Notes on using a flash with the digital Pentax *ist line.

2006-08 comments are collected from the internet from various forums
2006-10-17 reformated a bit

Re: *ist DL flash compatibility question
Roland Mabo 
The *ist DL and DL2 are only compatible with Pentax P-TTL system (Pentax
AF360FGZ, AF540FGZ and Sigma EF500DG and EF500DG Super - I recommend all
of those except the Sigma 500 non-Super because it lacks support for
highspeedsync flash and wireless flash). The *ist D, DS and DS2 also
supports the older Pentax TTL system, with mixed results (because of the
different light reflection characteristics between film and the digital
sensor). But your AF160SA flash is not a TTL flash at all. It is a
program auto flash which relies on a thyristor cell inside the flash. It
will work with all Pentax *ist bodies. The designation "SA" means
"Sensor Automatic". Standard TTL flashes has a "T" in the designation
(for example: AF280T, standard TTL analogue protocol, AF500FTZ, standard
TTL digital protocol). Pentax P-TTL flashes are the FGZ serie (F = focus
assist beam, Z = auto zoom for the flash unit, G = new generation TTL
(P-TTL), very unlogical but I guess FGZ sounded better than FPZ... :) )
Take care* R 


Some clarification on DL flash compatibility
JJJPhoto - 4 months ago
The DL and DL2 use P-TTL circuitry for "Through The Lens" flash
metering. This means that there is a short monitor pre-flash that occurs
a split second before the actual exposure flash. Most people can't
distiguish between the pre-flash and the exposure flash, but some claim
it causes people with sensative eyes to blink. (Most people who claim a
serious problem with blinkers have never even used a P-TTL flash.) I've
been using Nikon DSLRs for a number of years and the Nikon iTTL flash
system uses a preflash identical to the Pentax P-TTL system ... and I
haven't had problems with "blinkers" with my Nikon gear. Anyway, if you
don't want to buy a P-TTL compatible flash you can still use a TTL flash
on the DL ... just not in TTL mode. You'd have to switch the flash to
Auto or Manual mode. I've used the Vivitar 283, Nikon SB-800, and Nikon
SB-28 flashes in auto and manual modes and they work perfectly.

Re: Some clarification on DL flash compatibility
Roland Mabo - 4 months ago
JJJPhoto wrote: 
> The DL and DL2 use P-TTL circuitry for "Through The Lens" flash 
> metering. This means that there is a short monitor pre-flash that 
> occurs a split second before the actual exposure flash.

(it's also used by D and DS). The pre-flash is read by the cameras 3D
multisegment metering for ambient light. Flash TTL means a light meter
cell underneath the mirror which reads the light reflected from the film
or digital sensor. The DL and DL2 does not have this extra light
measuring sensor, therefore they only work with P-TTL flashes. 

> Most people can't distiguish between the pre-flash and the exposure flash

True, when I first tried my P-TTL Sigma EF500DG Super, I thought that I
had god a dysfunctional flash, but everything was correct. I just
couldn't see the pre-flash, it appeard as one flash to me. :) 

> Anyway, if you don't want to buy a P-TTL compatible flash you can 
> still use a TTL flash on the DL ... just not in TTL mode. You'd 
> have to switch the flash to Auto or Manual mode.

That depends on the flash, not all TTL flashes supports sensor
automatics. Pentax newer TTL flashes - the AFnnnFTZ flashes, the
generation before Pentax switched to P-TTL, does not support sensor
automatics. Pentax first generation of TTL flashes - the AFnnnT serie -
supports sensor automatics ("program auto flash"). Most units can be
used in manual flash mode. Take care* R

Re: Some clarification on DL flash compatibility Roland Mabo - 4
months ago Anastigmat wrote: > The Vivitar Series 1 840P flash for
Pentax AF cameras lack a > sensor.

Well, I was talking about Pentax flashes. :)

> So does the Pentax AF220T. So, you are slightly 
> inaccurate in your generalization.

The AF220T was released as a cheap alternative to the AF330FTZ, it's not
part of the original AFnnnT serie (AF220T, AF280T and AF400T) despite
the fact that it uses the old AFnnnT designation. It was the recommended
flash to be used with the MZ-10 in the mid 90's (the original AFnnnT
serie was released for the Super A/Program Plus in the early 80's). I'm
sorry if I was unclear about this. Take care* R


Re: *ist DL flash compatibility question
Roland Mabo - 4 months ago
Anastigmat wrote: 
> New generation? Is this official or did you make it up? What 
> about FTZ? What does the T stand for? 

Ok, lets repeat it then... 

AFnnnSA = Auto Flash approx guide no Sensor Automatics 
(for example, AF160SA). To be used with, for example, the P30, P50, MZ-M
and MZ-60.

AFnnnT = Auto Flash approx guide no TTL flash 
(for example, AF280T). Pentax first generation of TTL flash, uses
analogue TTL protocol. To be used with, for example, Super A/Program
Plus.

AFnnnFT = Auto Flash approx guide no Focus assist beam TTL flash 
(for examle AF400FT). Pentax first flashes for the autofocus bodies. To
be used with SF1, SF7 etc.

AFnnnFTZ = AutoFlash approx guide no Focus assist beam TTL flash
autoZoom. (for example AF330FTZ). Pentax 2nd generation of flashes for
the autofocus bodies, now has an auto-zoom function which adjusts the
flash beam after the focal length in use. Introduces digital TTL
protocol, which means that they can't be used on Super A/Program Plus.

AFnnnFGZ = Auto Flash approx guide no Focus assist beam newGeneration
ttl autoZoom. For example: AF330FGZ. P-TTL compatible, introduced with
the MZ-S, also works with MZ-6, film *ist and the *ist DSLR serie.

Take care* 

Re: *ist DL flash compatibility question
Godfrey - 4 months ago
Sinnettc wrote: 
> I'm getting ready to make the jump to a *ist DL frpm my KM-Z6 
> ultrazoom & Pentax ZX-60 SLR. I have a Quantaray bounce flash with 
> a KM base (I can order a Pentax SLR compatible base for it) and an 
> old Pentax AF160Sa flash that I'd like to use with the DL I'm going 
> to order. The KM base turned out to be marginally compatible with 
> KM's eTTL system (it fires but I have to shoot in manual mode). 
> Does anyone know if the *ist series are backwards compatible with 
> Pentax's SLR TTL system? 

The DL body only supports Pentax-dedicated flash metering with flash
units capable of supporting the P-TTL flash metering system. Older flash
units supporting older, simpler forms of TTL flash metering will not
perform any flash metering with the DL. Your Quantaray bounce flash and
Pentax AF160Sa will only operate in manual mode or with their built-in
autoflash sensors, if so equipped.
What is commonly referred to as "TTL flash metering" is metering the
flash at exposure time, reading reflection off the film/sensor gate, a
30 year old flash metering technology pioneered by Olympus and Minolta.
This system is widely accepted to be less consistent in use with digital
sensors than the now-standard TTL systems that do a preflash and
integrate readings from flash and ambient light prior to making the
actual exposure (Canon: E-TTL, Pentax: P-TTL, Nikon: i-TTL, etc). Older,
higher end Pentax DSLRs support this old-type TTL flash metering
primarily for backwards compatibility, but the feature has been dropped
from the DL model to reduce the body's price. Most users of older TTL
flash units report that consistency is poor on the D and DS bodies.
However, the question of whether the older TTL flash metering is better
or worse is irrelevant to your question. The answer to your question is
that your current flash units will not work as they were designed to on
the DL body, you need a new P-TTL flash unit to utilize TTL flash
metering with the DL. The Pentax AF360FGZ and upcoming AF540FGZ, and
Sigma's EF 500 DG Super, are the current options for maximum
compatibility/functionality with the DL.
Godfrey 


Re: *ist DL flash compatibility question
Godfrey - 4 months ago
Anastigmat wrote: 
> 
> Widely accepted by whom? By Nikon and Canon executives I suppose. 
> Fact is, Olympus uses it in the 4/3 DSLR, Fuji uses it in the S2 
> Pro and Pentax uses it in the *ist D, DS and DS2 but not the DL. 
> The DL is the lowest priced camera in the Pentax DSLR lineup. It 
> would be nuts to put the best flash system in the lowest priced 
> camera. Fact is, Pentax, Olympus and Fuji owners are grateful for 
> the flexibility of TTL flash. I know some doctors and dentists who 
> buy Fuji S2 pro cameras to use TTL flashes with their Nikkor 
> lenses. Pentax users are lucky that Pentax believe in the TTL. My 
> prediction that the 645D will also support TTL flash, 
> notwithstanding those who keep spreading rumors that TTL flash is 
> somehow unreliable on DSLR cameras. 

A, 

Your response is quite predictable. 

TTL, P-TTL, i-TTL, E-TTL, etc are all TTL (through the lens) metering
flash exposure automation systems. Whether you choose to believe that or
not, it is a fact. Same goes for the other folks who assert that I made
a mistake calling them that in another thread.
"Time of exposure" TTL flash metering, reading off the film plane, as
developed by Olympus and Minolta in the 1970s, is a very old system that
still has applicability under particular circumstances. However, it is
well accepted amongst professional and advanced amateur photographers
that it is a less consistent system than the later TTL flash metering
systems, and particularly in regard to use with digital sensor camera
bodies. The area in which it has the greatest applicability is in macro
work as it reduces the need to do calculations of extension factors for
high magnification work, which is probably why your dentists and doctors
like it. Dentists and doctors are generally not professional
photographers, what they need for their work is somewhat more
specialized than general purpose photographic endeavors.
This type of TTL flash metering is supplied in those cases where it is
for reasons of compatibility with existing flash equipment. I can easily
imagine Olympus supporting it as they are considered the original
inventors (although I understand that Minolta has a competing claim in
patents from the same time period).
Preflash TTL systems, which take into account ambient and flash
integration, distance calculation, and matrix evaluative metering
systems in modern cameras, produce more consistent, better adapted flash
exposure automation. The downside of preflash TTL systems is the
muscular response in some people which causes a blink to coincide with
the moment of exposure.
It's silly to debate that the old, simpler system is more sophisticated
and "The Best". It has its realm of applicability, like any other
technology. A photographer doing a lot of people work will often want a
different flash metering solution to avoid eye blink, a photographer
doing macro photography might find traditional TTL flash automation
suits their needs best, other photographers (myself included) find that
it's often simpler and easier to use a hand-held flash meter and work a
flash setup manually.
But there's a reason why these later variants of TTL flash metering came
into being, and it wasn't just Nikon or Canon (or Pentax, or Minolta,
etc etc) looking to make more money from poor photo-equipment-addicted
wretches. It's because there are problems with simple TTL flash
automation that they were looking to solve to satisfy the customers who
were running into them, in order that those customers would have greater
satisfaction with their products and buy more as a consequence.
This doesn't matter to me enough to continue to debate with you. I tend
to use flash very infrequently and mostly manually setup flash
situations at that. The answer I gave in this thread was to the original
poster's question: it is factual and accurate. Opinions reflected in it
are the opinions of the majority of flash users, not the repetitive rant
of a fringe niche.
I will not respond to you any further in this thread. 

Godfrey 

Re: *ist DL flash compatibility question
Roland Mabo - 4 months ago
One of the many reasons for Pentax to develop the P-TTL system, was the
fact that many photographers with the other brands (especially Nikon and
Canon) looked down at Pentax and claiming that Pentax had a "poor flash
system". I remember several discussions during many years prior the
P-TTL system, where many said that they had left Pentax or wasn't
interrested in the Pentax system, because they believed that Nikon 3D
matrix flash and Canon's E-TTL was superior flash systems.
P-TTL is a technically more advanced system, but it's easier to
implement than TTL flash because it relies on electronics already there
(like the multisegment metering) where TTL flash needs an extra sensor
(= cost extra money).
I started using my DS with AF330FTZ flash, but when it died last summer
(electronic failure due to two humid, wet and cold weeks at a
yogafestival were I camped) I bought the Sigma 500DG Super. I was happy
with the results from my AF330FTZ, but I'm even more happier with the
Sigma Super. As my AF330FTZ is no more, has climbed up the ladder, has
said goodbye, has throwed in the towel, has resigned, has walked around
the corner, has entered it's last journey, has found peace in the flash
heaven (etc etc), I can't make a direct comparision and test - but it
seems to me that I get more consistent exposures with my Sigma (although
it does overexposes by 1 stop with Omnibounce).
Take care* 
R 

Re: *ist DL flash compatibility question
Anastigmat - 4 months ago
Godfrey wrote: 
> 
> Roland Mabo wrote: 
> > P-TTL is a technically more advanced system, but it's easier to 
> > implement than TTL flash because it relies on electronics already 
> > there (like the multisegment metering) where TTL flash needs an 
> > extra sensor (= cost extra money). 
> 
> Hi Roland, 
> 
> P-TTL still requires a flash sensor ... they are generally 
> different from ambient light sensors. 

P-TTL uses the same light sensor in the viewfinder that is normally used
to measure light during non-flash photography. That is why there is a
preflash with the mirror in the down position. So that the reflections
from the preflash can be measured by this light sensor and the
calculations of the flash duration can be made. One fewer light sensor
means cheaper manufacturing cost. P-TTL is cheaper to make, and that is
the main reason why the DL is P-TTL only. Pentamirrors are also cheaper
to make than pentaprisms. That is why the DL has a pentamirror.
Pentaprisms have been around for even longer than TTL flash, I guess
that makes them inferior to pentamirrors, which are much newer,
according to Godfrey's logic. LOL.

SMC Pentax-F 1.7x AF Adapter
brian thomson - 4 days ago
This is an odd one that I picked up for my film Pentax years ago, but
still works fine with my DS. It works with manual lenses, giving them a
limited AF capability at the same time. You focus manually, then the AF
in the adapter does a "fine focus". So, for about £20, it's turned my
£15 SMC P-A 1:2 50mm in to a 84mm F3.5 AF, effectively. I don't have any
shots to display - I ought to use it more!
-- 
brian thomson 
dublin, ireland 


R