What else is happening before the first curtain on E-M1?

Started 5 months ago | Discussions
Jim Salvas
Senior MemberPosts: 2,648Gear list
Like?
What else is happening before the first curtain on E-M1?
5 months ago

With the new update installed and the electronic first curtain shutter option enabled, there is clearly a click before the exposure. It's easy to hear at 1/4 second and something is visibly moving very fast if you're brave enough to fire it off with the lens removed and watch what happens.

What is that?

-- hide signature --

Jim Salvas

 Jim Salvas's gear list:Jim Salvas's gear list
Olympus PEN E-PM2 Olympus E-M1 Panasonic Lumix DMC-GH4 Olympus M.Zuiko Digital 14-42mm 1:3.5-5.6 II R Olympus M.Zuiko Digital ED 40-150mm 1:4-5.6 R +8 more
Olympus E-M1
If you believe there are incorrect tags, please send us this post using our feedback form.
Jim Salvas
Senior MemberPosts: 2,648Gear list
Like?
Re: What else is happening before the first curtain on E-M1?
In reply to Jim Salvas, 5 months ago

I'm adding to this because in another thread, AndersW suggested it may be the shutter cocking. I've tried it both with short and normal release lag time and it still happens.

Can anyone confirm or figure out what else is going on?

-- hide signature --

Jim Salvas

 Jim Salvas's gear list:Jim Salvas's gear list
Olympus PEN E-PM2 Olympus E-M1 Panasonic Lumix DMC-GH4 Olympus M.Zuiko Digital 14-42mm 1:3.5-5.6 II R Olympus M.Zuiko Digital ED 40-150mm 1:4-5.6 R +8 more
Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 17,343Gear list
Like?
Re: What else is happening before the first curtain on E-M1?
In reply to Jim Salvas, 5 months ago

Jim Salvas wrote:

With the new update installed and the electronic first curtain shutter option enabled, there is clearly a click before the exposure. It's easy to hear at 1/4 second and something is visibly moving very fast if you're brave enough to fire it off with the lens removed and watch what happens.

What is that?

Jim,

Did you verify that the EFCS stays enabled (based on what the camera is telling you) when you remove the lens? One question we were pondering in the other thread was whether EFCS would be allowed/would work with a lens that is not electrically connected to the body. It may be that the EFCS needs/wants information from the lens in order to sync properly with the second curtain, or rather the shadow of the second curtain, which will vary with the lens, FL, and f-stop used.

As to the thing you see moving, does it look like it's shutter blades blocking the sensor or something else? What about shooting a video of the sequence with another camera and play it back frame by frame?

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
kenw
Veteran MemberPosts: 4,238Gear list
Like?
Re: What else is happening before the first curtain on E-M1?
In reply to Anders W, 5 months ago

Anders W wrote:

Did you verify that the EFCS stays enabled (based on what the camera is telling you) when you remove the lens? One question we were pondering in the other thread was whether EFCS would be allowed/would work with a lens that is not electrically connected to the body. It may be that the EFCS needs/wants information from the lens in order to sync properly with the second curtain, or rather the shadow of the second curtain, which will vary with the lens, FL, and f-stop used.

As a related side note the GM1 has EFCS and electronic rolling as the only two options. When you put a manual lens on (no electronics) it always uses electronic rolling unless you are using flash.

That would seem to match your stated theory about EFCS syncing and lens characteristics.

That said, it seems the EM1 only uses EFCS slower than 1/320 to begin with and I have trouble imagining the exit pupil location and size would really make a difference at what is effectively already the flash sync speed. I mean what will that be, 1/10th a stop variation?

-- hide signature --

Ken W
See profile for equipment list

 kenw's gear list:kenw's gear list
Sony RX100 Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Panasonic Lumix DMC-GM1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS +26 more
Reply   Reply with quote   Complain
Jim Salvas
Senior MemberPosts: 2,648Gear list
Like?
Re: What else is happening before the first curtain on E-M1?
In reply to Anders W, 5 months ago

Anders W wrote:

Jim Salvas wrote:

With the new update installed and the electronic first curtain shutter option enabled, there is clearly a click before the exposure. It's easy to hear at 1/4 second and something is visibly moving very fast if you're brave enough to fire it off with the lens removed and watch what happens.

What is that?

Jim,

Did you verify that the EFCS stays enabled (based on what the camera is telling you) when you remove the lens? One question we were pondering in the other thread was whether EFCS would be allowed/would work with a lens that is not electrically connected to the body. It may be that the EFCS needs/wants information from the lens in order to sync properly with the second curtain, or rather the shadow of the second curtain, which will vary with the lens, FL, and f-stop used.

As to the thing you see moving, does it look like it's shutter blades blocking the sensor or something else? What about shooting a video of the sequence with another camera and play it back frame by frame?

I seem to get the same sounds with the lens on or off. Of course, the intensity of the sounds is different when removed, but the sequence seems to sound the same.

Looking into the sensor, I can see something wink across it just before the exposure, but it does not seem to be a shutter blade. The shutter curtain is actually pretty far forward from the sensor and this -- whatever it is -- seems to be almost on the sensor.

I thought it might also be an optical illusion caused by movement of the sensor as IS kicked in, but it's the same with or without IS.

Next step might be high speed photography of this happening. Wish I had that new Olympus compact, with 120fps.

-- hide signature --

Jim Salvas

 Jim Salvas's gear list:Jim Salvas's gear list
Olympus PEN E-PM2 Olympus E-M1 Panasonic Lumix DMC-GH4 Olympus M.Zuiko Digital 14-42mm 1:3.5-5.6 II R Olympus M.Zuiko Digital ED 40-150mm 1:4-5.6 R +8 more
Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 17,343Gear list
Like?
Re: What else is happening before the first curtain on E-M1?
In reply to kenw, 5 months ago

kenw wrote:

Anders W wrote:

Did you verify that the EFCS stays enabled (based on what the camera is telling you) when you remove the lens? One question we were pondering in the other thread was whether EFCS would be allowed/would work with a lens that is not electrically connected to the body. It may be that the EFCS needs/wants information from the lens in order to sync properly with the second curtain, or rather the shadow of the second curtain, which will vary with the lens, FL, and f-stop used.

As a related side note the GM1 has EFCS and electronic rolling as the only two options. When you put a manual lens on (no electronics) it always uses electronic rolling unless you are using flash.

That's very useful info. It suggests that the electrically connected lenses do have information about the parameters the body needs to calculate the movement of the shadow (rather than the curtain itself). With flash, of course, it doesn't matter (or doesn't matter as much) whether the two curtains are in perfect synch or not.

That would seem to match your stated theory about EFCS syncing and lens characteristics.

Yes.

That said, it seems the EM1 only uses EFCS slower than 1/320 to begin with and I have trouble imagining the exit pupil location and size would really make a difference at what is effectively already the flash sync speed. I mean what will that be, 1/10th a stop variation?

Yes, my thoughts parallel yours exactly. It shouldn't make a whole lot of difference at the shutter speeds where the E-M1 uses the EFCS.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
Jim Salvas
Senior MemberPosts: 2,648Gear list
Like?
Another test
In reply to Jim Salvas, 5 months ago

I just shot a video of the action with my PM2. Watching that, it appears the first movement is horizontal across the sensor and the second movement is vertical.

I will edit the clip and post to YouTube.

-- hide signature --

Jim Salvas

 Jim Salvas's gear list:Jim Salvas's gear list
Olympus PEN E-PM2 Olympus E-M1 Panasonic Lumix DMC-GH4 Olympus M.Zuiko Digital 14-42mm 1:3.5-5.6 II R Olympus M.Zuiko Digital ED 40-150mm 1:4-5.6 R +8 more
Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 17,343Gear list
Like?
Re: What else is happening before the first curtain on E-M1?
In reply to Jim Salvas, 5 months ago

Jim Salvas wrote:

Anders W wrote:

Jim Salvas wrote:

With the new update installed and the electronic first curtain shutter option enabled, there is clearly a click before the exposure. It's easy to hear at 1/4 second and something is visibly moving very fast if you're brave enough to fire it off with the lens removed and watch what happens.

What is that?

Jim,

Did you verify that the EFCS stays enabled (based on what the camera is telling you) when you remove the lens? One question we were pondering in the other thread was whether EFCS would be allowed/would work with a lens that is not electrically connected to the body. It may be that the EFCS needs/wants information from the lens in order to sync properly with the second curtain, or rather the shadow of the second curtain, which will vary with the lens, FL, and f-stop used.

As to the thing you see moving, does it look like it's shutter blades blocking the sensor or something else? What about shooting a video of the sequence with another camera and play it back frame by frame?

I seem to get the same sounds with the lens on or off. Of course, the intensity of the sounds is different when removed, but the sequence seems to sound the same.

And the EFCS option is not greyed out or something like that with the lens removed?

Looking into the sensor, I can see something wink across it just before the exposure, but it does not seem to be a shutter blade. The shutter curtain is actually pretty far forward from the sensor and this -- whatever it is -- seems to be almost on the sensor.

I am only guessing here, but it might be something moving to "cock" the second curtain.

I thought it might also be an optical illusion caused by movement of the sensor as IS kicked in, but it's the same with or without IS.

Well that's another possibility that is worth considering. And setting IBIS on versus off doesn't offer a proper test. Even when off, IBIS behaves differently during exposure than before and after exposure. During exposure, regardless of whether IBIS is on or off, it goes into high-power mode (sensor held rigidly). Before and after exposure, it is in low-power mode (lower power consumption, less of the "fanning" noise).

When IBIS is on, it also goes into high-power mode when you half-press the shutter button provided that you have the camera set to stabilize the EVF on half-press. With the camera set to stabilize the EVF, do you see a difference in behavior when looking at shutter action if you half-press, wait a little, and then press fully versus pressing fully in one go?

Next step might be high speed photography of this happening. Wish I had that new Olympus compact, with 120fps.

Yes, it's hard to tell how much of it you can really see with ordinary video.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 17,343Gear list
Like?
Re: Another test
In reply to Jim Salvas, 5 months ago

Jim Salvas wrote:

I just shot a video of the action with my PM2. Watching that, it appears the first movement is horizontal across the sensor and the second movement is vertical.

So at least it's not the shutter blades. Should be either something to do with shutter "cocking" or something to do with IBIS shifting from low-power to high-power mode.

I will edit the clip and post to YouTube.

Yes, please do.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
Jim Salvas
Senior MemberPosts: 2,648Gear list
Like?
Shutter video
In reply to Anders W, 5 months ago

Here is the clip of the shutter action, with Electronic First Curtain enabled.

https://www.youtube.com/watch?v=_xYPien3BGs&feature=youtu.be

-- hide signature --

Jim Salvas

 Jim Salvas's gear list:Jim Salvas's gear list
Olympus PEN E-PM2 Olympus E-M1 Panasonic Lumix DMC-GH4 Olympus M.Zuiko Digital 14-42mm 1:3.5-5.6 II R Olympus M.Zuiko Digital ED 40-150mm 1:4-5.6 R +8 more
Reply   Reply with quote   Complain
Jim Salvas
Senior MemberPosts: 2,648Gear list
Like?
Re: Shutter video
In reply to Jim Salvas, 5 months ago

I just took that clip into iMovie, where I can slow it down to frame by frame. It definitely seems as if the first curtain is closing and then opening again, but it sure is fast. When you listen to it frame by frame, there are quite a few shutter sounds going on.

-- hide signature --

Jim Salvas

 Jim Salvas's gear list:Jim Salvas's gear list
Olympus PEN E-PM2 Olympus E-M1 Panasonic Lumix DMC-GH4 Olympus M.Zuiko Digital 14-42mm 1:3.5-5.6 II R Olympus M.Zuiko Digital ED 40-150mm 1:4-5.6 R +8 more
Reply   Reply with quote   Complain
Guy Parsons
Forum ProPosts: 18,530Gear list
Like?
Need 1,000 fps at least.....
In reply to Anders W, 5 months ago

Anders W wrote:

What about shooting a video of the sequence with another camera and play it back frame by frame?

In the past I've done a 1,000 fps video of the E-PL5 shutter in action, but it definitely needs something better than my Casio ZR1000 to do that as things are still blurred frame by frame.

All I see in normal E-PL5 shutter operation is the shutter closing (with a huge amount of bounce) to darken the sensor and clear it, then the shutter curtains run, then the shutter stays closed for about 1/10 second for the unload time, then back to live view.

http://i100.photobucket.com/albums/m36/photoguy340/dprstuff/epl5shutter2_zps60fc6f28.gif

Very low resolution and slowed down of course in this animated gif (which, darn it, DPReview can't display here like it could before).

If only Olympus would lend me cameras to play with and then I could try E-M1 and E-M10 and see how they operate.....

Regards.... Guy

 Guy Parsons's gear list:Guy Parsons's gear list
Olympus PEN E-PL5 Panasonic Lumix G Vario 45-150mm F4-5.6 ASPH Mega OIS Olympus 12-40mm F2.8 Panasonic Lumix DMC-LX3 Casio Exilim EX-ZR1000 +16 more
Reply   Reply with quote   Complain
simpy
Veteran MemberPosts: 3,087Gear list
Like?
Re: Shutter video
In reply to Jim Salvas, 5 months ago

Jim Salvas wrote:

I just took that clip into iMovie, where I can slow it down to frame by frame. It definitely seems as if the first curtain is closing and then opening again, but it sure is fast. When you listen to it frame by frame, there are quite a few shutter sounds going on.

Could it be that the physical shutter sequence is not altered, but the electronic shutter makes it possible to adjust the timing of the actions?

For example, the initial curtain could close and reopen as quickly as possible, before the camera/sensor is ready to shoot. That might give a few milliseconds for things to settle down before the electronic shutter starts exposure.

 simpy's gear list:simpy's gear list
Olympus E-M1 Olympus M.Zuiko Digital ED 9-18mm 1:4.0-5.6 Olympus Zuiko Digital 11-22mm 1:2.8-3.5 Olympus M.Zuiko Digital 45mm 1:1.8 Olympus M.Zuiko Digital 17mm 1:1.8 +9 more
Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 17,343Gear list
Like?
Re: Need 1,000 fps at least.....
In reply to Guy Parsons, 5 months ago

Guy Parsons wrote:

Anders W wrote:

What about shooting a video of the sequence with another camera and play it back frame by frame?

In the past I've done a 1,000 fps video of the E-PL5 shutter in action, but it definitely needs something better than my Casio ZR1000 to do that as things are still blurred frame by frame.

All I see in normal E-PL5 shutter operation is the shutter closing (with a huge amount of bounce) to darken the sensor and clear it, then the shutter curtains run, then the shutter stays closed for about 1/10 second for the unload time, then back to live view.

http://i100.photobucket.com/albums/m36/photoguy340/dprstuff/epl5shutter2_zps60fc6f28.gif

Very low resolution and slowed down of course in this animated gif (which, darn it, DPReview can't display here like it could before).

If only Olympus would lend me cameras to play with and then I could try E-M1 and E-M10 and see how they operate.....

Yeah, I realize we are dealing with some fast action here.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
Jim Salvas
Senior MemberPosts: 2,648Gear list
Like?
Re: Need 1,000 fps at least.....
In reply to Guy Parsons, 5 months ago

Guy Parsons wrote:

If only Olympus would lend me cameras to play with and then I could try E-M1 and E-M10 and see how they operate.....

You could tell them they need you to verify operations in the anti-gravity of Sydney.

-- hide signature --

Jim Salvas

 Jim Salvas's gear list:Jim Salvas's gear list
Olympus PEN E-PM2 Olympus E-M1 Panasonic Lumix DMC-GH4 Olympus M.Zuiko Digital 14-42mm 1:3.5-5.6 II R Olympus M.Zuiko Digital ED 40-150mm 1:4-5.6 R +8 more
Reply   Reply with quote   Complain
danstroud
Forum MemberPosts: 66Gear list
Like?
Re: Shutter video
In reply to simpy, 5 months ago

Interesting idea… maybe that could be tested by making a recording of the shutter sounds to see if if takes a bit longer for the second shutter to close when in the EFC mode?

 danstroud's gear list:danstroud's gear list
Panasonic Lumix DMC-GH2 Panasonic Lumix DMC-GF2 Panasonic Lumix DMC-GX7 Olympus E-M1 Panasonic Lumix G 20mm F1.7 ASPH +5 more
Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 17,343Gear list
Like?
Re: Shutter video
In reply to simpy, 5 months ago

simpy wrote:

Jim Salvas wrote:

I just took that clip into iMovie, where I can slow it down to frame by frame. It definitely seems as if the first curtain is closing and then opening again, but it sure is fast. When you listen to it frame by frame, there are quite a few shutter sounds going on.

Could it be that the physical shutter sequence is not altered, but the electronic shutter makes it possible to adjust the timing of the actions?

For example, the initial curtain could close and reopen as quickly as possible, before the camera/sensor is ready to shoot. That might give a few milliseconds for things to settle down before the electronic shutter starts exposure.

Yes, it could be like that. And I think it's the best guess I can make after seeing Jim's video. There is no way to download it from youtube or viewing it frame by frame on youtube, is there?

It could be that the mechanical shutter is so constructed that there is simply no way to use the second curtain only so that they have to go through the entire sequence.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
lattesweden
Regular MemberPosts: 287
Like?
Re: Shutter video
In reply to Anders W, 5 months ago

Does anyone here know the difference between electronic shutter and electronic first curtain?

And I mean that from a timing perspective. Electronoic shutters scan row by row as we know. How does the electronic first curtain operate from that perspective? Wouldn't it have to use the same row by row mechanism as a fully electronic shutter to open the "feed" to the memory but instead of switching the feed off electronically it uses the real shutter curtain that just shuts the light out and then the electronic feed is also cut and the file saved. And the camera can after that again open the real first curtain and go back to live view?

Or does it work differently?

-- hide signature --

Best regards
/Anders
----------------------------------------------------
I'm from Sweden, but my pictures are in all languages: http://500px.com/anderslattermann

Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 17,343Gear list
Like?
Re: Shutter video
In reply to lattesweden, 5 months ago

lattesweden wrote:

Does anyone here know the difference between electronic shutter and electronic first curtain?

And I mean that from a timing perspective. Electronoic shutters scan row by row as we know. How does the electronic first curtain operate from that perspective? Wouldn't it have to use the same row by row mechanism as a fully electronic shutter to open the "feed" to the memory but instead of switching the feed off electronically it uses the real shutter curtain that just shuts the light out and then the electronic feed is also cut and the file saved. And the camera can after that again open the real first curtain and go back to live view?

Or does it work differently?

No it works pretty much the way you describe. An electronic shutter resets the sensor (empties the capacitors that store the charges) row by row and then reads the sensor row by row. An electronic first curtain resets the sensor row by row and then finishes the exposure row by row by having the second mechanical shutter curtain pass over them. Read-out in this case starts only after exposure is mechanically finished.

The critical difference is the time limits involved. With current sensors, read-out takes time if it is to be done well, without adding too much noise. And since read-out must be slow, the reset with current electronic shutter must be equally slow. Otherwise, the two processes wouldn't synch and exposure would vary across the frame.

Consequently, the electronic shutters we currently have on Pany bodies take between 1/10 and 1/25 s to finish the exposure across the entire frame, which makes them unsuitable in some situations (because of so-called rolling shutter or "jello" effects due to camera or subject movement during the long total exposure time). And cutting the time down to 1/25 s comes at the expense of more noise. At full quality, it's 1/15 s at best.

However, reset can be done more quickly than read-out, apparently as quickly as 1/320 s (the max speed of the EFCS of the E-M1) or faster, which is more than ten times as fast as an electronic shutter. So with an EFCS you can have some of the benefits of an electronic shutter (no blur due to the movements of the first curtain of a mechanical shutter) without the downside of "jello" effects.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
lattesweden
Regular MemberPosts: 287
Like?
Re: Shutter video
In reply to Anders W, 5 months ago

Thanks Anders for that good explanation!

Is there any technical reason why electronic first curtain can't be added to other M43 cameras as a firmware update like what Oly just did?

I know Sony for instance says that A7r can't have it so something must be different in how things can work?

-- hide signature --

Best regards
/Anders
----------------------------------------------------
I'm from Sweden, but my pictures are in all languages: http://500px.com/anderslattermann

Reply   Reply with quote   Complain
Keyboard shortcuts:
FForum MMy threads