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View Full Version : Autofocus v Manual focus - reviewed in Phoblographer


Ricoh
15th December 2015, 01:09 AM
Some may have seen this, others possibly not. The article discusses the pros and cons of AF compared to manual focus, and I think it makes interesting reading, and some sense. Essentially the thrust of the argument is that AF is so quick it can be detrimental to composition, whereas manual focus is a more considered approach that leads to a more satisfactory outcome; it slows you down which can be beneficial.

Here's the article, 5 minutes reading, tops.

And if having read it, what do you think, do you agree?

http://thephoblographer.us3.list-manage.com/track/click?u=c936e6d50a1b870cefefb7762&id=ea198771ac&e=b8a5b56ba0

alfbranch
15th December 2015, 01:13 AM
I would say that AF can be so slow that MF can be faster in certain circumstances though some poor designs ruin MF. I hardly ever use AF for landscapes with my 12-40 or my 12-60 before it. I use AF on the 12-50 which I hate but if it worked at a decent speed and we have a focus distance indicator in the viewfinder (like Fuji and Sony) I would use MF.

Virtually all focus by wire MF is awful especially true of the 60mm f2.8 macro.

Zuiko
15th December 2015, 02:28 AM
I think it depends upon the individual photographer; Chris Gampat obviously falls into the trap of shooting quickly with little forethought when using AF just because he can. For me it is very much the opposite; not having to struggle with manual focussing frees me up to concentrate better on the scene unfolding before me and taking more care with the composition. That's not a criticism of Chris, we all have different ways of working and if focussing manually benefits him then that's the way to go.

My only caveat is that I would prefer to use manual prime lenses with a DOF scale on the lens barrel for landscapes, but with the proviso that the scale is not taken too literally. Most scales are designed to provide acceptable sharpness at the near and far extremes on a 10x8 print, but ideally I want acceptable sharpness for a 16x12 print and I don't always agree with the lens designer about what is "acceptable" anyway. For this reason, when I was using manual film cameras I used to set the focus to provide acceptable DOF for my composition using the scale, but close the aperture down at least one stop, for example to f16 when the scale indicated f11 was required. Sometimes I didn't have a small enough aperture available (or didn't want to stop the lens right down and risk overall lack of sharpness due to diffraction) and the choice had to be made whether to favour foreground or background detail.

byegad
15th December 2015, 07:14 AM
I own more MF than AF lenses anyway so he's preaching to the choir in my case.

Naughty Nigel
15th December 2015, 10:12 AM
I......so he's preaching to the choir in my case.

Do you really think choirs listen to sermons? ;)



Virtually all focus by wire MF is awful especially true of the 60mm f2.8 macro.

Not sure I agree with this (although I don't have the 60 mm Macro).

I very much like the focus by wire on my 12 ~ 40 µFT lens, which is very smooth. I also liked it on my old 14 ~ 54 Mk1.

Having said that, for me there is nothing like focusing a fast prime lens on a bright viewfinder, like my old OM's, or better still, a MF waist level finder. :)

I very rarely rely on autofocus on any camera. I may use it for initial focusing, but if I have a hand free I always adjust focus manually; if for no other reason than to be sure that the camera is focused on what I want it to be, rather than what the autofocus system would like to focus on.

However, the 'keenness' of the image magnification system on my EM5 means that I sometimes disengage autofocus altogether, as it can be difficult to find my focus point when the image is magnified by 5x, especially if the camera has decided to magnify part of the image that I am less interested in.

The image magnification is useful most of the time, but it can also be a pain. :(

OM USer
15th December 2015, 11:31 AM
Except in dim light AF is much faster than my eyes/brain. I spend so long traversing the focus to and fro about the focus point to make sure I have it absoultely spot on that the subject gives up and dies of old age before I press the shutter. If I haven't got a dioptre corrected viewfinder then its even worse as I need my higher powered reading glasses to focus on a screen thats only a foot away from my nose.

Ricoh
15th December 2015, 11:34 AM
In the interlude between the days of 35mm SLR photography and present, I started using those tiny point and shoot AF cameras (5MP IXIS and I thought it was great). Following the P+S days, I persued other hobbies - some more expensive with higher risk, but certainly demanded hand, feet and eye coordination. Later, coming back to photography I thought it natural to have AF, based on my experience of the IXIS, a natural technical evolution, as it were. Today, however, I have a slightly different view; AF has its application for quick grab shots, but recently having returned to manual 'everything': focus, exposure the lot, manual focus certainly slows me down and I'm thinking more for myself, rather handing it over, abdicating control to the camera. For me, AF takes a lot of discipline to get the composition I want. By experimentation I've turned the sound off because the focus acquisition beep was acting somewhat like a starting pistol. But it still takes discipline to ignore the visual prompt which can also act like a starting pistol.
One further aspect not covered in the blog, I find manual exposure liberating, much for the same reasons of the pros and cons of AF ~ MF.

Ricoh
15th December 2015, 11:38 AM
Except in dim light AF is much faster than my eyes/brain. I spend so long traversing the focus to and fro about the focus point to make sure I have it absoultely spot on that the subject gives up and dies of old age before I press the shutter. If I haven't got a dioptre corrected viewfinder then its even worse as I need my higher powered reading glasses to focus on a screen thats only a foot away from my nose.

Undeniably AF is faster than the human vision system, but it's a case of who has control, much like the Air France disaster off the coast of South America.

alfbranch
15th December 2015, 12:22 PM
I very much like the focus by wire on my 12 ~ 40 µFT lens, which is very smooth. I also liked it on my old 14 ~ 54 Mk1.

The image magnification is useful most of the time, but it can also be a pain. :(

Not sure either runs on FBW can you focus the 14-54 with the camera off? The 12-60 would focus with the camera off and was not FBW.

I am unsure about the 12-40 but the MF on it is great.

I never find image magnification helpful especially with macro. Focus peaking is good but a viewfinder focus scale would be brilliant.

andym
15th December 2015, 12:41 PM
Not sure either runs on FBW can you focus the 14-54 with the camera off? The 12-60 would focus with the camera off and was not FBW.


I'm fairly new to the two pro lenses ie 12-40 and 40-150 but as I use my cameras in manual focus mode 3 and auto focus with the AEL button I think in that mode the focus ring is doing FBW but if you disengage the clutch ie pull the focus ring back it's mechanically coupled.
Just sounds and feels a bit different.

Graham_of_Rainham
15th December 2015, 12:44 PM
I use manual focus a lot. Focus assistance via magnification and peaking are excellent tools, that I almost always have on.

I've grown up with manual focus and pre-focusing was often the only way to get the shot. It also increases the frame rate when needed for really fast action.

*chr

Naughty Nigel
15th December 2015, 12:49 PM
Not sure either runs on FBW can you focus the 14-54 with the camera off? The 12-60 would focus with the camera off and was not FBW.

I am unsure about the 12-40 but the MF on it is great.


The 14 ~ 54 wouldn't focus without power.

You are correct that the 12 ~ 60 would focus without power, but I didn't particularly like the feel of it.

The 12 ~ 40 will focus without power if you pull the ring back, but I prefer the feel of the FBW focusing.

Ricoh
15th December 2015, 02:02 PM
I've sold my 12~40 so can't check for myself. In manual focus mode, with the ring pulled back, does it have hard end stops at either end? (I can't see how it would work whilst also having to contend with a control loop that will under and overshoot as a matter of course, even if only to a small degree. If critically damped it would take for ever.)

And what use is a lens, as part of a system, that will focus with the camera switched off? Only useful if the 'system' is equipped with an OVF, surely.

Naughty Nigel
15th December 2015, 03:21 PM
I've sold my 12~40 so can't check for myself. In manual focus mode, with the ring pulled back, does it have hard end stops at either end? (I can't see how it would work whilst also having to contend with a control loop that will under and overshoot as a matter of course, even if only to a small degree. If critically damped it would take for ever.)

And what use is a lens, as part of a system, that will focus with the camera switched off? Only useful if the 'system' is equipped with an OVF, surely.

The 12 ~ 40 does have hard end stops when in manual focus.

I agree that mechanical focusing is fairly pointless on a camera equipped with an EVF when switched off, but it is more about the action and feel of the focusing mechanism.

Ricoh
15th December 2015, 06:30 PM
The 12 ~ 40 does have hard end stops when in manual focus.

I agree that mechanical focusing is fairly pointless on a camera equipped with an EVF when switched off, but it is more about the action and feel of the focusing mechanism.
Oh, that's a good development compared to the 12 and 17 (I've had both of these too) where the focus ring on each spin ad infinitum in the pull back mode. I'm sure the feel is better, somewhat reassuring.

alfbranch
15th December 2015, 09:33 PM
Oh, that's a good development compared to the 12 and 17 (I've had both of these too) where the focus ring on each spin ad infinitum in the pull back mode. I'm sure the feel is better, somewhat reassuring.

Has a focus scale too and it stays in the same position when you go from manual to auto focus in auto then go back manual.

Naughty Nigel
15th December 2015, 09:36 PM
Has a focus scale too and it stays in the same position when you go from manual to auto focus in auto then go back manual.

So it does. I hadn't noticed that before! :o

Ricoh
15th December 2015, 10:37 PM
You're making me so happy that I sold my copy , thank you :(

CarolE reports my ex-12-40 is working well, as I can see from her excellent photos on her flickr gallery!