does the mirror slam give blur even on a tripod?

[andreatau]

Hi all

 

I was wondering if the mirror lock up button (or whatever it's

called) can *indeed* improve the final quality *even* if the camera

(Hassy 500CM) is fixed on a very sturdy tripod *and* fired by cable

release. The reason for my question is that I find it often annoying

to lock the mirror up when shooting people who are not posing still

but spontaneously doing their businness (e.g. a sculptor...) and

that, of course, due to the disappearance of the scene in the

focusing screen which does not let you know what you're actually

shooting until you see the print! So closed eyes, awfull face

expressions not rarely come out... Does anyone have opinion? Thanks a

lot and yes, I'm not a master of medium format yet :)

[garry edwards]

At long shutter speeds, yes.<br>But I did a fashion shoot last week, RZ67 (larger mirror than yours), hand-held at 1/30th with no problems.<p>There is in fact an argument that most tripods can actually <i>add</i> to shake caused by mirror slap because they set up their own vibrations and transmit the vibrations caused by the mirror slap, in much the same way as a tuning fork. When the camera is hand-held the vibrations are absorbed, to some extent, by the photographer's body.<p>Personally I don't use mirror lock-up with speeds above 1/30th and live subjects.<p>Hope this helps

[lex_jenkins]

A few years ago Herb Keppler did a test for Pop Photo to evaluate the effects of mirror lockup and lack thereof on photos taken using tripod mounted cameras. Granted, the test involved only 35mm SLRs, but the fundamentals are valid for any camera.

 

Basically, the test determined that mirror lockup is effective mostly for shutter speeds between around 1/4-1/60 second. Faster or slower and the benefit diminishes rapidly.

 

Simply using the tripod already provides significant benefits. If mirror lockup interferes with composition, what good is a poorly framed or timed image that's otherwise technically excellent?

 

I use a tripod for all of my cameras more often now mostly due to a back and neck injury that makes it difficult to hold as steadily as once I could. But I definitely do not always use mirror lockup, especially with fairly fast or very slow shutter speeds and never when people are an essential part of the image.

[stephen hazelton]

Try it both ways. If you can't see a difference, there's not a difference! Theoretically, there should always be some effect, but it may be so minor as to be meaningless.

[skygzr]

Take a laser pointer and tape it to your camera. Aim it at a mirror across the room, so that the dot ends up back by you (you�ll have to come up with some way of keeping the thing turned on without touching it). Fire the shutter and look to see if the dot dances. A 30� lever is a pretty good vibration amplifier; you should be able to see if a particular camera/tripod combination is susceptible to shake.

 

This only tells you something if the dot doesn�t move at all; it just means that you don�t need to worry about shutter slap. You can also experiment with various methods of minimizing vibration, such as putting a beanbag on the camera (try it!).

 

Soon, of course, we�ll have the Mirror Slap filter in Photoshop, and we won�t have to worry about it.

[david_goldfarb]

It also depends on the mass and design of the tripod and the head. Some tripods may vibrate sympathetically with a particular camera and others may not.

[andreatau]

Hi folks

 

Let me first thank you all for the useful inputs. I�ve just tried the experiment suggested by Kevin. After taping the laser pointer on the camera and firing different modes here are the (startling) results:

 

-if the camera is handheld, the laser dot shakes by at least 2 millimetres (at a camera-to-wall distance of 2 metres) **even without shooting at all**!! The dot springs by one centimetre as soon as I fire without mirror lock-up. B.t.w., I�m 30 years old and do not drink coffee but have never been in the Army!! Another b.t.w.: 1 centimetre versus 2 metres means that If the subject were 100 metres away my laser dot would shake by as many as 50 centimetres (20 inches), I guess some bow practice would help!!

 

 

-when the camera is both mounted on my sturdy tripod *and* fired by cable release, the laser dot is shaken by approx. a half millimetre due to mirror slap (at the same distance from the wall of about 2 m).

 

 

-With camera on the tripod, cable release *and* mirror lock-up� no shake at all.

 

I should have thought of this experiment before, or maybe not: I will never dare to shoot handheld again!! Thanks indeed, cheers

[skygzr]

Hi Andrea �

 

I�m glad you performed the experiment, but don�t let it stop you from ever shooting handheld again! It may well be that 2mm of blur (or whatever) may be completely acceptable for a given print size. After all, it�s not the linear displacement that matter the most, but how big that displacement appears on the final print. Many thousands of perfectly fine photographs have been taken handheld!

[tom_westbrook]

Actually, a more useful test would be to aim the laser pointer at the wall in front of the camera & take a picture of the dot under the different methods you used. Tape a ruler to the wall to get your measurements. That way you can measure the pointer movement during the time the shutter is actually open.

[andreatau]

Yeah, of course one thing is the linear display that I have witnessed, another is how this 'shake' will eventually affect the picture, which depends on enlargement, focal lenght of the lens one uses, camera-to-subject distance, shutter speed and so on. Ok, I'll keep trying to shoot handheld (my sturdy tripod's wheight is even more discouraging than the shaking laser-dot!!!). Cheers

[q.g._de_bakker]

One tip regarding tripods resonating, amplifying camera induced shake: don't lock everything on the tripod head as tight as you can, but leave some (minimal) play. Doing so will prevent resonance, and, above that, absorb a lot of camera induced shake.

[chuck_hoffman]

Several years ago, Bob Atkins <a href="http://www.photo.net/nature/mlu">did this study</a> on the effects of mirror slap and plotted the results graphically. However, the results he obtained are only possible if some part of the camera and/or support is capable of producing a sympathetic response to a mirror-induced transient vibration.<p>If the tripod or other support is beefy enough or rigid enough, the mirror slap will be less noticable (or not noticable at all) because of a high moment of inertia relative to the force applied.<p>Another way to minimize mirror slap...as has been mentioned...is by the use of a non-resonant (vibration absorbing) material like a beanbag, a human hand (braced or supported to remove neural or muscular unsteadiness), a pad of non-rigid closed-cell foam, etc.

[q.g._de_bakker]

Rigidity in a tripod is not the (complete) answer. Tripods are not solid, uniform blocks, but have several pivotal, "nodal", points giving occasion to resonance. Like i indicated in my previous reply, what often helps to minimize the effects of camera induced shake is lack (!) of rigidity. So don't lock your tripod head as tight as you can.(Same principle as bean-bags).

[c-p-j]

Andrea,

 

Following a suggestion on this board over a year ago, I have often stabilized the tripod-mounted Hasselblad by holding it with both hands and exerting a downward pressure on the tripod at the same time. It seems to work, but if you already have your laser set up perhaps you could provide an answer at 1/30th, 1/15th or 1/10th?

[andreatau]

Hi all again

 

Glad to see that the topic is interesting to many. The Manfrotto tripod I am currently using has followed at least 3-4 other models during the last 6 months. Unfortunately this is also the heaviest (around 3 kg) but it does finally eliminate the main source of vibration that I had noticed in the previous ones, more a matter of head than of tripod itself. In my case it was mostly due to the flexibility of the plate on which I block the camera, very evident if the plate is only held and connected to the rest of the tripod head on *one* side (forming a 90° angle, usually) *and* the material is lightweight such as plastic or aluminum. I guess sphere heads are not affected by this problem, though I don't like them for other reasons. On the other hand, a sturdy tripod itself is more important to prevent the heavy medium format system from tipping over and crashing, as well as in case of wind. As a result... it's unavoidable to carry along considerable weight when using MF systems, but in Italy we have a said: "you wanted a bicicle, now you've got to pedal".

 

I had not thought about the opportunity not to block the head as much as you can, but it sounds reasonable. I also have the feeling that pushing down the camera against the tripod may help stabilise it especially, but not only, if the wind is blowing like hell: I guess you reduce the effect of the shaking gust's force by applying a stronger and constant one downwards, which increases the camera weight in all respects. So I have now tried to use the laser pointer once again to see if I could qualitatively detect any improvement brought by this tip. The results have been very different from one shot to another, roughly indicating that the downwards pressure does help if one's really able to keep it constant, otherwise it becomes counterproductive (so it must be for me, as the largest percentage of shots gave either no effect or a negative one).

 

Well, my main concern is now how to prevent blur when shooting handheld, given the worrying results of my early laser test! If you observe the laserdot on the wall you'll see it shaking more than expected even while simply aiming the subject! But the question is: what's the slowest speed that safely prevents that motion from showing on film as blur (for instance when shooting portraits at close distance)? And I guess all have opinions about that, though the only way to find it out is to do the laser test shooting with film at 1/125th, 1/60th, 1/30th... and print it! I'll probably do it (after I buy new batteries for the laser!). Then I'll let you know... Thanks again for the tips, cheers

[dick roadnight cotswolds]

Do you remenber the days when the standard Hasselblad viewing system included a wire frame viewer?

 

... great for hand helds with the mirror locked up!

[q.g._de_bakker]

Dick asked:

 

"Do you remenber the days when the standard Hasselblad viewing system included a wire frame viewer? "

 

I don't. Not quite as a "standard" item, that is. ;-)

 

The "standard viewing system" was the well known focussing hood with loupe, first on a stilt, later on a plate.

 

Frame viewfinders, taking masks for different focal length lenses longer than 80 mm, that fitted the 1600F and 1000F "flash shoe" and the later 500 series accessory shoe were next. And the non-folding "chimney" finder.

 

A 90 degrees prism was the next addition to the "viewing system", and at the same time a combination prism/frame viewfinder (with mask) appeared.

Many more prisms followed.

 

And yes, there was a frame viewfinder that fitted on the lens hood, which did not take masks, but had a rubber band to indicate a smaller format. It could be used with 150 mm and 250 mm lenses only, and using an extra attachment with 350 and 500 mm lenses too.

"Standard"? ;-)

[c-p-j]

ANDREA,

You summed up the essence of the question very clearly: " what's the slowest speed that safely prevents that motion from showing on film as blur. . . I guess all have opinions about that, though the only way to find it out is to do the laser test shooting with film at 1/125th, 1/60th, 1/30th... and print it!" IF YOU DO THE TESTS, IT WILL RESOLVE A LOT OF TRIPOD, Pan Head, Ball Head, Mirror Slap, cable release, etc. questions which have been posted on this board for the past two years with nothing but "opinions" to back up "theories" which sometimes originate in "dreams." Hard evidence is what we need, so take careful notes. Thanks from all of us!