Articles for August 2015

Photography Perfected

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Contax 139 SLR camera
Contax 139

Our photography consultant writes:

This is the ubiquitous 35mm SLR, the single-lens reflex camera, the design you’re most likely to have actually seen and touched. (The Contax of the picture is a lesser-known name, but still recognizable as the same type as millions of Nikons, Yashikas, Pentaxes, etc.) With its many variations it dominated photography from the 1960s to the end of the film era. In fact, one can argue that the current master of the field is only a modification of this type, as its name implies: digital single-lens reflex, DSLR.

One could also argue that for overall flexibility, ease of use and quality of results the SLR has never really been surpassed and that (as far as such a thing is possible) in this design we see photography perfected. Of course pictures are made by photographers, the camera being only a tool, but after its invention more professional photographers chose this kind than any other.

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A Textbook Case

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textbook and calculationsOur astronomer writes:

Now and then I come across an interview of some Nobel prize-winning (or otherwise distinguished) scientist with the inevitable question, “What got you started on your path to fame?” Almost always it was an inspiring teacher or mentor, a person who imparted a love of or excitement in doing science. Somewhere in the years between High School and Grad School, between the time when our differences were mostly potential and the time we’re on our way in a particular direction, someone lit a fire. Often there’s a quote something like, “He/She showed me that [insert science here] is more than just a set of results in a dusty textbook, but something that I really enjoyed doing.”

Similarly, in accounts of some part of the history of science it’s almost inevitable that I encounter a sentence like, “so science proceeds in sometimes a roundabout and uncertain fashion, not at all as the textbooks tell you.” Textbooks are not often held up as good examples.

The message, sometimes explicit but often implied, is that our job as teachers and scientists is to inspire and excite. Trying to impart “textbook results” is deprecated. Well, this time I am standing up for the textbook and the type of learning it represents. There is a time when it is just what we should be teaching. We need to ask the question: what are we trying to do? What is the outcome we want in our students?

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The Fashionable Twin

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Our photography correspondent writes:

Rolleiflex TLR camera
Rolleiflex 3.5T

This time I’m singling out a type of camera that, while instantly recognizable and quite common in the days of film, was never ubiquitous. Most people preferred other kinds. But those who used them were very firmly attached to them and had definitely chosen them over whatever else might be on the market. This type found a particular home, among professional photographers, with those who specialized in portraits and fashion shoots.

This design is called the twin-lens reflex (TLR if you’re advertising to sell or buy one in the cost-per-word section of the photo magazine). “Reflex,” when used about cameras, means that there’s a mirror involved somewhere. “Twin lens” is obviously appropriate. But why twin lenses? It’s not a stereo or a panorama camera, a kind that takes two pictures at once. Well, the short answer is you need one lens to keep an eye on what the other is doing.

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How can you tell, if you’re not an expert? (2)

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How far can you trust a scientist?

 

Astronomy book and page of equationsOur chief consultant writes: It’s time to take up the question again of how a non-expert can evaluate an expert. In a previous post I introduced paradoxers, people from outside the field who claim to have made some highly important advance. Paradoxers are interesting in several ways and we’ll return to them later. Today we consider the case of some undoubted expert, a renowned or at least established scientist, describing something in his or her field. How much of it can you rely on to be true? How far can you actually trust a scientist?

This subversive-looking question occurred to our astronomer a while back. To try to answer it, he looked into the specific case of astronomy over the period 1833-1944, and wound up writing a well-regarded book with his conclusions. It’s 300 pages long, so I’m not going to try to include the whole thing in this post. His depressing conclusion is that even the best and most conscientious scientists may make statements as known fact, that turn out later to be wrong. His encouraging conclusion is that this is very rare, and for almost all scientists almost all the time, their presentations are reliable. In addition, there are a number of clues that help indicate the reliability, or otherwise, of what you’re being told.

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