Why are three cameras hanging from my neck?

Last Sunday I went on one of our monthly flickr walks--this time to the Allen Centenenial Gardens on the UW campus. It's a public garden that for some reason had failed to register in this photographer's brain cells. Not only had I never photographed there, until recently I didn't know the garden existed.

We flickr-walkers weren't the only ones with cameras. It's that sort of place. So after I had stepped away from the group to take a series of reflected images, I returned to the group to find ones of the orher flickrwalkers explaining to a non flickrwalker what she would need to take macro flower photos.

In rough order of expense, she would have to buy at least one:
1--set of closeup lenses
2--set of extension tubes
3--macro prime lens
4--macro zoom lens.

A mini tutorial, well explained--but with one unspoken and wide spread assumption. After you paid all those big bucks for your DSLR the rules demand that you use it to take all your pictures. Big bucks > better camera> photographic masterpieces. Right??

Not necessarily, or so I believe. When I joined the conversation, I lifted the Canon S3IS that was hanging around my neck, and added a fifth option. She could buy a highish end Canon non-DSLR like mine. Then, after she downloaded the totally free CHDK firmware extension she would have all the goodies like RAW mode that the Canon marketing folks stripped out of their non-DSLRs. Plus a whole pile of extra goodies like scripts that the Canon engineering folks never managed to invent.

The best of all worlds and for only a fraction of the price of a macro lens. Or as it turned out, totally free. Her boyfriend owned an S3IS that was gathering dust somewhere.

A wild unusual idea, I know. Carrying more than one camera around your neck. So wild and unusual I was asked to pose for a series of photos of my three cameras to document the concept.

OK, what is going on here. One of the holdovers from 35 mm film days is that 24 mm lens is a wide angle lens, a 50 mm lens is a normal lens (whatever that means) and a 200 mm lens is a telephoto lens. Correct if you are shooting 35mm format. Wrong if your sensor dimensions are not 35mm by something less mm.

Since the vast majority of digital cameras use a smaller sensors we now have the "35 mm equivalent" spec. By the way this is not a new invention of the digital age. With larger and smaller film formats the focal lengths are also different.

Very different, for instance, if you are shooting with a 8 by 10 inch view camera. If you study the history of photography, you would be very hard pressed to come up with any 19th century telephoto images. Except for a few images of the moon shot through astronomical telescopes long enough lens weren't available.

And to jump off topic for a moment, why is 8 by 10 inches such a common print format. First reason--in the 19th century you could only make contact prints and 8 by 10 inches makes for a very viewable size. Second reason, you could wander in to the local general store and buy your glass plates--8 by 10 inches was also the standard window pane of the time.

Which brings up an interest question--how many masterpiece of photograph were lost when some frugal farmer scrapped off the emulsions of a stack of worthless glass negative to repair his greenhouse after a hailstorm. A common practice in years gone by.

But back to the point of this blog (Yes there is one)

Instead of talking about "35 mm equivalents' we could talk about fields of View, Like how wide an angle the photo will take in using a a 1/2.5 (5.75 X 4.31mm) sensor-- which happens to be the sensor size on my S3IS. Then we would easily see (with the help of a little geometry) that the 6 to 72 mm zoom lens of the S3IS had a field of view that ranges from from ~62 degrees to ~4 degrees. If you insist on doing it the old way, the chart--found in a garage sale book-- shows that 35 mm eqivs range from 36 mm to 432 mm.

So what! Little cameras have little sensors and little lens and don't cost much. DSLR have big sensors that cost lots and lots more but they are always better because_______!

Nope and DOUBLE NOPE!

Short focal length lens have a much greater longitudinal Depth of Field (DOF). That's optics talk for saying that more of the flower or bug you pointed your camera point at is now in focus. Many of the so called Internet gurus will tell you different but optics is optics and the shorter the focal length the greater the DOF.


















So there, all you DLSR-with-zoom-lens lovers!!! My S3IS with a 6mm super macro mode will always have a greater DOF. Ain't just cheaper. It is always--well sometimes always--better.

Here's proof for the doubters.

The top image was taken with a new 90 mm Tamron zoom at f8 in my local camera store . From top to bottom the artificial flower is about 1 inch tall















And this image was taken with my S3IS, again at f8.
















To quote the friendly salesman after I showed him the two images. "Looks like you just saved yourself five hundred and fifty bucks."

And to show how the S3IS works in the field. The flower was about 3/4 inch in diameter. The love bugs--they were too busy and preoccupied to be measured




















Macros are fun. So expect more posts about them.

You have been WARNED !

Glaciers, moraines and global warming

Yesterday, on a hot, hot, humid, humid, heat stroke warnings on TV afternoon I walked down the steep slope of the Elver Park moraine to the algae covered kettle pond at the moraine's bottom. For once I had the park almost to myself. Normally the bike path and wooded trial that start at the back parking lot have their share--and more--of bikers and runners this late in the afternoon. But today--except for one hardcore and heat impervious biker--I saw no one. Global warming had engulfed Madison.

Nine to ten thousand years ago the scene would have been different. The moraine marks the farthest push of the last of the glaciers that have scraped the Midwest flat. From the bottom of the kettle pond--formed when a ten acre glacial ice cube melted and the ground level dropped--to the top of the moraine looked to be about 400 feet. There had been a lot of ice here when mammoths and mastodons and saber tooth cats roamed the frozen tundra to the south.

So what, you might ask. The ice ages are over. Except in cute animated movies.

But the ice ages are NOT over. We are in an interglacial period--a period of warmth when the glaciers retreat north. Once there they begin to recollect snow and ice so they can advance south again. Then they hang around for a couple hundred thousand years.

Happened four times in the last million years. The basic causes of the glaciers--the earth's tilt and orbit, the heat output of the sun, and the routes of the ocean's currents that move or don't move heat from the south to the north--have not changed. So there is no reason to think that it won't happen again.

Quess what. Interglacial periods last an average of ten thousand years. And since the ice was here nine to ten thousand years ago--so it's about time to think of selling your Canadian fishing lodge. We might be in for a long cold snap.

Far fetched. Not really. Starting around 1400 Europe--the only northern area where anyone wrote about the weather--had its Little Ice Age. Glaciers moved down the Alps. Bad weather lead to famine and peasant revolts. Even the Thames river at London froze over solid for several weeks in 1815. Something that hasn't happened since.

Why?

1815, the start of the Industrial Revolution. Ever since then we have been dumping more and more CO2 into the atmosphere, trapping more and more heat from the sun and melting arctic ice at a rate never measured before. The great and evil global warming.

But what would have happened without global warming. Would the Little Ice Age be still with us--long bitterly cold winters, short growing seasons and a frozen Thames almost every year.

A contrarian position, I know. Not at all. political correct. But something to ponder as I sort through the images of moraines and kettle ponds taken on a hot hot day along the Ice Age Trail

Continuing Adventures

While my feelings about Nikon's sales and marketing and how they crippled the D60 haven't changed, I have discovered some work-arounds that make my garage sale lenses useful. But first I'll discuss the optical characteristics of the two lens. They weren't what I expected.

Of the five lens I now own that fit on a Nikon, one of the primes has a 50 mm focal length. Three others can be set to 5o mm or close to it. So an obvious first test is to mount the D60 on a tripod and take a series of pictures with each lens.

My target was the licence plate of my neighbor's car. It was parked about 125 feet from where I set up the tripod and the lines of the numbers and letters were a 1/4 of an inch wide. Resolving the lettering at this distance was reasonably tough challenge for the camera and lenses. My fifth lens--the 35mm prime--couldn't do it

The D60 has three focus boxes. As you can see from the full frame image I shot with the box on the left over the licence plate. Lenses are at their best in the center and I was looking for problems.

A rule of thumb is to close the iris about 2 stops to photograph at the sweet spot. The down side of doing that is you are using only a quarter of the light gathering power of the fast lens you paid good money to buy. A problem? Depends. When it come to camera optics (and ISO setting and Depth of Field and ....) good photography is always a series of compromises.

Why? you may ask. The individual elements (simple lenses) in your lens barrel have their own series of aberrations--spherical, coma and astigmatism--that blurs the focus The idea behind an optical design is that for every lens element that blurs the focus in one direction you add another lens element that blurs it in the other direction. Then you place the iris in the lens barrel where the focus will clean up when you close it. A simple idea in theory; a much more complicated problem in practice. Big buck pro lens can have up to twenty lens elements of varying types.

Even a disposable camera I once bought for $12 and tore apart to modify surprise me with a four element lens. Since all the pieces fell out on the table, putting them back together in the proper order and orientation was a bit of a challenge.

For this test I took a series of five or six photos spaced a stop apart with each lens.

As you can see from the blow ups of the licence plates the f1.8 50 mm prime lens has a problem when it is wide open. The G looks more like an E and the W at the end is a blob.

But as I expected, the plate became readable when I stopped down the lens to f 2.8.

So the prime lens turns out not to be quite the cult classic lens that some on the Internet have claimed.

As for the other three lens. their images were readable at the iris openings I tested.

The big surprise was how sharp the thirty year old Vivitar 35-70 mm zoom was. The lens that I once thought might be only good for parts appears to be the big bargain.

Back in the 1980's Vivitar wasn't noted for high quality amateur optics. The company imported all its lens and, business being business, bought and sold them as cheap as possible. You get what you pay for.

With one exception. After some research I discovered that lenses with magic serial numbers, 28xxxxxxx, were made by Komine. Those folks turned out above average optics. And yup, my serial number is 28213560.

How above average is the lens? One way to work around the rangefinder problem (see the previous blog if I'm confusing you) is to mount the camera on a tripod and switch back and forth between the manual mode where the camera takes a image and the aperture mode where the rangefinder works.

What happened? The macro--or micro as Nikon calls it--photos are below.

At the lens's closest focus distance--15 inches-the long dimension of the area imaged is 110 mm. This works out to a 3:1 subject to image ratio using the full frame and old fashion 35 mm rules. Not the 1:1 ratio purists insist on ....but have you priced one of those babies?

When shooting studio still lives-- (How did an arrangement of the inanimate end up with that name? Still, yes . Live, no.) Back to the subject at hand. With my non live still lifes I can take longish exposures. The top photo is f2.8 at 1/125 sec. The one below it is f22 at 1/2 sec.

Love the control over the depth of field the lens gives me. It's a couple inches at f22.

What else could I do. Add a #3 closeup lens left over from my film days. That brings the long dimension down to about 70 mm for a subject to image ration of 2:1

And what about the 2X telephoto extender. Now we are down to 35 mm and at the magic 1.1 ratio.

After that success--time for a field trip. Without a tripod

So it's back to focusing basics. The lens has a focusing scale. I have a tape measure. The camera also has a little green dot the lights up solid what the area within the focus box is in focus. Even in manual mode. Nowhere as easy to use as the rangefinder but it's something.

Unfortunately, the dot is part of a servo system that doesn't servo. But if I and the camera are close to the correct distance and I rock back and forth, I can make the dot light up.

Occasionally. If I don't move too fast. And if the photo gods are giggling. I'm going to have to work on that technique.

Plus find a screwdriver that fits the tiny, tiny screw that holds the focusing scale in place. It has worked loose. The only thing holding it anywhere near its right place is the oval 'passed inspection' sticker.

But despite these problems, I did steal some images in my neighbor's flower garden

And since we are using an antique lens, what would be more appropriate that to convert it to black ane white.

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