URSA Mini Pro Feature request

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Marc Bartholomew

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URSA Mini Pro Feature request

PostMon May 15, 2017 2:35 pm

I would like to request a change to the White Balance hard switch functionality. I'm currently using the UMP for a weekly lifestyle TV show, so sort of the worst case run and gun, following people around, etc. The white balance switch to ramp up and down is currently not helpful. If I'm shouldered up I can't use the hard switch as it only ramps the WB up and down, not the Tint, so If I start with a tint compensated preset by the time I ramp to the other end of the spectrum the tint is way wrong. So I have to use the menu wheel and back button to go through the on screen controls through the viewfinder, which is quite a slow process.

What would be ideal is the ability to make that hard switch go between 4-5 custom WB presets. As I'm following the talent from shade to sun or indoors to outdoors I could just bump that switch and go the next preset.
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Denny Smith

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Re: URSA Mini Pro Feature request

PostWed May 17, 2017 2:49 am

Presets only work for fixed lighting situations, outdoor shade or sum, will change co,or temp depending on time of day. Just set a white/grey card out and do a quick AWB, done. Leave the tint set to offset any co,or casts from the sensor/lens combo, not to WB the camera.
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Denny Smith
SHA Productions
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Marc Bartholomew

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Re: URSA Mini Pro Feature request

PostWed May 17, 2017 11:34 am

When I have time or help I do the card and AWB, but that isn't always the case in my situation. I can't physically hold the card out at the focal plane of my subject (my arms are long but not that long). Presets let me get in at least the right ballpark, and the remainder can be quickly tweaked in post.

My understanding of tint is that it changes as you change your WB, as WB is a curved response in the spectrum, thus the current built-in presets which have compensation tints applied already. As you go from warm to cool there is a shift in the green and magenta. This is different from tints from lens and filter and light sources - that can be dialed out as well. Maybe I'm wrong though but I thought I read that somewhere...
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rick.lang

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URSA Mini Pro Feature request

PostWed May 17, 2017 12:25 pm

Marc, you are correct, but the tint in the presets appear to be more applicable to a perfect sensor response to perfect light as we've seen the chart that I believe CaptainHook provided illustrating how tint varies with temperature. The presets are inaccurate though in an imperfect sensor. Doing the AWB will dial in the the correct tint for your scene lighting and your sensor's response. Sometimes the AWB tint is the same or very close to a preset, but other times, it's quite different in my experience.

Your grey card or white paper can be set in the scene as Denny mentioned. But it doesn't need to be in focus, so you might still get good results if you hold it at arm's length when you have no other option or assistant. Anyone nearby will hold it for you when they see you shooting with a Pro camera (and not a hacked GH2).


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Rick Lang
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Denny Smith

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Re: URSA Mini Pro Feature request

PostWed May 17, 2017 6:36 pm

Yes, Rick is right, and having the card out of foucs sometimes works better. The card just needs the sam light as the subject hitting it, so outside and in shade, a small 5x8 card held out in front of the lens works fine, and still more accurate than a preset, which has got me into more trouble than not in the past wi cameras that had them. A preset works in situations that do not change, like a fixed indoor lighting setup, AWB and save to a preset.

Outside, it is better to do a AWB, unless you aremshooting in a fairly short time frame, as in a wedding, where you can get a shade and sun AWB, and save them to a preset, once the wedding party moves outside. But a exterior AWB is only good for an hour or so, or if you have varying amounts of clouds passing by, changing the light quality..
Denny Smith
SHA Productions
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Chris Clifton

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Re: URSA Mini Pro Feature request

PostThu May 18, 2017 6:40 pm

Gray card, yes, white card, no. Huge difference in the two with this camera--it absolutely loves gray card balance for whatever reason (most cameras do) and skin tones are dead on with it. Keep a little one with the camera, it's worth the extra 5 seconds of time.
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paulgolden

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Re: URSA Mini Pro Feature request

PostFri May 19, 2017 7:38 pm

I guess I'm a little unclear on the difference between the front AWB button and the AWB accessed from the color temp menu on screen. Should the results be identical? In testing between the two, it seems like it's not precisely the same, but apart from lazy testing, I'm not sure how they're different. Can anyone elucidate?

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