whats in a name?
By Ralf Engelmann
SAFOX, or more correct SAFOCS means in official Pentax language: Sensor Ability
Fortifying Optical Compensation System. This of course is only another marketing language
excess for an ordinary phase comparison principle autofocus system. It derived from the
late 80's when such tech slang was very much in fashion. Pentax created more such horrible
terms, like CENTIC for the prism cap located LCD-monitor or PROCES for an integrated
metering system with automatic backlight compensation. Pentax stayed with the term SAFOX
for their autofocus system also in the (P)Z-series and the MZ/ZX-series. (P)Z-series had
SAFOX II, clear, since this was Pentax second AF-camera system (I skip ME-F here, but I
will mention it later). For the rest of the world this was the so called third generation
autofocus systems, because from early 90's on predictive AF with good light sensitivity
and fast reaction times were the new standard. Due to Pentax's late start in AF this was
now SAFOX-II. It was updated several times in terms of software logic and motor speed, but
the sensor itself stayed the same, and so did the name.
With MZ/ZX-5 in the mid 90's the number of detection fields were increased to three. At
Pentax the detectors are still in one line on the sensor chip, so in principle it's still
a pure vertical pattern detector. But a clever mini-prism and mirror arrangement in front
of the sensor changes the orientation of the outer fields for horizontal detection,
forming a "H" with the middle sensor. With another front optics arrangement, one
can form also a "+" or a "x" or a "-I-", there is a lot of
room. Unfortunately they didn't use the "+" option on the cameras without
AF-spot switch, but that's another story. This AF-system is called SAFOX IV. Yes IV. there
is no SAFOX III. Either it was a cross sensor prototype that was shelved (technical
problems? Patent situation?) or it was the passive 5-beam AF-system that was developed for
the zoomcompacts in 1994. Anyway. The new MZ/ZX-50 has now a system SAFOX V, again with a
single sensor area, so this is very similar to SAFOX II, but for marketing reasons Pentax
wanted a new name.
How was the name SAFOX invented? Officially there is the version that there was the new
SAFOX-system, and therefore the according first AF-camera series was called SF. Like
SaFocs (another possibility would have been SOCS...). Now, sensor ability fortifying and
so on is a very complicated way to describe a modern AF-system. So I believe this is all
nonsense. I think, the SF-series had a kind of working name during development. This was
combined from the first Pentax AF-camera ME-F and the mid-line top model Super-A/Program.
So it was called Super-F. SF. And later a poor guy in the marketing department had the job
to create a name for an AF-system including these letters. Not only SF (sensor fortifying
is o.k. in principle), but also the X, because in international market the first SF-camera
was named SF-X (from KX, MX, LX and so on). X... o.k., compensation system! but
"SSFFXX" is different to spell - lets include some vocals. Optical. Ability.
Ability. Optical. And so on.
|Note by the author: maybe this is all wrong and they
are really so crazy to call a simple AF-system "sensor ability fortifying" ...
which reminds me a little bit at terms like "taste enhanced"...
By Ralf Engelmann
A classical question in Pentax AF history is why the version numbers of the AF systems
jumped from SAFOX II in the (P)Z-series to SAFOX IV in the MZ/ZX-series. So far no one had
a real explanation for this nomenclature, but some rumors were around: 1st, SAFOX III
could be a silent update in software logic speeding up SAFOX II speed in (P)Z-1P and
(P)Z-70 cameras, but since the sensor stayed the same, Pentax didn't change the official
designation. Or, 2nd, SAFOX III was the passive 5-point AF system designed for the 1994
zoomcompacts, but also not mentioned officially. Or, even, 3rd, the whole thing was simply
a marketing trick; the jump from II to IV should indicate how new the MZ/ZX-5s AF-system
A look at the AF-technology patents hold by Pentax gives another explanation. If SAFOX
III exists, it should be dated after 1991 and before 1995. It is very much surprising to
see that Pentax has several patents on hyper modern AF-technologies deriving from this
time. Most of them were not realized in the known cameras, so these patents can be
considered to be the mythical SAFOX III.
What is the technology described in these patents? Well, a big surprise. Pentax was
amongst the first to develop a three field eye controlled cross sensor AF-system. The
first patents deal more with the three field AF, then the eye control came in and later
the eye control was improved.
The latest patents deal with the question how to miniaturize such a system to work in
cameras with small bodies. So Pentax was not only amongst the first doing research in this
field, they also constantly developed it further.
One might speculate now why such a system was not included in (P)Z-1P's update in 1994.
At least the three field AF should have been functional. Maybe they thought about the
whole thing only in terms of a complete system, and since eye control wasn't ready, they
didn't include it in (P)Z-1P. Later then MZ/ZX-series happened, so again development
efforts were necessary to make the whole system smaller. Or they shelved the whole idea,
since a three field eye control system was meanwhile a technology for middle class cameras
like Canons EOS 50/Elan II, whereas the new pro cameras suddenly had no eye control
anymore, but a 5-field AF-systems with a thumb selector. The story itself makes the
MZ/ZX-1 saga of course even more interesting, since the big question is now: Was (P)Z-1P
only an intermediate in the constant development of an SAFOX III camera, becoming
necessary because of development delays? Or is the whole thing a matter of history
meanwhile, and Pentax only holds the patents to tease Canon and to hinder them to make
smaller cameras with eye control?
By the way, the delay between development and patent is two years or more, so we still
have no insights what Pentax or the other companies are doing at the moment. On the other
side, it's also a long way from developing a prototype to a serial product. So the patents
can give some hints, but not a clear image what will happen in the camera industry in
|Note by the author: Of course all the developers and
product managers know the patents of the other companies very well, since patents are open
for insight and most of the patents have been available in Japan much earlier than
internationally. Also patents are very much a tactical thing, so sometimes important
techniques have no patents, because the thing is so new that the other companies have to
invest several years of research to catch up anyway, and sometimes less important things
have patents, since companies want to hinder others to do it a similar way.
original articles were published on SPOTMATIC magazine #15, January 1998.