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GH4 UHD & C4K Hyperfocal Distance

Started Jun 29, 2018 | Discussions
GrayJones New Member • Posts: 2
GH4 UHD & C4K Hyperfocal Distance

I know that on the GH4, the crop factor in UHD and C4K is greater than in 1080p. I see very different crop values online, but let's say for this example the UHD crop factor is 2.3x.

My question is, how does that affect the hyperfocal distance?

For instance, I have a 12mm lens (24mm equivalent in 1080p). In UHD, assuming a crop factor of 2.3 instead of 2.0, that lens now becomes a 27.6mm equivalent in 35mm terms, or 13.8mm as a M43 lens.

Should I be calculating the hyperfocal distance as if it were a 13.8mm lens? Or still 12mm, even though it is acting like a 13.8mm lens?

Panasonic Lumix DMC-GH4
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hindesite Veteran Member • Posts: 4,893
Re: GH4 UHD & C4K Hyperfocal Distance

GrayJones wrote:

I know that on the GH4, the crop factor in UHD and C4K is greater than in 1080p. I see very different crop values online, but let's say for this example the UHD crop factor is 2.3x.

My question is, how does that affect the hyperfocal distance?

For instance, I have a 12mm lens (24mm equivalent in 1080p). In UHD, assuming a crop factor of 2.3 instead of 2.0, that lens now becomes a 27.6mm equivalent in 35mm terms, or 13.8mm as a M43 lens.

Should I be calculating the hyperfocal distance as if it were a 13.8mm lens? Or still 12mm, even though it is acting like a 13.8mm lens?

Does it really matter, in practical terms?

In addition, do you also need to recalculate the hyperfocal distance at each focal distance of the lens you are using (some lens have significantly differing focal lengths at different focal distances, though not approaching your crop factor example).

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OP GrayJones New Member • Posts: 2
Re: GH4 UHD & C4K Hyperfocal Distance

Yes, for this particular project I need the absolute maximum depth of field with a 12mm lens, and need to calculate the precise hyperfocal distance to do so. I need to know if the changed crop factor in UHD/C4K affect that hyperfocal distance or not.

LingoDingo Senior Member • Posts: 1,769
Re: GH4 UHD & C4K Hyperfocal Distance
1

GrayJones wrote:

Should I be calculating the hyperfocal distance as if it were a 13.8mm lens? Or still 12mm, even though it is acting like a 13.8mm lens?

Cropping into the lens image does NOT change the focal length of the lens, so you should still treat it as a 12mm lens.

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