S5ii Electronic First Curtain Shutter

[Oíche]

I seemingly cannot get this to work no matter what settings I chose and reading the sections in the manual. I can feel the click at the start and the click from the rear curtain. It's also not the most subtle shutter either.

The purpose of EFCS is: "The electronic front curtain type reduces blur caused by the shutter because the amount of vibration from the shutter is small compared to the mechanical shutter type."

From the manual it states "mechanical shutter sound" but I can feel the curtain opening. The same occurs whilst using shutter delay.



"When using APS-C lenses, the electronic front curtain is not available." I am using 24-105 f4 and this has me flummoxed.

Quickly comparing EFCS to MECH the dual-pulse shock at exposure beginning is a lot quicker and lighter... But there is something mechanical still operating. Full ES has zero feel with or without a beep of your choice. I am confused as EFCS should surely be the same as ES followed with the mechanical click of the rear curtain.

I've always put importance on reducing mirror and shutter slap/shake/shock buying a huge heavy (for damping) Arca Swiss monoball for SLR/DSLR for the sharpest possible landscapes (especially long telephoto) back in the day.

 

[pdk42]

Are you sure what you’re hearing is the first curtain? Is the sound different between EFCS and mechanical?

Remember that the shutter needs to go through a reset cycle to be back at live view (open).

 

[pdk42]

The sequence of mech shutter should be:

- Bottom curtain rises to blank sensor.
- Charge wells are cleared down.
- Bottom curtain drops.
- Exposure begins.
- Top curtain drops.
- Exposure ends and charge wells are read.
- Both curtains rise (shutter closed) to top.
- Bottom curtain drops and live view restarts.

With EFCS, it’s:

- Charge wells are cleared down.
- Exposure starts electronically.
- Top curtain drops.
- Exposure ends and charge wells are read.
- Both curtains rise (shutter closed) to top.
- Bottom curtain drops and live view restarts

There’s still a lot of curtain movement even with EFCS.

 

[pdk42]

To fully test, do a long exposure with the lens off and you’ll see if there is activity before the exposure time.

 

[Oíche]

Are you sure what you’re hearing is the first curtain? Is the sound different between EFCS and mechanical?

100% I could video it and record it. Yes different sound and feel as previously descibed and still feel shutter shock on shutter opening when there shouldn't be although less so tham full mech shutter mode. Try it for yourself using 0.5 or 1sec etc. so you can definitely hear and feel it. I know you don't have S5ii any longer but the other ones.

Remember that the shutter needs to go through a reset cycle to be back at live view (open).

It is already open hence the EVF/LV feed so why should it have to close and open again? Literature suggests the same? Definitely some movement going on in EFCS except quicker and quieter as previously described. Rear curtain as normal as with mech shutter mode.

 

[pdk42]

100% I could video it and record it. Yes different sound and feel as previously descibed and still feel shutter shock on shutter opening when there shouldn't be although less so tham full mech shutter mode. Try it for yourself using 0.5 or 1sec etc. so you can definitely hear and feel it. I know you don't have S5ii any longer but the other ones.

It is already open hence the EVF/LV feed so why should it have to close and open again? Literature suggests the same? Definitely some movement going on in EFCS except quicker and quieter as previously described. Rear curtain as normal as with mech shutter mode.

Hmm, yes, I see what you mean. I set a 1s exposure and there is shutter movement before and after the 1s exposure, even in EFCS mode. Not what I was expecting - I thought there would be no shutter movement before the exposure. Does it on the S5 and the S1.

I took a video of the standard mech shutter:



You can see this sequence fairly clearly (I got it wrong on the original post):

- Bottom curtain rises (to blank sensor)
[- Charge wells are cleared down.]
- Bottom curtain drops.
[- Exposure begins.]
- Top curtain drops.
[- Exposure ends and charge wells are read.]
- Top curtain rises to top.
[- Live view restarts.]

I can't video EFCS since that's not an option without a supported lens mounted.

Anyone know what's going on?

 

[Oíche]

Thanks for doing the slo-mo video, phones are very useful.

Yes it would be good to see EFCS without lens, there definitely is movement which is not supposed to happen and do they not want us seeing this? Maybe if one took out all the lens elements to see? But do we need to see as I can still feel the first curtain operating but not as shocking, what else could it be?

This is why I was referring to shutter shock to you in another post. Full ES can be used for zero curtain movement say for a still landscape where rolling shutter is irrelevant but then doesn't the bit rate drop?

This is a bit of a quandary, seeing inside during supposed EFCS can certify what is happening, if the first curtain is still being employed then why as it is completely unnecessary and introduces vibration, less than mech first curtain mode but still there.

It's a pity we can't contact Panasonic and ask one of the engineers, maybe Sean Robinson but I doubt he knows either and he doesn't post here. He visited dpreview a few times in the past but never regular to be of much help.

 

[CharlesH]

Full ES can be used for zero curtain movement say for a still landscape where rolling shutter is irrelevant but then doesn't the bit rate drop?

The bit rate only drops (to 12 bit) with high FPS and electronic shutter. It doesn't drop in the single photo mode with electronic shutter, like a landscape.

I've also been wondering about the S1Rii. Will the bit rate drop with high FPS and ES? My experience with the S9 is this isn't the end of the world with action shots, but of course one would rather have 14 bits.

There is some strange language in the specs just released in the L-Mount rumor site that I don't understand. "SRGB, AdobeRGB / 14 stops (V-Log) (Dynamic Range Expansion (Log) ON" . It is almost like they might be extending photo dynamic range by using the V-Log format. This, of course, is how you get by shooting video with just 10 bits and still have full dynamic range. It would be clever if they have done something like this for photo.

 

[pdk42]

There is some strange language in the specs just released in the L-Mount rumor site that I don't understand. "SRGB, AdobeRGB / 14 stops (V-Log) (Dynamic Range Expansion (Log) ON" . It is almost like they might be extending photo dynamic range by using the V-Log format. This, of course, is how you get by shooting video with just 10 bits and still have full dynamic range. It would be clever if they have done something like this for photo.

My understanding is that vLog etc are all "JPEG" modes - that is, processed images after de-mosaicing, tone curve etc. Raw files will presumably still be raw and unprocessed (mostly!).

 

[CharlesH]

My understanding is that vLog etc are all "JPEG" modes - that is, processed images after de-mosaicing, tone curve etc. Raw files will presumably still be raw and unprocessed (mostly!).

For video, VLog can be either way, processed or RAW. That is, ProRes RAW is usually done with VLog. If they were to somehow apply a log function to photos I have no ideal how that would happen, but I wouldn't rule out RAW.

 

[pdk42]

Thanks for doing the slo-mo video, phones are very useful.

Yes it would be good to see EFCS without lens, there definitely is movement which is not supposed to happen and do they not want us seeing this? Maybe if one took out all the lens elements to see? But do we need to see as I can still feel the first curtain operating but not as shocking, what else could it be?

This is why I was referring to shutter shock to you in another post. Full ES can be used for zero curtain movement say for a still landscape where rolling shutter is irrelevant but then doesn't the bit rate drop?

This is a bit of a quandary, seeing inside during supposed EFCS can certify what is happening, if the first curtain is still being employed then why as it is completely unnecessary and introduces vibration, less than mech first curtain mode but still there.

It's a pity we can't contact Panasonic and ask one of the engineers, maybe Sean Robinson but I doubt he knows either and he doesn't post here. He visited dpreview a few times in the past but never regular to be of much help.

I have a lot of experience with shutter shock from my days as an Olympus user. Most of their m43 cameras up to the EM1 mark ii suffered to some degree from it. Some cameras, like the E-P5, were really bad. Olympus, to their credit, eventually released a firmware kludge that fixed it. They called it "zero seconds" delay. This is the story:

- The shutter they used in these earlier cameras had a fixed operation cycle that was part of its mechanical design.

- The sequence was always:
1) lift bottom curtain (ends live view, sensor wells get cleared)
2) drop bottom curtain (start exposure)
3) drop top curtain (end exposure)
4) lift top curtain (re-start live view).

- Shutter shock happened because the bottom curtain movement in step (2) caused "ringing" in the sensor mechanism (IBIS etc) that took about 20ms to subside (basically, the bottom curtain crashed into its base and there was insufficient damping). For exposures much longer or shorter than 20ms it didn't cause any noticeable effect, but for shutter speeds in the 1/50 to 1/200s range, it caused big problems. The severity depended to some degree on the lens and the way the camera was held/mounted since this would change the damping characteristics of the ringing. But it never totally went away.

- Ideally Olympus would have simply avoided doing steps 1 and 2 by implementing proper EFCS, but the sequence in these earlier cameras was fixed. However they figured out that since the ringing subsided in about 20mS, if they extended the shutter exposure period by that amount and then use an EFCS technique after that then the problem would be fixed. A neat solution!

- So that's what they did. They called it "0s delay", even though it was 20ms! The sequence with this enabled became:
1) lift bottom curtain (ends live view, sensor wells get cleared)
2) drop bottom curtain
3) Wait 20ms for ringing to subside
4) Start exposure using EFCS
5) close top curtain (end exposure)
6) open top curtain (re-start live view).

- In the EM5 mark ii they introduced a new shutter that supported a proper EFCS sequence (so basically doing only a top curtain drop and lift). That worked great in EFCS, but there was still some ringing if you used full mechanical shutter. From the EM1 mark ii they got the damping right and shutter shock even in full mechanical shutter ceased to be a problem.

You can see that I spent some time getting my head around all of this - and that's why I stated so confidently that EFCS doesn't do any shutter movement before the exposure. Do a 1s exposure on an Olympus/OM camera with EFCS enabled and you'll hear nothing until after the 1s has expired.

So, I was really surprised to hear my Panasonic cameras moving the shutter before the exposure with EFCS enabled. And in fact, by peering through the 50mm f1.8 lens at the right angle, I can see it too.

I'm very confused now as to what is happening - BUT MAYBE PANASONIC ARE USING THE SAME TRICK AS OLYMPUS. That is, there is a delay after the bottom curtain drops that allows any ringing to subside and then they start the EFCS. I really can't think of any other explanation.

 

[pdk42]

For video, VLog can be either way, processed or RAW. That is, ProRes RAW is usually done with VLog. If they were to somehow apply a log function to photos I have no ideal how that would happen, but I wouldn't rule out RAW.

But surely video can never be truly raw - since that would mean every frame would need post-processing to demosaic the data, add a tone curve, sharpening etc. Surely no PC without dedicated DSP could ever do that quickly enough?

 

[pdk42]

Old thread on the same subject here:

https://www.dpreview.com/forums/post/67269131

 

[Oíche]

And in fact, by peering through the 50mm f1.8 lens at the right angle, I can see it too.

Well done, I was going to attempt it using a torch but you've confirmed what I felt.

"0ms delay" oxymoronic.

Is Panasonic telling fibs or what over EFCS? The manual suggests so!

As I previously mentioned though the first curtain sound is faster opening and closing and with lesser shock in EFCS mode compared to MECH mode. I suppose a slo-mo could illustrate the sound part and a mini seismometer to prove what I feel in my hands

I'm happy to use full ES if no bit-rate reduction is used for single exposure but maybe they implement some method as you suggest and there is no sensor shake even if you can feel it through the camera body. I have the shutter selection in my Quick Menu button, I'm learning this camera at snail's pace.

Good enjoyable tech post

 

[CharlesH]

But surely video can never be truly raw - since that would mean every frame would need post-processing to demosaic the data, add a tone curve, sharpening etc. Surely no PC without dedicated DSP could ever do that quickly enough?

ProRes RAW is sort of processed out of the camera, partially processed, but no sharpening or noise reduction, and no lens correction. You need to add these things with the video editor, and of course modify the tone curve as needed. You do want a capable computer for this.

 

[Oíche]

You do want a capable computer for this.

Apple Silicon have dedicated ProRes hardware processing, even the later phones I think. PC hardware is going to need general CPU to do the same task.

Can't ever see myself ever wanting ProRes and definitely not Paul. I'm delighted with MOV 4k 50p 4.2.2 and standard colour profile as it looks exactly like reality but I'm no video buff like yourself.

 

[pdk42]

Is Panasonic telling fibs or what over EFCS? The manual suggests so!

Interestingly, if you read what the manual actually says, there is wriggle room for EFCS to actually be the same sort of kludge that Olympus did:



Note it says "small", not "none". And...



There is no contradiction between "This type starts exposure electronically" and the 0s kludge.

 

[pdk42]

And this article :

https://www.panasonic.com/uk/consumer/cameras-camcorders/lumix-expert-advice-learn/technique-technology/electronic-vs-mechanical-shutter-modes.html

says this:



Again, no contradiction between this and the implementation using the 0s approach that Olympus uses.

 

[pdk42]

To prove my hypothesis we need an experiment that can fire the shutter at a known time while photographing a clock with milliisecond precision. If EFCS is using the 0s approach then there will a longer delay between firing the shutter and taking the shot in EFCS mode. Using the Lumix Sync app an iPad might do the trick if we can also show a counter running at the same time - does split screen support this?

 

[pdk42]

To prove my hypothesis we need an experiment that can fire the shutter at a known time while photographing a clock with milliisecond precision. If EFCS is using the 0s approach then there will a longer delay between firing the shutter and taking the shot in EFCS mode. Using the Lumix Sync app an iPad might do the trick if we can also show a counter running at the same time - does split screen support this?

LUMIX Sync doesn’t support split screen on an iPad