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Message: <blockquote data-quote="typo" data-source="post: 3560085" data-attributes="member: 83808">LGM,The average low light pupil maximum for 60 year olds might be between 5mm and 5.2mm in the various studies I've seen but there is individual variation as others have been keen to point out. <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" />  Most individuals will fall in the 4mm to 6.6mm range but there will be outliers. Knowing your own maxim would be helpful. If your optician is obliging he can put drops in your eyes and do a measurement for you, but don't drive for the rest of the day. HenyLink on the forum has described how to use a defocussed point light source (artificial star). Some, with I presume pale irises, just stand in front of a mirror with a ruler placed under the eye. Probably the easiest is to use a preferrably prefocused, mounted camera and just take a photo of yourself and the ruler after sitting in the dark for 10 minutes. Make sure you don't look at the screen in the mean time. Or get someone else to take the shot for you.:t:The Duovid is not a binocular I know well but I got the impression there wasn't a lot of blue in the transmission spectrum. David</blockquote>