Archived from groups: rec.photo.digital (
More info?)
On Tue, 12 Jul 2005 23:04:02 GMT, TycoonUK
<tycoonuk@hotmailnospam.com> wrote:
>Yes I mean extension tubes.
>I got some from a friend of a friend and just would like some idea how
>to use them?
>I know how to put them together, but it is using them with the D70 I
>could do with help.
That depends on whether the tubes you have possess the electrical
transmissions for diaphragm and autofocus, and/or the screwdriver
transmission for mechanical autofocus (the D70 has all these).
In macro, autofocus is practically useless, so you should use manual
focus anyway. If the tubes have no electric contacts to read the
diaphragm opening, only manual exposure is possible with a D70. You
can use an external meter and compensate for the length of the tubes
(two stops for 1:1 ratio, I believe), but it is easier to make a
couple of test shots before taking the "real" one and check the
exposure with the histogram on the LCD screen of the D70.
If you use flash (in manual mode), exposure will always be essentially
the same for a given magnification ratio, diaphragm setting and flash
power, so you could compile a table of these values and use it as an
initial setting (and then compensate for very light or dark subjects).