center. We spent almost 7 weeks in the park and found a new viewpoint to enjoy the famous Grand Prismatic Spring in the Midway Geyser Basin.
On one of our many visits to Yellowstone this year we found a pack of gray wolves near Soda Butte and while watching for nearly an hour, this young black wandered practically up to our Jeep, laid down, and gave his blood-curdling howl to the rest of the pack.
Wonders of nature never cease in Jackson, Wyoming. I was in my office editing photos when this poor little Northern Pygmy Owl, chased by a couple of Magpies, crashed into my door. The poor thing was knocked out and on its back and I went out to try to warm it from the cold. It stood up, pupils unequal, and shook its head. Fortunately after about 15 minutes it regained its equilibrium and flew into an Aspen where after about an hour, seemed to recover and flew away.
The mountain goats of Alpine, Wyoming came down early this year due to heavy October snow and frigid temperatures. More than 30 play along the road and on the cliffs of the Snake River Canyon south of Jackson.
More than 25,000 shots taken and almost 20,000 added to my archives in 2013, more than 1,000 new images available on this site and now on Flickr, and these were the 12 with special meaning to me. Please join us on Facebook for more frequent updates. I hope you enjoyed viewing these images as much as I did making them. Happy 2014.
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.
It is hard to believe that it's been more than 6 weeks since my last posting but it is even harder to believe that Natural Photography is 6 months old!
It has been a very busy summer shooting and traveling to unique sites and more of our public lands. (That's my excuse and I'm stickin' to it - for the long delay since the last posting.) On the other hand, the website has been extensively updated with a dozen new photo galleries and many additional photos added to previously existing galleries. The revisions add galleries for new national parks and public lands visits but also add many more specific species and settings in which to locate wildlife photos that may be most interesting to you. Specifically, there are new galleries in the Fauna section for mountain goats, bison, and pronghorn and new galleries for waterfowl, wild canines, small mammals, and, a sure favorite, babies and young-in's.
Besides many more photos from Yellowstone, I have added seasonal sections for our Jackson Hole neighbor, Grand Teton National Park. A recent trip to South Dakota allowed shooting at Devil's Tower National Monument, Mount Rushmore National Memorial, Crazy Horse Memorial, Wind Cave National Park, Jewel Cave National Monument, Badlands National Park, and the wonderful Custer State Park, South Dakota.
On the business side, I have added password-protected areas for individual clients to view pending orders and requested focused photo catalog previews for easier item selection. I have added a similar feature for commercial clients who want to view specific photos and other products. This area is also password-protected for each commercial client. I am hopeful that these customized folders will help you more efficiently select items that will best meet your specific needs. Both areas allow direct electronic communication to answer your questions and expedite your orders.
Finally, while I have been delinquent in posting to this blog, I have been more diligent in posting to Facebook. (https://www.facebook.com/NaturalPhotographyJackson) While the Facebook page is more intended for fun and frequent updates on activities, some of the Facebook photos are also available for view or purchase on the website. If you have a specific interest in any of the Facebook photos, they can be made available in a full-size, high-resolution format for any of the products listed on this site.
I hope you are able to get away this summer and enjoy nature close-up in your favorite location but if your travels are limited you can always vicariously join our travel on this site or Facebook. Have a GREAT summer and thanks for visiting Natural Photography.
OK, I'll admit that I have been remiss in updating the blog recently but I have had a truly amazing two weeks. It started last week in Yellowstone National Park as a simple visit to the Lamar Valley. Sounds easy from Jackson, well, it is in the summer season but when the south entrance is closed, it means a drive south and west into Idaho, then a long but beautiful drive north through West Yellowstone, Montana then along the Gallatin River up to Bozeman. From Bozeman it is back east to Livingston and then south to Gardiner and the north entrance to the park. It was a nice, warm spring day and there were lots of animals - elk, mule deer, big horn sheep, and even some pronghorn antelope.
We drove a couple of hours through the park from Mammoth Hot Springs to the Lamar Valley and on to the northeast entrance and Cooke City for the night. The next morning we found the carcass. A young bison had fallen through the ice in December in the Blacktail Ponds area. It died, froze, and was covered with snow. The day before we arrived a large boar grizzly bear had come out of hibernation a bit hungry and 4-month old submerged bison sound like just the thing. He pulled the carcass partially out of the water and he and dozens of other birds and animals made a very interesting 4 days of photography.
During daylight hours the carcass was visited by bald and golden eagles, dozens of ravens, and several coyote. At dusk and into the night, the grizzly returned with as many as two others. When the grizzlies left, the wolves arrived. It was well after dark so photography was out but the viewing was very good. Coyotes crying in the night added to the drama and the same scenario played in reverse order each morning. The close proximity of the carcass to the road resulted in dozens of posts to The Spotting Scope and other web sites.
The drive back home around the west side of the park was another adventure with a full spring blizzard and white-out conditions. A double tanker truck jack-knifed and rolled over and driving conditions near West Yellowstone were miserable. Teton Pass back to Jackson was clear and the remainder of the drive was uneventful.
How could you possible top that adventure? Well, beloved grizzly sow 610 and her three two-year old cubs came out of hibernation in Grand Teton National Park. She was spotted on Monday and a storm of photographers and observers arrived for the rest of the week. The clan put on a great show every day with a backdrop of Trumpeter Swans, white pelicans, Canada geese, beaver, river otter, muskrat, coyote, bald eagles, and other waterfowl. We visited on Wednesday to watch their migration from Pacific Creek up to Ox Bow Bend on the Snake River. It was a comedy of foraging for frozen fish in the river to random cub wrestling matches as they dug in the snow and ice along two miles of river. They were clearly un-bothered by the 10-20 photographers and visitors as they made their way along the large island at Ox Bow.
On Friday we returned to Ox Bow Bend about 35 minutes from our Jackson home to watch the family again. On the day we missed, 610 had helped the cubs retrieve a frozen beaver carcass from the ice and on this day the family was content to spend the morning in the woods on the island. We photographed beaver and waterfowl and were about ready to pack up the gear when a large boar grizzly appeared on the ice at the south end of the island. He was being harassed by a very brazen coyote but finally sent the coyote packing and took off at a full run through deep snow and dense willows toward 610 and her cubs. 610 continued to prove what a great mother she was, leading the cubs into the woods and across the wind as the boar charged on only about 50-100 yards from them. The boar was distracted by the scent where the cubs had been wrestling in the woods and perhaps by the consumed beaver carcass while the family ran through the woods and emerged again at the south end of the island. 610 sent her cubs across the frozen river to the mainland while she stood ready to defend them from the aggressive boar. Once the cubs were safely on the mainland and downwind from the boar, she crossed the ice and led them back toward Pacific Creek. It was an amazing display of predator behavior and a mother's protective instincts. Some of the photos are posted on my Facebook page:
The national parks are coming alive! Thanks for visiting.
Wyoming? I often get asked why in the world did you move from Florida to Wyoming?
The reason is pretty obvious when you take a look at my last Friday. I started the morning with the drive to take sunrise photographs in the Grand Teton National Park about 15 minutes north of my home in Jackson. After a few shots I decided to return to Jackson and have breakfast at my favorite restaurant. On the way back to town I noticed the the elk herd at the National Elk Reserve had started to migrate north toward their summer home in Yellowstone National Park. About 100-200 elk had crossed the Gros Ventre river and many of the 5,000+ elk remaining in the reserve were headed towards the river. I sped home grabbed some more gear and had a quick breakfast at Bubba's.
After breakfast, we decided to return to the Kelly road to observe the migration of Elk crossing the Gros Ventre. I grabbed my 7D and a 100-400 mm zoom and walked a quarter mile across hard pack snow into the woods. I hadn't walked 100 yards in the trees when I practically ran into four moose. Three of these were very close in the trees and occupied about 45 minutes of shooting time. I kept walking through hard packed snow to the Gros Ventre. Here I was treated to a spectacle unlike any other. About 100-200 elk had already crossed the river and were grazing in the tree line. The snow was completely covered with elk tracks and other signs of the moving herd. I turned to the West and walked along the river looking for the massive herd to follow. During my walk I was greeted by three bald eagles swooping down the river looking for fish. At the first bend in the river a flock of Canada Geese were chattering noisily along the rocky bank. This deserved another couple dozen photos.
I continued along the river and to my amazement on the high banks on the South side there were literally hundreds if not a couple thousand elk who had moved from the refuge to the high bluffs of the river. I remained there for about an hour watching the elk but they had laid down and it was clear they would not be moving in the next couple of hours. As I walked along the river I estimated that there were elk for about 2 miles positioned nearly nose-to-tail along the entire ridge line.
On the way back to my Jeep I stopped again the photograph a cow and two moose yearlings. They posed majestically in a cranny between two trees, seemingly unbothered by my presence. I continued my walk through the woods and was startled by another cow elk as she ran across my path. Over the two hours of my trek, the warm sun had softened the crust on the top of the snow making the walk across the meadow "interesting." I consistently broke through between six and 12 inches of snow as I crossed the meadow to the steeply inclined gravelly bank back up to the parking area on Gros Vente Road.
Before returning to Jackson, I drove down the road past the small town of Kelly seeing three more bald eagles and several more moose bringing the total moose for the day up to 19.
Why do I like Wyoming? This was just another spring morning and a very good Friday.
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.