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Message: <blockquote data-quote="edz" data-source="post: 1379336" data-attributes="member: 44073">These excerpts from another RC article might stir some thought on two points; 1)using a camera to detect color cast - the main point here being that the camera detector is much different than the eye as a detector, and 2) color correction  (degree and bias of chromatic aberration) of a lens has some influence on the color cast of the output.  Considering the very fast optics of binoculars, CA bias may influence color cast to some level.Color Correction in Refractors by Roland ChristenIn lenses, the key (to color correction) is the color of the in-focus disc. The whiter it appears at focus, the better is the correction. In a lens with lesser color correction, the in-focus disc will appear more and more yellowish To clarify the situation on color correction a bit more ... I will attempt to explain where achros, EDs, fluorites etc fit into the scheme of things by comparing the ability of each design to produce a reasonably focused image spot diameter over its wavelength range. Fast 6"F8 Cde achromat:  550 - 650 nm Fast 6"F9 ED doublet: 450 - 650 nm Fast 6" fluorite doublet: 420 - 1000 nm Fast 6" fluorite triplet: 360 - 1000nm...why would you need correction well into the blue-violet past 480nm? With black and white emulsions, this was necessary because they have considerable sensitivity down to 380nm. Today's new blue sensitive CCD cameras also need good correction in the violet. Also, CCD cameras pick up lots of IR light below 650nm, so correction to 1000nm is a distinct advantage. For pure visual use, it would be quite sufficient if the useable range extended only from 440 to 650 nm.See post above for link to Astro Physics articles.</blockquote>

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