Rack focus with Olympus 12mm, 45mm, Panasonic 25mm

[Ros Dok]

Hello,

I wonder if anyone tried to do a rack focus shot with the Olympus 12mm 2.0, 45mm 1.8 and/or Panasonic 25mm 1.4. Also: anyone tried a follow focus with these lenses? Not planning to buy one right now because it's too expensive, but maybe later. I'm using the cheap Trudeau jar opener trick for now. ;)

Thinking about buying the three lenses. I have the 20mm pancake and Kipon adapter with Canon EF 50mm 1.4 but they're not really working for me. I use my GH2 50-50 for video and stills and don't like the Canon because I can't use AF (for stills) and with the pancake in video it's nearly impossible to focus from something in the front to the back. It's so small I can't attach the jar opener (or FF) and have to swing it all the way around anyway.

Thank you!

[Angelo Ucciferri]

I just bought a Follow Focus for my GH2 - and I have the Panny 25mm and Oly 12mm. I'll report back with an update once I try it out. I realize that these are electronic focus lenses and might not have the best FF response. But I also have some old manual Pentax lenses I plan on using with it.

Angelo

[Angelo Ucciferri]

I am currently testing a follow focus with my Olympus 12mm & Panasonic 25mm.

I knew the Panasonic 25mm was not going to work well, since it's electronic focus with an infinite spinning focus ring. This did not work well with the follow focus and the focus kept changing depending on how fast your turned the knob and I often ran out of lens gear.

However my biggest surprise came when I tried the Olympus 12mm which I though had a mechanical focus that engaged when you slide the focus ring back towards the camera body. It works really well mechanically with a follow focus - and the focus ring feels solid. However, upon closer inspection of my footage - I see that the focus is STEPPING. So a nice slow rack focus ends up stepping through various focus points.

Has anyone else heard of such an issue with the Olympus 12mm? Maybe the lens mechanics functions like a manual focus lens - but it is in fact an electronic stepper motor. Very disappointing, especially considering the whopping cost of the lens.

Thanks,
Angelo

[Michael Pekic]

Thanks for your description, Angelo.
I've been considering the Olympus 12mm to exchange my Panasonic 14mm, but I'm wondering in which scenes would you rack focus on a wide angle lens?

I don't have a follow focus yet, but I tried my Olympus 45mm to rack focus yesterday and it is very nice! Love it. No stepping or the like Angelo described with the Olympus 12mm and Panasonic 25mm.

[Jeff Harper]

I've not experienced the "stepping" issue with any lens but I've not used a follow focus either.

[Angelo Ucciferri]

Thanks for the follow up Michael and Jeff,

After a lot of testing and finding a discussion on another forum (definitive info: Manual focusing the 12mm f/2 - Micro Four Thirds User Forum), I learned what the problem is.

The Olympus does unfortunately have stepped focus when the focus ring is slid in to manual mode (pulling the ring towards the camera body). If you are doing slow rack focuses, you will absolutely see the lens step through focus points - especially on close up detail shots with a shallow dof.

However, when the lens ring is pushed forward, and the camera body is set to manual focus, the stepping goes away and the rack focus becomes smooth. Unfortunately, in this mode, the lens goes in to an electronic focus mode similar to the Panny 25mm - the focus point changes depending on the speed at which you are turning the follow focus. So you can not repeat rack focuses and you will run out of lens gear.

So those are your 2 options for rack focusing the 12mm with a follow focus - experience ugly stepping focus points when the lens is in manual focus - or deal with the inconsistent "focus by wire" control when the body is in manual focus. Contrary to the appearance of the manual focus ring - this is a full electronic focus lens which is useable but not ideal for a follow focus rig.

To answer your question Michael, there are a lot of scenarios where you would want to rack focus on a wide angle lens - especially when working with subjects very close to you. For example, if you are focusing on a subject a 2 feet away and you want to rack focus to another subject 10+ feet away. Or even just between 2 close focus points on a table in front of you. The Oly 12mm has very shallow DOF at f2 and rack focuses are very dramatic. It is possible to use it with a FF in body-manual mode, but you have to learn how to work the FF in a way where you periodically reset the focus range by quickly snapping the focus so you can gain a larger range to then slowly move between. Alternatively, you can set the lens to autofocus, adjust the FF so your lens gear is in the optimal position, then put the lens back in to body-manual mode and use the FF. It's possible, just annoying and slow.

One solution may be to use a friction FF so you don't have to worry about running out of lens gear - like this one: http://www.bhphotovideo.com/c/product/827322-REG/SHAPE_FFCLIC_Friction_Gear_Follow_Focus.html
I sprung for the Redrock Micro Blue for the awesome resettable focus "memory" stop markers. But that is a geared system. Although I may be able to retrofit it with a friction focus wheel. I'll have to look in to it. However, I have been using it with a fast Sigma 18-50 2.8 Pentax lens - which has real mechanical manual focus. That has really been working out great!

Thanks,
Angelo

[Jeff Harper]

That stinks about the 12mm, sorry to hear it. I use the lens' manual focus rarely.

The SLR magic 12mm might be the best bet for your work.

[Bruce Foreman]

Originally Posted by Ros Dok

Hello,
I wonder if anyone tried to do a rack focus shot with the Olympus 12mm 2.0, 45mm 1.8 and/or Panasonic 25mm 1.4.

Only one of those 3 I have is the 45mm f1.8, playing around with it today on a recently acquired GH2 I tried using the touchscreen focusing (in movie mode) and a "rack" focus from one subject to another does work. Camera should be on a fairly solid tripod because it works best if the "touch" on the screen is fairly "firm". Also each subject should have enough contrast so the focus "locks" without "hunting".

There is a slight delay between the touch and the actual focus change but if you "anticipate" it you can get a decent "rack focus". Should also work with the Lumix 20mm f1.7.

I wouldn't trust trying to do it with a follow focus due to the "focus by wire" effect.

[Angelo Ucciferri]

Originally Posted by Bruce Foreman

Only one of those 3 I have is the 45mm f1.8, playing around with it today on a recently acquired GH2 I tried using the touchscreen focusing (in movie mode) and a "rack" focus from one subject to another does work. Camera should be on a fairly solid tripod because it works best if the "touch" on the screen is fairly "firm". Also each subject should have enough contrast so the focus "locks" without "hunting".

There is a slight delay between the touch and the actual focus change but if you "anticipate" it you can get a decent "rack focus". Should also work with the Lumix 20mm f1.7.

I wouldn't trust trying to do it with a follow focus due to the "focus by wire" effect.

Thanks Bruce,

I think the "rack focus" that Ros Dok and I were referring to is controlled "cinema style" focus shift from one subject to the next - only achievable with a follow focus, or very steady hand control on the lens directly. The touchscreen focusing you are referring to will jump the focus - but it is more "utility" than "cinematic". I don't think the touchscreen focus jumps looks good live, but that is just my opinion.

Angelo