7th November 2009, 06:26 PM
Re: How to measure magnification?
Sorry, but I couldn't help it.
Being called a 'scholar' nowadays is regarded as 'name-calling' and being labeled derogatorily?
Anyways, without going into the headache calculations ... you were not short-changed.
A '+' (or even '-') prefix is only a measure of a lens' diopter, and NOT an indication of a fixed magnification capability, which as you found out, is dependent on various factors.
My suggestion is to only use the +1, +2 and so on designation as an indication of what filter you need, or for a reference.
If you need super-precise decimal point magnification calculations, that's different.