How about MFT?

 

Lumix GX85, 30mm Macro, f/4.5, 1/2500, ISO200 

I recently came across a YouTube video in defense of MFT. The footage was sarcastic and funny enough to watch, though not all the facts were accurate, which annoys me. My MFT experience is restricted to the 16MB Panasonic GX85 (also called GX80). This was actually an excellent camera, enjoyable to use, and reliable. All images on this page are from that time.

Lumix GX85, Lumix 30mm Macro, f/2.8, 1/250, ISO200

MFT stands for "micro four thirds," with a sensor half the size of the "full frame" 24x36mm sensor (FF) and a 4:3 aspect ratio instead of the usual 2:3 ratio. I wrote a lot about equivalent settings for different sensor sizes on this blog. For a reminder, let me compare two typical settings with prime lenses.

  • MFT, 25mm, f/2, 2m distance, 1/200, ISO200
  • FF, 50mm, f/4, 2m distance, 1/200, ISO800

These two will result in almost identical pictures (besides the aspect ratio, of course). Due to the smaller sensor, the angle of view is smaller on MFT, and we have to compensate with a shorter lens. To compensate for the smaller aperture, we need to increase the ISO by 2 stops. On modern cameras of both systems, the noise level will be the same. The DOF and background blur will be almost exactly the same. Even the diffraction will be the same.

For equivalence between MFT and FF, we double the focal length and the f-stop, and set the ISO to 4 times the value. 

It is worth noting that we use equivalent f-stops to get equivalent object isolation. If we use the same f-stop on both systems, we will also use the same ISO, and MFT noise will be 4 times worse. We get more DOF, however, and less background blurriness. 

We can remove noise quite effectively now. But the base ISO200 of the GX85 already shows more than I am willing to accept for a larger print. It can be smoothened in Lightroom at 50% with the default settings, so it is not yet a bigger problem. If you want fine details, you should limit the MFT ISO to 800, or even better, 400.

Connected to noise is the topic of dynamic range. MFT captures almost two stops less. If your scene has high contrast and you expose the middle tones to middle gray, whites will blow out much more easily, and shadows will be harder to recover. You should expose to the right and darken the mid-tones later, accepting the shadows in darkness.

MFT has two more noise stops, which could limit the system in low light. But you will need a fast lens on full frame to get an advantage, something like f/1.8 or f/1.2, where there is nothing much faster for MFT. For still scenes, the better IBIS on MFT can sometimes compensate for 1 or 2 stops. For moving subjects, this does not work, and you will have to accept more noise and less dynamic range.

GX85 42.5mm f/2 1/250 ISO200 vs. Z5 85mm f/5.6 1/200 ISO560

Above is an example of how similar photos can look when they are shot in RAW and developed in Lightroom. For the GX85 version, I had to do a bit more tweaking, but nothing extreme. The noise reduction needs to be higher in the Lightroom details. Below is a 100% crop, which also shows the 24MP versus 16MP resolution.

100% crop

For out-of-camera shooters, the specifics of the camera count. But for RAW, you can tweak the MFT image to look almost the same.

The full-frame has better resolution. But that depends on the lens. With the best glass in both systems, the FF will have a visible advantage. The new lenses, e.g., the ones designed for the Nikon Z system, are indeed way ahead of the older, cheaper, and smaller lenses for MFT. In most use cases, however, this will only be visible in a direct magnified comparison. In real life, good technique, a good eye, and good light matter a lot more than the gear.

Lumix GX85, 42.5mm, f/1.7, 1/100, ISO250

My favorite lenses for the GX85 were the Lumix 30mm f/2.8 OIS macro and the Lumix 42.5mm f/1.7 portrait lens. There is no doubt that you can make nice pictures with these lenses, as you see on this page. But I want to compare it to my current FF system.

Above, you see the Nikon Z5 with the 85mm f/1.8 S lens beside the Panasonic Lumix version I used for portraits. The FF setup is about twice as long and heavy. The apertures are not equivalent, because an equivalent MFT would need f/0.9. An easy-to-remember fact is that equivalent lenses have the same front diameter.

So, you will not achieve the same level of subject isolation in practice. In practice, I shoot portraits at f/2.8 on FF, and the f/1.7 lens copes quite well. The quality of these lenses is definitely not the same. Nikon has set a new standard with their S-line lenses in terms of coatings and color fringing.

Let's be realistic for the casual user. These two zooms cover approximately the same range from 24-70/80mm. The Olympus is f/2.8 and not quite equivalent to the Nikon f/4 lens, but it's close. The MFT combo is 1/3 lighter, which makes a difference. 

But the modern Olympus OM-5 II shown here has some astonishing features that the Nikon Z5 does not. Olympus is often used by macro photographers because it can quickly focus stack macro shots. The IBIS is also a lot better. The Z5 II catches up in this area, however.

The true benefit of MFT shows in the telephoto range. The 200 mm f/2.8 on the right is not quite, but almost identical to the Nikon 400 mm f/4. I cannot say much about the difference in image quality, but I would bet that the Nikon is better. It is, however, 2000g on the Z8 versus 1600g for the MFT, and it is much larger. The Nikon combo is also twice as expensive, at 8000€ versus 4000€, which might matter the most when deciding between these systems.

Lumix GX85, Lumix 42.5mm, f/2, 1/100, ISO320, 

So, there are good reasons to use either system. I recommend MFT for birders seeking a small, affordable telephoto lens. For macro shooters, the new Olympus E-M1 III is a great choice, together with a 60mm macro lens. 

For the casual user seeking a portable system for family or travel photography, the smaller MFT may also be a good choice if he or she is not into low-light photography. The compact kit zooms for MFT are not fast enough to cope with the FF kits. When I go through all my images done with the GX85, I do not find many taken in low light and hand-held. 

Lumix GX85, Lumix 42.5mm, f/2.5, 1/60, ISO800

ISO800 is equivalent to ISO3200 on FF, and that is already an emergency for me. However, the micro shot above has an equivalent f-stop of f/5 on FF, yielding a nice DOF. For micro or macro shots, a wider DOF is welcome.

Looking at the extremes, sports shooters often find themselves in insufficient light, shooting wide open at 1/2000 and ISO6400 with a telephoto lens. I don't know if MFT can cope here. The lenses are often not faster, and the noise looks two stops worse on MFT. 

Lumix GX85, Lumix 12-60 f/3.5-5.6, 12mm, f/6.3, ISO200

For landscapes, the wide DOF is also welcome. Note that f/6.3 is equivalent to f/13 with the same diffraction.

In summary, choosing the system is difficult. If you are ready to dive into photography, you will likely select FF anyway. Instead of buying all the lenses for your camera, consider having a second body in MFT format for carry-around, macros, or birding.

A collection of almost equivalent 50mm setups



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