There's Nothing Magical About Medium Format Depth Of Field

Shallow depth-of-field is often cited as being a key part of the 'medium format look' but is that actually true? We compared a Fujifilm GFX and Sony a7R IV for a closer look at the effect of format size on depth-of-field to find out.

Click here if you want to know why we're multiplying the f-number by the crop factor:

Click here to find out what else medium format does (and doesn't) offer, over other formats:

0:00 - Intro
0:30 - What affects depth of field?
1:04 - Equivalency
4:00 - Telephoto test
5:48 - Wide angle test
6:36 - Telephoto results
7:21 - Wide angle results
7:45 - The wrap

Enormous thanks to our friends at The Camera Store for providing gear

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[andyandy]

The old real medium format was 6x6 cm (56 x 56 mm) and equipped with a standard lens of 80mm 2.8 it was very hard to get the same look on FF because you would need to use 35mm lens (and crop it to the square) and have aperture of 1.0 that generally does not exist for such a lens.
Also, if you have FF with 35 1.4 and you want to get the same look in apsc you would need 23mm 0.9 that generally also doesn't exist.
The thing is that medium format is now usually 44 x 33 and there are not many fast lenses, so in many cases FF have smaller DoF now. But if you use film 6x6 it's very difficult to replicate using FF.

[highlander]

I love how optimistic Chris sounded about the comment section

[davewagner]

I always assumed that the misconception about medium format DOF was due to people not understanding the changing focal lengths/stops between the various formats. One sure edge though to MF is the details and colors that can be resolved with those massive sensors. Great video!

[yyhsupergroovegear]

From my experience the depth of field debate comes from the full framers about smaller sensor sizes. I don't often hear the debate from the APS-C users about Micro 4/3s or medium formatters about any other smaller sensor sizes.

[OutdoorMemories]

How about showing the fastest lens available for each and seeing the difference? Lens potential is also important

[donschiffer]

If similar aperture lenses were available medium format would have a real advantage. But the fact that none of the lenses have more than an f2 aperture (and most are 2.8+) eliminates most of that advantage.

[OldGirlPhotography]

I suspect that part of the problem is while many of us recognize and apply the appropriate multiplication factor to focal length for comparison, we don't apply it to aperture. So we compare a crop sensor setup at f/2.8 to a full frame or medium format setup also at f/2.8. Of course then there is a difference.

[Macjohn]

I’ve worked with medium and large formats over the years and I’ve said the same things as you did in this video. The problem is that someone comes up with their own opinion and if that person happens to be a “pro” photographer with a following on FB or YouTube, everyone watching is convinced that statement is gospel. The same things go for buzz words. Someone coins a phrase or keeps repeating a particular word, then everyone else follows suit. I’m tired of hearing about bokeh, micro contrast and other buzz words that make people think they know what they’re talking about. Would like to see you debunk these, too.

[thecaveofthedead]

Much comes down to how easy a given focal length can be built to a given big aperture and then what field of view it has in a given format. An 85mm f1.4 is a real sweet spot on full-frame that can be bought cheaply to get a shallow depth of field that an APSC camera will need usually a very expensive lens to reach - a 56 f0.95 or so. Similarly, the Pentax 67 with its standard 105 f2.4 lens. You can make a 105 f2.5 cheaply. But a 50mm f1.1 or so on full-frame is not a cheap lens - at least until recently.

So it's what people typically use that creates much of the impression of the differences. Pretty much anyone with a Pentax 67 will have that 105 f2.4 which will totally isolate a full body shot from the background. But such images are rare on 35mm and basically non-existent on APSC - even though they're achievable with all formats.

What's really strange is the way you reviewers often don't change your language to reflect this - talking about a 56 f1.2 as a 'bokeh beast' or whatever on APSC while not giving the same enthusiasm to an 85mm f1.8 on full frame.

[grantmedical]

Just to add my 2 cents:
M43 42.5mm f/1.2
= APC 57mm f/1.6
= 35mm 85mm f/2.4
= Medium Format 110mm f/3

ALL 4 SENSOR SIZES CAN GIVE PERFECTLY ADEQUATE DEPTH OF FIELD FOR PROFESSIONAL PORTRAITURE!

[andrewward]

Medium format is about tonality not depth of field.

[MattEMaddock]

Totally agree and points very well made. I have used all 3 types of sensor extensively and now settled on APS-C Fujifilm and Hasselblad MF [Had GFX cameras, don’t care for them much]. Unless you’re printing huge there really isn’t enough difference to justify almost anyone moving to MF. Where there is a BIG difference is when I’m shooting interiors, which makes up the majority of my work. When shooting a room at 16mm on APS-C or 30mm on MF for the same FOV the difference in scene compression/distortion is huge and very noticeable. Even noticeable over 24mm on FF, and that’s why I shoot MF. If I wasn’t doing high end interiors APS-C has so many advantages and why I still have an extensive set of APS-C kit. 99% of people don’t need anything else, in fact shooting MF is generally an absolute pain - huge files, huge heavy cameras/lenses, mostly need to shoot tripod (yes IBIS is fine, but MF lenses don’t have fast apertures so you’re generally shooting with slower shutter speeds, often beyond the usefulness of IBIS) - not to mention the cost!

[salpjs]

It may go without saying but you boys did a lot of work to produce this video study. Not that all your videos take a great deal of work, but this was downright teacher level scientific prep. Two thumb up.

[galachiev]

FF users about APS-C: ha-ha noisy crop
FF users about Medium Format: size doesn’t matter!!!

[yizhe]

Depth of Field (DOF) can be the same DOF if one adjusts (e.g., physical distance to the objects, lens, aperture) accordingly with the given camera in hands. The real factor is the *physical size* of the object projection on the sensor. To a certain extent, the physically larger the size of the projection is, the better the image quality is. Medium format camera has a physically larger sensor, allowing a physically larger size of projection for the same composition, thus having a higher *upper limit* on image quality.

[losmalqueridos]

This video is awesome & it proves a great point. The point being that digital medium format is a money grab. You're not getting that 6X6 or 6X7 film medium format look. That Pentax & Mamiya medium format cameras give a very distinct & unique look. I dont think it's possible to get that look unless you use the Brenizer method in post. Also I recently ran into a gfx shooter while I was shooting some street photography & we sparked up a conversation. He was suffering from buyers remorse & was missing his XT3. He told me he fell into that hype of a bigger sensor equals better photos. I told him not to feel bad because these companies spend big bucks to make us feel like we need all these super expensive cameras & lenses. That's why I love you guys. Y'all dont hype the gear up like other youtube influencers. Keep up the great work guys.

[JeffDiffner]

It’s funny that in every comparison video it’s always about shooting wide open and how there’s little difference in the images but no one does the other end of the spectrum. When shooting with my 645, especially dealing with strobes, I would routinely be at f/11 or higher. If working outside, f/16. Even at f/16 (needed for the exposure because my sync speed was set), medium format offers a decent focus fall off at portrait distances that you would not get with 35mm or APS-C sensors. The basic problem with your premise is that shutter speed and sensitivity are inconsequential

[feraudyh]

The depth of field is governed by one formula:

DOF = 2*u²*N*c/(f²)
where
* is multiplication.
u is the distance to subject
N is the f-number
c is the circle of confusion
and f is the focal length

That's all you need to know.

[GordoFriman]

Hello. thank you for your really precise and mathematically correct test, its very clear and well done. However, There is something not really fair on it, and is that you are comparing Full frame vs the aps-c of medium format. If you want to go fair you need to compare only aps-c medium format vs aps-c 35mm sensors. Or... at least a full 645 sensor vs full 35mm sensor.

Said this. There are actual and noticeable diferences when you compare medium format (not even talking about 6x7 or bigger..) and smaller format. Actually you guys showed the difference at 6:58, where the 56mm shows all kinds of lens limitations and issues compared to a cleaner, softer and more perfect image on the 110mm. And this is, because the medium format lens is working more "relaxed": is a longer focal leght with smaller aperture, but has the advantage that is focusing at the same distance than the shorter focal lenght lens (so, even easier for the MF lens)

So, what happens with even smaller formats? all is focus transitional zone + the inconveniences of super short focal lenght. if you added micro four thirds to the comparison the degradation would have bee even more noticeable.

To me there is big misunderstanding about medium format and depth of field: Its not going to blur more, but its going to blur better. Its not going to make your subject pop more because its has less depth of field, But because it can cut out the subject in the same way as a telephoto lens does, but showing more image on the sides. Its not going to be clearer and sharper because the lens its better, but because the in-focus zone has "harder" boundaries making things go from super sharp to instant soft blur as transition zone is smaller.

1 sentence summary: Medium format is higher quality because it has the perfomance properties of a thelephoto lens combined with the field of view of a wider angle lens.

The "misterious" medium format "look" is, and always was: "A wide angle telephoto image." And this is what is terribly hard for people to understand. They notice, but dont know exactly what is going on.

[bjorn]

0:35 a fourth factor affecting depth of field is the focal plane. It is often not that important when you're photographing at a distance but it is much more important when doing macro photography, so I thought it deserves a mention... :)