In article
>I was looking into extension tubes for my Pentax P30T which new cost $109
>from B&H (for macro photography). My girlfriend went to a Ritz camera
>dealer and he told her a cheaper answer was some sort of magnifier screwed
>on the end of the lens. I figured that this would be another optical
>element and may not produce the same quality photographs as extension
>tubes. Anybody have any opinions on this?
You are probably right, unless the close-up lens is an "achromat"
(2-element close-up lens, made by several camera mfgrs. and Sigma
[for their 90mm macro]), in which case, it could go either way,
depending on the lens optical design (some are the pits on tubes,
some good - the symmetrical optical designs tend to be the good
ones, but I have seen exceptions both ways). Whichever way you go,
use smaller apertures for best results (about f11 is usually good).
A TTL flash placed up near the front of the lens and aimed down at
the subject greatly simplifies close-up shooting.
Hope This Helps