Mirror slap?

On Apr 1, 11:13 am, "William4" <w....RemoveThis@news.com> wrote:
> Assuming film - dig slrs are the same in this respect (but query relates to
> dslr);
>
> When does mirror slap, or whatever it is called today, show itself.
> Faster or slower shutter speeds or does it really 'all depend',
> I.a. is it a pretty quick event that I might see at very high speeds and has
> little impact (relatively) at low speeds,
> or a slow one that might be a problem with longer exposures.


Mirror slap or mirror jump or mirror bounce is caused by the mirror
quickly moving upwards to get out of the way when you are taking a
picture. Under most circumstances it is noting to worry about.

However, it is a concern under two primary circumstances. First, is
for a large telephoto lens because all vibrations are magnified.
Second is long exposures, esp. with high ISO settings, because the
bounce will show and esp. cause bluriness of light sources.

Mirror lockup works better than using the timer because there is still
bounce with the time. If you are experiencing a problem with it, a
good tripod is also needed. You can also try weighing down your
tripod to add stability.
 >> Stay informed about: Mirror slap? 

Neil Harrington wrote:
> "William4" <w4.TakeThisOut@news.com> wrote in message
> news:Q_PPh.20669$2F5.2684@newsfe5-win.ntli.net...
>
>>Assuming film - dig slrs are the same in this respect (but query relates
>>to dslr);
>>
>>When does mirror slap, or whatever it is called today, show itself.
>>Faster or slower shutter speeds or does it really 'all depend',
>>I.a. is it a pretty quick event that I might see at very high speeds and
>>has little impact (relatively) at low speeds,
>>or a slow one that might be a problem with longer exposures.
>
>
> With modern SLRs I don't think mirror slap is a factor to be concerned about
> at any shutter speed.
>
> Neil
>
>
Au Contraire!
When mounted on a telescope for astro photography, Mirror Slap will wipe
you out.
Bob Williams
 >> Stay informed about: Mirror slap? 

In article <9JTPh.117202$p17.78006@newsfe11.phx>, Bob Williams
<mytbobnospam.TakeThisOut@cox.net> wrote:

> Neil Harrington wrote:
> > "William4" <w4.TakeThisOut@news.com> wrote in message
> > news:Q_PPh.20669$2F5.2684@newsfe5-win.ntli.net...
> >
> >>Assuming film - dig slrs are the same in this respect (but query relates
> >>to dslr);
> >>
> >>When does mirror slap, or whatever it is called today, show itself.
> >>Faster or slower shutter speeds or does it really 'all depend',
> >>I.a. is it a pretty quick event that I might see at very high speeds and
> >>has little impact (relatively) at low speeds,
> >>or a slow one that might be a problem with longer exposures.
> >
> >
> > With modern SLRs I don't think mirror slap is a factor to be concerned about
> > at any shutter speed.
> >
> > Neil
> >
> >
> Au Contraire!
> When mounted on a telescope for astro photography, Mirror Slap will wipe
> you out.
> Bob Williams


Also, why would it not affect "modern" SLRs? It's a mechanical
vibration caused by a mechanical movement of a mechanical part - and
always has been.

AAMoF, I just experienced this last night - I was taking some long
shots (with a 500mm lens, non-stabilized) of a the Gray's harbor
Lighthouse at dusk/after dark. I had to use mirror lockup, because the
mirror caused enough loss of sharpness that it was easily seen at
normal viewing size on the rear LCD panel (didn't even have to zoom)
after the shot. Using lockup, the vibrations went away and I had no
problem.

--
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
 >> Stay informed about: Mirror slap? 

"Neil Harrington" <not.RemoveThis@home.today> writes:

> "William4" <w4.RemoveThis@news.com> wrote in message
> news:Q_PPh.20669$2F5.2684@newsfe5-win.ntli.net...
>> Assuming film - dig slrs are the same in this respect (but query relates
>> to dslr);
>>
>> When does mirror slap, or whatever it is called today, show itself.
>> Faster or slower shutter speeds or does it really 'all depend',
>> I.a. is it a pretty quick event that I might see at very high speeds and
>> has little impact (relatively) at low speeds,
>> or a slow one that might be a problem with longer exposures.
>
> With modern SLRs I don't think mirror slap is a factor to be
> concerned about at any shutter speed.

If that were true, modern SLRs wouldn't be needing the mirror lock-up
feature.

--
Måns Rullgård
mans.RemoveThis@mansr.com
 >> Stay informed about: Mirror slap? 

Måns Rullgård wrote:
> "Neil Harrington" <not DeleteThis @home.today> writes:
>
>> "William4" <w4 DeleteThis @news.com> wrote in message
>> news:Q_PPh.20669$2F5.2684@newsfe5-win.ntli.net...
>>> Assuming film - dig slrs are the same in this respect (but query relates
>>> to dslr);
>>>
>>> When does mirror slap, or whatever it is called today, show itself.
>>> Faster or slower shutter speeds or does it really 'all depend',
>>> I.a. is it a pretty quick event that I might see at very high speeds and
>>> has little impact (relatively) at low speeds,
>>> or a slow one that might be a problem with longer exposures.
>> With modern SLRs I don't think mirror slap is a factor to be
>> concerned about at any shutter speed.
>
> If that were true, modern SLRs wouldn't be needing the mirror lock-up
> feature.
>

You still need the mirror lock-up to clean the sensor
 >> Stay informed about: Mirror slap? 

Zen Diver <spicedhamme DeleteThis @yahoo.com> writes:

> Måns Rullgård wrote:
>> "Neil Harrington" <not DeleteThis @home.today> writes:
>>
>>> "William4" <w4 DeleteThis @news.com> wrote in message
>>> news:Q_PPh.20669$2F5.2684@newsfe5-win.ntli.net...
>>>> Assuming film - dig slrs are the same in this respect (but query
>>>> relates to dslr);
>>>>
>>>> When does mirror slap, or whatever it is called today, show itself.
>>>> Faster or slower shutter speeds or does it really 'all depend',
>>>> I.a. is it a pretty quick event that I might see at very high
>>>> speeds and has little impact (relatively) at low speeds,
>>>> or a slow one that might be a problem with longer exposures.
>>> With modern SLRs I don't think mirror slap is a factor to be
>>> concerned about at any shutter speed.
>> If that were true, modern SLRs wouldn't be needing the mirror lock-up
>> feature.
>
> You still need the mirror lock-up to clean the sensor

It has nothing to do with sensor cleaning. For sensor cleaning the
mirror must be raised and the shutter opened. The mirror lock-up mode
raises the mirror without opening the shutter in order to allow
vibrations from the mirror to settle before the shutter is opened.
This makes a visible difference in some extreme conditions.

--
Måns Rullgård
mans DeleteThis @mansr.com
 >> Stay informed about: Mirror slap? 

I recall reading somewhere that it's an issue at "moderately long"
exposures, say, 1/2 ~ 1/30 seconds. At faster or slower speeds, the
amount of exposure that occurs when the camera is vibrating is
negligible. However, I can't recall the reference, and I haven't
checked it out for myself.

My Nikon D80 doesn't have a mirror lockup, per se, but it has a
feature that delays the shutter release for 0.4 seconds. I presume
that Nikon's engineers had some reason for implementing it that way...

On Sun, 01 Apr 2007 15:13:52 GMT, "William4" <w4 DeleteThis @news.com> wrote:

>Assuming film - dig slrs are the same in this respect (but query relates to
>dslr);
>
>When does mirror slap, or whatever it is called today, show itself.
>Faster or slower shutter speeds or does it really 'all depend',
>I.a. is it a pretty quick event that I might see at very high speeds and has
>little impact (relatively) at low speeds,
>or a slow one that might be a problem with longer exposures.
>

--
jackmacMACdonald DeleteThis @telusTELUS.net
remove uppercase letters for true email
http://www.geocities.com/jacksonmacd/ for info on MS Access security
 >> Stay informed about: Mirror slap? 

Måns Rullgård <mans.RemoveThis@mansr.com> wrote in
news:yw1xodm813ji.fsf@agrajag.mansr.com:

> "Neil Harrington" <not.RemoveThis@home.today> writes:

>> With modern SLRs I don't think mirror slap is a factor to be
>> concerned about at any shutter speed.
>
> If that were true, modern SLRs wouldn't be needing the mirror lock-up
> feature.

.... and I wouldn't have to compose 1/2 frame too low when using my 100-400
IS with 2x worth of TCs.


--

<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<>
John P Sheehy <JPS.RemoveThis@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><
 >> Stay informed about: Mirror slap? 

Zen Diver <spicedhamme.DeleteThis@yahoo.com> wrote in
news:Hemdnb0tld6vf5LbnZ2dnUVZ8qXinZ2d@pipex.net:

> You still need the mirror lock-up to clean the sensor

That can be dangerous, as some cameras cancel mirror-lockup after a number
of seconds.

--

<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<>
John P Sheehy <JPS.DeleteThis@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><
 >> Stay informed about: Mirror slap? 

In article <HI2dndKJuoXIS5LbnZ2dnUVZ_vyunZ2d.RemoveThis@comcast.com>, Neil
Harrington <not.RemoveThis@home.today> writes
>
>With modern SLRs I don't think mirror slap is a factor to be concerned about
>at any shutter speed.
>
Get real - if anything, mirror slap is a lot worse on modern AF cameras
with their double mirror arrangements than it ever was with a
conventional MF film camera.

I moved from Olympus OM to Canon 5D about 18 months ago and initially
thought that the extra mass of the 5D and Canon glass over the light OM
bodies and lenses would reduce the effect of mirror slap. In fact, it
is worse - a lot worse.

Astro photos I took with an OM-4Ti (which had a double mirror to enable
spot metering) were impossible to reproduce on the 5D even after locking
the mirror up because even the shutter slap on the Canon is worse than
the mirror slap on an OM, despite the Canon being more than double the
mass.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
 >> Stay informed about: Mirror slap? 

This message is not archived
 >> Stay informed about: Mirror slap? 

On Apr 1, 10:08 pm, M-M <nospam.... DeleteThis @ny.more> wrote:
> In article <9JTPh.117202$p17.78...@newsfe11.phx>,
> Bob Williams <mytbobnos... DeleteThis @cox.net> wrote:
>
> > When mounted on a telescope for astro photography, Mirror Slap will wipe
> > you out.
>
> Absolutely true. But the shutter delay of .4 sec on the Nikon seems to
> work well.
>
> --
> m-m

My recollection from literature about vibration reduction is that
about 1/15 sec tends to generate the most vibration and blur. For
astro photgraphy local ground level winds also have an effect.

Astrophotography is more and more being done through compositing
multiple images taken more or less like those from a video camera.
Some companies are selling the equivalent of a video camera lens that
mounts directly to the scope, and requires an attached computer to set
the scope focus, etc.

But for moon shots and star trails, traditional style (including
digital) cameras work just fine. Do watch for noise increases with
longer exposures as electronic noise will increase as the sensor warms
up from continuous use. Subtracting a black frame may make a
diffference by elimating the "hot" pixels..

Joe
 >> Stay informed about: Mirror slap? 

On Apr 1, 6:11 pm, Kennedy McEwen <r... RemoveThis @nospam.demon.co.uk> wrote:
> In article <HI2dndKJuoXIS5LbnZ2dnUVZ_vyun... RemoveThis @comcast.com>, Neil
> Harrington <n... RemoveThis @home.today> writes
>
> >With modern SLRs I don't think mirror slap is a factor to be concerned about
> >at any shutter speed.
>
> Get real - if anything, mirror slap is a lot worse on modern AF cameras
> with their double mirror arrangements than it ever was with a
> conventional MF film camera.
>
> I moved from Olympus OM to Canon 5D about 18 months ago and initially
> thought that the extra mass of the 5D and Canon glass over the light OM
> bodies and lenses would reduce the effect of mirror slap. In fact, it
> is worse - a lot worse.
>
> Astro photos I took with an OM-4Ti (which had a double mirror to enable
> spot metering) were impossible to reproduce on the 5D even after locking
> the mirror up because even the shutter slap on the Canon is worse than
> the mirror slap on an OM, despite the Canon being more than double the
> mass.
> --

My experience with the OM cameras was they always seemed to have very
little vibration. Perhaps it was they way the balanced the system -
who knows? But I once did a test between my OM2s and my fathers Pentax
Spotmatic F, by balancing a nickel on it's end at the end of a
telephoto lens and then releasing the shutter with an extension. With
the Pentax, the nickel fell of, but not so with the OM2s. We were all
pretty impressed! But for the little bit of astrophotography I did
with my later OM4, I used the self timer which locked up the mirror at
the start of the timer, then ran the shutter after the countdown.
Seemed to work well. However, I had a bugger of a time trying to focus
the damn system!

My experience is that mirror slap is more of a factor for shutter
speeds of 1/15 down to 1" or so. Longer than that, the movement takes
place over a very small percentage of the actual exposure. Then with
shutter speeds of 1/30 or faster, the shutter isn't open long enough
to be affected by the mirror slap.

Karl Winkler
http://www.karlwinkler.com
 >> Stay informed about: Mirror slap?