The Taming of the Shoe

The PC Sync connector

Also in this issue:

• A99's Wireless Flash Delay
• A Zeiss Full-Frame Alternative
• Seminar Update

The Taming of the Shoe

Once upon a time there were cold shoes.  Nobody called them that, but that’s what they were -- small brackets mounted onto the camera body onto which you could mount your flashbulb holder.

The original Flash bracket holder,
retroactively labeled the "cold shoe".

Once mounted, you would connect the flashbulb holder electronically to the camera via a PC Sync cord into a PC Sync socket (whose design hasn't changed much over the last century).  Inside the camera there was a mechanical switch which briefly “shorted together” the 2 wires of the PC Sync cable when the shutter was actuated.  It was a very simple and very effective mechanism, which also worked well when the electronic flash was invented.

Adding the circuitry to trigger the flash
now made it a "hot shoe".

“Hey, let’s get rid of that annoying PC Sync cable!” one engineer must have said to himself in the 1960’s, as he
devised what is now known as the “Hot Shoe” (left).  The metal rails on the bracket, coupled with the metal circle in the center, served to provide a replacement for the two wires in the PC Sync cord.  Mind you, at this stage the only thing this provided for was to tell the flash when to fire – no other information was exchanged.  The flash would always output a fixed amount of light, and it was up to the photographer to calculate the distance of the subject and use the appropriate f/stop to ensure proper illumination.   This was often a time-consuming task for each and every shot.

An auto Thyristor flash calculated
proper flash exposure on its own.

In the 1970’s, Thyristor flash circuitry was developed.  Auto-Thyristor flashes had a tiny forward-facing sensor in them (right) that would look at the subject, and when the sensor saw that the subject had enough light it would stop outputting light during the exposure.  (At this point “outputting” became a legitimate word. :-) )  This was a huge leap forward in flash technology, for it meant that the photographer didn't have to calculate or change the f/stop each time the subject changed distances.   (They still work great with digital cameras, as there's no pre-flash needed.  Just make sure your f/stop and ISO are set right.)

More automation meant more
communication pins.  Say goodbye
to standardization!

1980’s: The drawback to the Auto-Thyristor circuits was that if you had a filter in front of the lens, or if you had used a different f/stop, or if your zoom lens would actually change f/stops as you zoomed from wide to telephoto (a common thing!), then the actual amount of light that got through to the film would change, resulting in your flash pictures most likely being underexposed.  To address this problem, in the 1980’s camera companies started to move the flash sensor from the front of the flash to inside the camera, reading the light that got reflected off the film plane.  This new system was dubbed “TTL” (“Through The Lens”), and its main advantage was you could use ANY f/stop, distance, or filter (or combination of filters) and the system would do its best to ensure the flash exposure would still be accurate – no adjustments by the photographer were ever necessary.   And to accommodate this additional communication between the camera and flash, additional connection pins were necessary.

Here’s where things started to get proprietary, for a TTL flash for Nikon would not work on a Canon or a Minolta.  Here’s also where things started to become unreliable, for if the flash was not mounted and secured just perfectly onto the hot shoe, a flash exposure error would almost certainly take place.  (As a wedding photographer I saw this happen to more than one Nikon shooter - and during the days of film they had no idea it occurred until after the event.)

Minolta's solution - much faster mount /
unmount time, and fewer alignment failures.

And so, during their Decade of being Different (1990’s), Minolta decided to re-design the flash hot shoe from the ground up, to address these reliability problems.  (“Hey, there’s no interoperability anymore, so it shouldn't matter!”)  This was a good thing from a technical point of view, since it all but eliminated the kind of "almost mounted" flash failures I had witnessed, plus it made it substantially faster to mount and unmount the flash with confidence.  I liked it a lot, but the new design made it very difficult for Minolta-shooting professionals (both of them) to rent 3rd party flash equipment and radio slaves because suddenly Minolta was incompatible with everything.

When Sony bought Minolta, a flood of market research of non-Minolta/Sony shooters (the folks they were trying to court) told them to "dump the proprietary hot shoe".  And you could tell that Sony wasn't a fan of this shoe either because as time went on (most notably in the NEX-7 and A65 cameras) they let their manufacturing tolerances slip, resulting in accessory flash wobble when attached.  Between that and the flash exposure accuracy problems of the A77, A65, and NEX-7, clearly Sony's attention was elsewhere.

It turns out they had bigger problems to solve.  Sony's various camera divisions were all converging (still cameras could do video, video cameras could do stills), yet there were three distinctly different accessory shoes in use: The Alpha one inherited from Minolta, the "Smart Accessory Terminal" (hastily designed for the NEX), and the Active Interface Shoe used for the handycams (below).  Is there a way to standardize on an accessory interface and still provide new capabilities to all future cameras?

Handycam Active Interface Shoe

The new "Multi-Function
Accessory Shoe" tries to
meet all needs across all
product lines.

Sony's answer to all of these problems is the new Multi-Function Accessory Shoe first introduced in the Alpha 99 and the NEX-6.  It seems to have been designed to respond to all the criticism -- specifically, Alpha owners can now use Pocket Wizards without an adapter.  But it also has a LOT of connector pins allowing for diverse peripherals to attach and communicate with the camera.

These pins, while stiff, look 
vulnerable and I'm not looking 
forward to having to 
pamper my equipment.

What kind of peripherals?  For starters there's the professional audio mixer (the XLR-K1M, which I've used and liked), a future add-on GPS or Wi-Fi, or an add-on EVF or external HDMI display (I assume most future lower-end cameras won't have all these things built-in).  Plus power pins to power all these accessories.

Do I like the new design?  Not especially.  It now takes more time to mount / unmount a flash, and I no longer feel comfortable just throwing the unmounted flash into my camera bag (like I used to when I was a high-pressure wedding photographer) for fear of those little unprotected pins getting bent.  Time will tell just how susceptible these are to damage, but I'll tell you now I'm not looking forward to having to pamper my accessories.  (Preemptive strike: No, I don't use lens caps, either.  They slow me down.)

Wireless Flash Delay

I'm still getting used to my new A99, which offers the best image quality of any camera I've ever owned at any ISO.  I'm overjoyed that the dreaded flash exposure accuracy problem which plagued the A77, A65, and NEX-7 (which went unacknowledged by Sony) has gone away, but it has been replaced with a lesser problem that for me is just a pain: The wireless flash feature has an inexplicably long delay.  (The NEX-7 had this too, but I never expected this camera to be as responsive as a high-end shooter.)  Is this important?  It is for me, but then again most people don't use wireless flash to shoot kids the way I do.  Here's a quick video clearly demonstrating the artifact so you can decide for yourself:

I highlight these problems with a bit of trepidation, since as an engineer I understand just how insanely complex these cameras have become, and I have to acknowledge that Sony got the really hard things right.  (It's just frustrating that they can't seem to re-implement a 30-year-old technology properly.)  The camera also has a flash sync speed of 1/200th of a second when using the PC Sync cord or anything other than a Sony or Minolta accessory flash (the advertised speed is 1/250th of a second.)

Emphasizing these small problems might send the wrong message regarding all the unique positive things this camera has to offer.  (So to balance things out, let me state up front that there's no oil drops on the sensor! :-) )

A Zeiss Full-Frame Alternative

For those of you concerned about the cost and the 2-pound weight of the "Standard" Zeiss 24-70 f/2.8 lens for your full-frame camera, consider this alternative: Konica Minolta once made a 28-75 f/2.8 constant aperture zoom lens that is 98% of the Zeiss optical quality at about half the weight and one-fifth the price.  Pretty good trade-off if you asked me. (There are Sony and Tamron versions too which are more expensive but still great optical performers.  Kurt Munger seems to favor the Tamron version.)

Seminars

Surely you've heard about the seminars by now!  (If not: http://FriedmanArchives.com/seminars)  They seem to leave an impression on all who attend - even those who have attended other seminars in the past.  Here's what's on the calendar for 2013 (exact dates still to be determined):

• Singapore will occur in March (tentatively March 23-24)
• Seattle and British Columbia (no, I'm not sure where yet) in June
• Australia (Brisbane and either Sydney or Melbourne) and Rotorua, New Zealand in October

As mentioned before, I'm restricting the seminars to about 4 major trips a year to maintain a healthy work-life balance.  We can still consider one more for the coming year, and if you're a camera club you can help make it happen sooner.  Contact me at Seminars at Friedman Archives dot com.

Next Month

Next month I'm going to share with you what I've learned about the new frontier of making e-books for the various e-readers (It's not for the faint of heart, and there are NO good tools out there to aid the poor author who doesn't have a background in programming!) (It was a pain even for me, and I used to program for a living!)

I'll also have status updates on the upcoming e-books for the Alpha 99 and NEX-5R and NEX-6.  Stay tuned!

Yours Truly,
Gary Friedman

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You didn't think I'd get in a blog post without mentioning Cameracraft Magazine, did you? :-)  http://friedmanarchives.com/cameracraft