LCC Profiles for Cambo Ultima and P25+

[Junk_Bond]

Hello Everyone,

When working with the Cambo Ultima and P25+ back I have noticed some images have a color cast, especially when using movements. Would the following link be the correct procedure for creating an LCC for each capture? Thanks

https://dtekuk.wordpress.com/lcc-calibrating-fixed-lenses-in-capture-one-6/

[Christoph B.]

To ensure the correct exposure, you might have to open a few f-stops in very light conditions or put more light directly on the plate in dark conditions or setups.

I would not open the aperture, that would change the behaviour of the lens, Instead use a higher ISO or longer exposure if possible.

In short:

1. Take a photo with a calibration card (or just a thin piece of white plastic - just be sure it's even) right in front of the lens. Try not to leave any gap between the lens and the plate as light coming from the side could (in theory).

2. Take the photo without changing anything about the lens (same aperture, focus, movements...).

3. In CaptureOne you can create a LCC profile for the calibration shot. You have the option to include dust settings but I had some problems with that, it used to crash while doing that and it also takes much longer.

4. Copy the LCC setting from the calibration shot and apply it to all the photos you took with the same lens settings and movements.

However keep in mind that lens flares can not be reduced or removed by this method!

[tho_mas]

as said above...: do not alter the lens settings but increase shutter speed by ~2 stops.
In addition: the histogram of the LCC shot of course must show no clipping in the highlights or shadows at all - in my experience the LCC works best when the LCC is exposed to be in the middle or in the right third of the histogram ...
When shooting "stock" LCCs (used as "presets" in C1) you should shoot them with the lens set to infinity (and of course a separat LCC for each aperture of a given lens).