Friday, March 14, 2014

Mirrorless: Transcending D-SLR and reaching a higher plane technological progress

There were a lot of very smart and skilled photographers whom I felt made bombastic statements about the premature death of the mirror based D-SLR cameras and rejoiced the onset of mirror-less versions in the last 2 years.
Regarding these silly statements I can only think of one reply that sums the situation best, a paraphrased quip from the notable Mark Twain "Alas the reports of my death have been greatly exaggerated!".

I am not new to technology,  I've seen a lot of good and some bad ideas, come and go.
Mirror-less is a fantastic step forward in technology, however mirror based digital cameras have been around for a very long time. It's a very mature technology and they have had plenty of time to work out most of the kinks.
I do agree with the sentiments of those who rejoiced the appearance of high quality consumer mirror less-cameras, traditional D-SLR technology is stale and approaching it's pull date.

The mirror-less cameras that I'm seeing are innovative, some of them are very impressive, however they do not deliver crushingly good results when compared to their heavier and more mature mirrored brethren. The results are good enough in some cases that the weight savings is well worth the trade-off of not using a larger high powered full body camera.

It will be at least another 6 years of constant re-investment and development in this technology before it gets to the stage where it will surpass even the very best pro-body cameras available today.

Lately the trendsetters in the mid to high end prosumer category of mirror-less cameras is Olympus, Sony and perhaps Nikon. The most notable one is Sony's Alpha 7 series.

What will it take for us to attain this level of technological enlightenment and what is holding us back?

I have a few ideas but first I think it would be helpful to highlight the various core technologies that make up a modern D-SLR system.

Shutter Systems:

  1. Focal Plane Shutter:
The most popular shutter system implemented today, it also is a major design handicap that will hold back advances in camera performance. To change it would require vast infrastructure changes in the lense designs of most consumer and professional consumer (pro-sumer) cameras. That is why it's highly unlikely the system will fall into disuse any time soon. The majority of TTL Sync speeds are almost all limited to 250 with pseudo operations at higher speeds producing unreliable results.

  2. Leaf Shutter
Leaf shutter is a very complex system but it offers far more advantages to the photographer, namely higher shutter sync speeds with on and off camera flash systems. It's a rare commodity in all but the most expensive camera and lense combinations on the market today. They have been able to offer photographers TTL Sync speeds up to 1600. The higher sync speeds allow it to be used in outdoor areas where the lighting can't be controlled, wedding photographers drool over an ability like that.

  3. Digital Shutter:
Digital shutters are typically used in camera phones, C.O.C' (camera on chip) and a few D-SLR's.
Their actual function is something of a mystery to me, but the link above to a wiki page should offer some enlightenment. Kodak and a few other companies have dabbled with this in DSLR camera bodies but did not keep it in their camera line-up. They have the distinction of being completely free of moving parts and can actuate their shutter at speeds measured in nanoseconds.

View Finders:

OVF - Optical View Finder
  • Requires no power, remains useable whether the camera is powered on or not.
  • Provides you with a real time view similar to your own eye of what the camera can see.
  • Ability to perceive parallax (spacial relations of objects in your view finder).

EVF - Electronic ViewFinder
  • Lack of parallax and ability to cope with high zoom-ratio lenses, without the need for a bulky reflex mirror. Cameras with a separate optical viewfinder show the scene from a different viewpoint than that of the camera lens.
  • Information about the scene, such as a histogram, can be overlaid with the scene.
  • EVFs can show approximately how the scene will look under the chosen exposure during day or night.
  • EVFs can show a low-light scene brighter than it is when they are display-priority.
  • Most EVFs show 100% coverage of the final image.
  • EVFs provide a more accurate depiction of the contrast, white balance and color saturation that will appear in the final image.
  • EVFs can provide the focus peaking feature that highlights areas of the frame that are in focus.
  • Unusable while the camera is powered down.

On Camera Digital Displays:


I will try to outline the various display technologies in summary, they are complex and an in depth review of them is beyond the scope of this article.

  1. LCD is the oldest flat panel display technology currently and still widely in use. It does a fairly good job of displaying the color gamut and giving decent contrast.

  2. LED is the next generation of flat panel display technology, it has low power consumption compared to normal LCD, and better overall color reproduction as well as contrast. It can be made much thinner due to less complex manufacturing. They produce much less heat than traditional displays, heat is the enemy of cameras. The most common configuration for LED monitors is using them as a backlight source in LCD monitors.

3. O-LED is the most cutting edge display technology available currently. Not only does it provide excellent color reproduction and dynamic range (contrast) but it does not require a third party device as a light source since it combines the abilities of an LCD panel's color reproduction with the light generating capabilities of a traditional backlit LCD, all on the same substrate (silicon platform). It also has the unique characteristics of being highly malleable, even bendable, allowing it to be used in all kinds of shapes. It is the most energy efficient and optimal display for integration into cameras and other devices. In short it generates all of it's photons (light and color) based on the electrical charges that stimulate the matrix of cells on a O-LED panel in very tiny clusters. These also have a very small thermal foot print.
Basic visual explanation of how a O-LED panel is structured.

Camera Sensors:

CMOS Camera sensor.

I am no engineer but I can certainly outline the no-nonsense things behind the CMOS sensors and what makes them tick. They come in all shapes and sizes, the majority of the cameras on the market are powered by sony made sensors.

The phrase "size matters" is a drastic oversimplification where digital cameras are concerned.

Pixel pitch will almost always trump sensor size (pixel count) every time. The pixel density or "pitch" as it's referred to greatly affects the sensors ability to collect light. The Canon 1DX, 5D MkIII, Nikon D4 and D3 are good examples of lower pixel count sensors that perform very well despite their diminutive size when compared to medium format cameras.

Larger sensors have a few advantages:
The first is the ability to produce very high definition pictures and the second is that a larger sensor has higher tolerance for pixel failure (hot pixels).

When a sensor ages more of the areas on the sensor start to fail, resulting in remaining switched on permanently or unable to turn on.

Modern digital cameras have an ability listed in the OSD with a misleading title, it's called sensor cleaning. Essentially when activated it attempts to map the malfunctioning portions of the chip and exclude them when it captures images.

Removing actual dust and dirt requires physically cleaning it with a squeeze bulb and sensor swabs.

Scientists use cryogenically cooled camera sensors for applications like astrophotography, the reason is because heat is a major source of image fidelity loss. The sensor heats up during prolonged operation, for instance long exposures.

OSD Menus:
"Yo dawg I heard you liked menus of your menus in menus of menus!".
Camera makers rejoice in the needless complexity of categories and menus, making what seems like such a simple and mundane task, time consumingly irritating. Attempting to quickly access certain features on my D800E sometimes feels like navigating a labyrinth. There are a number of functions I don't even use because of this.

According to users of exotic cameras such as Leica, Mamiya, and Hasselblad - some of these cameras have mastered the art of simplifying menu navigation.

I haven't checked but I recall there might have been an option to remove menu's you don't use in the Nikon OSD setup, if there isn't then perhaps Canon and Nikon should give that idea further consideration.

It is practically written into human DNA, an almost OCD-like impulse to categorize everything and as a result of that, over complicate simple tasks. People do not set out on a task with this goal in mind but it is often the end result.

In order to truly kill the beast that is D-SLR a mirror-less version would have to incorporate some or all of these changes:
 - Advanced O-LED displays in both the viewfinder and the on camera display capable of high dynamic range.
 - A 16 bit or better RAW format (uncompressed)
 - High speed (500+) focal plane shutter system.
 - Full frame or larger sensor with no vignette issues.
 - 4k Video

Is the mirror-less peerless? No but is making very solid progress towards that goal..