[NHCOLL-L:5485] Colour of thin section images

[Christian Baars]

Hi,

we are having slight issues with the colours of images captured using a digital camera from a petrological microscope. The colours on images of petrological thin sections are never quite like those seen through the eye pieces. This can be adjusted using Photoshop but if taking a large series of images this can be quite laborous; it would be better to capture the correct colours in the first place.

Capturing images from stereomicroscopes we use a colour chart to calibrate the camera and to do a white balance prior to taking photos. With a petrological microscope this is obviously not possible, but I am wondering whether the principle may be.

Does anyone use a thin section with a standard material that appears to be white under the petrological microscope (plain polarized light)? Using simply a clear glass slide is not an option as we would just be calibrating the camera against the colour of the light from the lamp which is not necessarily white. Instead, we are looking for a material that we can use to make up a standard thin section for setting up a white balance.

Any ideas would be gratefully appreciated.

Kind regards
Christian





Dr Christian Baars
Department of Geology
National Museum Wales
Cathays Park
Cardiff CF10 3NP
UK
Telephone: 0044 (0)29 2057 3352







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