DV Info Net - New moving ground glass mechanism

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Quote:

Originally Posted by Joel Aaron

Sometimes F2.8, F4 or F8 makes the prettiest bokeh and/or tells the story best in a given environment. Sometimes F16 does best. There are a ZILLION examples of shots in FEATURE films using VERY deep DOF because that's what told the story best for that scene. DP's are at F4 or f5.6 a lot of the time. Those are still SHALLOW apertures that blur the background beautifully. The DPs still have to pull focus, block and can't get lazy at those apertures. Pull out your DOF chart and take a look at a 50mm at F5.6 and tell me how "lazy" a DP can be about pulling focus. (Here - I'll help: focused at 5 ft the near focus is 4.6' and far is 5.6'). A FOOT! If the actor takes one step closer they are going out of focus at 5.6. And the closer they get to the camera the more shallow the DOF becomes. At 2 feet there's a whopping one inch.

I thought I'd finally respond to this, since I've been testing this more lately.

I'd say with any of these 35mm adapters/imagers, if you're wanting to take the lens down to f/16 or even f/8, in order to increase your depth of field for the look you're after, or for ease of focusing, your image is going to turn to mud, haze, and blotches. Ya gotta remember we're dealing with the illusion of shooting on film. The very nature of what we're doing with these contraptions is working in the art of magic. So it's important to know what boundaries you have to work with in order to create your illusion. I will most likely not go past f/5, for the sake of image quality.

If I really needed a lot of depth of field, I'd take the rig off and use the stock lens. So, yes this all means that your 35mm imager work will be requiring some high maintenance focusing for sure. It's a real eye opening experience to me. I'm up for the challenge for the rewards it brings. Most in depth discussions on these boards, regarding 35mm imagers, raise the issue, should keep raising the issue, and should *not* exclude the issue, of the need to get really aggressive, dedicated, and ambitious about focusing.

As Dan said, ideally we would be shooting on film. I'll add that an alternative in the future will be relatively affordable 35mm sized sensor digital cams.

Until then, it still stands that it's an amazing time where we can get the look we're after, to some degree, using relatively inexpensive technology, that is now available.

Quote:

Originally Posted by Steev Dinkins

Amen Brother!

That's a good point Steev. Stopping down the lens will defeat the purpose of shallow DOF in the first place. I’m not sure I would shoot wide open for softness reasons, but a F2.8 to F4 seems to be about the most reasonable working range to keep the DOF shallow. At F8 and up you might as well use the stock zoom and save you the trouble.

Quote:

Originally Posted by Michael Maier

At F8 and up you might as well use the stock zoom and save you the trouble.

Stock video lenses are more like F22 than F8.

The reality appears to be that F8 is just not doable on these adapters. That solves that - it's simply a limitation.

I never intended this to be about lazy focusing. It's an asthetic thing. I find F1.4 WAY too shallow in many instances. I hate most of "teacup" tests people post where the front edge of the cup is in focus and the back edge of the cup is already out of focus and everything behind that looks a like a 100 pixel blur. That looks like crap for anything but teacups and thimbles. I'll probably be F4 to 5.6 most of the time.