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ABOUT TRIPOD, HEAD AND VIBRATION

MARCH 2005

ameter. Let this be the starting point of our ar- gument of vibration analysis. The support system should perform at least the level of the minimum pixel size of the given camera image sensor or film resolution.

Handheld Shooting, Fast Shutter Speed

From above results, following argument can be drawn. Sometimes human oriented vibration is much bigger than the one caused by camera mechanism. A human oriented vibration means a shake by operator who is surprised by a sud- den sound or shock by shutter and mirror.

Holding a camera stable is not easy, even we want to believe that sometimes we could hold it stable. I had no idea how good one could hold. So Mr. Mah, CEO of Markins 5 and me, tried handheld shot using Leica R6.2 with Apo Macro 100mm f2.8. The first graph was my data and the other was Mr. Mah’s. These are the best results from us on that day. Mr. Mah held his breath perfectly in good posture while taking the data

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It's widely accepted that the shutter speed, if handheld, should be faster than 1.5~2 times the angle of view of the lens, i.e., use at least 1/125s for 50mm lens and 1/250s for 180mm. By using faster shutter speed, the effect of vibration could be reduced.

Handheld Shooting, SLR vs. RF camera

I’ve used many RF cameras including Leica M6, black-dial IIIf and legendary Leica M3. Each of my Leica M was also equipped with the soft re- lease 6 , which really works. Even the way one presses the shutter matters when you are in the realm of RF cameras.

We normally expect a sharper picture in RF camera. But having no mirror is not the only rea- son. There are more dominant factors such as shorter ray travel length, tighter tolerance be- tween assembly, less moving part, etc. The dis- tance from front lens to the film is much shorter than SLR camera. Because RF camera uses ma- nual focus lens, it can be built to have more tight tolerance than usual AF lens.

Some SLR cameras have bigger mirror shock and this causes an unconscious reaction. Some- times this human oriented vibration is bigger than the actual vibrations caused by mirror. You may feel quite a strong shock in Leica R series camera but most of the shock is due to the mir- ror down shock that is irrelevant to photo quality.

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http://rapidwinder.com/#softrelease

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I’ve used some of the Contax RTS 7 series which has no middle stages in shutter pressing action. For me, it was harder to get to know the exact timing of shutter firing compared with most me- chanical shutter. However, most SLR cameras are good if they are used in handheld condition. Usually the mirror shock itself does not make much difference in handheld condition.8

Handheld Shooting, Vibration bracketing

So if I have to shot without tripod, I sometimes try vibration bracketing. Just like doing focus bracketing or exposure bracketing. But it’s al- ways better to get your tripod. You only have two legs, only the weird lady at the beach near Manfrotto logo has three legs.9

MAIN

Most of the experiments were done in well es- tablished environment, so the actual magnitude of vibrations could be greater by more than three times in the field environment. And please do not try to compare results in different envi- ronment even the systems used are identical.

Resolution or Sharpness

I have to start this journey with some talks about resolution. When we do talk about sharpness about the photo, we’re also considering the contrast. But if we talk about resolution, it be- comes something simply mechanical.

7 8 Contax RTS I, RTS II, RTS III, RX Recent Olympus EVOLT E-300 has mirror which oper- ates in horizontal direction. I become very curious about the feel of this kind of configuration as I guess the response of that camera will be a bit different.

9 On page 51 of American PHOTO March/April 2005 issue

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