Jump to content

Slowest shutter speed in video mode


shooter
 Share

Recommended Posts

EOSHD Pro Color 5 for Sony cameras EOSHD Z LOG for Nikon CamerasEOSHD C-LOG and Film Profiles for All Canon DSLRs
Guest Ebrahim Saadawi

rich is right

No he's not. 

To this point I still didn't explain my words as I thought it's too easy and there's no need for it, but apparently not, even for super intelligent guys like rich (who built a 70mm camera with his bare hands!)

Here it go: Your camera takes a number of photographs consecutively when shooting video, the term ''frame rate'' means how many photographs are taken each one second.

Each one of these photographs has a duration of exposure to light, so the term ''shutter speed'' means how long each one of these photographs is being taken/exposed.

Now that we've layin down the basics,

lets take 25 frames per second. Meaning, during each one second, 25 photographs are taken. So what is the maximum exposure duration for each of the 25 photos in each second? We take the second, slice it into 25 pieces, and each piece is the maximum shutter speed. 1/25s.

You can't go longer, you cant get bigger slices. For example 1/5s exposure at 25p, as, this means each one photograph is being taken in fifth of a second, so in one second you can only fit five of them, thus, you're shooting 5 frames per second where each frame is being captured for 1/5s.

So, the absolute minimum shutter speed you can physically go = 1/frame-rate

Now onto the Sony cameras and Canon SLRs: these cameras allow you to shoot at a lower frame rate than standard, and thus lower shutter speed. For example lets you shoot with a 1/5s shutter (therefore 5fps), and then conforms the file to 25p by showing 25 frames of them each second instead of just 5, speeding the playback by 5 times from 5fps to 25fps, thus giving you timelapse/fast-motion effect. This is the same concept as shooting at a higher frame rate, for example 120p, then the camera conforms it down to 25p by showing only 25 frames of the 120 each second, thus creating the slowmotion effect. Some cameras let you do the conversion to 25p in post production and some cameras do it in-camera thus giving Richard a 25p read by his NLE.

I hope this was clear and not confusing.

Link to comment
Share on other sites

Might be so with a mechanical shutter, but we don't know what exactly is going on with an electronic shutter, do we? There's software involved and it's hard to know what's being done in camera, there might be some magical readout mojo going on which you might not be able to emulate in post.

exactly.  It's obvious that a mechanical shutter can't have a longer exposure than 360degrees or the full length of the frame.  It may be a wrapper, I couldnt give two hoots really, I see on my camera 1/5th of a second.  the electronic shutter is open for 1/5th of a second, then closes, exposing 5 frames at a time.  it could be that its 5fps/360degree but for the purposes of this topic, for the final time, as far as I am aware the Sony cameras allow the slowest 'shutter speed' to be selected during video mode.  the effect cannot be achieved without this setting. 

Link to comment
Share on other sites

Funny discussion...:) 
What Sekhar said is absolutely correct:
"It's shooting at 5 fps and interpreting as 25 fps to deliver at 25 fps as a convenience. If it delivered at 5 fps you'd have had to interpret it as 25 ftps manually in the editor, but the result would be the same. The point is that it's capturing at 5 fps, not 25 fps: it's impossible to capture any faster than 5 fps because by the time it's time to capture the next frame it'd still be capturing the first one."

All what Ebrahim Saadawi said is absolute correct!

And it´s also correct, what richg101 said: The Sony A7r2 allows you to shoot 5fps with 1/5th of a second shutter speed.

But again: "It's shooting at 5 fps and interpreting as 25 fps to deliver at 25 fps as a convenience. If it delivered at 5 fps you'd have had to interpret it as 25 ftps manually in the editor, but the result would be the same!"

Interpreting 5fps as 25fps simply means:
Frame 1 - five times same frame,
Frame 2 - five times same frame
and so on... 5x5 = 25

Link to comment
Share on other sites

Back to the topic: 
what's the slowest shutter setting in video on these cameras:
GH4?


I don´t have a Panasonic camera, but I´ve read that on the GH3 there is an option of a percentage increase/decrease (instead of frame rates).
For example 500% (means 5fps - 5x faster when played in a 25fps timeline).
Slow it down to 20% (5x slower) in the editor should be the same effect - but I don´t know if there´s the same option on the GH4...
...and don´t know, how slow the shutter speed works in this percentage mode, but I expect a 360 degrees equivalent (1/5th for 5fps, for example).

Link to comment
Share on other sites

Guest Ebrahim Saadawi

Might be so with a mechanical shutter, but we don't know what exactly is going on with an electronic shutter, do we? 

It's obvious that a mechanical shutter can't have a longer exposure than 360degrees or the full length of the frame.  

Or using the mechanical shutter instead?

Both electronic and mechanical shutters are the same in this, for both minimum shutter speed = 1 / frame-rate. It has nothing to do with it.

Link to comment
Share on other sites

I am not. The point is you come with 1fps, 2 fps... Didn't you understand the original topic?
 24/25fps, 24/25fps, 24/25fps... And if people here prefer to believe always in the some fancy boring theory that's not possible because of this or that, it can work it out to your books, but Sony proves 24/25fps is possible with 1/4th shutter. Period. I am only trying to know what cameras of different brands do the same.

Link to comment
Share on other sites

Guest Ebrahim Saadawi

Sony proves 24/25fps is possible with 1/4th shutter. Period. 

No it doesn't. It can't. Explanation above. 

 I am only trying to know what cameras of different brands do the same.

The ones I remember are all Canon DSLRs (ML).

Edit: also remembered gh4, fs100, c100, in fast-motion mode)

(**and if you want really low shutter, like 1/2s-1/3s (not 1/15s or so) you can do it with all stills cameras (both the ones with mechanical shutters but better in cameras with electronic shutters)

 

Link to comment
Share on other sites

You're only disrupting the original topic of the idea.

1) https://vimeo.com/135120108

2) In your Canons the MECHANICAL shutter will end in a 150,000 cycle...

What part didn't you understand?

 

Edit: also remembered gh4, fs100, c100, in fast-motion mode)
 

Are you sure? Funny, my GH1 doesn't allow me to go lower than 1/30th. Making videos at normal speed, not odd frame rates.

Link to comment
Share on other sites

Guest Ebrahim Saadawi

I give up.

The Sony cameras shoot 1/5s shutter at 25p, they just do it. 

And they're the only cameras that can do this unparalleled trick. 

Get one, shoot in that mode, make great footage and enjoy. Really. 

Link to comment
Share on other sites

There has been some devellopment since then without telling you, apparently.

ftp://ftp.panasonic.com/camera/dmcgh4/dmc-gh4_en_advanced_om.pdf#page215

But, it isn't the same... https://vimeo.com/135120108

It is?

Seems you guys think there's some contest here to show off Sony. It is not.

There's a feature. Topic of this thread. What are the cameras to do it (4k without the abuse of mechanical shutter)?

Some Sony. What else?

Signs a brand agnostic.

Link to comment
Share on other sites

Guest Ebrahim Saadawi

But, it isn't the same... https://vimeo.com/135120108

It is?

It is. 

 What are the cameras to do it?

-Sony's A7 series, rx10, rx100 series 

-All Canon (DSLRs starting from 1100D to 5Diii, eos m1/2/3, C100/300 mark I and mark II, XC10 (at 4k), camcorders like the xf105/205/305 xa10,)

-Panasonic GH4 and FZ1000 and G7 and others

-All Blackmagic cameras (at 4K except pocket, HD)

-All Pentax DSLRs (at 4K)

-All camcorders (af100, fs100, fs700, fs7, xf, x300k, x70, ex1/3, hpx series, canon entire beginner vixia line and pro xf line, jvcs handycams up to ls300,)

-Film cameras

-My Samsung wb305 point and shoot, Galaxy cameras, Samsung S6 and note4 smartphones,

there's more if you check.

 

I am merely trying to help you OP (and readers) understand a feature and its availability therefore make an informed buying choice from the cameras you asked about in the OP.

 

Link to comment
Share on other sites

I don't doubt. But you are inaccurate here.

It is.

To begin with, you say it is the same. It isn't: GH4 does variable frame rate BUT 1080p, so?

Then it is easier to understand me the OP I am not intending to use a mechanical shutter (with limited cycles of use) but looking after 24 or 25fps video look you repeatedly say it is not possible to go slower than 1/24th of shutter, so?

 

-Sony's A7 series, rx10, rx100 series 

-All Canon (DSLRs starting from 1100D to 5Diii, eos m1/2/3, C100/300 mark I and mark II, XC10 (at 4k), camcorders like the xf105/205/305 xa10,)

-Panasonic GH4 and FZ1000 and G7 and others

-All Blackmagic cameras (at 4K except pocket, HD)

-All Pentax DSLRs (at 4K)

-All camcorders (af100, fs100, fs700, fs7, xf, x300k, x70, ex1/3, hpx series, canon entire beginner vixia line and pro xf line, jvcs handycams up to ls300,)

-Film cameras

-My Samsung wb305 point and shoot, Galaxy cameras, Samsung S6 and note4 smartphones,

there's more if you check.

Where those cameras are doing 1/4th at normal speed of 24 or 25fps look? (slowest shutter in video mode with my GH1 for example is 1/30)

Didn't you say it is impossible? You're entering in contradiction lol

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • EOSHD Pro Color 5 for All Sony cameras
    EOSHD C-LOG and Film Profiles for All Canon DSLRs
    EOSHD Dynamic Range Enhancer for H.264/H.265
×
×
  • Create New...