Auto focus

[cliveh]

Is auto focus faster than manual focus for a given point within a scene?

 

[Dennis-B]

Yes. The A/F sensors and servos react much more quickly than your eye(s) and hands. Most people will over/under focus, trying to nail the shot. While the A/F may "hunt" a bit, it's a far faster process. While a human may trap the subject using a pre-focus, the A/F mechanism usually has a tracking feature, and as long as you hold on your subject, it will get a shot that is far more likely to be in focus.

 

[film_man]

It really depends. My Canon EOS 300 with something like a macro lens on it is slower than anything. When the light drops it just won't work. The F5 on the other hand will slam those lenses into focus when using the central focus point 99% of the time.

I am very good at manual focusing too (I use plain matte screens, no aids) and can generally focus "fast enough", as long as the lens is bright enough.

It really depends on what you are shooting and how, camera, lens type and motor, which focus sensor of which particular camera (they don't all have the same sensitivity), light, target contrast vs manual focus and plain screen, split aids and focus recompose, ageing eyes, etc.

I think where I trust the F5 more is focus tracking things that move, especially when they move towards/away from me. For static shots I'm fast enough.

But if you are talking a static scene in good light, AF is generally faster as long as you don't have a macro lens.

 

[Horatio]

I’d say it depends on the camera. My first AF SLR, a Canon Rebel, was and is fairly slow, but there’s no traditional focusing aid in the viewscreen to assist manual focus. My Nikon 8008s is slightly faster, but it offers focus assist in MF mode. My Nikon F4 is much faster, but tends to hunt in low contrast. The focus assist is a nice feature. My Canon DSLRs have fast AF.

 

[Paul Howell]

My Minolta 9 and 7 can focus much quicker than I can, unless the background is confusing in which manual focus wins.

 

[grat]

Also depends on the lens... My kit (18-125) lens for my EOS 90D is the new "nano USM" drive that Canon released, and it focuses at ridiculous speed, even when placed on a much older body.

 

[Paul Howell]

Your right grat, older Canon and Sigma SA kit lens motors are not as powerful as most current version, and the size of the in camera motors for screw drive lens also makes a difference in how fast a a lens with focus.

 

[radiant]

It depends on camera. For example Dynax 500si seems to have really unrealiable auto focus. I've been hacking the camera and shooting with it and have got into point where I just need to use manual focus (without any help, no prism). On other hand a Dynax 800si seem to have more advanced autofocus, it locks the focus more reliable. 500si is many times all over. Just when you have focused far away to shoot birds for example, it starts to go back and forth and cannot focus at all. Even on my Fuji X-T30 digital mirrorless the autofocus is sometimes pretty frustrating.

I have been pro-autofocus before but I have started to prefer manual focus. In fast situations autofocus might be better than manual but do pictures of fast situations need to be super sharp anyways?

 

[Paul Howell]

The 500si has a somewhat small motor while the 800si was for time the top of the line with a powerful motor. Other factor is the auto focus system, the 800si is more advance, the 9si more so, the 9 better yet, but not as good as the 7 which came out later than the 9.

 

[radiant]

The 500si has a somewhat small motor while the 800si was for time the top of the line with a powerful motor. Other factor is the auto focus system, the 800si is more advance, the 9si more so, the 9 better yet, but not as good as the 7 which came out later than the 9.

800si is pretty monster camera in terms of features. I've understood while 9 was more expensive / more pro, the 7 is more valued (nice display at least!).

 

[Paul Howell]

The 9 is weather sealed, stainless steel body, there was an even more expensive titanium version that has become a collector's item. The 9si was very advanced, AF is really fast, but used a set of cards for what on other makes were standard features, like a sports mode, bracketing mode. I have the 800Si and 9, I tend to take the 800si more often, the one draw back with the 9 is that the viewfinder information is dim in bright light, I live in the desert. The 7 was released after the 9 and will with all A mount lens including the Sony versions. The 9 had to sent in for a factory mode.

 

[radiant]

The 9 is weather sealed, stainless steel body, there was an even more expensive titanium version that has become a collector's item. The 9si was very advanced, AF is really fast, but used a set of cards for what on other makes were standard features, like a sports mode, bracketing mode. I have the 800Si and 9, I tend to take the 800si more often, the one draw back with the 9 is that the viewfinder information is dim in bright light, I live in the desert. The 7 was released after the 9 and will with all A mount lens including the Sony versions. The 9 had to sent in for a factory mode.

Ok, nice insight! I will keep my eyes on 7 altough I have 800si.

I bought 500si super with my summer time pay in mid-90's and that camera is still in use. I probably have some undiscovered feelings but I still like to shoot with 500si. If the autofocus wouldn't be so bad, I would be shooting much more with that. Tat is a really really good camera with 50mm prime. Lightweight, trouble free. And as the 500si isn't "serious" camera I tend to shoot quite loose with it .. and get better results than shooting with manual. Also the rewind noise of these cameras is a bit disturbing when doing street photography..

 

[halfaman]

With Canon pro bodies and L lenses AF can be so fast that I had to get used to it in the beggining. I hesitated to shoot the first days because I couldn't believe it got focus so quick. An example can be a Canon EOS 1V and a 70-200mm f/4 L IS.

 

[Paul Howell]

Late model Canon and Nikon pro lever are very fast, the F6 has very good AF, but none of these are the range of current top of line DSLR bodies, my Sony A77II is so much faster than my Minolta 9. But, the predictive AF on my A800si I think is more accurate than my Sony.

 

[radiant]

I was shooting with Dynax 500si and 800si today and it was even more obvious how much better 800si is at autofocus. I need to get another 800si that I can hack to my strange needs now. It was weird shooting normal 35mm aspect ratio after first shooting square

Auto-focus is convient but I don't find manual focusing bad at all. It depends on the situation for sure.

 

[Paul Howell]

A step from the 800si is the 9xi, not much more than a 800si, from Wiki

The Minolta 9xi was, when new in 1992, an advanced 35 mm single-lens reflex camera design. It incorporated the world's fastest autofocus system, had a maximum shutter speed of 1/12000 of a second and a 14-zone metering system