Image Stabilisation - why?

sgtdisturbed wrote:
Justin C wrote:
(Also posted to uk.rec.photo.misc, sorry to those who follow both
NGs, I intended to post it here but had the wrong NG selected when I
posted).

I keep reading about IS in modern cameras and lenses and people seem
to go on about it as if it's essential. It's not in any camera I
have and it was never in any camera I've ever had.

I've managed to get perfectly good and sharp shots over the years,
hand-held with 450mm lenses. The rule of thumb was that to avoid lens
movement ruining a shot you the shutter speed in fractions of a
second must be at least the length of lens used. So, if you're
shooting wide open in low light with a 50mm lens you can get away
with 1/60th sec. But if you're shooting on a sunny day, but in the
woods, with a 450mm you need 1/500 sec. You know there is a risk of
shake so you're careful, if you can use a tripod you do, if not then
a monopod, or a bean bag, or rest the lens on a branch, or lean
against a tree. With a little care you can get that speed down
without needing a tripod.

Just what is the big deal with IS? Have I missed the point? Weren't
most of the best photo's in the world shot without it?

I'm not looking to start a flame war and this is not a troll.

--
Justin C, by the sea.

Well, with IS you won't need a tripod as often as you would without
IS. Carrying ca camera, lenses, and batteries can be heavy enough,
throw in a 15-20 Lb tripod and the load can be a bit too much,
especially on a hike out to the woods to take nature shots where you
already have a 30-50 Lb ruck (if you wish to bivouac). Lightening the
load without leaving behind essentials can be tricky, so introducing
IS will allow you to leave behind the tripod.

Newer IS lenses (or VR) make long exposure shots come out nicely
without a tripod, and taking shots from within a moving vehicle are
possible without having to pull over to take pictures, and serious
zoom shots come out clearer without using the tripod.

Sounds IS itself is almost an essential part of photography, making
certain shots easier.

While it's true that IS helps...I still carry my tripod any time I'm
shooting seriously...unless I'm shooting wildlife where it isn't feasible.
Many circumstances need a tripod no matter what...like long exposures, or
landscapes with tiny apertures, etc. I'm a big IS fan, but it's no tripod
replacement...

--
Images (Plus Snaps & Grabs) by Mark² at:
www.pbase.com/markuson

Bill Hilton wrote:

With the Rebel you can set MLU, press the shutter once and the mirror
locks up, then wait before pressing the shutter a 2nd time, which fires
the shot and releases the mirror. You don't have to use the shutter
delay (which is only 2 sec with this model, so not practical).
-

acl wrote:

Why is it not practical?

You are locking up the mirror to avoid the shake caused by the mirror
slap, which affects the sharpness between a certain range of shutter
speeds (typically 1/8 - 1/30th sec).

A 2 second delay isn't long enough to let the vibrations damp down on
this body (I know this for certain because I can see it when looking at
Roger's test at high magnification). The cameras I use have 2 or 10
sec delays and 10 sec is always enough, but this Rebel XTi doesn't have
a 10 sec option.

It looked like 5-6 sec was always enough once I started using the
remote release (I didn't test this exhaustively), which agrees with
other tests I've seen.

My camera has a .4s delay (in addition to
MLU), and it is very practical indeed for lots of situations

I can't imagine what .4s delay buys you ... you're right in the middle
of the mirror slap.

It's not meaningless, there are lenses that protrude into the mirror
box and therefore cannot be used unless you can really lock the mirror
up between mounting and unmounting the lens.

The only 35 mm lenses I'm familiar with that require this are old
Minolta ultra-wide angles (I think 20 or 21 mm, something like that),
designed probably 45 years ago for the old Minolta manual focus mount
in the MC and MD lens era. But once you move into the world of
electronic shutters, which don't manually lock up, then lenses like
these are unuseable.

So who really cares?

Bill

John Bean wrote:

Yes, it can be a big deal when the mirror and lens try to
occupy the same space at the same time. Not all manuals call
it "mirror lockup" either - my Olympus E-1 refers to it as
"anti-shock" to indicate it's primary use.
-

acl wrote:

Indeed, on my D200 this function is called "M-Up", which I suppose is
shorthand for mirror up. There is a "mirror lock-up", which is a true
lock-up accessed through the menu and intended for cleaning the sensor
(so can't be used for taking photos).

But if this works like the Sensor Cleaning function in the Canon system
then you don't meet John Bean's definition for 'mirror lockup' either,
since (at least in the Canon) as soon as you turn the power off the
mirror returns to its usual position According to John it has to be
manually locked and unlocked, something that became archaic with
electronic shutters.

I see his point, but it's just meaningless semantics to me.

Bill

John McWilliams wrote:

Remote release. If one has steady hands, and presses the shutter
release gently with the camera on a sturdy tripod, where is vibration or
movement introduced such that remote release produces better results?

Hi John,

I bumped into this problem while taking 3 frames on a tripod at each
aperture of Roger's test pattern to find the 'best' resolution of a
lens before subsequently testing it hand-held. I could see variations
between the shots, indicating it wasn't entirely stable.

What I found was that just pressing hard enough on the shutter of the
XTi was enough to cause small vibrations at some shutter speeds. This
was on a very stable tripod setup (Gitzo 1325 carbon fiber with
Arca-Swiss B1 head). Whether this was because this camera needs a
robust push on the shutter button to fire or because of some problem
with the way I was doing it I cannot say.

Using the 2 second delay option didn't work well because it's not long
enough to totally dampen the mirror slap vibrations. There was no 10
sec option on this body, so I bought my wife a remote release for it
and set the MLU option and found that with a wait of 5-6 sec I got 100%
repeatable results, which was what I was looking for.

Bill

On 7 Jan 2007 13:55:30 -0800, "Bill Hilton"
wrote:


John Bean wrote:

Yes, it can be a big deal when the mirror and lens try to
occupy the same space at the same time. Not all manuals call
it "mirror lockup" either - my Olympus E-1 refers to it as
"anti-shock" to indicate it's primary use.
-

acl wrote:

Indeed, on my D200 this function is called "M-Up", which I suppose is
shorthand for mirror up. There is a "mirror lock-up", which is a true
lock-up accessed through the menu and intended for cleaning the sensor
(so can't be used for taking photos).

But if this works like the Sensor Cleaning function in the Canon system
then you don't meet John Bean's definition for 'mirror lockup' either,
since (at least in the Canon) as soon as you turn the power off the
mirror returns to its usual position According to John it has to be
manually locked and unlocked, something that became archaic with
electronic shutters.

I see his point, but it's just meaningless semantics to me.

It never really applied to Canon EOS, more important to
mounts like Nikon or Pentax that support legacy lenses. It's
not a matter of whether the shutter is mechanical or
electronic, simply whether ot not the mirror can be locked
in the up position - by whatever means - independently of
the shutter.

I realise there's much less need for this than there once
was, but that's no reason to hijack the definition of MLU
and apply it to something else. Call whatever most modern
cameras do as whatever you want, but it's not MLU ;-)

If you think this is "only semantics" you may be right, but
you're only right for the same reasons that some people
think cameras with EVFs are still SLRs, without considering
the meaning of the "R" in SLR. Same applies here - the "L"
in MLU has meaning... or should have.

Anyhow, 'nuff said, too much soap-boxing already.

--
John Bean

In article , John Bean
wrote:

On Sun, 07 Jan 2007 09:43:25 -0800, Ken Lucke
wrote:

In article , John Bean
wrote:

On 7 Jan 2007 06:47:29 -0800, "Bill Hilton"
wrote:

David Dyer-Bennet wrote:

Too bad no camera I've owned in 38 years of semi-serious photography
(i.e. I'm not counting my Pixie 127 or even my mother's old Bolsey 35, I
don't start the clock until I got my first SLR) has had MLU.

Do you have a dSLR? Even the cheapest entry level Canon digital Rebel
has MLU

No it does't. Mirror *lock up* means just that - the mirror
is locked in the up position until the lock is released.
Most modern cameras allow a delay to be inderted between
lifting the mirror and opening the shutter which sometimes
can be used as a substitute for MLU, but it isn't the same
thing.

YES, it does. In mirror lockup mode, my Canon 400D (as well as the
formaer 350D) raises the mirror with one shutter release (button,
timer, or cable) and it STAYS that way until I release the shutter a
second time. I believe that that fits the definition of Mirror Lockup,
don't you?

No I don't. You've decided to adopt the term "MLU" to mean
something else, and I agree you're not alone. But mirror
lift and mirror lock-up are two very different things in
some situations that may or may not be important to you -
but different they are, whatever you believe.

Don't speak with authority of that which you do not know.

Good grief, what a pompous thing to write.

Any more so than making a blanket declaration based upon some
personally-preferred definition which is contrary to general usage, and
then defending it based upon semantics?

Explain in minute detail how your defined style of MLU is, on today's
modern [D]SRL, going to be of any benefit over the generallty
understood term/functionality of separately (in an additional step)
moving the mirror out of the way prior to the shutter actualtion?

--
You need only reflect that one of the best ways to get yourself a
reputation as a dangerous citizen these days is to go about repeating
the very phrases which our founding fathers used in the struggle for
independence.
-- Charles A. Beard

Bill Hilton wrote:
Bill Hilton wrote:

With the Rebel you can set MLU, press the shutter once and the mirror
locks up, then wait before pressing the shutter a 2nd time, which fires
the shot and releases the mirror. You don't have to use the shutter
delay (which is only 2 sec with this model, so not practical).
-

acl wrote:

Why is it not practical?

You are locking up the mirror to avoid the shake caused by the mirror
slap, which affects the sharpness between a certain range of shutter
speeds (typically 1/8 - 1/30th sec).

A 2 second delay isn't long enough to let the vibrations damp down on
this body (I know this for certain because I can see it when looking at
Roger's test at high magnification). The cameras I use have 2 or 10
sec delays and 10 sec is always enough, but this Rebel XTi doesn't have
a 10 sec option.

Well, resting my camera against a wall or something similar, I find it
useful (to avoid pressing the shutter release with my finger and shake
the camera). Since I actually carry my SLR all the time, not just when
I am going somewhere specifically to shoot something, I often have to
do this (I almost always take photos on my way to and from work, ie
often at night or early morning). The results may or may not be the
best possible, but they're better than handholding (or nothing).

Regarding mirror slap: I do not use anything longer than 90mm at the
moment, and using the .4s delay does require considerably more care
than using MLU and a remote release, but I can assure you it can give
identical results, at least as far as I can see when looking at
pixel-level on my screen. It may take 2-3 tries though, and holding the
tripod to damp the vibrations, especially at high magnifications
(macro). Anyway, clumsy, but useful if you forget the remote release
home . It's ok if you don't believe this, let's not get into an
argument. Maybe I am blind or incompetent, but these are my findings.


It looked like 5-6 sec was always enough once I started using the
remote release (I didn't test this exhaustively), which agrees with
other tests I've seen.

My camera has a .4s delay (in addition to
MLU), and it is very practical indeed for lots of situations

I can't imagine what .4s delay buys you ... you're right in the middle
of the mirror slap.


Well, as I said, I tried this and it sort of works. I'm sure it depends
on the tripod, lens (focal length, physical properties etc), how you
trigger (shutter release button or remote release), and many other
things. But my point was that some people do not always have a good
tripod with them, or a remote release, or any good means of support. If
you have a tripod and a remote release cable, then obviously it would
be stupid to use this delayed release thing.

It's not meaningless, there are lenses that protrude into the mirror
box and therefore cannot be used unless you can really lock the mirror
up between mounting and unmounting the lens.

The only 35 mm lenses I'm familiar with that require this are old
Minolta ultra-wide angles (I think 20 or 21 mm, something like that),
designed probably 45 years ago for the old Minolta manual focus mount
in the MC and MD lens era. But once you move into the world of
electronic shutters, which don't manually lock up, then lenses like
these are unuseable.

So who really cares?

I know for sure there's a Byelorussian (or whatever the correct
spelling is nowadays) 8mm fisheye that needs this and fits Nikons.
Costs 1/5 (or maybe even less) the price of the equivalent Nikkor
(which is also discontinued for some years, if I am not mistaken). I am
sure there are others, but cannot really bothered to search now as I
don't think I am actually disagreeing on this with you. Anyway, if you
don't care about these, fine (I don't either, its image quality is far
too bad). I was just making a point. Which it looks like it will not be
conceded, and I think we are all now arguing just to argue.

On Sun, 07 Jan 2007 15:11:23 -0800, Ken Lucke
wrote:

Explain in minute detail how your defined style of MLU is

[snip]

Ken, go play your childish games with someone else, you're
history to me.


--
John Bean

In article , John Bean
wrote:

On 7 Jan 2007 13:55:30 -0800, "Bill Hilton"
wrote:


John Bean wrote:

Yes, it can be a big deal when the mirror and lens try to
occupy the same space at the same time. Not all manuals call
it "mirror lockup" either - my Olympus E-1 refers to it as
"anti-shock" to indicate it's primary use.
-

acl wrote:

Indeed, on my D200 this function is called "M-Up", which I suppose is
shorthand for mirror up. There is a "mirror lock-up", which is a true
lock-up accessed through the menu and intended for cleaning the sensor
(so can't be used for taking photos).

But if this works like the Sensor Cleaning function in the Canon system
then you don't meet John Bean's definition for 'mirror lockup' either,
since (at least in the Canon) as soon as you turn the power off the
mirror returns to its usual position According to John it has to be
manually locked and unlocked, something that became archaic with
electronic shutters.

I see his point, but it's just meaningless semantics to me.

It never really applied to Canon EOS, more important to
mounts like Nikon or Pentax that support legacy lenses. It's
not a matter of whether the shutter is mechanical or
electronic, simply whether ot not the mirror can be locked
in the up position - by whatever means - independently of
the shutter.

I realise there's much less need for this than there once
was, but that's no reason to hijack the definition of MLU
and apply it to something else. Call whatever most modern
cameras do as whatever you want, but it's not MLU ;-)

If you think this is "only semantics" you may be right, but
you're only right for the same reasons that some people
think cameras with EVFs are still SLRs, without considering
the meaning of the "R" in SLR. Same applies here - the "L"
in MLU has meaning... or should have.

Well, using that argument, none of us using digital are actually
practising true photography anyway. I have a 1910 dictionary here
(14" thick - it's a monster) in my "old world" room that defines
photography as:

"The art of producing images by way of an application of the
chemical changes produced in certain substances, as silver
chloride, bromide, or iodide, by the action of light, or more"
generally of radiant energy."

Because a digital camera produces its images due to _electrical_
changes [or production] in certain substances when exposed to light, we
no longer fit that definition, nor the following one from another
early-century dictionary on hand:

"The process of producing an image by exposing to light an
emulsion of light sensitive chemicals on a glass, metal, or
celluloid film base."

I'm sure that even earlier dictionaries would tie it down even more
closely to only using glass plates and similar equipment.

My point is: equipmment changes, words change, and both change to
reflect current usage. To tie a term like "mirror lock up" to
equipment which is no longer prevalent and to maintain that using it in
a current context for an equivalent feature on modern equipment is
wrong, is like saying that we no longer practice photography because
it's not what the original definitions of it specified.


Anyhow, 'nuff said, too much soap-boxing already.

Well, that much is true, anyway.

--
You need only reflect that one of the best ways to get yourself a
reputation as a dangerous citizen these days is to go about repeating
the very phrases which our founding fathers used in the struggle for
independence.
-- Charles A. Beard

In article , John Bean
wrote:

On Sun, 07 Jan 2007 15:11:23 -0800, Ken Lucke
wrote:

Explain in minute detail how your defined style of MLU is

[snip]

Ken, go play your childish games with someone else, you're
history to me.

Sounds like the sound of retreat to me.

--
You need only reflect that one of the best ways to get yourself a
reputation as a dangerous citizen these days is to go about repeating
the very phrases which our founding fathers used in the struggle for
independence.
-- Charles A. Beard