I need to re-learn aperture and DOF

[Martin Ocando]

Having shot smaller sensors for 20 years, since moving from film to DSLR in 2005, I forgot that aperture and DOF is a creative parameter. For example, in MFT, shooting at f/2.8 is like f/5.6 FF DOF, so very little subject isolation. But stopping down, approaching f/8 and you are bordering refraction limits. So I used to shoot wide open all the time and completely forgot about aperture.

Muscle memory is making me do the same, and I'm ending with quite shallow DOF and forgetting to stop down to get more things into focus. Shot some flowers today hoping to test my just arrived 70-200mm f/4 OSS II only to find almost nothing in focus.

I guess I'll have to study DOF tables again.

 

[ahaslett]

Also you are using a 61Mpix sensor. When making a shot that actually depends on that much resolution, you are boxed into blur in the plane of critical focus vs blur from being out of the plane of critical focus.

f6.3 is about as far as i want to go in MFT for landscape. F11 is as far for my A7Riv.

At the other end, you can get shallow DoF at quite some distance with a 135/2 or 35/1.2.

The principles are the same irrespective of sensor size, just x2 or x4 for ISO.

Andrew

 

[Lichtspiel]

On the other hand, it's great fun to get some good subject separation and "3D-ness" out of cheap f1.8 primes!

But yes, don't hesitate to stop down much more and more often than when shooting with MFT. I still tend to be a bit more on the open side when it comes to landscape, and accordingly end up with OOF foreground or background. Which is often not a bad thing.

It gets even more extreme with close-up and macro...

 

[Rod McD]

Hi,

Yes, I've been through the same journey. Years ago I used to use medium format and 4x5" film and then migrated to digital through APSC and finally FF. Each film/sensor size imposes its own limitations on us. FF certainly offers less DOF than MFT or APSC.

To be technically accurate, sensor size does not appear in the DOF formulae. DOF tables show a decrease in DOF when you 'click' to increase sensor size by changing the default Circle of Confusion - COC - which is about viewing magnification. We really notice the impact on DOF when we increase sensor size because we use lenses of longer FL to achieve any given angle of view. In moving from MFT or APSC to FF, we have to use longer lenses, increase magnification and therefore lose DOF.

Some people choose FF to achieve less DOF because that works well for their style. For others, eg if you happen to like landscape, macro or telephoto work, like me, it presents a challenge. Shallower DOF actually makes it more difficult. I end up juggling how far to stop down to gain sufficient DOF but avoid diffraction. I regularly end up using f8 and f11 with a 24mm lens to obtain deep enough DOF for some landscapes. Inadequate DOF will cause soft images far faster than the early impacts of diffraction. If in doubt, bracket your aperture, focusing distance and the resulting DOF.

One possible solution is stacking but it doesn't work for all subjects and involves more time and complexity in post. Still another is to use movements, but they're not straightforward either.

All the best with it....

Cheers, Rod

 

[SeeingSomeThingsMissingMany]

I had m42 lenses on ff & m4/3 : my 5dmk2 and Epl7 this year; A7 and Gx80 in 2019; my Kodak slrC 35mm dslr and Ep1 around 2010-2012.

Manual legacy glass easiest fastest way I found, just setting aperture for more dof less dof according to taste : how want the photograph to turn out.

With live view it's a piece of cake

--
Photography after all is interplay of light alongside perspective.

 

[MikeInOr]

A shallow DOF (depth of field) can really set the main subject off in a well crafted photo. But it seems like many photographers buy a fast lens then want to use an incredibly shallow DOF for EVERY SHOT!!!! It just drives me crazy some times. I was just looking at some photos with a shallow DOF for no reason in another forum on this board. :-(

Yes, full frame enables shallower DOF than smaller sensors. The trick is to learn when to take advantage of the shallow DOF and when to opt for a much deeper DOF.

I remember my boss showing me photos of his cat from his new f/1.4 lens on his Leica. The cats eyes were in perfect focus with its ears and nose very blurred because of the wide open F/1.4 lens. He was so proud of his new lens and cat photographs I didn't have the heart to tell him how awful the photos looked.

The people that claim their phones with tiny sensors are just as capable as a high end ILC have no understanding of DOF. So I just smile and agree with them and honestly believe their is no difference for them.

 

[ray_burnimage]

Also you are using a 61Mpix sensor. When making a shot that actually depends on that much resolution, you are boxed into blur in the plane of critical focus vs blur from being out of the plane of critical focus.

f6.3 is about as far as i want to go in MFT for landscape. F11 is as far for my A7Riv.

At the other end, you can get shallow DoF at quite some distance with a 135/2 or 35/1.2.

The principles are the same irrespective of sensor size, just x2 or x4 for ISO.

Andrew

Yep, x2 is a simple way to work for dof rather than bothering so much with tables. So 2.8 you now shoot at 5.6 etc for equivalent results after coming from m43 to FF.

 

[poipoipoi_2016]

A shallow DOF (depth of field) can really set the main subject off in a well crafted photo. But it seems like many photographers buy a fast lens then want to use an incredibly shallow DOF for EVERY SHOT!!!! It just drives me crazy some times. I was just looking at some photos with a shallow DOF for no reason in another forum on this board. :-(

Yes, full frame enables shallower DOF than smaller sensors. The trick is to learn when to take advantage of the shallow DOF and when to opt for a much deeper DOF.

I remember my boss showing me photos of his cat from his new f/1.4 lens on his Leica. The cats eyes were in perfect focus with its ears and nose very blurred because of the wide open F/1.4 lens. He was so proud of his new lens and cat photographs I didn't have the heart to tell him how awful the photos looked.

The people that claim their phones with tiny sensors are just as capable as a high end ILC have no understanding of DOF. So I just smile and agree with them and honestly believe their is no difference for them.

Of course, then you're into the sports photographer's dilemma.

• Stop wide open and use that to buy shutter speed so your moving subject isn't moving in the frame (... as much).
• You're indoors so you have bad light and you're already ISO 1000 or whatever so stopping down sends that into even deeper issues with ISO quality and noise reduction. Especially on dogs. Dogs have fur.
• Stop down and spend it in shutter speed and you very quickly figure out just how fast you needed to go because your subject is a moving animal.

It's one of a few places I go "So your phone lies to you and in this place they are useful lies"