He just says, "DO NOT USE" in regard to the the pre-AI lenses on
digital cameras. Not helpful. It's a little more nuanced than that.

Yes, I've found that the "electronic range finder" feature works
equally well with non-AI lenses as it does with AF lenses in manual
mode. One problem that I have, in both cases, is that if objects at
widely differing distances are close together in the center of the
picture, the electronic indicator will signal "in focus" if you
actually focus on *any* of the objects. That's why I find a
split-image rangefinder a lot easier to use.

Well, one must obviously be very careful when trying a particular
combination for the first time. I found, with the non-AI lenses I
tried on my D70 camera, that the amount of deflection was absolutely
minimal, and well within the designed side-to-side range of motion of
the switch tab. If the aperture ring on a particular lens is a
slightly larger diameter, you could have a problem. The answer is
never to force anything, and always look carefully at what you're
doing.

Nikon makes such blanket statements to protect themselves legally. If
something goes wrong, they're not responsible. But sometimes you can
get more use out of a product by "pushing the envelope." Examples are
making "off-label" use of medications, or overclocking computer
processors.

You can't meter anyway with a non-CPU lens. You have to use the camera
in full manual mode when using a non-AI lens. The minimum-aperture
switch is inoperative in such a scenario.

Yes, it's the minimum-aperture switch tab, which is at the 8 o'clock
position (as you're looking at the front of the camera) just outside
the lens mount ring.

On the D40, this tab retracts inside the camera body, On the other
low-end Nikon digital cameras, there *may* be enough "wiggle room" in
the tab to clear the lens aperture ring. Knowing what to look at, you
may be able to coax the lens into position. Don't force anything.

That's the well-known problem with the automatic-indexing ridge and
tab. (The FM has the flip-up tab also, while the FM2 doesn't.) The
low-end Nikon digitals don't have this problem, since they don't use
mechanical indexing.

In my opinion, the proper way to convert a pre-AI lens is to use a
Nikon factory replacement aperture ring. (Some are still available.)
Otherwise, the conversion involves milling or grinding the original
ring, and there are not that many craftsmen who can do a really good
job at it. I've seen lots of cases where someone just crudely used a
Dremel tool to grind away at the ring. Maybe it works, but it reduces
the lens' resale value to zero.

Faced with chancing this kind of conversion, I would just try to buy
an equivalent AI lens.

"Matt Clara" <hey.wood.y@buzz.off> wrote in message >>

Anyway, I've put a non-AI lens on my D70, and taken pictures. (In

You should be able to do this with any digital camera without having to take
the picture....Just look in the LCD display "viewfinder" and adjust the
"exposure" until the picture looks right, and then take the picture....I
wonder why they don't give you this ability?

You're right -- I wouldn't do this on a regular basis, since I have
plenty of AI lenses. I just wanted to see if it could be done. But who
knows? Somebody out there may need to do this for one reason or
another.

ith

could you tell me more about the conversioin? or a link..

i just got myself a used-refurbished D100 and i have 4 nikon non-af
lenses

g

The flip-up tab on the FM, as well as on the F2A, F2AS, F3, F4, etc.,
is for engaging the automatic-indexing ring on the lens. The problem
on the digital cameras revolves around an entirely different tab, that
for the minimum-aperture switch (it's on the opposite side of the lens
mount). Actually, the low-end digital cameras (up to the D80) don't
*have* the tab you're talking about. They have an entirely different
system for reading the lens aperture. Conversely, the FM doesn't have
a minimum-aperture switch, since the switch is used for
automatic-exposure modes.

The D70 like a lot of the cheaper DSLRs use a mirror prism with out
much magnification in the finder, makes for  tunnel effect viewing. The
D200 and D80 both use prisms and magnification like film SLRs. Since
the size of the sensor is 1/2 that of 35mm film the view finders on
these cameras seem small too. though they are as bright as a film SLR.
DSLRs are also built with autofocus in mind so the viewing screens
aren't as good as with film SLRs. Though I find my D200 reasonably easy
to focus with Ai lenses.

Tom

That isn't as practical as simply shooting off an exposure and
then looking at a histogram to get a rough idea of the exposure,
or at a "blink-on-over-exposure" LCD display to get a more
precise measure.

It takes anywhere from 1 to 5 quick exposures, which cost
nothing with digital, and allows *very* precise exposure
settings.

Modern digital cameras have an Auto Focus indicator, but don't
have manual focusing aides such as a split prism and microprism
collar that was typical of a manual focus film camera.

Those aides are not necessary, but they certainly are nice!
Because the split prism is located dead center in the viewfinder
it is easy to maintain framing/composition and focus at the same
time.  Your eye doesn't have to move.  With an AF camera you can
look at the AF indicator while focusing, but it is typically
down in the right hand corner of the view finder, which makes it
more difficult to see while trying to hand hold.

You can get replacement focusing screens for many camera models.

  http://www.katzeyeoptics.com

Everyone who has used them seems to say good things.  (I have
one on a Nikon D2x, and find it well worth the price.)

All told, non-AI lenses are a bit of a pain.  And sometimes AI
lenses are too, compared to AF lenses.  For some things they
are well worth keeping if you already own them, and for a few
things they are a better buy than a new AF lense (macro work,
for example).  But for sports, taking pictures of children, or
anything that moves...  Auto Focus is *fabulous*.

If you are a bit of a techie and like playing with mechanical
devices, consider MF lenses.  If not, stick with AF lenses and
don't even bother thinking about older lenses.

The D70 has DOF preview, but it only works with CPU lenses. Thus, it
can't be used for stop-down metering.

First, it has a relatively dim viewfinder (this problem has apparently
been corrected in the D200). But more important is the lack of a
split-image rangefinder. This can be addressed by getting a
replacement Katz Eye focusing screen for $105.

Is the meter active?  I think it may notice such a lens is mounted and
completely disable the display.

Different focusing screen -- optimized for *seeing*, not for focusing
(since the AF system is expected to be doing the focusing).  You can use
the focus confirmation light from the AF system, which helps some.