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WAHOO 203FE back from overseas With CFV ability now
- Thread starter fotografz
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Hi Q.G.,
> "and we know the shutter trigger is hooked up to the CPU" > > No. We do not (!) know that.
"WE" may not, but I absolutely do! Again, if you had one of these cameras, you would be able to experiment for your self and see.
There are three positions for the shutter release. Not pressed, half way pressed, and fully pressed. If I put the mode selector in "Pr" it displays "Pr 10s". When depressing the shutter button half way, the display changes to displaying the aperture setting and the shutter speed. While in this half way position, when moving the camera around to varying lighting conditions, the shutter speed changes in the display. When the shutter button is fully pressed, it locks the shutter speed so it does not change, and it does not change when moving the camera around to varying lighting conditions.
Clearly three distinct display condition, each based on one of the three positions of the shutter release. The display is unquestionably controlled by the CPU, so the shutter release is unquestionably "hooked up" to the CPU.
Regards,
Austin
> "and we know the shutter trigger is hooked up to the CPU" > > No. We do not (!) know that.
"WE" may not, but I absolutely do! Again, if you had one of these cameras, you would be able to experiment for your self and see.
There are three positions for the shutter release. Not pressed, half way pressed, and fully pressed. If I put the mode selector in "Pr" it displays "Pr 10s". When depressing the shutter button half way, the display changes to displaying the aperture setting and the shutter speed. While in this half way position, when moving the camera around to varying lighting conditions, the shutter speed changes in the display. When the shutter button is fully pressed, it locks the shutter speed so it does not change, and it does not change when moving the camera around to varying lighting conditions.
Clearly three distinct display condition, each based on one of the three positions of the shutter release. The display is unquestionably controlled by the CPU, so the shutter release is unquestionably "hooked up" to the CPU.
Regards,
Austin
Hi Timothy,
> My god, guys! Give it a rest. My inbox begs you.
Ha ha...once Q.G. says "uncle" ;-)
But, seriously, I think we're almost at an end. I've substantiated the interface works as I said it does from stem to stern...and the only thing left is getting the schematics. Which, of course, would be wonderful if we could.
Regards,
Austin
> My god, guys! Give it a rest. My inbox begs you.
Ha ha...once Q.G. says "uncle" ;-)
But, seriously, I think we're almost at an end. I've substantiated the interface works as I said it does from stem to stern...and the only thing left is getting the schematics. Which, of course, would be wonderful if we could.
Regards,
Austin
Hi Q.G.,
> What does the display do when you prerelease the camera?
When you press the pre-release, the display goes to the state where the shutter release is depressed half-way. When you unpress the pre-release, the display goes back to the state where the shutter release is not pressed.
I believe it's also reasonable to conclude that the self timer is controlled by the CPU.
As a note, the 205 service manual gives some more clues. On p. 3:5, they talk about being able to release the magnets on the main circuit board:
"The magnets can be released from the main circuit board when troubleshooting."
I think it's also reasonable to conclude that these are the shutter release magnets. One for first curtain, and one for second curtain. If you look at the picture of the "magnet" assembly shown on p. 3:5, and go to p. 17, you'll see two of those devices shown, one above each of the shutter gears. They are not listed as spare parts in the parts list (no designation number for this assembly is given), as it states on p. 3:5.
So, we know these magnets can be released from the circuit board, and if they are in fact the shutter release magnets (which they appear to be), they are controlled electronically on the main circuit board. They are also going to be electromagnets, not simply magnets.
One other interesting note in the service manual on p. 1:1:
"Electronically controlled mechanical focal plane shutter with (203FE/205FCC) release solenoid system."
As we know, solenoids are electromagnetic devices...so perhaps this was just a "confusing" translation.
See p. 19 as well. I think the circuit board they show is the one that interfaces to the shutter release button, and some other mechanical I/O. One they call the "sync switch assembly" (#8), and another the "late release switch" (#4), but it's the one that has no designation and has four numbered wires going to it that I'm interested in. It almost looks like it could be a pair of electromagnets...that could coinside with the assembly referenced above.
Regards,
Austin
> What does the display do when you prerelease the camera?
When you press the pre-release, the display goes to the state where the shutter release is depressed half-way. When you unpress the pre-release, the display goes back to the state where the shutter release is not pressed.
I believe it's also reasonable to conclude that the self timer is controlled by the CPU.
As a note, the 205 service manual gives some more clues. On p. 3:5, they talk about being able to release the magnets on the main circuit board:
"The magnets can be released from the main circuit board when troubleshooting."
I think it's also reasonable to conclude that these are the shutter release magnets. One for first curtain, and one for second curtain. If you look at the picture of the "magnet" assembly shown on p. 3:5, and go to p. 17, you'll see two of those devices shown, one above each of the shutter gears. They are not listed as spare parts in the parts list (no designation number for this assembly is given), as it states on p. 3:5.
So, we know these magnets can be released from the circuit board, and if they are in fact the shutter release magnets (which they appear to be), they are controlled electronically on the main circuit board. They are also going to be electromagnets, not simply magnets.
One other interesting note in the service manual on p. 1:1:
"Electronically controlled mechanical focal plane shutter with (203FE/205FCC) release solenoid system."
As we know, solenoids are electromagnetic devices...so perhaps this was just a "confusing" translation.
See p. 19 as well. I think the circuit board they show is the one that interfaces to the shutter release button, and some other mechanical I/O. One they call the "sync switch assembly" (#8), and another the "late release switch" (#4), but it's the one that has no designation and has four numbered wires going to it that I'm interested in. It almost looks like it could be a pair of electromagnets...that could coinside with the assembly referenced above.
Regards,
Austin
Hello Austin,
I agree that the display may hold the clue.
The 2000-series cameras have the same mix of electric and mechanical bits involved in the release mechanism and procedure. The magnets mentioned are what 'the mechanical guys' contributed, helping the thing along again.
They (the magnets) in the 2000-series can be released from the circuit board too, and these cameras do not have a CPU.
So i don't think this in particular tells us much.
(Hasselblad once 'invented' a remote release cord for the 2000 FC. It plugged into the battery box, and released the camera 'from the circuit board'. It never made it to the shops, since there was no way to reset the camera and wind film remotely too.
)
The 'late' and 'early' switches, by the way, have to do with 'C' and 'F' modes.
I agree that the display may hold the clue.
The 2000-series cameras have the same mix of electric and mechanical bits involved in the release mechanism and procedure. The magnets mentioned are what 'the mechanical guys' contributed, helping the thing along again.
They (the magnets) in the 2000-series can be released from the circuit board too, and these cameras do not have a CPU.
So i don't think this in particular tells us much.
(Hasselblad once 'invented' a remote release cord for the 2000 FC. It plugged into the battery box, and released the camera 'from the circuit board'. It never made it to the shops, since there was no way to reset the camera and wind film remotely too.
The 'late' and 'early' switches, by the way, have to do with 'C' and 'F' modes.
Hi Q.G.,
> The 2000-series cameras have the same mix of electric and mechanical > bits involved in the release mechanism and procedure. >... > They (the magnets) in the 2000-series can be released from the circuit > board too, and these cameras do not have a CPU. > So i don't think this in particular tells us much.
I think it tells us a lot. The timing of the shutter is done by some electronics in each camera, we know and agree on that. In the 2000 series it is by analog control (we know and agree on that), and in the 20x, it is done under digital control. We know that is so in the 20x, since it is verly clearly stated in the brochure (and through use) that the metering can control the shutter, and the CPU is what determines the metering. And, the CPU is digital... So though we apparently don't agree on this entirely, I think, again, the documentation and operation bares this out.
How, exactly, do you believe it works from the shutter button to the shutter release?
> The 'late' and 'early' switches, by the way, have to do with 'C' and > 'F' modes.
I hadn't associated those, thanks.
Regards,
Austin
> The 2000-series cameras have the same mix of electric and mechanical > bits involved in the release mechanism and procedure. >... > They (the magnets) in the 2000-series can be released from the circuit > board too, and these cameras do not have a CPU. > So i don't think this in particular tells us much.
I think it tells us a lot. The timing of the shutter is done by some electronics in each camera, we know and agree on that. In the 2000 series it is by analog control (we know and agree on that), and in the 20x, it is done under digital control. We know that is so in the 20x, since it is verly clearly stated in the brochure (and through use) that the metering can control the shutter, and the CPU is what determines the metering. And, the CPU is digital... So though we apparently don't agree on this entirely, I think, again, the documentation and operation bares this out.
How, exactly, do you believe it works from the shutter button to the shutter release?
> The 'late' and 'early' switches, by the way, have to do with 'C' and > 'F' modes.
I hadn't associated those, thanks.
Regards,
Austin
Hi Q.G.,
> I agree that the display may hold the clue.
The display tells us that the shutter release button state is known by the CPU, which is one of the things you were questioning. I believe this is not questionable now, given the evidence.
In my book, the only remaining question is, and it's kind of two-fold...does the CPU actually trip the shutter, or is it done electro-mechanically. And, if not, what is the timing relationship between the CPU knowing the shutter is tripped and the shutter actually tripping.
The easiest and most accurate way to operate a shutter if you have a CPU in the device already...is to take the shutter button as an input to the CPU, and since the CPU knows the shutter speed, it would output a release of the first magnet, therefore tripping the first shutter curtain...and then, after the appropriate shutter time, release the second magnet, therefore tripping the second shutter curtain.
The CPU has to have a clock, that is part and parcel of how it operates, and 1/2000 is very slow in CPU time. It is only 500 microseconds. Even a really slow CPU, say at 1MHz, or 1 microsecond per cycle, would easily be able to handle timing 500 microseconds, either by using a built-in timer (which most have) or by simply counting. This is very easy to do. The CPU is doing nothing else during this time anyway, so even if it was a dedicated timing loop, no other operation would be effected.
Regards,
Austin
> I agree that the display may hold the clue.
The display tells us that the shutter release button state is known by the CPU, which is one of the things you were questioning. I believe this is not questionable now, given the evidence.
In my book, the only remaining question is, and it's kind of two-fold...does the CPU actually trip the shutter, or is it done electro-mechanically. And, if not, what is the timing relationship between the CPU knowing the shutter is tripped and the shutter actually tripping.
The easiest and most accurate way to operate a shutter if you have a CPU in the device already...is to take the shutter button as an input to the CPU, and since the CPU knows the shutter speed, it would output a release of the first magnet, therefore tripping the first shutter curtain...and then, after the appropriate shutter time, release the second magnet, therefore tripping the second shutter curtain.
The CPU has to have a clock, that is part and parcel of how it operates, and 1/2000 is very slow in CPU time. It is only 500 microseconds. Even a really slow CPU, say at 1MHz, or 1 microsecond per cycle, would easily be able to handle timing 500 microseconds, either by using a built-in timer (which most have) or by simply counting. This is very easy to do. The CPU is doing nothing else during this time anyway, so even if it was a dedicated timing loop, no other operation would be effected.
Regards,
Austin
"The display tells us that the shutter release button state is known by the CPU, which is one of the things you were questioning."
I wasn't.
I was (still am) wondering whether the controller knows the shutter is open.
And that's not splitting hairs, it's not the same. You can - as every 500-series knows - let go of it before the shutter has closed. Or keep the release button depressed long after the shutter has closed again.
That's why the behaviour of the display relative to the position of the release button might hold a clue, but is not proof.
The answer to one of the two parts of your remaining question: the shutter is tripped by mechanical bits. That's why it still works in C mode even when there is no power.
The timing of the shutter is done by the electrical bits.
But whether that means it is done by the controller, or (like in the 2000) by some other bit?
The speeds are adjusted using a potentiometer. Could indicate that some means are necessary to adjust the other electro(-mechanical) bits to keep up with the controller's precision. Or that the timing is not done by a CPU.
I wasn't.
I was (still am) wondering whether the controller knows the shutter is open.
And that's not splitting hairs, it's not the same. You can - as every 500-series knows - let go of it before the shutter has closed. Or keep the release button depressed long after the shutter has closed again.
That's why the behaviour of the display relative to the position of the release button might hold a clue, but is not proof.
The answer to one of the two parts of your remaining question: the shutter is tripped by mechanical bits. That's why it still works in C mode even when there is no power.
The timing of the shutter is done by the electrical bits.
But whether that means it is done by the controller, or (like in the 2000) by some other bit?
The speeds are adjusted using a potentiometer. Could indicate that some means are necessary to adjust the other electro(-mechanical) bits to keep up with the controller's precision. Or that the timing is not done by a CPU.
Hi Q.G.,
> "The display tells us that the shutter release button state is known > by the CPU, which is one of the things you were questioning." > > I wasn't. > I was (still am) wondering whether the controller knows the shutter is > open. > And that's not splitting hairs, it's not the same. You can - as every > 500-series knows - let go of it before the shutter has closed.
It only needs to know when it's released, so it can send that to the back.
But, it does in fact know when it's open, if it knows when it's released. The CPU knows the shutter speed, and knowing when the shutter first opens, it can simply count from there. So, that is not an issue.
> The answer to one of the two parts of your remaining question: the > shutter is tripped by mechanical bits.
The shutter curtains do obviously open and close, like the barn doors on the 500 do, when in C mode, but there is no shutter timing circuitry per se. But, that does not mean that when not in C mode, they are not tripped fully electronically. That conclusion can't be drawn from any of the information we have to date as far as I can tell.
> The speeds are adjusted using a potentiometer.
From what I can tell, only one speed...1/2000...is adjusted by a pot. At least that is what the service manual says. But, that is no indication as to how the timing is done. It can simply be adjusting a time base. But, this seems strange to me...since if you have an oscillator for a microprocessor, it is handily well within any tolerance needed to accurately produce 1/2000.
But, to go back to the initial supposition...all the CPU needs to know is when the shutter release is fully pressed, it doesn't matter how long it's pressed for. And we know that the CPU does know when the shutter release is fully pressed (to trigger the shutter). Whether the timing is "correct" is another issue.
Regards,
Austin
> "The display tells us that the shutter release button state is known > by the CPU, which is one of the things you were questioning." > > I wasn't. > I was (still am) wondering whether the controller knows the shutter is > open. > And that's not splitting hairs, it's not the same. You can - as every > 500-series knows - let go of it before the shutter has closed.
It only needs to know when it's released, so it can send that to the back.
But, it does in fact know when it's open, if it knows when it's released. The CPU knows the shutter speed, and knowing when the shutter first opens, it can simply count from there. So, that is not an issue.
> The answer to one of the two parts of your remaining question: the > shutter is tripped by mechanical bits.
The shutter curtains do obviously open and close, like the barn doors on the 500 do, when in C mode, but there is no shutter timing circuitry per se. But, that does not mean that when not in C mode, they are not tripped fully electronically. That conclusion can't be drawn from any of the information we have to date as far as I can tell.
> The speeds are adjusted using a potentiometer.
From what I can tell, only one speed...1/2000...is adjusted by a pot. At least that is what the service manual says. But, that is no indication as to how the timing is done. It can simply be adjusting a time base. But, this seems strange to me...since if you have an oscillator for a microprocessor, it is handily well within any tolerance needed to accurately produce 1/2000.
But, to go back to the initial supposition...all the CPU needs to know is when the shutter release is fully pressed, it doesn't matter how long it's pressed for. And we know that the CPU does know when the shutter release is fully pressed (to trigger the shutter). Whether the timing is "correct" is another issue.
Regards,
Austin