[chris lewis]

I receved an E. mail from Mike Smith at Bintel [via Mike Salway]. It does appear that the Meades do have 63 mm clear aperture.


Somebody pointed out to me a review of Meade binoculars on IceInSpace and noted the following:
'One negative issue is they do not appear to be the full 63mm's aperture as advertised. There is a ‘cell holder / baffle’ more or less immediately behind the main lens. Measuring the effective aperture comes out to be 'approx'. 58 - 60mms. It is curious as to why this cell ‘holder / baffle’ is so close - as any loss of light is a major negative'.


Many objective lenses (binos, eyepieces, finderscopes etc) show this strange effect. It looks like a shiny black cut-out baffle attached to the rear of the objective. It's not there! It doesn't exist.
When the objective housing is unscrewed and examined there is no baffle behind it. I have demonstrated this strange fact to one well-known local 'expert' and he was dumfounded when he saw the reality. (This effect is often seen with 8 x 50 finderscopes). It isn't just an effect with Meade binoculars. Have a look at others, including finderscopes and you'll see it there too.
I don't know what causes it, but it is some sort of optical illusion. Maybe somebody somewhere can explain it, but I can't.


Regards Mike Smith

Thanks to Mike Smith - It is important to 'get it right' - so my review is amended to acknowledge that the Meade is correctly advertised as a 9x69mm Binocular