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Old November 24th, 2004, 09:39 AM   #1
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What to do for deeper DOF?

I gather that shooting f11 or higher would cause undesirable noise from the ground glass.

If you want to shoot shallow sometimes and deeper other times, what would be an option?
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Old November 24th, 2004, 10:16 AM   #2
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As you'll read in many of these posts, shooting above f5.6 may begin introducing the ground glass in your images. With the new mini35 (400 series units) this problem apparently has been resolved. I have the 300 series so I can't say for certain anything about the 400 series.

How large/deep are you talking about shooting?

One option is to use the stock lens of the dv cam instead of the mini35 for those shots where you need deep DOF, I haven't done this yet but know you would have to perform some grain matching in post, perhaps using Grain Surgery, Cinelook or MagicBullet.
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Old November 24th, 2004, 11:38 AM   #3
 
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One suggestion is to intentionally backfocus enough to bring in the background without sending the subject out of focus.
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Old November 24th, 2004, 11:58 AM   #4
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The answer to the question really all depends on where the subjects are placed, the desired perspective and desired framing of the object (ie. CU, WIDE, ECU... etc..)

With a 28mm lens set to f11 the subject has to be approx 7.5 feet away from the camera lens so that the subject and everything behind it is in focus together - thus creating a huge depth of field. (Infinite in this example).

The problem is what size in the frame will the subject be at 7.5 feet from the camera lens? It obviously depends on the size of the subject. So if it's a person maybe it's okay, but if it's a car or a small animal - what will you end up with?

Backfocus on the mini35? I don't think it can be done.
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Old November 24th, 2004, 12:07 PM   #5
 
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oops...yeah, you're right, sorry...duh!
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Old November 24th, 2004, 12:11 PM   #6
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I mean there is a focus on the mini35 itself, but I've only mainly used that so the camera CCD can focus on the final output screen of the mini35.

Just use the DV cam stock lens and save yourself all the grief.

There's no reason the footage can't be matched, I wouldn't even hesitate doing this myself if I had to for a particular scene. For the last shoot I was on I even had my XL2 Canon lens in a bag just incase.
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Old November 24th, 2004, 02:35 PM   #7
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I agree with Dennis. The amount of work, hardware and $ involved with the Mini35 is only relevant if you intend to shoot below an f 5.6 most of the time. But there are occasions where a deep stop is desirable such as when using a particularly telephoto lens with the subject moving quickly towards you, thus making follow focus very difficult; or for a deep focus look to a scene. By far the easiest way to deal with this is by pulling the Mini and shooting with a standard lens. If retaining the same lens optics is considered absolutely critical and a telephoto lens is desired (and you are shooting on an XL series camera), the XL to PL mount adaptor could be used in these instances.

To avoid having to match the looks between non-Mini and Mini footage, I would recommend avoiding jumping between the two within a complete scene, or at the very least between two shots that have a similar background or direction. You could probably get away with shooting one side of a conversation with the Mini and not having it for the reverse, but I wouldn't want to shoot a master on the Mini and not have it for the closeups that see the same background, etc.

Remember that you will have a good 1.5 stop difference between shooting modes, so if you start a scene without the Mini, make sure you have enough exposure to continue it once it is mounted.
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Old November 24th, 2004, 02:44 PM   #8
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Hey Charles, have you found the "effective" ASA of the mini35 with XL1 or XL2 to be about 250? I know there's really no such thing with CCD's... but this is what it worked out to for me when I metered it.
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Old November 27th, 2004, 09:00 AM   #9
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Dennis:

I haven't shot much with the XL2 yet, but I think I used to rate the XL1s at 160-200. Depends on the vintage of Mini35 also, the newer ones are a bit faster.
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