Olympus UK E-System User Group
Olympus UK E-System User Group

Join our unique resource for Olympus Four Thirds E-System DSLR and Pen and OM-D Micro Four Thirds photographers. Show your images via our free e-group photo gallery. Please read the e-group.uk.net forum terms and conditions before posting for the first time. Above all, welcome!


Go Back   Olympus UK E-System User Group > Cameras, lenses and system accessories > Camera conference > Micro Four Thirds > Olympus OM-D E-M1

Olympus OM-D E-M1 The first Micro Four Thirds camera that offers phase detect focusing so you can use Four Thirds DSLR lenses normally as well a Micro Four Thirds lenses.

Reply
 
Thread Tools Display Modes
  #1  
Old 14th September 2013
DerekW DerekW is offline
Full member
 
Join Date: Nov 2007
Location: Hampshire
Posts: 3,082
Thanks: 90
Thanked 334 Times in 261 Posts
Likes: 33
Liked 534 Times in 373 Posts
Mechanics of exposure??

I assume that this camera has a focal plane shutter - or does it rely of grabbing the contents of the sensor when the shutter release is pressed.

If a physical shutter is involved then when the shutter release is pressed then I assume the following sequence of events occurs.

Exposure settings stored for use
Shutter is closed
Sensor is cleared of any information left in it from the live view
Shutter is activated exposing the sensor for the required time, as well as stopping down the lens.

After the shutter is closed the data on the sensor is written away to be processed and stored on the memory card.

The shutter is then opened for the sensor to display the scene to the live view viewfinder.

Is this valid description of the process.

What is the lag time from pressing the shutter release to the exposure taking place?

In the past with non DSLR cameras where the above process took place the subject had often moved out of the picture. How does the new camera perform?

Thanks for any info - Just curious!
__________________
This space for rent
Reply With Quote
  #2  
Old 14th September 2013
Ian's Avatar
Ian Ian is offline
Administrator
 
Join Date: Jul 2007
Location: Hemel Hempstead, Hertfordshire, UK
Posts: 11,567
Thanks: 423
Thanked 2,522 Times in 1,269 Posts
Likes: 864
Liked 1,696 Times in 769 Posts
Re: Mechanics of exposure??

I dunno, I go to all that trouble to write articles about the new camera and nobody reads them!

http://fourthirds-user.com/2013/09/o...plained_.php/h

Ian
__________________
Founder and editor of:
Olympus UK E-System User Group (http://e-group.uk.net)
Four Thirds User (http://fourthirds-user.com)
Digital Photography Now (http://dpnow.com)
Olympus camera, lens, and accessory hire (http://e-group.uk.net/hire)

Twitter: www.twitter.com/ian_burley
Flickr: www.flickr.com/photos/dpnow/
Pinterest: www.pinterest.com/ianburley/
NEW: My personal BLOG ianburley.com

Last edited by Ian; 14th September 2013 at 02:19 PM. Reason: Correction! Camera not 'computer'!
Reply With Quote
  #3  
Old 14th September 2013
DerekW DerekW is offline
Full member
 
Join Date: Nov 2007
Location: Hampshire
Posts: 3,082
Thanks: 90
Thanked 334 Times in 261 Posts
Likes: 33
Liked 534 Times in 373 Posts
Re: Mechanics of exposure??

Thanks for the pointer
__________________
This space for rent
Reply With Quote
  #4  
Old 14th September 2013
Ian's Avatar
Ian Ian is offline
Administrator
 
Join Date: Jul 2007
Location: Hemel Hempstead, Hertfordshire, UK
Posts: 11,567
Thanks: 423
Thanked 2,522 Times in 1,269 Posts
Likes: 864
Liked 1,696 Times in 769 Posts
Re: Mechanics of exposure??

I think your description of the exposure/shutter cycle is essentially correct, Derek.

I don't have a figure for the shutter lag, but it is basically not noticeable. Olympus does offer a figure for the latency between subject movement and the same movement in the electronic viewfinder - 29ms.

Which camera model do you currently use? Maybe I can relate the E-M1 responsiveness to that?

Ian
__________________
Founder and editor of:
Olympus UK E-System User Group (http://e-group.uk.net)
Four Thirds User (http://fourthirds-user.com)
Digital Photography Now (http://dpnow.com)
Olympus camera, lens, and accessory hire (http://e-group.uk.net/hire)

Twitter: www.twitter.com/ian_burley
Flickr: www.flickr.com/photos/dpnow/
Pinterest: www.pinterest.com/ianburley/
NEW: My personal BLOG ianburley.com
Reply With Quote
  #5  
Old 14th September 2013
josephlck josephlck is offline
Full member
 
Join Date: Jun 2012
Location: London
Posts: 60
Thanks: 2
Thanked 5 Times in 5 Posts
Likes: 0
Liked 1 Time in 1 Post
Re: Mechanics of exposure??

Just an interesting tit bit of information, it takes 120ms from the time light enters your eyes for it to travel to your visual cortex. And that's just the time for the electrical signal to reach. It still has to be processed!!

I suppose not really relevant except to put Ian's figure of 29ms in context but it blew my mind when I first found out: everything you see as "now" happened at least 120ms ago.

P.S. if anyone is wondering where the figure comes from, it's a medical test called visual evoked potential and is a test of the conduction along your optic nerve.
Reply With Quote
The Following User Says Thank You to josephlck For This Useful Post:
Xenon (14th September 2013)
  #6  
Old 14th September 2013
Ian's Avatar
Ian Ian is offline
Administrator
 
Join Date: Jul 2007
Location: Hemel Hempstead, Hertfordshire, UK
Posts: 11,567
Thanks: 423
Thanked 2,522 Times in 1,269 Posts
Likes: 864
Liked 1,696 Times in 769 Posts
Re: Mechanics of exposure??

Quote:
Originally Posted by josephlck View Post
Just an interesting tit bit of information, it takes 120ms from the time light enters your eyes for it to travel to your visual cortex. And that's just the time for the electrical signal to reach. It still has to be processed!!

I suppose not really relevant except to put Ian's figure of 29ms in context but it blew my mind when I first found out: everything you see as "now" happened at least 120ms ago.

P.S. if anyone is wondering where the figure comes from, it's a medical test called visual evoked potential and is a test of the conduction along your optic nerve.
Interesting

Obviously we all experience what seems to be a lag-free world so it would seem that the natural lag is compensated for by our brains.

The viewfinder lag of 29ms will be added on top of the human lag...

Ian
__________________
Founder and editor of:
Olympus UK E-System User Group (http://e-group.uk.net)
Four Thirds User (http://fourthirds-user.com)
Digital Photography Now (http://dpnow.com)
Olympus camera, lens, and accessory hire (http://e-group.uk.net/hire)

Twitter: www.twitter.com/ian_burley
Flickr: www.flickr.com/photos/dpnow/
Pinterest: www.pinterest.com/ianburley/
NEW: My personal BLOG ianburley.com
Reply With Quote
  #7  
Old 14th September 2013
OM USer's Avatar
OM USer OM USer is offline
Full member
 
Join Date: Jun 2012
Location: London
Posts: 12,022
Thanks: 2,371
Thanked 1,493 Times in 1,421 Posts
Likes: 6,169
Liked 1,405 Times in 896 Posts
Re: Mechanics of exposure??

Quote:
Originally Posted by Ian View Post
Obviously we all experience what seems to be a lag-free world ...
I did read somewhere that when playing tennis you start to hit the ball before it has even come your side of the net. Clearly we all have a predictive capacity that can adjust for "lag".

The main reason why I invested in an E-M5 was that my elderly P&S suffered not only from a slowish focus but also shutter lag - the time taken once focus had been established to actually exposing for the picture. Although this is now very quick on modern mirrorless cameras (Olympus and Panasonic being especially good across the entire range) I'm sure that it would put the 29ms EVF lag into perspective.
Reply With Quote
  #8  
Old 14th September 2013
DerekW DerekW is offline
Full member
 
Join Date: Nov 2007
Location: Hampshire
Posts: 3,082
Thanks: 90
Thanked 334 Times in 261 Posts
Likes: 33
Liked 534 Times in 373 Posts
Re: Mechanics of exposure??

I use an E5, my comments/concerns are based on my pre DSLR days when the cameras were very slow - to see if a camera was suitable I would press the shutter when a walking person passed a marker on the pavement and then see what was on the picture - on many times the person was out of the frame. When I was taking lots of dog pictures I managed to get lots of pictures of dog's tails. Hence a move to the E20 and then to the E1 and managed to get the head and tail of the dog in the same picture.
__________________
This space for rent
Reply With Quote
  #9  
Old 14th September 2013
Ian's Avatar
Ian Ian is offline
Administrator
 
Join Date: Jul 2007
Location: Hemel Hempstead, Hertfordshire, UK
Posts: 11,567
Thanks: 423
Thanked 2,522 Times in 1,269 Posts
Likes: 864
Liked 1,696 Times in 769 Posts
Re: Mechanics of exposure??

Quote:
Originally Posted by DerekW View Post
I use an E5, my comments/concerns are based on my pre DSLR days when the cameras were very slow - to see if a camera was suitable I would press the shutter when a walking person passed a marker on the pavement and then see what was on the picture - on many times the person was out of the frame. When I was taking lots of dog pictures I managed to get lots of pictures of dog's tails. Hence a move to the E20 and then to the E1 and managed to get the head and tail of the dog in the same picture.
OK, well the E-M1 will be just as responsive, maybe more so, than an E-1 or your E-5.

Ian
__________________
Founder and editor of:
Olympus UK E-System User Group (http://e-group.uk.net)
Four Thirds User (http://fourthirds-user.com)
Digital Photography Now (http://dpnow.com)
Olympus camera, lens, and accessory hire (http://e-group.uk.net/hire)

Twitter: www.twitter.com/ian_burley
Flickr: www.flickr.com/photos/dpnow/
Pinterest: www.pinterest.com/ianburley/
NEW: My personal BLOG ianburley.com
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Exposure Graham_of_Rainham The lounge 0 3rd July 2013 02:23 PM
Mechanics post2cd Looking for improvement 8 20th November 2012 05:37 PM
exposure Homer Simpson Olympus E-1 4 30th October 2011 04:48 PM
Exposure 3 Usy Foto Fair 1 20th September 2011 12:55 PM
Double exposure Ijay37 Olympus E-3 5 13th January 2008 12:58 PM


All times are GMT. The time now is 11:45 AM.


The Write Technology Ltd, 2007-2019, All rights reservedAd Management plugin by RedTyger