Choosing the Right Camera and Lens for your KMU-100

Choosing the Right Camera and Lens for your KMU-100

Choosing the Right Camera and Lens for your KMU-100

Nov 03 2020 | KMU-100
Choosing the Right Camera
and Lens for your KMU-100

First, consider the following:
-The distance between camera and talent
-The amount of horizontal space to capture in the shot
If shooting in a house of worship or auditorium with minimal/ambient lighting, we suggest setting the lens wide open and slightly zoomed in.
A Wider Depth Of Field (aka DOF)
A shallow DOF puts subjects out of focus when they move closer or further away from original focus points. For subjects that walk forwards and backwards, a wider DOF is critical.

Wider depth of field is best achieved with wide lenses, from 10mm to 35mm. They can capture wider DOF and even infinity focus when used correctly. Prime lenses are the best at achieving less shallow DOF. More light also helps to shoot at smaller apertures, which increases DOF. 

Wide lenses that are fast are the answer.

Sensor Size and Crop Factor
The problem with Canon EF mounts on cameras with significant crop factors, like the BMD URSA and URSA Mini, is that Canon and other manufacturers are selling full frame lenses designed for purchase by photographers with full frame cameras.

These cameras are suited with EF mounts to increase the amount of available high quality lenses, but the crop factor is a shortcoming.

We recommend a lens with f/2.8 aperture or lower, 12mm - 24mm (for a roughly 20-40mm equivalent on full frame 35mm lenses)
Choosing The Best Focal Length-Do they need a wide angle lens (10mm too crazy? 15mm with crop factor)?
Depending on how far the camera is from subjects, you will need a wider lens or one that is more punched in.

With the crop factor of 1.7x at UHD on the URSA, a 10mm or 15mm could work just fine depending on how close the camera is to the stage.

An expensive lens is necessary to have a pure rectangular image with no distortion. 
Positioning The Camera
Pull the lens back to full wide, and move the camera until everything is in frame. This will achieve the most depth of field. Any variable zoom lens that is zoomed in or a telephoto lens will have less depth of field. 
-Do they need a lens with a smaller aperture (not f/2.0)?
                If a lens is wide open or within 1 stop of its minimum aperture it will achieve a very shallow depth of field. 

After everything is in frame at full wide on the lens, adjust the lens to an aperture at least 1-2 stops above the minimum, then add more light to subjects in frame until everything is exposed properly at a 180 degree shutter, ISO 200 or lower. 

-What should the f-stop be, and I’m assuming they’ll want to add as much light as allowed in the church?
                A f/2.0 lens set to f/4.8-f/5.6 will have a wider depth of field sufficient to capture subjects on a small stage area.
T stop is another factor, which is the adjusted amount of light that actually makes it through the lens to the camera sensor. Generally, more expensive lenses lose less light and have T stops nearly equal to their minimum aperture. 

-How do shutter and ISO factor in?
            When shooting any 4K camera with KMU-100, I recommend shooting at ISO 200, or at the minimum ISO because you want the least amount of noise in your images. I do not recommend shooting above ISO 400 on any camera. Shutter speed should be double the frame rate to have a good shot for low light and natural looking motion with subjects. Shooting at higher shutter speeds will result in a shot that is harder to light. 
I recommend shooting at 30fps and having a shutter speed of 1/60. 


Answers to Product FAQs


Datavideo support is here to help.