Manual or Auto Focus
Manual focus or auto focus is a question that comes up all the time. From new photographers to even the most experienced. First let me say what I use. I only have manual glass. I use manual lenses for photography because I like it. Does that make them better. No. I think it is important to know the pros and cons of both. Now I use them because it is good for what I do. At the same time a photographer that uses manual lenses because of some weird status or image rather then because he needs it is no better then the person who uses auto lenses because they don’t know how to focus. Sadly a lot of people picking one side or the other are the same people who fight over digital or film. Is one better then the other? Well try to have the film enthusiast edit a photograph or have the digital guy take a 2 week long exposure with out running out of batteries. “The picture on the above right is of me pulling focus for a Fox News video called Home Grown Terror shot in early 2011, with a manual lens on a jib hooked up to servos”
Why do I use manual? Well the biggest reason is because my job that pays the bills requires me to use manual lenses. I am a film maker by profession and a photographer on the side. I have an extensive lens collection of all manual glass. Let me list the reasons why I use manual glass.
1: Focus Throw
Throw is how far you spin the lens to focus from the minimum distance to the maximum distance. The reason you want a lot of throw on the lens when doing video is because it is easier to pull focus and keep the subject in focus and track with them while they move. It is also better to hook up a follow focus to a manual lens rather then an auto lens. I can’t tell you how many times i’ve seen people ruin a shot by using an auto lens wide open and trying to pull focus with an inch of lens throw.
2: Manual f-stop
Aside from video and photography I use my
lenses for time-lapse photography. Not just a time-lapse here and there. I have shot around an hour of
time lapses which is a lot of shutter counts. I’ve broken a few cameras in these last couple years just wearing out there shutters from time-lapse photography. So on a auto lens when you take a picture a lot happens. Your lens diaphragm closes down then the camera takes the picture and then it opens up again. The reason it does this is to focus more exact with the f-stop wide open. So when it stops down you know for sure the subject is in focus. The reason you do not want your f-stop to keep opening and closing is because when you have 5-20 aperture blades rubbing against each other for over 200,000 pictures it can start to cause problems. So on my manual lenses I focus then stop down to where I need them and they just stay there. Does this mean you can not make a time-lapse video if you have any auto lens. No. It just means if you keep making time-lapse videos it might have problems in the future. Those problems can be from metal dust from the blades deteriorating or sticky blades making the time-lapse look flickery because the exposures were all different.
Manual lenses are heavier. Now I like weight to a camera. I think it helps me take sharper pictures at a slower shutter speed. It also helps with hand held video to have a bigger camera. Ask anyone who takes video with a gopro to how shaky or un usable the footage was. “Hint if you want smooth video with a gopro over crank it to 60fps”
Now this is the part that gets interesting. the exact same three reasons above for being pro manual focus are for being pro auto focus.
1: Lens throw
If I want to shoot something fast pace like a sports event I am going to wish I had a auto focus lens at times because of the short focus throw. Auto lenses have shorter focus throws to get in focus quicker.
2: Auto f-stop
It is nice and easy not to have to focus then stop down when taking pictures. Although on my lenses I have a switch to open up the aperture blade quickly and focus and click the switch again to stop back down.
3: some people prefer lighter lenses. If you are going to go back packing and it will save weight to bring one light lens rather then 10 heavy prime manual lenses.
I hope this post does not frustrate anyone too much. Basically the choice is up to you. Ideally both would be good. I can’t afford to get two of every lens. With time-lapse and video the choice was easy for me to go manual. I was going to talk about price, however manual lenses can be more expensive then auto lenses. They also can get pretty cheap as well. After all there are far more used manual lenses then auto. What are your thoughts?