[VSTAR]

I am going overseas and wanted to give someone a gift for their new griii, a small Pentax flash unit.

Does anyone know if the older 200fg flash is fully compatible with the camera. Ricoh only lists the newer 201fg and the other 2 newer ones, and even states in one discussion not to use the 200fg.

While there are discussions on this site about it...no one has stated if they have actually tried it on their griii.

Thanks.

[stevebrot]

Does anyone know if the older 200fg flash is fully compatible with the camera.

The flash specification for the GRIII is that it supports the Pentax P-TTL flash protocol. As such, any current model Pentax flash should work as will several other third-party flash. Given that the AF200FG is only $10 USD less money than the AF201FG, the latter would be my choice between the two since it offers bounce capability and is both smaller and lighter than the AF200FG.


Steve

[aaacb]

It works, though it's a bit large and heavy to comfortably hold the camera with just one hand in the grip.

[VSTAR]

The flash specification for the GRIII is that it supports the Pentax P-TTL flash protocol. As such, any current model Pentax flash should work as will several other third-party flash. Given that the AF200FG is only $10 USD less money than the AF201FG, the latter would be my choice between the two since it offers bounce capability and is both smaller and lighter than the AF200FG.


Steve

Reason I was asking ...a used 200fg is $20-40 here and 201fg is only available new.

Last, any reason Ricoh does not include the 200fg being compatible and actually stated on one website that it was not usable on the camera (other than wanting to sell newer product)

[kaseki]

Reason I was asking ...a used 200fg is $20-40 here and 201fg is only available new.

Last, any reason Ricoh does not include the 200fg being compatible and actually stated on one website that it was not usable on the camera (other than wanting to sell newer product)

Suggest an internet search and downloading from one of the Pentax guide sources an AF-200FG user manual and determining whether it supports P-TTL or only TTL.

[stevebrot]

Suggest an internet search and downloading from one of the Pentax guide sources an AF-200FG user manual and determining whether it supports P-TTL or only TTL.

It was released in 2007 and supports both TTL (digital protocol) and P-TTL as per the review section on this site and the user manual. The product listing at B&H only mentions P-TTL.


Steve

[kaseki]

It was released in 2007 and supports both TTL (digital protocol) and P-TTL as per the review section on this site and the user manual. The product listing at B&H only mentions P-TTL.

Steve

I'm not sure what you mean by digital protocol for TTL, but I am hoping you will expand my knowledge. My present understanding is that in TTL mode, the camera initiates the flash (by pulling down (electrically) the center contact) and then quenches the flash (by back pulsing the SCR gate using another terminal) when the camera detects sufficient light has reflected from the film plane. I would think of this as an analog protocol. It is the way TTL worked as far back (for me) as the Nikon FG. Perhaps there is also a digital signal available for communication, but I don't expect it to be part of the TTL action. It could, of course, set some parameters such as the flash beamwidth if the capability were there.

[VSTAR]

I'm not sure what you mean by digital protocol for TTL, but I am hoping you will expand my knowledge. My present understanding is that in TTL mode, the camera initiates the flash (by pulling down (electrically) the center contact) and then quenches the flash (by back pulsing the SCR gate using another terminal) when the camera detects sufficient light has reflected from the film plane. I would think of this as an analog protocol. It is the way TTL worked as far back (for me) as the Nikon FG. Perhaps there is also a digital signal available for communication, but I don't expect it to be part of the TTL action. It could, of course, set some parameters such as the flash beamwidth if the capability were there.

I am now going to enroll at University for electrical engineering ! Just kidding! Thanks for the explanation.

Now... from the Ricoh website about using a flash unit with the camera

"You can discharge a flash for shooting when a flash unit(optional) is connected to the camera.
・The following flash units can be used.
PENTAX AF540FGZ, PENTAX AF540FGZll, PENTAX 360FGZ, PENTAX AF360FGZll, PENTAX AF201FG"

Is the 200fg just left off the list in order to sell a newer model or do they know something we don't?

[stevebrot]

I'm not sure what you mean by digital protocol for TTL

It is secret knowledge! Starting in 1980, Pentax began use of a four-contact (center, ready, mode, and ground/rail) hot shoe that debuted on the LX and continued on the A-series, P-series, and 645 cameras. Initial TTL support was provided using this shoe on the LX, Super Program, and 645 using so-called analog dedication. The body holds the "mode" contact low until sufficient light has been detected at the film plan, signaling "quench" to the flash by setting it high. In 1987, a second (digital) dedication/TTL protocol was added to the line using a five-contact (center, ready, mode, data and ground/rail). This second protocol allows for purely digital flash dedication and TTL flash with the five contact flash continuing to this day. As hinted by the name, the digital protocol used the data pin with the other contacts used for legacy support.*

This is where things get interesting in that there were soon three different levels of support from flash (analog only, digital only, and either) as well as three levels of support from bodies. The analog protocol along with supporting flash had a very long life courtesy of the long-lived LX camera and analog-only flash were similarly long-lived. I don't know for sure when the AF400T, AF280T, and other analog models left the shelves, but I do know that body support continued through to the MZ-S (introduced 2001). Flash support for analog protocol bodies continued through to AF360FGZ and AF540FGZ. Yes, the AF540FGZ will work quite seamlessly doing TTL on my 1983 Super Program. I believe that the AF200FG is the last model that supports digital TTL.

Well, there you have it...TMI? Today we have only P-TTL, but strangely enough our dSLR bodies retain remnants of analog protocol dedication support. My AF280T will quite happily tell the K-3 it is there and what aperture to use for auto-thyristor flash with the currently set ISO...even auto-ISO.


Steve

* EDIT: This is purely an assumption on my part and not based on testing with digital TTL gear.

[stevebrot]

Is the 200fg just left off the list in order to sell a newer model or do they know something we don't?

The truth is out there, but as noted above, at least one user on this site has used the AF200FG with no ill effects other than peeling skin on the backs of their calves and buttocks and the comment that it was a bit large and heavy. (@aaacb)


Steve

[kaseki]

It is secret knowledge!...
[good stuff deleted for space]

Steve

Thank you! Interesting and clarifying.

However, since the whole object of TTL is to measure light at the film plane by inference from the film reflection to a TTL detector system in the camera and to stop the flash when enough energy has been detected, the control of the flash has to be dynamic. I can hardly believe that the quench command itself is digital. One has to operate in the microseconds or tens of microseconds regime to get the net illumination of the film plane into the desired exposure region. Your description doesn't explicitly preclude use of the mode pin for quenching even though all other flash actions and reactions might well be communicated through the data pin.

So, Steve, are you sure that the quench is performed via the data pin, or did I misunderstand you and you really intend that digital TTL just means more camera-flash integration and that the mode pin is still used?

[stevebrot]

I can hardly believe that the quench command itself is digital. One has to operate in the microseconds or tens of microseconds regime to get the net illumination of the film plane into the desired exposure region.

I get what you are saying, but if I were writing the protocol, I would send the command to fire and the flash would wait for a single bit to quench.

Your description doesn't explicitly preclude use of the mode pin for quenching even though all other flash actions and reactions might well be communicated through the data pin.

That is true and without a digital TTL camera and flash to test with, I have no way of confirming. What I do know is that digital-only TTL flashes such as the AF200FG will not do TTL with analog-only TTL bodies. FWIW, my statement is based in part on the language used on KMP (K-mount page) site's page on hot shoe/flash evolution where digital control of "F" flash is explicitly stated.

kmp.pentaxians.eu/technology/hot-shoe/

Good as the resource is, that page has not been updated to include P-TTL technology, though there is inference that while all five contacts must be detected as present, control is by serial communication through the data contact with most of the P-TTL functionality being handled by the flash.*


Steve

* The inference is supplied by locus of control for most features being in the flash interface, support of any number of flash models with different output specifications with no apparently lookup tables in the camera, and support for any variety of flash models as wireless P-TTL slaves, each capable of being configured for different outputs. I might also note that the "Type" specification for my Sigma EF-610 DG Super reads, "clip-on type serial-controlled TTL auto zoom electric flash".

[kaseki]

Thanks yet again.

According to page 61 of the AF-540FGZ Operating Manual, when used with the 645N the result is TTL. The 645N is a film camera, and presumably doesn't qualify as digital although it is clearly doing digital stuff in order to display what it does. To confirm what is going on, I think I could take my 645N and AF-540FGZ, connect them together by a 5P cable, and use another cable as a split-out where I could monitor the mode pin with a 'scope. This would likely require at least 3-arms to execute unless I built some kind of hot shoe to flying leads adapter. If I think of a scheme that is not more difficult than my curiosity is worth, I'll try it out.

[stevebrot]

The 645N is a film camera, and presumably doesn't qualify as digital although it is clearly doing digital stuff in order to display what it does. To confirm what is going on

Yes! By digital protocol, I meant digital as in how the flash is controlled, not the capture medium. Almost all digital protocol Pentax cameras are film cameras. The 645N supports digital protocol TTL and yes, hooking the pins of a 5P cable to a scope would allow you to monitor the state of the contact circuits. Be aware that the camera also supports "auto" mode on the AF-540FGZ using analog protocol dedication and that the mode contact, being over-loaded function-wise, may show activity that is coincidental to TTL flash.


Steve

P.S. If you have access to AF280T, AF400T, AF200T, or AF220T your 645N supports analog (four-contact) TTL with those flash as well.