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HELP camera choice for a commercial: minimun depth of field - portraits exterior daylight

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wich camera should I choose for a commercial where I need portaits with critical focus on the eye and minimun depth of field?

 

I am inclined to full frame... but wanted the maximun latitude possible... so ...

 

what about 1d-C versus 5D? do I get quite more latitude with canon log... am I right?

 

and one doubt: I I use the 1D-C on APS-H wich is not full frame... what is really happening? do I lost the critical depth of field or I just crop the image?

 

in the beginning I was thinking of the C-300 but because I want that sense of tilt&shift focus on the portrait...I thought about depth of field with full frame and compact primes 1.4

 

 

this is the kind of look I am searching for, but with the maximun dynamic range possible because I will be shooting exterior and I haven't got nice experiences on the white clipping with 5D

 

THANKS IN ADVANCE

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oh, sorry. it was just because I wanted to resolve my doubt as soon as possible. SORRY. I understand.

 

can you help me with my doubt? or do you know someone who could solve it?

 

thankx in advance

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Depending how long of a lens you can get on, you can use many many cameras-- another option which would be possibly interesting would be 1.3X anamorphic lenses on a 4x3 Alexa.

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There is a 1.5-stop difference between full-frame and APS-C/Super-35 in terms of effective depth of field, so using an f/1.4 lens wide-open on an Alexa, for example, would be similar to using an f/2.0-2.8 split stop on a lens on a Canon 5D, assuming you match field of view and distance to subject.

 

So you can't get as shallow a focus on a Super-35 camera compared to an f/1.4 lens on a full-frame camera unless you can find lenses that are much faster than an f/1.4, which are rare.

 

Just depends on whether maximum shallow focus is more important to you than maximum dynamic range, right now you can't have both. However, there is the Magic Lantern hack for the Canon 5D MkIII that allows raw recording, which would give you more dynamic range.

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David, sorry... I quite don't get it...

 

if the 1D is a native full frame camera... Even if I shoot on 1080 (wich is suposed to be APS-H size, not APS-C size)... that should mean that I crop the image formed on the chip, but not affect the depth of field...

 

isn't it the same situation that if I would use a 35mm lens on a 16mm camera? wouldn't that produce a big picture on the focal plane with narrow depth of field, but cropped by the 16mm window size????

 

Am I wrong???? is there any picture that explain in black and white why the cropping affect the depth of field...???

 

Do you understand my point???

 

tricky issue...

 

hmmmm

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The framing will have changed. Using the same focal length at the same distance the DOF will be pretty similar on 35mm and 16mm (according to the tables 16mm may even have a tad less), however, the framing of the subject will be different..

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yes, the frame will have change... but I am interested here in depth of field to get the sense of the video I posted...

 

and to get that sense of depth of field with no renouncing to c-log dynamic range of 1D-C... (my thought is that I am not sure if I a right assuming that 1D-c on 1080 APS-H mode will get me the full frame depth of field only with the image or angle of view cropped

 

you see my point? I need the narrowest depth of field possible with the maximun dynamic range... and have to choose among medium cameras (can's afford the big big ones)

 

thankx

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I suspect you can achieve something similar using Super 35 with the lens at f1.4. A 50mm lens has a DOF of about 1 inch at 4ft at f1.4.

If you're renting the camera you should visit the rental house and run a quick test.

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Cropping itself doesn't change the depth of field, other than it may change the circle of confusion figure used to calculate the depth of field if the cropped image is then enlarged to match an uncropped image when comparing depth of field... but cropping changes the field of view, which then usually means you then change the focal length to compensate when comparing images -- in other words, as a starting point, you'd want to compare the same composition, same field of view, same subject size and distance to subject, when comparing depth of field differences.

 

This is only a rough approximation but generally the crop factor is the same as the difference in depth of field in terms of f-stop adjustment once you match field of view and distance to subject. In other words, if you are comparing two cameras and one has a sensor that is twice as wide (if you want to compare just horizontal view rather than diagonal just to make the math easier) then if the distance to the subject is the same, then camera with the sensor that is half as wide would need a lens with a focal length that was half that of the larger sensor, a 2X crop factor. So a 25mm lens, let's say, on the smaller sensor camera versus a 50mm lens on the larger sensor camera to get the same image more or less. And at the same distance, you'd have to stop down the 50mm lens by two f-stops to match the depth of field of the 25mm lens -- so let's say that the exposure was f/2.8 on the 25mm lens, it would have to be an f/5.6 on the 50mm lens that was on the larger sensor camera to get a similar depth of field.

 

Again, these are all ballpark figures, not precise calculations...

 

So if the difference between a sensor image area that is 24mm wide (Super-35 / APS-C) and one that is 36mm wide (full-frame) is 1.5X, then the practical difference in depth of field is 1.5 stops. Once you matched field of view (by using a focal length that was 1.5X shorter on the APS-C camera) and distance to subject to get the same composition and subject size more or less, you'd have to open up the APS-C camera by 1.5-stops to match the depth of field of the full-frame camera image.

 

Now some of these DSLR's crop the sensor when recording HD video, so you'd have to use the actual recorded dimensions to calculate the difference in depth of field, but APS-H is obviously smaller than full-frame 35mm.

 

This isn't rocket science and I wouldn't get too obsessed over the math of it. The real question is whether the depth of field of an f/1.4 lens on a Super-35 camera is shallow-focus enough for you, or if you need to find the new Vantage f/1.1 lenses. And let's say you went to a full-frame camera like the 5D but only could find f/2.0 lenses for it -- then you are only talking about a 1/2 stop difference in depth of field over an f/1.4 lens on an Alexa or something -- is that really a big deal or not?

 

Personally shooting wide-open on a f/1.4 lens on the Alexa would give you both shallow focus and a wide dynamic range, so the question is whether you really need even less depth of field by going to a Canon 5D with an f/1.4 lens (probably a still lens) and lose the extra dynamic range plus ease of focus pulling on cinema lenses. Of course, the 5D with still lenses is probably a lot cheaper. And as I said, there is a raw hack from Magic Lantern for the Canon 5D that would give you more dynamic range if you want to deal with that.

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