M.Chapman Posted February 5, 2020 Share Posted February 5, 2020 On 03/02/2020 at 09:10, Harry Harrison said: I think the changes you've made have been beneficial, and I also agree that the artefacts in the sky are the dye-clumping effects you get with film. I did some further investigation and have found the cause of slight mottling in the sky. The upside-down B&Q LED downlighter I'm using as a "lighbox" has a textured diffuser. I was supporting the slide several mm above it assuming the texture would be out of focus. Turns out that I was incorrect, at the edges of the frame the texture is very slightly visible as "mottling". I'm not sure if that is due to field curvature of my lens, or the increased "speckle" when looking at the diffuser from and angle. Anyway, the solution is simple, I just increased the spacing between the slide to 15mm and the slight mottling has now gone. Mark Link to comment Share on other sites More sharing options...
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