Saturday, October 29, 2011

The Evolution of the Camera

Long ago when the world was young and cameras used film, there were two kinds. With a viewfinder camera, the human looked through the viewfinder, the camera looked through the lens, and the two views were different—significantly different for close-up shots. A single lens reflex camera (SLR), typically larger and more expensive, contained an elaborate internal mechanism to permit the human to view the scene through the same lens that the camera saw it through. To  take a picture, the mirror that was directing the image up to the prism that bent it to reach the human's eye swung up and out of the way, in order that the light could get to the film instead. (There is also evidence in the fossil record of a still earlier design known as a twin lens reflex).

After digital cameras came along and I started using them, it occurred to me that the image I was seeing on the view screen was the same image that would be recorded on the camera's memory—one of the advantages of using electronics instead of optics for the purpose. I was already looking through the camera's lens, so no need for a mirror and prism. Oddly enough, however, SLR's (called dSLR's since they were now digital) were still being made, were still large and expensive, still had an elaborate apparatus of moving mirror and prism, and were still regarded as what serious photographers used. 

They had two significant advantages over the less expensive sorts of digital cameras—interchangeable lenses and much larger imaging sensors, permitting them to take better pictures. They also had optical viewfinders that let you look through the camera's lens. The resolution perceivable by the human eye is higher than the resolution of a camera's viewscreen, so getting the image directly to the human was worth something—but, given the quality of the available screens, not very much. That, at least, was how I saw it—making the internal mirror and related apparatus the photographic equivalent of the human appendix.

It couldn't last—and, fortunately, didn't. It eventually occurred to someone in the industry that a camera with interchangeable lenses and a large sensor but without mirror, prism, and optical viewfinder could be very nearly as useful as a dSLR but considerably smaller and less expensive. 

My Sony NEX-3 arrived yesterday. It cost about half as much as a comparable dSLR—and has the same sized sensor. With the smaller of its two lenses it is not very much larger than the pocket camera it replaces.


17 Comments:

At 9:12 AM, October 29, 2011, Blogger Jose said...

"The resolution perceivable by the human eye is higher than the resolution of a camera's viewscreen, so getting the image directly to the human was worth something—but, given the quality of the available screens, not very much. That, at least, was how I saw it—making the internal mirror and related apparatus the photographic equivalent of the human appendix."

One would think so, but unfortunately LCD screens are woefully bad in well-lit environments. There are workarounds (wear polarized glasses and it'll help), but generally LCDs are pretty useless for composition in direct sunlight, for example.

(There are some additional differences in shutter control and image processors -- not to mention autofocus control -- between the current mirrorless cameras and dSLRs, though there's no reason these more advanced electronics & mechanics can't be made available in premium mirrorless cameras.)

So, as always, life is a matter of trade-offs.

(BTW, once one carries a couple of good lenses the weight (and cost) of the camera body is pretty irrelevant.)

On the other hand, I keep waiting for Canon to make a mirrorless camera with their lens mount so I can use my dSLR glass with it.

Enjoy your NEX.

Cheers,
JCS

 
At 9:30 AM, October 29, 2011, Anonymous Norm said...

Another reason the viewfinder is not so important is that cropping is so easy in electronic form. I no longer worry about framing a picture the way I did with film. I just click away, even in bright light when I can't see the screen very well, and frame later. Also it is trivial to take multiple exposures, no expense, no need to change film.

 
At 9:54 AM, October 29, 2011, Anonymous A Subset said...

The crucial difference for me is the ability to stop down the lens and actually SEE what depth of field effects you will get. This makes a huge difference in the image, and is something that is rarely addressed in discussions of this topic. For me it's a deal breaker.

But for others this is totally not an issue. I hope you have fun with your new camera. I'm awaiting the arrival on these shores of the new Ricoh GR Digital IV which I want to digitally replace my favorite camera of all time, the Olympus XA, a very small, very good 35mm rangefinder camera of the 70s.

- A Subset

 
At 10:04 AM, October 29, 2011, Anonymous Anonymous said...

That camera came out last year and was discontinued earlier this year. Did you get a good deal?

 
At 10:17 AM, October 29, 2011, Blogger Jose said...

A few things in favor of the mirrorless cameras that are worth considering:

1) The best camera is the one you have on you when something you want to photograph happens. So, anything that makes a camera more likely to always be on you is a positive.

2) I always take photos of my students in the first class (because in the face book we get from administration the students are well-dressed and smiling and therefore nothing like in class). In the years I took the photo with a point-and-shoot, they almost didn't acknowledge. When I pull an SLR, they start composing themselves (and therefore defeating the whole purpose of the photo). This also happens in street photography.

3) Digital Rev TV (on You Tube) has a series in which they give professional photographers cheap cameras; they still get pretty good photos. As Scott Bourne used to say, 98% of cameras are better than 99% of photographers.

Cheers,
JCS

 
At 5:26 PM, October 29, 2011, Anonymous Douglas Knight said...

When are you talking about? In the early days of digital cameras, say, 2005, the worst part about the LCD screen was the delay. They are probably fast enough today. The second biggest problem is the brightness that Jose mentions. The third problem is the resolution, but maybe that only matters if you care about depth of field, as A Subset and I do. Norm is right that the traditional importance of SLRs, precise composition, is obsolete, but I would still like an approximate glass viewfinder.

 
At 7:43 PM, October 29, 2011, Blogger David Friedman said...

Anonymous correctly conjectured that I got a good deal on the (discontinued) NEX-3. Last weekend someone showed me his NEX-5 and told me about the NEX-3. Checking online sources, I discovered that Amazon was selling the NEX-3 with both of the standard lenses (Pancake and 3X telephoto) for significantly less than $500.

Having made up my mind that that was what I wanted, I tried to buy it, only to find that the web page no longer permitted the addition of the second lens to the package. Next time I checked, the price had gone up a bit, to about $500, but the pancake lens was again available as a free addition. I bought it.

The pancake lens hasn't arrived yet, but I expect it shortly.

 
At 11:12 PM, October 29, 2011, Anonymous Andrew said...

These cameras are not any cheaper than DSLRs, you simply bought a model that is a year out of date. Compared to DSLRs with similar features that are a year out of date, the pricing is similar.

You seem to be under the illusion that a flip up mirror and prism/mirror are expensive. They aren't. They're old, cheap, simply tech.

Virtually all DSLRs today also support taking photos using live view on the sensor.

The main disadvantage currently of this type of camera is that high quality lenses are not available, and the lenses available are relatively high in price.

 
At 11:14 PM, October 29, 2011, Blogger Jonathan said...

I'm habituated to putting my eye right up against the viewfinder. Holding the camera some distance in front of me to see the LCD screen must be possible, I suppose, but it would take some getting used to.

 
At 7:27 AM, October 30, 2011, Blogger David Friedman said...

Andrew wrote:

"These cameras are not any cheaper than DSLRs"

I don't think that is correct. It is true that I got a good deal because the NEX-3 has been replaced by the NEX-C3 and the Nex-5. But checking Amazon, the NEX-C3, with the zoom lens, is $599. Checking Sony dSLR's, most of them seem to be significantly more than that--I'm not sure which of the less expensive ones are, like my NEX-3, old models.

 
At 9:38 AM, October 30, 2011, Blogger Studio Hayek said...

My first reaction to Dr. Friedman's post was feeling defensive about the purchase of my $1700 Canon 7D, but after thinking about the NEX-3 specifications I longer feel this way.

The NEX-3 is innovative in that it offers higher quality imaging in a more compact package for a reasonably low price. These are all features that I want in my next camera.

My more expensive Canon 7D offers higher image quality, in a bulkier package for a lot more money.

Where does the NEX-3 fall short of the Canon 7D in my opinion?

1) The image on the LCD screen on the NEX-3 will be really difficult to see in strong sunlight, but future models may solve this problem with a shaded loupe attachment which could be added for outdoor shooting for manual focus situations. This might add considerable bulk however.

2) Lens selection for the NEX-3 is less than for the 7D, but not that bad. The NEX-3 uses new E mount lenses. Looks like there are four prime lenses and a few zooms to choose from. The primes are

F2.8, f=16mm
F1.8, f=24mm
F3.5, f=30mm macro
F1.8, f=50mm

Cool!

3) Pixel size on the NEX-3 looks to be about 5 microns, which is bigger than the 4.3 micron pixel on my 7D, but not as big as the 6.5 micron pixel on the Canon 5D. Bigger pixels allow for more light to be collected and thus increase the amount of color in the image in low light situations for a give F-number. It also allows for sharper images at higher F-numbers.

I'm still not sold on the NEX-3, but I agree that it's a pretty cool camera. I'm excited for the future models of similar cameras. I would consider buying one of these non-dDSL cameras if lens selection and pixel size were increased. I don't think these non-dSLR will ever provide the capabilities of the dSLR, but for the money and the convenience they seem great.

 
At 7:55 AM, October 31, 2011, Blogger David Friedman said...

With reference to various comments:

I can well imagine that an optical viewfinder would be useful in bright sunlight. The main thing I have a camera for, however, is museum photography of historical jewelry, one of my hobbies being to make jewelry based on historical pieces.

For that purpose, bright sunlight isn't a problem. Being able to get good pictures in low light is.

Similarly, I can see that a really serious amateur photographer, or a professional, would want the option of spending lot of money on a collection of different lenses. From my standpoint, however, the real question was whether I wanted two lenses or one; I was originally looking for a non-interchangeable lens camera with a big sensor. The main reason for the second ("pancake") is that it makes the camera much smaller than when it has the telephoto lens attached, which in some circumstances would be convenient.

So, while I agree that there are still purposes for which the standard dSLR makes sense, I think there is a large niche, which I am part of, for which the mirrorless alternative makes more sense.

 
At 10:48 AM, November 02, 2011, Anonymous Mitch said...

I work at a office products retailer in Minnesota.

The next time an older lady stops in to look at cameras and I begin explaining the difference between 14 megapixels and 720p, I will have a hard time jettisoning these thoughts from my thoughts:

1) "Hand-held Twilight Mode takes six shots at high speed when the shutter is pressed, and then aligns and merges them into a single image, significantly reducing the graininess and noise that can degrade image quality when shooting in extremely low light. Combined with the outstanding low-noise performance of the Exmor CMOS image sensor, it lets you take exceptionally clear, beautiful, nighttime photos without using a tripod or flash."

From the Amazon description of the camera. Could someone explain how/if this is different than dSLR's (Canon Rebel, Nikon D60, Sony what-have-you, etc.) attempts at no-flash, low-light photos?

2) "Another reason the viewfinder is not so important is that cropping is so easy in electronic form. I no longer worry about framing a picture the way I did with film. I just click away, even in bright light when I can't see the screen very well, and frame later. Also it is trivial to take multiple exposures, no expense, no need to change film."

From Norm here. My opinion is that this is a "bug" of digital photography entering our reality, not a feature.

3) "When I pull an SLR, they start composing themselves (and therefore defeating the whole purpose of the photo). This also happens in street photography."

From Jose here. This also happened when I shot photos as a newspaper reporter last year, and two veteran photographers I worked with shared these experiences. What is it about the human condition that doesn't respond to photography via cell phone and pocket camera the same way it responds to dSLRs and 35mm SLRs? I've seen this play out at parties, in stranger-filled crowds (sporting events, malls) and tiny groups embarking on photo excursions. Weird.

4) "The main thing I have a camera for, however, is museum photography of historical jewelry, one of my hobbies being to make jewelry based on historical pieces."

From David here. This comment mystifies me. (Are you a nerd because few people in the world do this activity or because of some inherent quality in creating jewelry based on photographs of historical pieces in museums? Or a combination? Or are you not a nerd? [I mean this all with respect.])

 
At 1:43 PM, November 02, 2011, Blogger Unknown said...

Have you yet heard about the Lytro camera? Given the title of this post, I was surprised not to see it mentioned :-)

 
At 3:20 PM, November 02, 2011, Blogger David Friedman said...

I've heard about the Lytro, and it does indeed sound very interesting.

 
At 3:53 AM, November 13, 2011, Anonymous Andrew said...

I don't know about Sony's DSLRs, but Canon and Nikon's current consumer DSLR offerings start under $500 (with lens).

The NEX isn't cheap. Not expensive either, but price is not its distinguishing feature.

 
At 9:28 AM, December 02, 2011, Anonymous Bravin Neff said...

Clearly mirrorless cameras are the future, but the nex style (I'm a Nikon D700 shooter that also has the Nex 5n) doesn't do anything remotely what even a similarly priced DSLR does (like the Nikon D3100, $350):

1. Multiple phase detect autofocus. If you're shooting anything resembling action (wildlife, photojournalists, sports shooters, mom and pop trying to mimic any of the above with kids), the phase detect systems in SLRs kicks the mirrorless' butt. It's not even close (which is why the next waive of mirrorless sensors will have phase detect built into the taking-sensors themselves, like the new Nikon 1).

2. Optical viewfinders have no time lag. EVF finders and the back screens necessarily do, because the image is sampled and converted AD and then DA again. It's much better than it used to be, but it is certainly not instantaneous.

3. General features themselves. If you're a proficient shooter, not having direct control over shutter, aperture and ISO, immediately accessible, is a serious downgrade and time waster. Now say you give up the ability to quickly choose which focus point, change to spot metering in difficult lighting, and throw in white balance, jpeg or raw... every serious shooter wants these within one button press. My Nex 5n requires no less than three for each one, and more in some cases.

4. Of course no serious shooter thinks holding your arms out cantilever style is anywhere remotely as stable as triangulating the thing against your eye with elbows tucked in (the new Nex 7 will help there). It is not a gain to your image quality to crank up the ISO in order to counter your shakiness with higher shutter speed. Better to hold that thing securely and rely on as low of ISO threshold as you can.

But yes, mirrorless is clearly the future. Just not today, for serious shooters.

 

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