01-19-2020, 07:40 PM
(01-19-2020, 05:59 PM)Rover Wrote: [ -> ]Can distortion be variable from copy to copy? O_o I mean, from one healthy copy to another, not counting damaged or badly decentered lenses.
No.
(01-19-2020, 05:59 PM)Rover Wrote: [ -> ]Can distortion be variable from copy to copy? O_o I mean, from one healthy copy to another, not counting damaged or badly decentered lenses.
(01-19-2020, 05:57 PM)Brightcolours Wrote: [ -> ]Distortion will NOT vary from copy to copy. ...
(01-19-2020, 07:41 PM)JJ_SO Wrote: [ -> ]I can't help it that you find it hard to believe.(01-19-2020, 05:57 PM)Brightcolours Wrote: [ -> ]Distortion will NOT vary from copy to copy. ...
That's a statement I find hard to believe. Everything varies, especially centering and resolution. if these properties are variable in each specimen, I see no reason why distortion is not affected.
Also, using the same software doesn't mean the setup for each lens test (site) is identical. The software programmers don't deliver the full hardware equipment, do they? Maybe I'm wrong but a lot of these testers don't appear to have a solid professional background as optical engineer.
(01-20-2020, 06:30 AM)Klaus Wrote: [ -> ]Distortions will not vary between samples in any substantial way.
Of course, there'll be slight variations - lenses aren't digital after all - but there'll be no qualitative difference.
(01-20-2020, 08:52 AM)thxbb12 Wrote: [ -> ]It seems likely to be variations in the way things are setup'ed.
(01-20-2020, 08:23 AM)JJ_SO Wrote: [ -> ](01-20-2020, 06:30 AM)Klaus Wrote: [ -> ]Distortions will not vary between samples in any substantial way.
Of course, there'll be slight variations - lenses aren't digital after all - but there'll be no qualitative difference.
Can you quantify the "non-substantial" way? To me the diff between -1.28%, -1.35% makes 0.07%. I would not call that "substantial". That was my reason to ask for sample variation. Be it that, or variation in measuring method, I still don't believe that distortion is absolutely excluded from any variation. The differences might be very small and neglible, but there's absolutely no reason why this property should not be affected. There are differences in resolution big enough to appear on charts...