5 Jul
2011
5 Jul
'11
1:11 p.m.
> Can you
use 'traditional' closeup methods (extension tubes, bellows, etc)
> with digital SLR cameras? If so, that's what I would be looking at using.
To answer Tony's question, in general, yes of course you can use rings,
bellows, and all the other things with digital SLRs. I suspect he knew
that, maybe he was asking if Dave has access to those things.
Dave, can you get hold of a set of extension rings? or a bellows unit?
That'll get you better magnification. And use a shorter focal length
with tubes or bellows; that increases the magnification. A good trick
if you can do it is to turn the lens round. Firstly that's because
How will the automatic coupling work if you turn the lens round? Most
DSLR lenses that I've seen lack manual control of aperture, etc so you
might have problems.
I always thought Praktica got it right on the VLC series. Open-aperture
metering was coupled by 3 contacts on the lens mount, stop-down was the
traditional M42 pin. There was a pair of rings, one screwed into the
camera mout, the other on the back of the lens. The wrre linked by a
plug-in cable to carry the aperture data, an a double cable release
stopped the lens down befroe tripping the shutter. Point being you could
turn the lens round (coupling ring now on the subject side of the lens)
without any problems.
camera lenses are optimised for a short distance
between lens and
film/sensor and a longer distance between lens and subject; here the
situation is reversed so the lens will usually work better back to
If you can use a totally manual lens (no automatic diaphragm at all), a
good quality enlarger lense (EL-Nikkor, for example) is good for this.
front. Secondly, you can often get the lens closer to
the subject when
it's reversed, especially with a retrofocus lens (ie a "wide angle"
lens). Don't try to focus by turning the focussing ring (or moving the
In a lot of 'tradiitoanl' cases, the focusing mount does absolutely
nothing if the lens is reversed. It moves the entire optical unit
(imcluding the front filter thread) relative to the cmaera mounting
flange, so when the lens is reversed it doesn't actually move anything
useful.
Of course if you happen to have a Rollei SL66, you cna reves the standard
lens on the built-in bellows with no extra bits at all. But I've never
seen a ditital back for one of those.
bellows in and out if you have one); you've
possibly already discovered
it's easier to set the magnification and then move the whole unit back
and forth to get the focus. Ideally, stop the lens down about halfway
or just a bit more; that's when most lenses are at their sharpest.
This depends on the subject. For flat subjects like fiche, I would agree
with you (most lenses have a peak resolution around f/5.6 or f/8). For
3-dimension subjects, like bits of classic computer, you may need to stop
down further to get enough depth of field.
-tony