[FozzFoster]

Still waiting on a pre-order option. I'll be placing an order as soon as available - along with the battery grip!

[alfa75ts]

Unexpected indeed, in the first K33 video didn't they discuss their need to to reduce the number of old lenses in the marketplace?

[Paul the Sunman]

I find it interesting how long they kept this feature a secret... makes me wonder, what other surprises they have still left to unveil before it launches.

I expect they will keep some surprises for the launch day.

[MMVIII]

The video showed it as a menu feature. (At least I thought I saw it in the video. There was a list of apertures for selection.)

Added:If Pentax is opting to do real time stop-down metering similar to some 70's M42 cameras, it is a really dumb approach. I believe there is a translation error in the article similar to them using the same graphic twice.End, added Once the aperture is known, Av, metered M and X, and TAv are just a matter of the camera calculating shutter speed from the metered EV. Some digital light meters work similarly and is how the existing exposure automation works using e-dial to set the aperture.


Steve

I'm with Serkevan here. When you mount the lens you set the maximum aperture of the manual lens (this might be what you consider the menue action. During shooting you change the aperture with the aperture ring and just tell the camera the setting with dialing in the value with e-dial. This is all information the camera needs to calculate the proper exposure time from the open aperture reading. It is the same as the camera metering wide open and getting the information of the set aperture with the mechanical aperture coupler, which does not exist in KAF4 mount.
That means you use M lenses like you used to in the old days, setting the aperture on the ring (and additionaly dial in the value), simply, manually.

---

Last edited by MMVIII; 12-25-2020 at 02:22 PM.

[Kevin B123]

I'm with Serkevan here. When you mount the lens you set the maximum aperture of the manual lens (this might be what you consider the menue action. During shooting you change the aperture with the aperture ring and just tell the camera the setting with dialing in the value with e-dial.

This means that you can use the AV rear dial as a super quick EV compensation dial, the meter will believe your input.

[MMVIII]

This means that you can use the AV rear dial as a super quick EV compensation dial, the meter will believe your input.

I don't want to claim to know the way it "really" works, but think this is most probable.
If so, then yes, you are right. But you would loose the recording of the proper value in EXIF.

Edit:
After having a closer look at story 8 again this might not be exactly the case. They do explicitly state that it is "designed to automatically perform closed-down metering at the moment of shutter release". However, I would have thought that with the formerly stated procedure this would not have been necessary, but obviously there must be more to that than I know of ��

[Kevin B123]

But you would loose the recording of the proper value in EXIF.

Yes, I didn't think of that. OK, as you were.....

[shyrsio]

Interesting! I wrote about this in a thread about a month ago. lol
Let's hope we wont be let down.

[Serkevan]

I don't want to claim to know the way it "really" works, but think this is most probable.
If so, then yes, you are right. But you would loose the recording of the proper value in EXIF.

Edit:
After having a closer look at story 8 again this might not be exactly the case. They do explicitly state that it is "designed to automatically perform closed-down metering at the moment of shutter release". However, I would have thought that with the formerly stated procedure this would not have been necessary, but obviously there must be more to that than I know of ��

The way I see it from the Albert Siegel's video and the article itself:
-Menu diving to enable the option (much like enabling the aperture ring)
-Now the aperture e-dial is showing a number and not "F---"
-Use e-dial to tell the camera which aperture you'll have in EXIF, use ring for actual aperture setting.
-Press shutter, lens stops down, camera performs metering & adjusts shutter speed/ISO depending on whether it's Av/TAv mode, photo is taken.

So far, I don't think we've seen a way to tell the camera the maximum aperture of the lens; that would involve a return of the coupler as it was before. However, this is still a nice usability boost IMO.

Some technical questions I personally have: Maybe the new 307k pixel RGB sensor is accurate enough for stop-down metering? Also, and as a direct consequence of the previous question... would that bring matrix metering to manual lenses?

[TwoUptons]

The way I see it from the Albert Siegel's video and the article itself:
-Menu diving to enable the option (much like enabling the aperture ring)
-Now the aperture e-dial is showing a number and not "F---"
-Use e-dial to tell the camera which aperture you'll have in EXIF, use ring for actual aperture setting.
-Press shutter, lens stops down, camera performs metering & adjusts shutter speed/ISO depending on whether it's Av/TAv mode, photo is taken.

So far, I don't think we've seen a way to tell the camera the maximum aperture of the lens; that would involve a return of the coupler as it was before. However, this is still a nice usability boost IMO.

Some technical questions I personally have: Maybe the new 307k pixel RGB sensor is accurate enough for stop-down metering? Also, and as a direct consequence of the previous question... would that bring matrix metering to manual lenses?

I guess my understanding was that the f-number it puts in exif is a separate thing from the stop-down metering, and that it was up to the photographer to ensure they match if desired.

For the exif, I thought it was just a place to put in a number, and that there was nothing else really connected to that, so I could dial in f1.4 on my 300mm f4 and tell people I’d scored a rare prototype...

But for the stop-down metering, my understanding was that the camera would wait to set the shutter speed (and iso, depending on the mode) until the shutter was triggered. Then, as the lens is stopped down, the camera would meter and begin the exposure basically at the same time. Exposure would be set by whatever amount of light came through after the lens was stopped down.

But there is (that I’m aware of) nothing that connects the two except active intervention from the photographer.

-Eric

[c.a.m]

The way I see it from the Albert Siegel's video and the article itself:
-Menu diving to enable the option (much like enabling the aperture ring)
-Now the aperture e-dial is showing a number and not "F---"
-Use e-dial to tell the camera which aperture you'll have in EXIF, use ring for actual aperture setting.
-Press shutter, lens stops down, camera performs metering & adjusts shutter speed/ISO depending on whether it's Av/TAv mode, photo is taken.

This is how I am thinking the exposure system works in the Av and TAv modes, based on what I have seen so far. A blinking 'F' in the display prompts the user to enter the aperture value.

However, in Av mode, the shutter speed would be determined only at the time of exposure, and would not be apparent to the photographer until after the shot has been taken. Not knowing one of the primary exposure elements prior to pressing the shutter button would seem to be inelegant in cases when the photographer's choice of aperture leads to an inappropriate shutter speed. Am I missing a key point here?

- Craig

[Not a Number]

But from what I understand, they didn't add the old aperture coupler back. Instead, they stop down the lens, then take a metering reading, compute the exposure parameters and only then the actual exposure happens.
"Designed to automatically perform closed-down metering at the moment of shutter release, the PENTAX K-3 Mark III also provides automatic exposure setting in the Av and TAv modes while the photographer sets the desired aperture using the lens aperture ring."
It's doing the same thing as the green button did, except right before the exposure.

That's how I'm reading it. The aperture will now close with K and M lenses in Av and TAv mode but you still have to set the aperture ring use the green button to take a meter reading first (as you would in M mode). When the record aperture function it set you can choose what aperture is to be recorded in the EXIF with an eDial. This data is totally independent to what is actually set on the aperture ring as there is still no linkage from the lens to the camera body as to what the lens is set to. So you could have the lens ring set to f2.8 and the camera dial set to f16. When you take the shot the lens will stop down to what is set on the ring - f2.8 in this example.

Without setting the min and max apertures into the camera there would be no way for the body to proportionally move the stop down lever to within a reasonably close position for an f-stop setting. If the intent were to make an M or K lens behave as an "A" lens you would set the ring to the smallest aperture on the lens.

And is there not a non-linear relationship between the movement of the the lever and f-stop change on M and K lenses? So say moving the lever 1mm might result in 1 f-stop change but moving it another 1mm might cause a change of 2 f-stops? M and K lenses don't "care" how far the lever moves as long as it moves far enough for the aperture to close down as the limiter in the lens ring keeps the aperture from closing beyond the set f-stop.

So it seems to me an extra step. Set f-stop on aperture ring. * Set f-stop value on eDial. Press green button. Press shutter.

* "extra" step

[Serkevan]

This is how I am thinking the exposure system works in the Av and TAv modes, based on what I have seen so far. A blinking 'F' in the display prompts the user to enter the aperture value.

However, in Av mode, the shutter speed would be determined only at the time of exposure, and would not be apparent to the photographer until after the shot has been taken. Not knowing one of the primary exposure elements prior to pressing the shutter button would seem to be inelegant in cases when the photographer's choice of aperture leads to an inappropriate shutter speed. Am I missing a key point here?

- Craig

No, that's how I understand it as well. You won't know what shutter speed/ISO (Av and TAv respectively) until the shot is taken. Assuming it works the way I think it works, of course.

[pschlute]

Not really - the way they wrote it, the e-dial used for aperture works normally now. It just doesn't affect operation of the lens itself. So you set up the real aperture on the lens ring, you use the aperture dial to record aperture, and click away. No menu diving the way I understood it.

That was my understanding too from the video. You set the menu up to allow recording of f-stop in the exif, and every time you mount a manual lens the rear wheel can be used to set that record. Note how the "F" of the rear screen flashes to warn you that you are not changing the aperture itself, just the exif record.

[DWS1]

Interesting.