Wow..........try reproducing that from memory on a blackboard !
Revet
Loc: Fairview Park, Ohio
Here is the formula. I think we blew through that in 1st grade!!
Of course that formula makes perfect sense, although I was a bit confused by "the minus 1" in the third line at the last set of parentheses.... I'll have to re-read it to be sure!
Now, how soon will they make it in plastic?
Bob
The formula may greatly solve the problem on paper, but its conversion to drive a manufacturing machine is altogether another problem. How do the lens machines actually work. In the first instance - glass is a mixture of individual silicon oxides some with other elements (the chemical kind) substituting for the O or Si. Is the mixture a solid solution or a mixture (the two are chemically different) and is the latter homogeneous. Consider the grinding & polishing machine settings - remember if a dial has settings of x dimension the standard error is 1/2 x. Pop that error into that equation and many hours later get the error in the result!
at present must be theoretical, possibly applicable to moulded plastic when we learn to generate the moulds ?
producing and grinding glass elements for specialty lens take way more time . The holy grail of lenses The NIKON 13mm f5.6 reported to be the best and widest lens ever made Was said in reports that front element alone took over a year to make ,anneal,grind and polish . There were only I believe 350 or more made on special order after payment at the time...
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