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 > Site news and information > Tutorials, Informative & Classic threads

Tutorials, Informative & Classic threads A new e-Group area for all the wonderful tutorials and helpful threads put on here by our members. Tutorials on using software, camera hardware - and feel free to request a tutorial if you need assistance!

Reply
 
Thread Tools Display Modes
  #1  
Old 4th June 2014
Ricoh Ricoh is offline
Full member
 
Join Date: Apr 2014
Location: Lancashire
Posts: 5,792
Thanks: 592
Thanked 421 Times in 373 Posts
Likes: 787
Liked 1,919 Times in 1,143 Posts
Expose to the right

I'm not sure if I'm posting in the correct section?

Given the dynamic range of digital sensors (5 or 6 stops) and the distribution such that each stop records half the light of the previous one, I'm considering the technique 'expose to the right', and correcting in RAW.
Can't see a tutorial here, but any tips / advice would be welcome
__________________
Steve

on flickr
Reply With Quote
  #2  
Old 4th June 2014
Pjphoto59's Avatar
Pjphoto59 Pjphoto59 is offline
Stock Shooter
 
Join Date: Nov 2007
Location: Marske-by-the-Sea, Cleveland
Posts: 699
Thanks: 23
Thanked 64 Times in 48 Posts
Likes: 3
Liked 59 Times in 35 Posts
Re: Expose to the right

It is certainly a good technique for maximising DR. It is OK to clip highlights if they are small parts of the image area.

Always shoooting RAW, I only find it to be necessary to consciously "shoot to the right" in very challenging (dark) situations, in easier circumstances I just use evaluative metering and +0.3 exposure and PP the RAW file in LR5.

When there is no sky in the frame, I up the exposure correction to +0.7.
__________________
Peter J

OM-D E-M1 OMD-E-M5ii Various Olympus lenses
Reply With Quote
  #3  
Old 5th June 2014
byegad byegad is offline
Full member
 
Join Date: Oct 2013
Location: NE England
Posts: 771
Thanks: 20
Thanked 99 Times in 93 Posts
Likes: 106
Liked 151 Times in 105 Posts
Re: Expose to the right

It seems to be accepted wisdom that blown highlights cannot be brought back, but underexposed areas can be brought up to reveal details. By exposing to the right isn't that the same as over exposing? As a relative newbie I ask for clarification.
__________________
Too many cameras!
E-500, E-510, EPM1, EPL5, EP3, EP5, OM-D E M10, OM-D E M5, Trip 35mm, Samsung WP10 and Panasonic G6 plus lots of lenses many manual focus.

Photos at http://www.flickr.com/photos/42941818@N07/
Reply With Quote
  #4  
Old 5th June 2014
Zuiko's Avatar
Zuiko Zuiko is offline
Administrator
 
Join Date: Nov 2007
Location: Dunmow, Essex
Posts: 22,133
Thanks: 1,987
Thanked 3,164 Times in 2,472 Posts
Likes: 3,423
Liked 4,474 Times in 2,125 Posts
Re: Expose to the right

Quote:
Originally Posted by byegad View Post
It seems to be accepted wisdom that blown highlights cannot be brought back, but underexposed areas can be brought up to reveal details. By exposing to the right isn't that the same as over exposing? As a relative newbie I ask for clarification.
No, because even though you are shifting the histogram to the right you still don't want to clip it. This technique works best for preserving shadow detail in poor light with limited dynamic range. It is still useful, however, for scenes with a wide dynamic range where you would adjust the exposure until the histogram just meets the right-hand edge but is not clipped by it. Of course, by doing this you are still sacrificing some of the shadows, but at least it is kept to a minimum. In practice, when shooting raw you can still recover some of the clipped detail in pp providing it is not too extreme.

Best practice:

Shoot raw in challenging light.

Use base ISO (200) if you are able.

Keep histogram as far to the right as possible without clipping.

Bracket exposures in 0.3 stops if situation allows, you can choose the best later.

Consider using graduated ND filters to control dynamic range when shooting landscapes, or HDR or exposure blending from two or more bracketed frames.
__________________
John

"A hundredth of a second here, a hundredth of a second there even if you put them end to end, they still only add up to one, two, perhaps three seconds, snatched from eternity." ~ Robert Doisneau
Reply With Quote
The Following User Liked This Post:
Floribunda (5th June 2014)
  #5  
Old 5th June 2014
byegad byegad is offline
Full member
 
Join Date: Oct 2013
Location: NE England
Posts: 771
Thanks: 20
Thanked 99 Times in 93 Posts
Likes: 106
Liked 151 Times in 105 Posts
Smile Re: Expose to the right

Thanks for that John, very clear and logical once you understand what the term means.
__________________
Too many cameras!
E-500, E-510, EPM1, EPL5, EP3, EP5, OM-D E M10, OM-D E M5, Trip 35mm, Samsung WP10 and Panasonic G6 plus lots of lenses many manual focus.

Photos at http://www.flickr.com/photos/42941818@N07/
Reply With Quote
  #6  
Old 5th June 2014
Invicta's Avatar
Invicta Invicta is offline
Full member
 
Join Date: Nov 2007
Location: Third rock from the sun
Posts: 1,022
Thanks: 66
Thanked 243 Times in 125 Posts
Likes: 19
Liked 82 Times in 47 Posts
Re: Expose to the right

There is an alternative view of ETTR discussed here:

http://chromasoft.blogspot.co.uk/200...ain-wrong.html

Worth a read and the follow-up links at the end of the first article.
Reply With Quote
The Following User Says Thank You to Invicta For This Useful Post:
Zuiko (5th June 2014)
  #7  
Old 5th June 2014
Ricoh Ricoh is offline
Full member
 
Join Date: Apr 2014
Location: Lancashire
Posts: 5,792
Thanks: 592
Thanked 421 Times in 373 Posts
Likes: 787
Liked 1,919 Times in 1,143 Posts
Re: Expose to the right

That 'chromasoft' article is an interesting read, one I'll have to read again together with the referenced hyperlinks to get a better impression, but for now, the analysis and argument sounds quite logical. ETTR has benefit only when extending the lower ISO limit of the camera, so it says, and there's a colour shift issue when the end-to-end process of capture-to-print, including post processing, is taken into account. Certainly food for thought!
__________________
Steve

on flickr
Reply With Quote
  #8  
Old 5th June 2014
brianvickers's Avatar
brianvickers brianvickers is offline
Full member
 
Join Date: Mar 2012
Location: UK
Posts: 1,762
Thanks: 21
Thanked 230 Times in 221 Posts
Likes: 2
Liked 87 Times in 54 Posts
Re: Expose to the right

The other reason for exposing to the right is that the range of tones is not evenly distributed throughout the exposure range i.e. in the lowest range (EV0-EV1) there are only 8 tonal steps, but 16 in EV1-EV2 and 32 in the next and doubles up until you end up with 256 tones between EV5 and EV6 - those tones closest to the right therefore have more tonal graduation than those at the other end.
Thus mid tones being registered further towards the right will also benefit from better tonal graduation. This might not be absolutely correct regarding my EV numbers but the principle is correct.......please feel free to correct/elaborate anyone...
__________________
see my blog... http://www.rps.org/my-rps/portfolio
and flickr page...http://www.flickr.com/photos/brianvickers/
Reply With Quote
  #9  
Old 5th June 2014
Ricoh Ricoh is offline
Full member
 
Join Date: Apr 2014
Location: Lancashire
Posts: 5,792
Thanks: 592
Thanked 421 Times in 373 Posts
Likes: 787
Liked 1,919 Times in 1,143 Posts
Re: Expose to the right

That's my understanding as well, and from an arithmetic point of view it would encourage the use of the light sensors accordingly, but the counter argument from cromasoft, which to be fair is basically empirical, would make you stop and think.
__________________
Steve

on flickr
Reply With Quote
  #10  
Old 6th June 2014
David Morison's Avatar
David Morison David Morison is offline
Full member
 
Join Date: Dec 2010
Location: Fulbeck, Lincolnshire
Posts: 3,507
Thanks: 71
Thanked 588 Times in 472 Posts
Likes: 48
Liked 298 Times in 175 Posts
Re: Expose to the right

I don't have a systematic way of dealing with difficult lighting I just have the front dial on the E-M1 assigned to exposure compensation and use that constantly according to the subject, mainly just relying on experience sometimes coupled with the histogram but often exposing to the left.

David
__________________
PBase Galleries:-http://www.pbase.com/davidmorisonimages
Reply With Quote
  #11  
Old 6th June 2014
StephenL's Avatar
StephenL StephenL is offline
Senior Pixelmonger
 
Join Date: May 2008
Location: Yorkshire Dales
Posts: 9,863
Thanks: 984
Thanked 1,126 Times in 921 Posts
Likes: 658
Liked 755 Times in 499 Posts
Re: Expose to the right

With raw, as long as you can see both sides of the live histogram you'll be fine. You can correct in PP without losing detail.

I tend to shift the histogram towards the right if there's room, and I also have a safety margin set to the histogram warnings, so they show clipping at about 2 and 253, thus giving a small amount of user latitude.
__________________
Stephen

A camera takes a picture. A photographer makes a picture

Fuji X system, + Leica and Bronica film

My Flickr site
Reply With Quote
  #12  
Old 6th June 2014
Zuiko's Avatar
Zuiko Zuiko is offline
Administrator
 
Join Date: Nov 2007
Location: Dunmow, Essex
Posts: 22,133
Thanks: 1,987
Thanked 3,164 Times in 2,472 Posts
Likes: 3,423
Liked 4,474 Times in 2,125 Posts
Re: Expose to the right

Quote:
Originally Posted by David Morison View Post
I don't have a systematic way of dealing with difficult lighting I just have the front dial on the E-M1 assigned to exposure compensation and use that constantly according to the subject, mainly just relying on experience sometimes coupled with the histogram but often exposing to the left.

David
In the end, this is the best approach. ETTR is just one technique which often works for a particular type of situation, it's not a panacea for every occasion and there are alternative methods for arriving at the same result.

I'm most likely to use ETTR when shooting landscapes, particularly when the camera is on a tripod. I'll make an exposure with no compensation then assess the histogram (yes, I chimp and I'm proud of it - it's another tool, like having an instant polaroid). Quite often it will be a satisfactory graph, with no clipping on either side but perhaps some bunching towards the left, tapering off to the right. This indicates that the majority of the pixels, including those that have captured the mid-range tones, are less than ideally exposed. In a way, the histogram is a bit like Depth of Field charts; there isn't an abrupt definition between perfect exposure and clipping at each extremity, more like a gradual fall-off of what is acceptable rather than ideal.

In this situation dialing +0.3 compensation may move the histogram a notch to the right, but still without clipping. Try it again and I might get away with +0.7, sometimes even +1. Meanwhile, the greatest mass of pixels, rising to the highest part of the histogram, have shifted more towards the centre, which is where I want the mid-tones to be.

However, be careful. In some situations, such as sunlit flowers against a dark background deep in shadow or an illuminated landscape beneath a stormy sky, you may want an exposure represented by bunching, even clipping, on the left. It's important to match the exposure technique to the subject.
__________________
John

"A hundredth of a second here, a hundredth of a second there even if you put them end to end, they still only add up to one, two, perhaps three seconds, snatched from eternity." ~ Robert Doisneau
Reply With Quote
  #13  
Old 6th June 2014
Jim Ford Jim Ford is online now
Full member
 
Join Date: Dec 2007
Location: Watford, Herts..
Posts: 8,344
Thanks: 457
Thanked 592 Times in 514 Posts
Likes: 2,655
Liked 1,633 Times in 1,045 Posts
Re: Expose to the right

Quote:
Originally Posted by brianvickers View Post
The other reason for exposing to the right is that the range of tones is not evenly distributed throughout the exposure range i.e. in the lowest range (EV0-EV1) there are only 8 tonal steps, but 16 in EV1-EV2 and 32 in the next and doubles up until you end up with 256 tones between EV5 and EV6 - those tones closest to the right therefore have more tonal graduation than those at the other end.
Thus mid tones being registered further towards the right will also benefit from better tonal graduation. This might not be absolutely correct regarding my EV numbers but the principle is correct.......please feel free to correct/elaborate anyone...
That's also my understanding. To not expose to the right reduces the tonal range of the image, risking posterisation in subsequent PPing.

Jim
Reply With Quote
  #14  
Old 6th June 2014
pdk42's Avatar
pdk42 pdk42 is offline
Full member
 
Join Date: Apr 2013
Location: Leamington Spa
Posts: 5,710
Thanks: 370
Thanked 1,257 Times in 942 Posts
Likes: 150
Liked 6,006 Times in 1,955 Posts
Re: Expose to the right

I personally find the blue/orange under/over exposure colouring much easier to use than the live histogram. It's easy to see which parts of the image are blown out and you can then vary the exposure compensation to suit.
__________________
Paul
E-M1ii, Pen-F and too many lenses
flickr
Portfolio Site
Instagram
Reply With Quote
  #15  
Old 7th June 2014
pdk42's Avatar
pdk42 pdk42 is offline
Full member
 
Join Date: Apr 2013
Location: Leamington Spa
Posts: 5,710
Thanks: 370
Thanked 1,257 Times in 942 Posts
Likes: 150
Liked 6,006 Times in 1,955 Posts
Re: Expose to the right

The article that Invicta linked to is interesting. I remember reading it some time ago and was persuaded of his logic. However, it's worth pointing out that his tests are using some pretty old versions of the raw processors and things may not be the same today. That doesn't necessarily invalidate the conclusion of course.

Another problem with ETTR is knowing when you've gone too far right. I find that the Oly cameras will show things as being blown when in fact none of the 3 channels has reached that point. That leads me to allow some overexposure indication (orange blinkies) but not too much. Of course, the blinkies and live histogram are only showing a composite view over all channels so it's possible for one channel to saturate without it being too obvious. This is often a problem with the red channel and it leads to colour shifts (e.g. on flowers).

Finally, the Oly sensors are actually pretty good at keeping the noise under control when you push shadows. I remember doing some comparison shots between a 5dii and an E-PL5 when I first got into u43. Pushing one shot with lots of deep shadow, the Oly did significantly better than the Canon which showed lots of noise and banding well before the Oly struggled.

For all these reasons, I no longer fret about ETTR and just take as-well-exposed shots as I can.
__________________
Paul
E-M1ii, Pen-F and too many lenses
flickr
Portfolio Site
Instagram
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
How do I over or under expose with Auto ISO DerekW Olympus OM-D E-M1 27 20th May 2014 01:09 AM
How do I prepare and expose correctly for externally mounted flash? theMusicMan Camera conference 8 9th April 2008 06:31 AM


All times are GMT. The time now is 05:08 PM.


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