Discussion
The colorimetric evaluation yielded the type of results that were expected. It is apparent that the Regalrez varnish did help level the rough surface of the painting, which reduced the scattering of the light incident on the target.
The SFR analysis did not yield the expected results. The two varnishes for this experiment were chosen because of their difference in molecular weight. It was expected that the PVA, whose molecular weight is much higher than the Regalrez varnish, would show a significantly lower CMT Acutance result. Instead, they only differed by .3. Currently, it is thought that the varnishes were applied too thickly on the targets, thus making both varnishes to appear to behave in the same manner. It is necessary to devise a way to consistently apply the varnish in a much thinner layer. Another unexpected result that was noticed was that the varnished target had a worse SFR than the unvarnished target. This conflicts with the idea that the varnish decreases the scattering of light, which would ultimately increase resolution.
The methods used for the colorimetric analysis seemed to be quite acceptable. They were consistent with qualitative observations. Because the method for spatial frequency analysis is a rather new idea, there are many aspects that could be altered to try and achieve better results. First, there was the before mentioned varnish thickness and concentration of varnishes in solution. These could both be reduced to produce a much thinner layer of varnish that may lead to better results. Also, the viewing distance of the camera could be made closer to the target. Because the variations that are being looked for are very subtle, they might be somewhat pronounced if the image area of the slant edge target was enlarged.