WARNING: Part rant and all technical. If you simply enjoy taking photos without being a techno gearhead feel free to ignore this post. I promise to return to more readable posts after getting this out of my system.
On Facebook the other day one of my non-person friends (BorrowLenses) posted a link to a video about T stops vs f stops. Huh? I've been photographing for 57 years and never heard of T stops. I watched it and did a bit of further research. It seems some folks with lots of time on their hands (time that would have been better spent taking pictures IMO) compared the actual amount of light coming through a variety of lenses and learned that (allegedly) your lenses are lying to you. According to them f/2.8, for example, may actually be f/2.9 or even f/3.something depending on the lens. They are (accurately) surmising that some light is lost inside the lens, absorbed by the lens elements, reflection for lens surfaces, etc., which isn't being accounted for with the result that they believe the f/stops are mislabeled.
The only "mis" going on is a misunderstanding of what the f/# means. To arrive at the f/# the diameter of the diaphragm opening is divided into the distance between the lens when focused at infinity AKA the Focal Length (more on that later). The resulting number is the f/#, period, end of calculation. Thus a lens rated at f/2 has a diaphragm opening the is one half the focal length of the lens, an f/4 stop is one quarter the focal length. It's a simple ratio. The diameter of the opening:focal length with the focal length always being "1". It is not and never was a direct measure of the transitivity of the glass although it is a useful approximation for calculating exposure.
So why don't lens manufacturers measure the light each lens transmits? I'm not a lens engineer but I've been a practicing photographer for a looong time so here's my educated hard knocks school answer. They don't because light loss in the lens is only one factor in how much light will actually hit the film/sensor at any given f/stop. The nominal focal length of all lenses is the distance between the lens and the film/sensor plane when focused at infinity. That is the closest the lens can be to the film plane and have anything in focus. As you focus on anything closer than infinity you are moving the lens further from the film plane. You reach a 1:1 subject size to image size when your lens is smack in the middle between the subject and the film.
Yes, I know you can bend the light rays using a +diopter effect (basically a magnifying glass) and the distances won't exactly equal at 1:1 but that's not the point. The point is that as you move the lens further from the film plane the light on the film/sensor decreases because of the law of inverse squares. On an SLR (digital or otherwise) the diaphragm opening can be linked with the focusing helical to approximate the same amount of light to a point. The barrel of the lens however limits how far the diaphragm can open. That's why the maximum aperture on most zoom lenses is marked as variable. When you zoom out, the lens barrel isn't big enough to accommodate the larger opening of the diaphragm at the longer focal length. It's the same size as at the shorter focal length but because it is a ratio of the two measurements, iris diameter:focal length, that same diameter is a smaller portion of the focal length. And yes, it does mean you get less light at any given spot on the focal plane, again because of the law of inverse squares (spread a given intensity of light over a large area and the light on any given part of the surface is less in inverse proportion to the increased distance). Although the effect is minor at subject distances closer to infinity, the light fall off increases as you focus on closer subjects and the progression of fall off is geometric.
There are other things that reduce the light at any given f/stop, notably filters. Before Photoshop allowed you to alter the relationship between values it was necessary to add a filter to the front of your lens. Obviously any filter you place in the light path will reduce the light reaching the film/sensor but that does not alter the ratio of the iris opening to the focal length of the lens. It is something the knowledgeable photographer has to compensate for to get accurate exposure. Or I should say had to compensate for.
All we are concerned about is correct exposure which is a mix of intensity of light and time. Modern cameras all have built in light meters coupled to computer chips to read the light actually falling on the sensor. The meter measures the light directly through the lens and doesn't give rat's patootie what the labeled f/stop is. If your camera has a histogram it tells you whether the light falls within the dynamic range that the sensor can interpret into a JPG based on the chosen exposure program (if you are shooting RAW the sensor will record a somewhat broader range that you can play with later). Even if the f/stop was intended to be a measure of actual light striking the sensor, which it isn't, there is no way the manufacturer could label the diaphragm ring on your lens with T numbers that accurately reflected the intensity since it is variable due to all sorts of adjustments to focus, filtration, etc. that change with each and every image you shoot. A simple ratio of diaphragm diameter to nominal focal length, that is something they can label and that is all it is. So f/4 is f/4 no matter what other circumstances are reducing the light coming through the lens and no, the manufacturers aren't cheating to make you think the lens is faster than it actually is. Today's photographers have marvelously technological cameras that virtually eliminate the complex calculations needed to get accurate exposure 50 years ago. Be grateful, stop wasting time on silliness and go take pictures. Jeesh!
Wednesday, November 12, 2014
Friday, November 07, 2014
Over a month and no posts. I've been wrestling with my thoughts on the state of photography, in particular, my photography. Looking at what's on the web I feel kind of 'out of step' but at the same time I have no desire to be 'in step'.
I just finished reading Disappearing Witness: Change in Twentieth-Century American Photography by Gretchen Garner. It is an art history book which is not my usual reading matter. I read enough art history in college to last me for a lifetime. Art history is mostly dry boring stuff and there is a certain amount of that in this volume, recitation of lists of photographers and how they fit into this or that genre. But this volume attracted my attention because its premise is something I had noticed myself.
One aspect of aging, of having been around for a long time, is that you gain a perspective that younger people don't have. In a sense it's like you learned to drive at night, able to see only what your headlights could illuminate and gradually the sun comes up and then you can see all this stuff that was hidden in the darkness. The stuff immediately around you, which was all you could see in the dark, takes on a whole new context once the sun comes up. I learned and began my practice of photography in the latter end of what Ms. Garner refers to as the "witness" mode of photography, the practice of looking out at the world, connecting with it on a psychic and emotional level, and making images that attempt to convey that connection to the viewer. That largely remains my mode of expression to this day.
Somewhere in the sixties or seventies the focus of art photographers took a major turn inward. It manifested in photographs that were less about the subject in front of the camera and more about the inner life of the photographer. Images became staged performances that were recorded on film and later digitally to illustrate an idea the photographer had. Such photographs had existed for some time previously of course but most were commercial illustrations for advertising or magazines, images made by photographers under the direction of art directors or editors. In the latter '70s and onward however it because the major trend of fine art photography.
I have observed this trend even among photography enthusiasts who don't aspire to "fine art" status but are moving in this direction as well. I don't know if it is the influence of Photoshop with its infinite control or a response the art world but I see ever more constructed as opposed to observed images as time goes on, images that are less about the subject matter and more about the photographer.
Perhaps I'm just being "stuck" in my past but I'm not sure that this trend is a good thing. Yes, we need to look inward, Eastern religions with their emphasis on meditation have been doing this for millennia but always as a ground for relating outward to the rest of creation or seeing ourselves in what we see. It is my belief that is what "witness" photographers were trying to do. Whatever the trend my photography will continue to look outward, to engage the larger world.
The photo is of a tree on the corner of Rt 56 and Garfield Rd outside Potsdam, NY. It caught my eye as I was driving into town one day and I stopped to photograph it with my cell phone which was the "best" camera (the one I had with me). It has been modified in Photoshop to accentuate the mood.
Sunday, September 28, 2014
As long time readers know I adopt an Adirondack lean-to at Scott Clearing. The reason it is a clearing is that back in 1880s there was a lumbering camp in this area, some evidence of which remains to this day. The photo above is from the site of the pond onto which the logs were piled for release downstream in the spring. The bright area below the center red tree is the opening in the old dam (seen close up below). The dam was originally about 12 feet high.
I hope you enjoy the photos as much as I enjoyed the day. If you wish to share them with others respect my copyright and send them the URL to this page. Don not repost elsewhere without permission.
Saturday, September 20, 2014
My favorite filters are the Topaz set. I started buying them when Fo2Pix folded and the BUZZ 3 filters were no longer available. Topaz picked up the gauntlet and created a similar filter in their Simplifier filter. They went on to create a number of other useful filters which I use frequently but the Simplifier filter remains my favorite of the bunch.
What it does is average the tone and hue of groups of pixels so that you get patches of color and tone. How big the patches are, what range of tone/hue is averaged, is adjustable with a slider control. With the original BUZZ 3 filter that control went so far that you could end up with a rectangle of one solid color. Topaz Simplifier doesn't have that range of control but who really wants to reduce their images to a single tone & hue anyway. Simplifier goes farther than I'm likely to ever want it to.
Today's photos all use (moderately) Topaz Simplifier in honor of two things. First, two of my images are in the 2015 Fine Arts Up North calendar. Both images made use of the Simplifier filter (along with other digital modifications). You can buy a copy of the calendar by contacting the Arts Council at this link. I don't get anything from sales but it supports our arts community.
The second reason for today's all Simplifier collection is that this was the last day of the Plein Air Festival in Potsdam. I'm not a painter (in recent years at least) but I went out in search of subject matter in the local community rather than running off to the mountains as I usually do and most of the subjects I found seemed best suited to this treatment which many people tell me makes the images look like paintings. Indeed massing tone and hue is exactly what painters do.
I went to three parks in Potsdam, Lehman Park, Ives Park and the small one on Fall Island. Afterward I drove to Canton to visit Heritage Park which I hadn't visited before. The photo above is from the parking area at Heritage Park and is my favorite of the day. The one below is from Lehman Park.
The next was made in Ives Park. The wind gusts were quite strong and I wanted to capture the blowing leaves of a large willow on the bank of the Racquette River.
Then come two wildflower photos from the Fall Island park, a Thistle and a Black Eyed Susan.
Finally a photo of some Plantation Lilies by the foundation of the church on Fall Island. This is a repeat subject from many, many years ago. I originally photographed it on the 1st roll of film I shot in a used Fuji GX 645 folding camera. That was a great little camera that produced amazing negatives.
If you click directly on an image you will get a larger view. I took more photos but this mix represents all the sites I visited. I hope you enjoy seeing them and please remember that they are copyrighted. As always, if you want to share them with others, give your friends the URL to this page, Do not repost them elsewhere without my express permission.
Saturday, August 02, 2014
This past winter I bought a Petzval lens reproduction from Lomography through a crowdsource project they ran. There were some delays and when the lens came it came minus several of the bonuses Lomography promised. Two of the missing bonuses were of no consequence to me (a camera strap and a canvas bag) but I also did not receive the special shape Waterhouse Stop set that was promised and that I did care about. Despite writing to Lomography, both through the crowdsource site and directly however have produced no result. I still do not have the promised special shaped stops. I would think twice before dealing with Lomography again.
The lens is well made with a nice brass finish, modified from the original design to fit directly on modern Canon or Nikon cameras (mine is the Canon version) and produces images with pleasant depth of field as well as fall off of sharpness toward the corners which gives a vintage look to the images. It is quite sharp in the center and overall sharpness increases with smaller stops since you are only using the center of the lens. Operation is strictly manual. The Waterhouse Stops simply drop into a slot in the lens barrel. Since the opening is perfectly round, unlike a variable diaphragm which works on movable leaves, the out of focus areas are pleasantly blurred. The camera controls the shutter speed and focusing is achieved via a rack and pinion on the bottom of the lens. The lens was promoted as a portrait lens and it is undoubtedly good for that but I bought it primarily to use for flower photos. Photographing individual or small groups or flowers shares a lot in common with portraiture as this group of images demonstrates
I wish the Waterhouse Stops fit a touch more snuggly or had some mechanism to hold them in place other than just gravity. Working in the field I'm concerned about dropping and losing one of them. I've tried using a hair band to hold the stop in the slot when I turn the camera on its side but I'm not entirely happy with that solution. Also the suede case Lomography provided for the lens and set of stops is virtually useless. It is awkward to get the lens into the case which is a poor fit. The case is a flat rectangle that opens via an overlap down the middle of one side and the stops are simply put into a pocket on the inside of the case. I can see that I will have to make my own case for the stops, something with slots for each stop rather than dumping them together in one too large pocket. I'd prefer that they be sorted by f/stop for ease of selection. I'll probably end up buying a Neoprene pouch, a round one, like the lens, to store the lens in.
This group was shot in the field behind my house, Spotted Knapweed above and below are two images of Yellow Daisies, a cluster of Butter and Eggs, a Rough Fruited Cinquefoil and a Plantation Lily that is in one of our flower beds. I converted the last to B&W because I thought that suited it best.
Saturday, July 05, 2014
I went to Saranac Lake last night to watch/photograph the 4th of July freworks. I've only tried shooting fireworks once before about a decade ago so for this effort I was still in the learning/experimental mode. I shot them at around f/8 on manual mode. The shutter speed varied from 1 sec. to 2½ sec. I had the camera on my tripod and was shooting mostly at the wide end of my 18-135mm zoom because I wasn't sure where the bursts would occur relative to the frame. I didn't look through the viewfinder. I just watched the sky, listened to the sound of the rockets and pressed the shutter release at the point I thought they were about to burst. They all have post exposure adjustments in Lightroom 5; cropping, some curves, highlight control, clarity and saturation. It was kind of fun. I might try it again sometime. More photos below, the most I've ever posted at once. Please respect my copyright and share by referring others to this page. Do not repost elsewhere without my express permission.
The one below reminds me of some old rock album covers.
An interesting abstract.
A new galaxy?
Tuesday, June 24, 2014
Late this morning I drove down to Paul Smiths and delivered my entries for their annual 'Life on the Lakes' juried show. After getting a lunch in Saranac Lake I headed home but when I got back to Paul Smiths the rain had stopped so I took my camera on the Boreal Life Trail to see what I could find. My first find was the Bog Laurel above but there was lots more.
The Pitcher Plants are all lower than the boardwalk that is the trail across the bog. That had me lying on my belly with the tripod hanging over the side for most of the above shots. The Bunchberry and Dog Bane below were at a more comfortable height.
All the photos are copyrighted. Please respect my work and do not repost without permission.
Monday, June 16, 2014
A couple of friends and I hiked to "my" lean-to (I am the adopter of Scott Clearing lean-to) on Saturday to do a semi-annual cleanup and check for needed repairs. The streams were all running high from the heavy rains that had fallen the day and night before. On the way back out we stopped by Rocky Falls and I made the above 3 frame panorama.
When I posted it to Facebook one person thanked me for bringing the scenery into her home and that is part of why I photograph but only part. I know some wilderness photographers who make their photos as a way to encourage preservation of wilderness and Ansel Adams' photographs have been credited with convincing congress to preserve some western parks but Ansel was also a prolific advocate of wilderness. He wrote letters almost daily and was very active in the Sierra Club. While the photos played a role, they were secondary to his activism IMO. I belong to the Adirondack Mountain Club but mostly as a low key member. I participate in the lean-to adopter program and I donate use of my photos but I don't kid myself that my photographs are going to play a significant role in preservation of the park.
So why do I do it? Mostly for myself. Photography is a way for me to connect with the landscape more deeply than just hiking through. It makes me think about what attracts my attention and how best to represent that in an image. There is also the discipline of observation that goes along with photography. That discipline makes me a more keen observer of my surroundings. Practicing any visual art medium can develop your observation skills but photography appeals to me the most.
The photographs aren't entirely for me alone of course. The process is for me but once I have made an image I think is successful I like to share it and while people may enjoy seeing them I hope they will also be inspired to go out and spend time in nature themselves. The very best photographs I (or anyone) can make are pale imitations of the experience of being there. If anything is going to convert a person to being a preservationist it is the experience of being in the midst of nature and realizing that we are a part of nature that will achieve the conversion, not my photographs. At best the photograph inspires them to wander off into the wild to see what's there and be open to what wilderness has to offer.
The photograph below was made along the trail on the left bank of the brook as we were going back to the main trail after visiting the falls. After looking them up on the web I find that white Moccasin Flowers are not uncommon but this was the first one I'd ever seen so I felt it deserved a portrait.
Friday, June 13, 2014
A review (sort of) that is photography related (again, sort of) but not about photography. After getting a Kindle Fire I decided to try subscribing to a couple of digital magazines, National Geographic and Outdoor Photographer. Both feature very nice photographs and it seems a shame to throw away/recycle print copies after reading them but what do you do with them? Enter digital subscriptions.
I really like the National Geographic digital presentation. They reformat the articles for digital presentation, text is separated and scrolls vertically, moving from section to section is done with horizontal scrolls. Photos are organized in albums for viewing with only captions. They even include interactive maps and audio/video clips. Very cool stuff, very well done, it takes good advantage of the touch screen. I haven't done a side-by-side check of the digital version against the print version but I think the articles are condensed from the print version. They don't seem as long as I remember from when I had a print subscription in the past but they are long enough to convey the stories. I don't finish one wishing they had included more and I read almost all of them. The one niggle I have is their app/delivery system. Perhaps the digital format they have chosen dictates it but I have to guess when an issue is available, open the app, log in and manually download the new issues. Maybe if they sent an automated email to let me know when a new issue was available it would annoy me less but aside from checking, there seems to be no way to know for sure when the latest issue is available. Never the less I give them 4½ stars out of 5 for the great presentation of great content.
Outdoor Photographer got the delivery right. When a new issue comes out it automatically downloads to my Kindle and pops up - BAM! as Emeril would say. No effort on my part. That's the last cool thing about the digital version of Outdoor Photographer. All they do is digitize the print version as whole pages, like a pdf file. Perhaps that would work fine on a desktop computer with a large screen but on a Kindle sized tablet it is a navigation nightmare. If you view the whole page, the print is far to small to read. If you enlarge it enough to be legible you are looking at only a section of page and spend all your time scrolling both sideways and up/down trying to read it. And because OP has a nasty habit of spanning photos across pages you see only a portion of the photo at a time or turn the Kindle sideways for a full two page view which is very small. Consequently I find myself reading very little of OP, a quick scan of each issue and perhaps one article, that's it. Add this to the editor's apparent notion that the only good landscapes are west of Denver (an annoyance I've noted in the past) and I will pass on renewing that subscription.
I've tried other digital subscriptions (news media) and noticed the same issue. They either scan and dump the print version as whole pages, sometimes in a proprietary format like Zinio, or they reformat the content to fit the constraints & advantages of digital presentation. IMO the latter is superior and the former is a poor substitute for print which isn't dead yet and won't be until publishers wise up to the differences or perhaps those who don't will simply cease publishing altogether.
The photo above has nothing to do with the post. It is just there for your viewing pleasure. It is from the canoe trip in the prior post. Like the others it was made from the canoe. Please respect my copyright and do not repost either the photos or the text without permission. Share by referring to this URL of this page.
Thursday, June 05, 2014
There was some headwind as I set out but it was less strong, or so I thought as I had less trouble paddling into it. Church Pond is somewhat smaller than Mountain Pond but is linked to Little Osgood Pond by a canal that was dug by Paul Smith. There is another canal from Little Osgood to Osgood Pond which by some standards could be called a lake. I have never understood the pond vs lake naming in the Adirondacks. It is so capricious that it must have been a matter of whim by the person naming the body of water. It does not seem to bear any relationship to relative size.
The stump above is along the shore of Church Pond on the side toward St John's of the Wilderness (http://jims-ramblings.blogspot.com/2009/08/st-johns-of-wilderness.html). It was the new evergreen growing on the side of the stump that first caught my eye. Upon closer inspection I decided to include the whole stump and surroundings. I especially liked the reflections on the ripples in the water. The image was converted to B&W in Lightroom based on a preset that I created. I tend to tweak all presets taking into account the individual image and this was no exception.
After paddling the length of Church Pond I came to the canal where I found a second interesting stump. Photographing this one was a challenge from the canoe. The canal is completely under the shade of the surrounding trees and a canoe is not a very stable platform. I managed a sufficiently short shutter speed (exposing for the shadows) by raising the ISO and opening the diaphragm to f/8, helped along undoubtedly by the image stabilization in my Canon 7D. The version above has a modified Lightroom Infrared preset applied to it. I did away with the negative clarity in the preset and added some sharpening, also a touch of burning in on the upper stump.
I wasn't able to navigate the second canal to Osgood from Little Osgood because of blow down across the narrow channel. Perhaps another day. On the return trip I stopped to photograph the lean-to and dock that are adjacent the canal in Church Pond. Again I used the modified LR Infrared preset. Returning to the dock where I had put in I had a tailwind but noticed a distinct current flowing in the opposite direction. That may well account for the relative ease of paddling into the wind when I first set out. It was a good start to a new season of paddling and hiking in the Adirondacks.
All photos and content are copyrighted. If you wish to share with friends, please do so by giving then the URL to see it here.
Monday, May 26, 2014
Recently I watched “The Monuments Men”, a movie that I recommend although this isn’t a review. This is more of a mulling or pondering of the rationale the main characters used for their mission in light of how the world has changed since WWII.
For those who aren’t familiar with the movie the plot (based on real life) involves a group of art specialists who set out to save the art that has been stolen by the Nazis in their advance through Europe. They volunteer to serve in a special unit to find, identify and retrieve great works of art as the Germans retreat after D-Day. The rationale for the mission is that the art represents the culture of the invaded countries and if it is lost or destroyed it will mean the destruction of the culture. As the lead character puts it, people can be killed but new generations will be born and the culture lives on through the art, thus it is important to preserve the art.
As the Germans gathered up the art in their retreat they stored it in mines and it takes the protagonists some time to learn where it is. The rest of the army is too busy fighting to provide more than minimal assistance and pays little attention when the Monuments Men do succeed. The only discovery they make that gets attention is a cache of gold in one of the mines. That gets everyone’s attention including the media. Over the course of their self assigned mission the Monuments Men save and return millions of pieces of art, paintings, sculpture, etc. In the process they lost two of their unit plus two members of the team from allied forces. In the final scenes, Frank Stokes, the leader of the unit is reviewing the mission for his superiors and is asked “Was it worth it?”. He responds that it was.
After the movie I wondered about his premise in terms of the modern world. In prewar Europe I can see where it could be argued that the art and architecture was the embodiment of the culture in which it existed. In today’s global society I’m not sure that still applies. Yes, there are remnants of that old culture but it is rapidly fading and art is more an expression of the individual artist than of the culture and values of the society in which the artist works. Would any art curator today risk life and limb to salvage Damien Hirst’s pickled shark on the pretext that it represented our culture? Or how about Raffaello D’Andrea’s robotic chair? I wonder.
Tuesday, May 20, 2014
It's been a while (last fall) since I've been down to the Adirondacks to do some photography. Sunday I drove to Old Forge to take in the last day of Paddlefest. The event was disappointing on two counts. One, the weather was distinctly chilly. There were only a handful of people brave enough to try out the paddle boards and boats. Second, there were even fewer canoes than last year. The vast majority of craft were standup paddle boards and every sort of kayak you can imagine. The guys from Slipstream Watercraft had their superlight canoes there (as little as 9½#). Those were interesting but not suitable for my uses.
I did a bit of photography along the way. The waterfall above is right alongside Rt 28. The stream comes out of a large culvert a bit up stream and then runs parallel to the highway for a bit. There is a bit of guardrail in the picture at the very top. I probably shouldn't confess that. I should just let you all think I hiked several miles to reach this place. I will be doing that later this summer (hiking) but not on this trip.
I also drove down to Thendara to check out the RR station there. I was last there when they were just gathering old RR cars to restore. I made some photos of the station, which is architecturally interesting, and a box car that was there.
Enjoy. If you wish to share with your friends, please refer them to this page. Respect my copyright and do not repost.