Zone Focusing

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#1
For Zone Focusing.

Sorry if it has already been asked and even more sorry, if it was me that asked it. But I did do a search, but nothing what I was after, came up.
Setting the camera to manual focus. On the Nikon 50mm 1.8D, if I set the lens to f/8 and the lens ring to 0.45, will everything be in focus, or should the focus ring be at the other end? Sorry for such a basic question, but my brain does not retain information anymore.
 
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#2
There's a table on the internet somewhere that shows DoF by lens and by aperture and by focus distance.
 
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#3
Depends on the sensor size.

Go here: https://www.dofmaster.com/dofjs.html

Plug in your camera, lens and aperture. Ignore the subject distance, scroll down a bit to where it says "focus at the hyperfoal distance", xxft

Rotate the focussing ring on your lens until it matches that distance.

E.g., Nikon D7000, 50mm lens at f8
Hyperfocal distance is 51ft. Set the focus distance on the lens ring to 51ft. Everything from 25ft to infinity will be sharp.

Hyperfocal focussing on a 50mm lens with a crop camera at f8 probably isn't a great idea. Your best bet is to set the focus ring to whatever distance your subjects are at (assuming street, so 6-8ft?) rather than the hyperfocal distance.

If you want "everything in focus", you generally need a wider lens and/or narrower aperture. On a crop camera, something like 16mm is much better. A 16mm lens at f8 has a hyperfocal distance of 3ft [on the same D7000], which makes everything from 2ft to infinity sharp.

greqergrqeggreq.JPG
 
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#4
It sounds like you are asking about HyperFocus and not ZoneFocus...
ZoneFocus is more pre-focusing on a spot so that the subject will be sharp when it gets to that point... the purpose being to alleviate AF speed/accuracy issues as well as tracking/timing issues. It's basically a manual version of TrapFocusing.

HyperFocus is used to maximize the depth of field... I use the SWAG method:
For a FF/35mm camera start with the lens set to f/11 (f/16 for APS, f/22 for 4/3).
Then divide the FL by 10 (or just drop the last digit) and square the number... i.e. 50mm becomes 5, and 5x5=25.
25ft is the hyperfocal distance where a 50mm lens at f/11 on FF camera should be focused. And when focused to 25ft everything from 1/2 that distance (12ft) to infinity will be w/in the DOF as shown by a calculator.
And then, if you change the aperture by two stops the hyperfocal distance changes by two; i.e. f/5.6=50ft, f/22=12ft (one stop is in-between, but not exactly in the middle; approx .4).

Now, this is just a SWAG (i.e. it is less accurate if you have a 1.7x APS) and there are other potential errors in using HyperFocus... like where exactly 25ft is. So guess long... If you focus beyond the HFD you loose a little near DOF. If you focus short of the HFD you gain a little near DOF, but you loose a lot from the far DOF.

That said, 95% of the time you are much better off just focusing on the most important element in the scene (IMO)...
 
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#5
Depends on the sensor size.

Go here: https://www.dofmaster.com/dofjs.html

Plug in your camera, lens and aperture. Ignore the subject distance, scroll down a bit to where it says "focus at the hyperfoal distance", xxft

Rotate the focussing ring on your lens until it matches that distance.

E.g., Nikon D7000, 50mm lens at f8
Hyperfocal distance is 51ft. Set the focus distance on the lens ring to 51ft. Everything from 25ft to infinity will be sharp.

Hyperfocal focussing on a 50mm lens with a crop camera at f8 probably isn't a great idea. Your best bet is to set the focus ring to whatever distance your subjects are at (assuming street, so 6-8ft?) rather than the hyperfocal distance.

If you want "everything in focus", you generally need a wider lens and/or narrower aperture. On a crop camera, something like 16mm is much better. A 16mm lens at f8 has a hyperfocal distance of 3ft [on the same D7000], which makes everything from 2ft to infinity sharp.

View attachment 267902
It sounds like you are asking about HyperFocus and not ZoneFocus...
ZoneFocus is more pre-focusing on a spot so that the subject will be sharp when it gets to that point... the purpose being to alleviate AF speed/accuracy issues as well as tracking/timing issues. It's basically a manual version of TrapFocusing.

HyperFocus is used to maximize the depth of field... I use the SWAG method:
For a FF/35mm camera start with the lens set to f/11 (f/16 for APS).
Then divide the FL by 10 (or just drop the last digit) and square the number... i.e. 50mm becomes 5, and 5x5=25.
25ft is the hyperfocal distance where a 50mm lens at f/11 on FF camera should be focused. And when focused to 25ft everything from 1/2 that distance (12ft) to infinity will be w/in the DOF as shown by a calculator.
And then, if you change the aperture by two stops the hyperfocal distance changes by two stops i.e. f/5.6=50ft, f/22=12ft (one stop is in-between, but not exactly in the middle).

Now, this is just a SWAG (i.e. it is less accurate if you have a 1.7x APS) and there are other potential errors in using HyperFocus... like where exactly 25ft is. So guess long... If you focus beyond the HFD you loose a little near DOF. If you focus short of the HFD you gain a little near DOF, but you loose a lot from the far DOF.

That said, 95% of the time you are much better off just focusing on the most important element in the scene (IMO)...
Sorry I should have also said, it is a 35mm film camera.

So it is HyperFocus and not ZoneFocus. Ok reading up on it.
 
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#6
If you look on the lens, you'll see the infinity symbol. Move that so it's next to your chosen aperture. The number opposite the aperture on the other side is the minimum distance and your lens is set for the hyperfocal distance.

Google "how to set the hyperfocal distance with a manual lens" for much better explanation.
 
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#7
Some lenses have marks on them to show where the focus range is that lines up with the distance window based on aperture set. Quite common on "old" film lenses.
We went digital, we gained some stuff, we lost some stuff.
 
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#8
Sorry I should have also said, it is a 35mm film camera.

So it is HyperFocus and not ZoneFocus. Ok reading up on it.
If it is a film camera, does the lens have a DOF scale on it? The aperture numbers next to the focus indicator shown in this picture...

Lens_aperture_side.jpg

The lens is set to f/11 and the DOF scale indicates it is ~ 1m to 3m. If the lens were set to f/22 it would be ~ .8m to infinity.
 
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#9
If it is a film camera, does the lens have a DOF scale on it? The aperture numbers next to the focus indicator shown in this picture...

View attachment 267916

The lens is set to f/11 and the DOF scale indicates it is ~ 1m to just over 2m. If the lens were at f/22 it would be ~ .8m to infinity.
DoF scale is wrong way round :)
As is aperture ring.
 
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#11
That'll do nicely.
 
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#12
@sk66 this is my lens here.
The aperture numbers next to the distance scale are the DOF scale... but it's a fairly modern AF lens and it's fairly useless (due to the short focus throw). It also probably doesn't have a hard/accurate infinity stop. Also note that in order to use AF with that lens the aperture ring has to be set to f/22, but you need to use the exposure setting with the DOF scale instead... I would still SWAG it (or not bother).

Lens_aperture_side.jpg
 
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#13
The aperture numbers next to the distance scale are the DOF scale... but it's a fairly modern AF lens and it's fairly useless (due to the short focus throw). It also probably doesn't have a hard/accurate infinity stop. Also note that in order to use AF with that lens the aperture ring has to be set to f/22, but you need to use the exposure setting on the DOF scale... I would still SWAG it.
Yes I have been using it on my Nikon F60 film camera, and yes set f/22, and aperture is chosen by rear dial. Camera only has a single centre focus point, and not that good for street shooting. So I was thinking of turning AF off, and using manual HyperFocus what I thought was ZoneFocus.
 
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#14
Yes I have been using it on my Nikon F60 film camera, and yes set f/22, and aperture is chosen by rear dial. Camera only has a single centre focus point, and not that good for street shooting. So I was thinking of turning AF off, and using manual HyperFocus what I thought was ZoneFocus.
The problem is that being w/in the DOF does not actually mean sharp; it means "acceptably sharp" based on a rather weak standard... You are intentionally misfocusing the subject in order to gain more DOF.

It's probably also worth mentioning that a FF lens can be mounted on an APS camera (or adapted to 4/3, etc) but the DOF scale will be entirely wrong.
 
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#15
The problem is that being w/in the DOF does not actually mean sharp; it means "acceptably sharp" based on a rather weak standard... You are intentionally misfocusing the subject in order to gain more DOF.

It's probably also worth mentioning that a FF lens can be mounted on an APS camera (or adapted to 4/3, etc) but the DOF scale will be entirely wrong.
Thanks for the reply.

I will get out and experiment (y)
 
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#16
Yes I have been using it on my Nikon F60 film camera, and yes set f/22, and aperture is chosen by rear dial. Camera only has a single centre focus point, and not that good for street shooting. So I was thinking of turning AF off, and using manual HyperFocus what I thought was ZoneFocus.
50mm is getting a little long for hyperfocal technique IMO.

(proper) Zone focusing is likely to be more useful for street, especially if you are resorting to f/22 on a 50mm. If the light is not strong sun and and you are not using a quite fast film, you are likely to needing fairly slow shutter speeds, and you will start to experience diffraction softening, all of which will negate the sharpness gains you may have made with everything technically in focus. It’s possible to make these things part of your style, but I get the impression you’re not really at that point yet.

You can get adequate depth of field for most street situations with f/8. Be aware of whereabouts your focal distance is to your subject (or where they will be) and roughly adjust accordingly.

Unfortunately, an AF lens is never going to be great for manual focus work, there is just too little throw for accuracy and the focus rings are usually quite small and hard to use. I use manual focus primes 98% of the time, mostly on digital, but also still with film.

Things get much more comfy for DoF for street if you step down to a 35mm or perhaps wider lens. You can broadly set it at around 4.5m and be confident most of the scene will be in focus at f/8.
 
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#17
50mm is getting a little long for hyperfocal technique IMO.

(proper) Zone focusing is likely to be more useful for street, especially if you are resorting to f/22 on a 50mm. If the light is not strong sun and and you are not using a quite fast film, you are likely to needing fairly slow shutter speeds, and you will start to experience diffraction softening, all of which will negate the sharpness gains you may have made with everything technically in focus. It’s possible to make these things part of your style, but I get the impression you’re not really at that point yet.

You can get adequate depth of field for most street situations with f/8. Be aware of whereabouts your focal distance is to your subject (or where they will be) and roughly adjust accordingly.

Unfortunately, an AF lens is never going to be great for manual focus work, there is just too little throw for accuracy and the focus rings are usually quite small and hard to use. I use manual focus primes 98% of the time, mostly on digital, but also still with film.

Things get much more comfy for DoF for street if you step down to a 35mm or perhaps wider lens. You can broadly set it at around 4.5m and be confident most of the scene will be in focus at f/8.

IMG_2802.JPG

Just dug the old Tamron 28-300mm out from the back of the cupboard, this lens may be more suitable then. It does have the focusing scale, so this lens may be better than the 50mm 1.8D prime.
 
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#19
Steven hi,
I have to ask, what's the SWAG method?
 
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#20
Things get much more comfy for DoF for street if you step down to a 35mm or perhaps wider lens. You can broadly set it at around 4.5m and be confident most of the scene will be in focus at f/8.
That's because 4.5m (15ft) is very close to the HFD @ f/8 (~17ft)... i.e. you're still using hyperfocus and not zone focus.

The difference being that zone focus places the DOF (whatever it is) around the point of actual focus, which is placed where you are anticipating the subject to be... I.e. zone focus trades DOF (things near/far being within it) for greater subject sharpness.
 
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jonbeeza
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#22
It doesn't have a DOF scale, but you don't really need it.
Using the SWAG method, the hyperfocal distance at 28mm f/11 is just under 9ft (i.e. 3x3=9)... I'd use 8ft.
@sk66 Thanks for taking the time to explain all that. I will give it a whirl in a few days. (y)
 
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#23
That's because 4.5m (15ft) is very close to the HFD @ f/8 (~17ft)... i.e. you're still using hyperfocus and not zone focus.

The difference being that zone focus places the DOF (whatever it is) around the point of actual focus, which is placed where you are anticipating the subject to be... I.e. zone focus trades DOF (things near/far being within it) for greater subject sharpness.
It’s not quite hyperfocal (2.5m to 35m now I check) but yes, that’s why I suggested swapping to a 35mm lens as it’s easier to manage
 
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#24
HyperFocus is used to maximize the depth of field... I use the SWAG method:
For a FF/35mm camera start with the lens set to f/11 (f/16 for APS, f/22 for 4/3).
Just a small point but shouldn't that be FF f11 and (if you can set them to this) APS-C f7 and MFT f5 or there abouts. Sorry if that's already been said.
 
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#25
The only reason I want to try zone focus or HyperFocus , or whatever the correct term may be, is because the camera only has one focus point, right bang in the centre. If I wanted to place the main focus point of the object in one third of the frame, the focus point misses that point, and focuses on something much further back, resulting in the main object of interest out of focus. So I thought to get around that, simply get everything in focus. If I did want the main focus to be in one third, I would have to simply get in much closer. Focus and recompose is not something I am good at, as I can't manage to keep the camera the same distance, at all times.
 
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#26
Just a small point but shouldn't that be FF f11 and (if you can set them to this) APS-C f7 and MFT f5 or there abouts. Sorry if that's already been said.
No, if the only thing changed is the sensor size then smaller sensors deliver less DOF (because the smaller "negative" has to be enlarged more). So smaller sensors have to be stopped down farther in order to have the same starting point DOF/HFD.
It's the same "equivalence factor" as affects everything else; 1 stop for 1.5x APS and 2 stops for 2x M4/3.
 
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The only reason I want to try zone focus or HyperFocus , or whatever the correct term may be, is because the camera only has one focus point, right bang in the centre. If I wanted to place the main focus point of the object in one third of the frame, the focus point misses that point, and focuses on something much further back, resulting in the main object of interest out of focus. So I thought to get around that, simply get everything in focus. If I did want the main focus to be in one third, I would have to simply get in much closer. Focus and recompose is not something I am good at, as I can't manage to keep the camera the same distance, at all times.
I would have thought that focus and recompose is much easier to learn than hyperfocal focusing (at least with a modern autofocus lens with no aperture scale). The two systems will also produce different results. Hyperfocal focusing always gives you a large depth of field while with focus and recompose you can have any depth of field you choose.
 
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#28
I would have thought that focus and recompose is much easier to learn than hyperfocal focusing (at least with a modern autofocus lens with no aperture scale). The two systems will also produce different results. Hyperfocal focusing always gives you a large depth of field while with focus and recompose you can have any depth of field you choose.
I am using an old film camera, it does not have AF-L.
 
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#29
I have no idea as to what AF-L might be. Use manual focus to get your subject in focus and you have no need to worry about focus and recompose or hyperfocal focusing.
 
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#30
I am using an old film camera, it does not have AF-L.
Focus/recompose is essentially zone focus.
I.e. you prefocus on where the subject is and hope it is near the plane of focus and w/in the DOF when the image is taken... and it can result in the same kind of focus errors (the subject not being at the plane of focus when the shot is recomposed)
 
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#31
Focus/recompose is essentially zone focus.
I.e. you prefocus on where the subject is and hope it is near the plane of focus and w/in the DOF when the image is taken... and it can result in the same kind of focus errors (the subject not being at the plane of focus when the shot is recomposed)

Thanks for the explanation, (y)
 
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#32
No, if the only thing changed is the sensor size then smaller sensors deliver less DOF (because the smaller "negative" has to be enlarged more). So smaller sensors have to be stopped down farther in order to have the same starting point DOF/HFD.
It's the same "equivalence factor" as affects everything else; 1 stop for 1.5x APS and 2 stops for 2x M4/3.
Ah, I thought you were taking a picture with FF and duplicating it with smaller formats. I assume from all this you're keeping the same lens across formats?

I use zone sometimes as it's an easy way of taking pictures quickly with manual lenses, especially action ones.

Another method the op might want to think about is Merklinger method as it seems to work and you don't need DoF tables or too much brain work. I'm sure Googling will lead to a good explanation.

That said, 95% of the time you are much better off just focusing on the most important element in the scene (IMO)...
Yup.
 
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#33
For Zone Focusing.

Sorry if it has already been asked and even more sorry, if it was me that asked it. But I did do a search, but nothing what I was after, came up.
Setting the camera to manual focus. On the Nikon 50mm 1.8D, if I set the lens to f/8 and the lens ring to 0.45, will everything be in focus, or should the focus ring be at the other end? Sorry for such a basic question, but my brain does not retain information anymore.
What are you trying to zone focus for ? You have an AF camera. Zone focus is for manual only lenses.
 
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#34
What are you trying to zone focus for ? You have an AF camera. Zone focus is for manual only lenses.

The only reason I want to try zone focus or HyperFocus , or whatever the correct term may be, is because the camera only has one focus point, right bang in the centre. If I wanted to place the main focus point of the object in one third of the frame, the focus point misses that point, and focuses on something much further back, resulting in the main object of interest out of focus. So I thought to get around that, simply get everything in focus. If I did want the main focus to be in one third, I would have to simply get in much closer. Focus and recompose is not something I am good at, as I can't manage to keep the camera the same distance, at all times.
For the reason above, in an earlier post. :)
 
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#36
Ah, I thought you were taking a picture with FF and duplicating it with smaller formats. I assume from all this you're keeping the same lens across formats?
Well, actually the FL is the variable in the initial calculation... i.e. a 50mm =5x5 =25ft HFD, and a 30mm =3x3 =9ft HFD.
After you have the initial HFD you can vary the aperture and calculate the change... i.e. from f/11 to f/5.6 (2 stops) the HFD doubles.
 
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#37
Another method the op might want to think about is Merklinger method as it seems to work and you don't need DoF tables or too much brain work. I'm sure Googling will lead to a good explanation.
I had to look this one up... Merklinger's method is simply a variation on my statement that it is typically best to just focus on the subject. This is particularly true when the subject is beyond the HFD.

For example, take the 30mm @ f/11 on FF. The SWAG HFD is 9ft (8.8ft by calculator). And when focused at HFD the DOF extends from ~4.5ft to ∞ . But if your subject is at 50ft it will not be maximally sharp.
If instead you use the 30mm f/11 on FF and focus on your subject at 50ft, the DOF now extends from 7.5ft to infinity and your subject is perfectly sharp. You have shifted the zone of sharpness backwards, loosing a little at the near end. The calculators make it seem that you do not gain anything in the distance because you cannot have more than infinity, but that's not really true. Things in the distance become closer to being truly in focus, as opposed to acceptably in focus (w/in the DOF). No matter how far away the subject is, the near DOF point is never greater than the HFD (9ft)... therefore;
If instead you were to focus at infinity (Merklinger) you shift the zone even farther back, now you loose even more near focus and the DOF is at 9ft extending to ∞, but your subject is again no longer in actual focus.

There are very few times where there is a real benefit to having the primary subject of a scene in less focus, so that very distant/near details are more in focus.
 
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#38
I had to look this one up... Merklinger's method is simply a variation on my statement that it is typically best to just focus on the subject. This is particularly true when the subject is beyond the HFD.

For example, take the 30mm @ f/11 on FF. The SWAG HFD is 9ft (8.8ft by calculator). And when focused at HFD the DOF extends from ~4.5ft to ∞ . But if your subject is at 50ft it will not be maximally sharp.
If instead you use the 30mm f/11 on FF and focus on your subject at 50ft the DOF extends from 7.5ft to infinity and your subject is perfectly sharp. You have shifted the zone of sharpness backwards, loosing a little at the near end. The calculators make it seem that you do not gain anything in the distance because you cannot have more than infinity, but that's not really true. Things in the distance become closer to being truly in focus, as opposed to acceptably in focus (w/in the DOF).
If instead you were to focus at infinity (Merklinger) you shift the zone even farther back, now you loose even more near focus, and your subject is again no longer in actual focus.

There are very few times where there is a real benefit to having the primary subject of a scene in less focus, so that very distant/near details are more in focus.
I only have one focus point on my old film camera, and it is right in the centre. It means everything I take a photo of, has to be right in the centre of the frame. Sometimes it looks awkward, as the subject would have looked better in the one third portion of the frame. If I were to position my subject on the rule of thirds line, the focus point misses them.
 
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#39
I only have one focus point on my old film camera, and it is right in the centre. It means everything I take a photo of, has to be right in the centre of the frame. Sometimes it looks awkward, as the subject would have looked better in the one third portion of the frame. If I were to position my subject on the rule of thirds line, the focus point misses them.
I understand your issue... I've explained Hyper focus, Infinity focus, and Zone focus. All are manual focus techniques, so we can ignore the focus point issue.

First, let me explain that DOField (DOFi) calculators are not a lot of help here... because they only tell you the zone of acceptable focus. They tell you nothing about how sharp/unsharp things will actually be inside/outside of the DOFi.

What we are actually concerned with is the DOFocus (DOFo) at the image/sensor plane... which is the source of the resulting DOFi.
Shorter FL's and narrower apertures increase the DOFo, so if your goal is to maximize the DOFo you need to use such lenses/apertures. So lets go back to the 30mm @ f/11 on your FF camera (your 28mm zoom). With an inability to autofocus (or manually focus through the viewfinder accurately) you have the three manual focus choices discussed. They break down like this:

*You can use Hyper Focus if there are things very close to the camera that you care more about than actual subject sharpness... things at distances less than 9ft (the 30mm HFD)... DOFi = 4.5ft-∞

*Or you can use infinity focus (Merklinger) when there are things very far away that you care more about than actual subject sharpness... DOFi = 9ft-∞

*Or you can zone focus (pre-focus) at the distance where you expect your subject to be... DOFi begins somewhere between 4.5-9ft and extends to ∞. But your subject will be closer to the point of maximum sharpness. The best case here is to actually focus on the subject, but that is not an option.

In all three cases the DOFo at the sensor is the same, you are simply adjusting where parts of the scene are w/in it. And your results will vary accordingly/notably even though a DOF calculator makes them seem extremely similar.

Chances are that you are using wider apertures trying to keep higher SS's (fixed film ISO). That is not going to work nearly as well; because wider apertures cause a significant reduction in the DOFocus, even though they have a less notable effect on the resulting DOField.
 
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#40
I understand your issue... I've explained Hyper focus, Infinity focus, and Zone focus. All are manual focus techniques, so we can ignore the focus point issue.

First, let me explain that DOField (DOFi) calculators are not a lot of help here... because they only tell you the zone of acceptable focus. They tell you nothing about how sharp/unsharp things will actually be inside/outside of the DOFi.

What we are actually concerned with is the DOFocus (DOFo) at the sensor plane... which is the source of the resulting DOFi.
Shorter FL's and narrower apertures increase the DOFo, so if your goal is to maximize the DOFo you need to use such lenses/apertures. So lets go back to the 30mm @ f/11 on your FF camera (your 28mm zoom). With an inability to autofocus (or manually focus through the viewfinder accurately) you have the three manual focus choices discussed. They break down like this:

*You can use Hyper Focus if there are things very close to the camera that you care more about than actual subject sharpness... things at distances less than 9ft (the 30mm HFD)... DOFi = 4.5ft-∞

*Or you can use infinity focus (Merklinger) when there are things very far away that you care more about than actual subject sharpness... DOFi = 9ft-∞

*Or you can zone focus (pre-focus) at the distance where you expect your subject to be... DOFi begins somewhere between 4.5-9ft and extends to ∞. But your subject will be closer to the point of maximum sharpness. The best case here is to actually focus on the subject, but that is not an option.

In all three cases the DOFo at the sensor is the same, you are simply adjusting which parts of the scene are w/in it. And your results will vary accordingly/notably even though a DOF calculator makes them seem extremely similar.

Chances are that you are using wider apertures trying to keep higher SS's (fixed film ISO). That is not going to work nearly as well; because wider apertures cause a significant reduction in the DOFocus, even though they have a less notable effect on the resulting DOField.
I have taken on board what you said, thanks for posting all that in-depth stuff. (y)
 
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