Low Light Noise Performance – Can m43 Embarrass Full Frame?


Conventional wisdom states that in low light situations m43 cameras are inferior to their full frame counterparts because more noise is evident at higher ISO settings. This argument is flawed because, for a given amount of light, it assumes both camera types would need to be set with the same shutter, aperture and (hence) ISO.

For a particular ISO, there is not question that noise tends to increase as the sensor size (and hence pixel dimensions) shrink. Some claim that a m43 sensor is about “2 stops” noisier than the full frame equivalent. As such, a m43 sensor at ISO800 would be expected to produce noise roughly on par with a full frame sensor at ISO3200. This is simply physics and can be accepted as true.

That all being said….

Technologies found in many m43 cameras, and the sensor size itself,  enable significantly lower ISO settings than that on a full frame camera in the same situation. In fact, we will see scenarios where ISO can be reduced 2 stops or more to effectively eliminate the “2 stop noise advantage” offered by full frame sensors.

Case 1 – Technology removes the shakes

Irrespective of sensor size, many lenses and some bodies incorporate image stabilization technologies. Not all technologies are equally effective, however. Anyone doing a bit of research will reach the conclusion that Olympus’ IBIS (in body image stabilization) is leaps ahead of the in-lens stabilization technologies found in (many, but not all) larger sensors lenses (in fact, it is also considered more effective than the Sony A7ii IBIS).

How effective is the Olympus’ stabilization? Take a look at the photo below hand-held at 1/6s. The absence of any sign of camera shake is quite incredible. It is even more amazing because it was taken with a 75mm lens (150mm equivalent angle of view on full frame bodies).

Apartment in KrakowApartment in Krakow – m.Zuiko 75mm 1:1.8 – 1/6s @ 1.8 ISO800 HAND HELD

Two things two consider:

  • With a full frame camera and a 150mm lens would anyone expect to get a decently sharp photo at 1/6s? Even with an in-lens stabilizer, I suspect it would be difficult to  achieve the same results at 1/25s – two stops faster. If the full frame lens has no stabilizer, then the golden rule of thumb dictates 1/150s minimum shutter to avoid camera shake which will require an ISO increase of about 4.5 stops
  • Second, I am not aware of many full frame lenses offering f1.8 at 150mm. If you are lucky, f2.8 is the max. In order to compensate, another 1 stop ISO increase is required.

In summary, the IBIS technology in Olympus cameras is key to sharp photos several stops slower than that of full frame counterparts. To compensate, the full frame camera will require several stops higher ISO. Though a lessor argument, m43 offers some telephoto primes with extremely wide apertures that simply do not exist in larger formats. This further allows lower ISO settings. The full frame noise advantage is essentially lost. 

And, the technology is improving – though perhaps lucky, this  Russian photographer’s blog documents sharp handheld photos at 15s using the new OM-D E-M1ii and 12-100mm f4.0 lens (with its own stabilization).

Case 2 – More depth of field can be good

Razor-thin depth of field lovers correctly state that m43 photos have 2 stops increase in depth of field compared to shooting with a full framed camera at the same aperture for identical angle of views. So, an m43 camera with a 25mm lens at f2.0 will have the same depth of field as a full frame camera with a 50mm lens at f4.0 (2 stops smaller).

Irrespective of whether you like razor-thin depth of field or not (I certainly do not), take a look at the photo below. It simply will not work with less depth of field, and could probably benefit from more.

Apartment in KrakowYoshi – m.Zuiko 12-40mm 1:2.8 – 32mm 1/40s @ f8.0 ISO 1600

Even with my m43 body, a relatively small f8.0 aperture was used at 32mm. On a full frame body, f16 would be required to maintain the same depth of field (i.e. two stops slower). To compensate, either the shutter is reduced to 1/10s or the ISO is increased to 6400. Lowering the shutter speed is not an option. Even if the camera was on a tripod to reduce shake, the photo is of a cat and cats move. Therefore, the ISO on a full frame camera would need to be increased 2 stops to provide the same depth of field necessary for this photo. Again, the full frame noise advantage is essentially lost.

In conclusion…

For a given ISO setting m43 sensors tend to have about 2 stops more noise than full frame sensors. However, technologies found in m43 bodies and the 2 stop increase in depth of field resulting from the reduced sensor size create situation where ISO can be lowered for m43 cameras thereby eliminating much, if not all of the full frame noise advantage.

Do these capabilities carry over in all situations? Certainly not – sports photography, or anything requiring fast shutter speeds to freeze action, will put m43 at a disadvantage. If the subject is relatively stationary, or if it requires significant depth of field then m43 can be a very compelling option for low light photography. Of course, do not forget the m43 size and weight advantage when carrying your camera around during dark nights!

Does m43 really embarrass full frame in low light situations? I wouldn’t go that far, but certainly I would give m43 more consideration than it has thus far received for low light photography.

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2 thoughts on “Low Light Noise Performance – Can m43 Embarrass Full Frame?

  1. Philippe Pascal

    This is essentially why more and more landscape photographers switch to m43.
    And even more with the new High Resolution Mode.

    They use base ISO, and near f8 aperture. Dynamic is more than enough (m43 sensors get dynamic around 10 years old FF sensor), same about color domain.
    They don’t need ISO bump. And it is lighter.

    Same about wildlife. Until someone need faster phase focus for fast moving animals, they will get an amazing result with very bright 43/m43 lenses.
    There are gems, like 43 Olympus 150mm f2. Put it on Phase Focus E-M1 with an adapter, and you will take breathtaking photos. And not expansive second hand.
    Who else get a 300mm f2 equivalent ? And you can use it wide open. Not so evident with bigger sensors APS-C/FF Canikon. Even at “equivalent” DOF/aperture f4.
    I had the FF syndrome. But since my second hand E-M1, i think i left this way 😉
    I will rush on second hand lenses. I already got the amazing 50-200mm f2.8-3.5 non-SWD.

    My next purchase is going to be a focal reducer and some legacy 85mm f1.4.
    So i will get around 170mm f1.4 and 120mm f1.0/1.2 with focal reducer…and IBIS 😀

    Reply
    1. tomlismer Post author

      I am very much curious of results with a focus reducer. The whole concept is quite interesting. I am not sure of your experiences with a straight-through adaptor, but I do find it really depends on the lens. My Nikkor AF-D 85mm 1.8 works quite well, as does my 135 2.8 AIS. My 200mm f4 AI produces strangley huge amounts of chromatic abberation with rather low contrast. It is more strange because with film, it is quite a good lens.

      Focus peaking is something that I have been quite impressed with. I use red, and it makes it very easy to focus manually.

      Reply

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