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Advice needed for dual focus setup


DanC1
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Hi all, my set up is a Sankor 16c and Nkion 1.8 or Helios 44-2 on the bmpcc. I'm struggling to get the dual focus sorted of landscape shots. I'm sure it's to do with the hyper focal distance  / aperture relationship  what distance to have the sankor focus set at. Say if it's f8 and the hyper focal distance is 50ft - ish. Do I set the Sankor to 50ft then focus the taking lens? Sometimes there's no foreground to judge peaking by and distance peaking seems poor on the bmpcc. Also when I do this it only seems to give peaking indicators when I focus the taking lens to infinity? 

Any help appreciated, my head hurts from trying to work this out. 

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This can be tricky, what i've done in the past is to focus on an object in the distance (use the zoom function on the pocket) & open up the taking lens aperture (you'll need an ND filter or just fiddle with ASA/shutter speed & then change it back). You either set the taking lens or anamorphic and fiddle with both like crazy until the object in your sights is in focus - this is why people say that dual focus is a PITA.

IMHO, for landscape shots, just set the anamorphic to infinity & then focus with the taking lens (remember to open up the aperture whilst doing this & then when you have infinity focus, stop down your lens to f8 or whatever you want).

Dual focus anamorphics take a while to get used to, but its all about practice! Just remember that you're not going to get critical focus with your taking lens stopped down & forget about focus peaking - your eyes will do a better job.

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Thanks Bioskop, I will definitely try your suggestion but I'm thinking that it may be desperate to get any clear focus wide open like that? But then I know jack shit about cameras literally. I changed the lens from the Helios to a Nikon f1.8 and worked on the assumption that the anamorphic was set to the hyperlocal distance- 50 ft wish at f8 and then focussed the taking lens. I also used a view finder which helped significantly. Here's the result from today quick time-lapse test. 

 

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I found that timelapses are difficult with the BMPCC & simply resort to using a DSLR, but that looks fine.

What I meant about focusing wide open (or there abouts), was just about getting critical focus - once you achieve that, then you stop down the taking lens. The problem with trying to focus when your taking lens is at f8 is to do with depth of field - there are more things in focus. For example, if you set your lens @ 10m & stop down your lens, then the area of what's in focus could be between 8-12m (this is not exact, but an example), as opposed to if you shot wide open, where only objects @ 10m will be in focus. So you never try to focus with a lens stopped down, simply because you'll never be able to achieve critical focus - you stop down once you achieve critical focus.

Hope that makes sense.

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