Godfrey DiGiorgi wrote:
On Apr 22, 2006, at 10:00 AM, Denny B wrote:
I am anticipating purchasing a Pentax Digital DS2 body.
Can I use my manual Pentax lenses I have collected over
the last 35 years on the DS2 body, Some lenses
are A-lenses, some are just SMC non A-lenses.
Can I focus these lens manually and observe through the viewfinder
that the lens is focused but even though I manually focus
still get electronic signal (light or beep ) that the lens is
focused?
Yes. It's generally best to ignore the focus confirmation when
working with fast lenses, however.
Can I use all light metering functions ( matrix, center weighted,
spot ) with the A-lenses and some metering functions with the non A-
lenses.
A lenses obtain all metering functions, both ambient and flash.
Pre-A lenses get spot and centerweighted, work fully in Manual or B
exposure mode. (They also work in Av but only wide open, and all
other exposure modes default to Av.) Instructions for using pre-A
lenses:
---
M/K-Bayonet lenses without an A position on the aperture ring can
only be used in Manual exposure mode, effectively. They'll also work
in Av mode but only at wide-open aperture. To use them:
0: set the custom function for Using Aperture Ring to "permitted". Do
this once and leave it that way.
1: Set camera to Manual exposure
2: Frame and focus on subject
3: Set desired aperture on the lens
4: half press shutter release to activate the meter.
5: frame subject, press AE-Lock button to take a meter reading
(lens will stop down briefly and the correct shutter speed will be
set)
You're ready to take a picture.
The built-in flash with pre-A lenses operates unmetered at full
output; Pentax-dedicated external flashes will support TTL metering
on the DS/DS2. There's a table in the instruction manual with guide
numbers to allow you to set the aperture per distance.
Godfrey
I'll just note that M42 lenses get full function in Av mode, as long as
you don't have them set on AUto (which you shouldn't when using an adaptor).
-Adam
