1. Reminder: Please use our affiliate links for holiday shopping!

Pushing ISO on OM-D

Discussion in 'Olympus Cameras' started by pdk42, Jul 25, 2013.

  1. pdk42

    pdk42 One of the "Eh?" team

    Jan 11, 2013
    Leamington Spa, UK
    My interest was piqued by this post on Luminous Landscape:

    Michael Reichmann, ETTR and Oly OMD EM5

    This excellent chart by Bill Claff suggests that after ISO 400 you get very little IQ improvement raising the ISO on an EM5 - I would stop thereabouts because every time you raise the ISO by one stop you reduce highlight headroom by the same amount. For instance if you are 'properly' ETTR'd at ISO1600, you only gain about 0.1 of a stop in noise performance compared to ISO 400 (I challenge you to see the difference :), but you give up two stops of highlight headroom. Of course in such a situation ISO 400 most likely entails correcting brightness in post.

    So, I decided to do a little experiment. The following image shows two shots of the same scene viewed at 100% and with no NR applied. The one on the left is normally exposed at ISO 3200; the one on the right is underexposed by 3 stops at ISO 400 (so has the same shutter speed/aperture as the ISO 3200 shot). I've then pushed the ISO 400 image 3 stops in Lightroom.

    [​IMG]

    Click here for full-size image

    As you can see, there is virtually no difference to the noise. I'm undecided whether the ISO 400 shot shows more DR - guess it's hard to see in this shot, but if you go to the thread I referenced above and consult the chart, you'll see that is apparently the case.

    Interesting...
     
  2. GaryAyala

    GaryAyala Mu-43 Legend

    Jan 2, 2011
    SoCal
    I've always wondered if raising the ISO in-camera would have the same/equal negative effects as moving the sliders in post on an under-exposed image.

    Gary
     
  3. pdk42

    pdk42 One of the "Eh?" team

    Jan 11, 2013
    Leamington Spa, UK
    It seems to depend on the sensor. The Sony Exmoor sensors (Nikon D7000, Oly E-M5 etc) are nicknamed 'ISOless' by some since you can heavily underexpose and fix later without too much impact on the final image. I've seen D7000 images pushed 7 stops and still look acceptable.

    It's a completely different story on Canon sensors. Pushing in post will wreck the IQ.
     
  4. GaryAyala

    GaryAyala Mu-43 Legend

    Jan 2, 2011
    SoCal
    Ahhh ... now it makes more sense. Having Canons, everything sorta goes to hell real quick when under-exposing.

    Gary
     
  5. With_Eyes_Unclouded

    With_Eyes_Unclouded Mu-43 All-Pro

    Apr 17, 2012
    Vassilios
    When I still had Canons, the main issue (esp. with APS-C sensors, but, up to a point, with the 5D as well) was the dreaded banding noise patterns that could develop after pushing in post.

    Pekka Potka wrote at some point that it's possible Olympus has the industry's best mettering/ETTR algorithms available. I don't know how true this is, any exposure problems I have are mainly due to my inabillity I guess, given automatic modes work almost flawlesly.

    That said, the term "ISOless" suits those sensors; I'm usually able to pull/push detail out of highlights/shadows with ease. A friend of mine working with the D800 swears you can shoot paying almost no attention to exposure, since the sensor can reveal an astonishing amount of detail in post.
     
  6. uci2ci

    uci2ci Mu-43 All-Pro

    Jun 22, 2012
    Los Angeles, CA
    Sam
    Very useful comparison. I have the habit of underexposing when I need more shutter speed. Quicker than raising ISO. I guess its not that bad of a habit afterall. But i wonder what the results would be if you had deeper shadows . Underexposing a shot like that might clip the shadows making it harder to recover as oppose to a high ISO shot.
     
  7. brettmaxwell

    brettmaxwell Mu-43 Veteran

    350
    Dec 8, 2012
    I haven't pushed my OMD as hard as D800 and D600 files, but it's true these Sony sensors are really, really incredible with shadow detail. It really is a game-changer if you're shooting raw and post processing all your photos.
     
  8. robbie36

    robbie36 Mu-43 All-Pro

    Sep 25, 2010
    Bangkok
    rob collins
    Interesting discussion and it is something I have wondered about - it does start to make my head spin after a while.

    Incidentally if this is inherently true, it rather implies that the positive benefits of ETTR are grossly overstated.
     
  9. GaryAyala

    GaryAyala Mu-43 Legend

    Jan 2, 2011
    SoCal
    Oddly true.
     
  10. htc

    htc Mu-43 Top Veteran

    579
    Jan 11, 2011
    Finland
    Harry
    Pekka Potka had some examples in favor of ETTR...
     
  11. stripedrex

    stripedrex Do or do not. There is no try.

    374
    Jun 8, 2012
    Long Island, NY
    Alex
    Hmm, does this mean we should all lock our max ISO to 400? =p And did I read this correct upping exposure in post retains more dynamic range than properly exposing to higher iso on OMD?
     
  12. robbie36

    robbie36 Mu-43 All-Pro

    Sep 25, 2010
    Bangkok
    rob collins
    Actually I was guilty of not looking close enough at the original link. Anyway I have taken the original chart and added the Nikon 800.

    iso.JPG

    This really confirms what other people have mentioned in the thread. The Canon 5D chart looks very different from the flat Sony sensor OMD and Nikon D800 charts. Theoretically you could expose properly at iso 6400 and underexpose 5 stops at iso 200 with Nikon D800 and the results would be near identical.
     
  13. robbie36

    robbie36 Mu-43 All-Pro

    Sep 25, 2010
    Bangkok
    rob collins
    Yes I found that thanks. The article is here....

    pekkapotka - Journal - Olympus E-M5: Exposing (to the right) and Lightroom 4.1

    It seems petty convincing.

    I think that the 2 arguments can be broadly reconciled. The OMD curve is quite steep in the initial phases - a properly exposed iso 400 shot will be 0.5 stops cleaner than a 1stop underexposed iso 200 shot pushed. So that ETTR has benefits when used at base iso but not much beyond.
     
  14. LowriderS10

    LowriderS10 Monkey with a camera.

    May 19, 2013
    Canada
    Hmm...I haven't been very happy with pushing the OM-D (but have been satisfied when exposed properly), especially at lower ISOs...and, yeah, the "lesser" Canons don't like to be pushed, but especially the 5D and the 5D2 take reaaaaaaaally well to pushing...I remember being blown away the first few times I pushed hard on my 5D Classic...however...banding sucks. I've lost way too many pictures (or been limited by how much I could do to them) thanks to the damn banding...
     
  15. brettmaxwell

    brettmaxwell Mu-43 Veteran

    350
    Dec 8, 2012
    I owned both those cameras for years before switching to Nikon, I assure use the D3, D700, and D3S sensors are way ahead, and the D600 and D800 sensors are way, WAY ahead.
     
  16. pake

    pake Mu-43 All-Pro

    Oct 14, 2010
    Finland
    Teemu
    I've been underexposing ever since I learned to use E-PL1 well enough. Switching to E-M5 made a huge difference but I wondered after Pekka Potka's text if I should consider raising the ISO instead of underexposing and "fixing" it in Lightroom. Now I'm pretty confident that I will continue to underexpose. :2thumbs:

    REALLY? My g/f has a 5DII and it shows way more noise than my E-M5 in the shadows after pushing the sliders in Lightroom. I do the raw conversions (mine and hers) with Lightroom 4 and I've always had better luck with my E-M5.
     
  17. pdk42

    pdk42 One of the "Eh?" team

    Jan 11, 2013
    Leamington Spa, UK
    As an ex 5dii user, that's been my experience too.
     
  18. old.swede

    old.swede Mu-43 Rookie

    Same for me, both noise and dynamic range
     
  19. Ross the fiddler

    Ross the fiddler Mu-43 Hall of Famer

    Olympus cameras like the E3 had some banding problems but then the 12mp cameras that followed (like the E30) were better in that respect. I received some photos of a musical my daughter was in taken on a 5D & I was surprised at the noisy banded images taken at ISO 3200. I felt then my Oly E30 would have done better, but am pleased with the results I can now get out of the E-M5.
     
  20. GaryAyala

    GaryAyala Mu-43 Legend

    Jan 2, 2011
    SoCal
    With Canon, I found that proper exposure at elevated ISO's is critical. I get much less noise at ISO 3200 properly exposed than at an underexposed ISO 800.

    Gary