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mr.voigtlander · 02-08-2008, 06:34 AM

Hi,

What's the use of shake reduction and a long telephoto lens (400mm, 500mm, 600mm) if you can't use it on a tripod? Why does it have to be turned off?

Any other user comments on using SR with long telephoto lenses?

Does shake reduction work on bulb setting?

Thanks

**SCGushue** · 02-08-2008, 06:46 AM

Originally posted by mr.voigtlander

Hi,

What's the use of shake reduction and a long telephoto lens (400mm, 500mm, 600mm) if you can't use it on a tripod? Why does it have to be turned off?

Any other user comments on using SR with long telephoto lenses?

Does shake reduction work on bulb setting?

Thanks

Shake reduction is of value through 800mm (The Pentax focal length feature does not exceed that for obvious reasons) and in rare instances these lenses are hand holdable and images of quality can be captured.

Use of a tripod itself should not require utilization of shake reduction. Tripods are build for certain weight load restrictions. Some tripods can only handle 4 to 7 pounds worth of accumulated gear. Other tripods can hold 40-60 pounds worth of gear without torsion.

Further, when you use super telephotos you should have the appropriate gear to mount the lens such as a Wimberely head, or a sidekick that allows for both stability and XYZ panning.

I use 400mm lenses handheld quite often, and with shake reduction I have captured acceptable images at 1/8th of a second. Not my choice of shutter speed but sometimes conditions warrent extreme measures. When I use my Pentax 1000mm and 1200mm lenses they require solid platforms and expensive hardware. Since this is backwards compatible I only need one top notch head and tripod.

A good tripod is invaluable.

Stephen

Confused · 02-08-2008, 06:49 AM

Hi mr.voigtlander

Try reading the info contained in the link below:

https://www.pentaxforums.com/forums/pentax-dslr-discussion/5104-k10d-shake-re...on+with+tripod

Hope this helps

Best regards
Richard

mr.voigtlander · 02-08-2008, 07:27 AM

I use a Benbo tripod - the big one - with a 500mm f5 lens. When shooting wildlife in good light (ie not always bright!) shutter speeds get down and you still get camera/lens shake on a tripod.

For me the main attraction of using a Pentax digital camera with a 500mm lens would be this shake reduction. But maybe it's not much use here after all.

What about using it on a monopod? I'm not trying to get shake. But I know that for the conditions I shoot in with a long lens, you do get camera shake, and an image stabiliser system is a great advantage.

By the way, the lens is on the tripod (on a collar), not the camera. So can I cheat!

hmmm. Maybe I'll stay with film a bit longer yet. If you're shooting landscapes on tripod - yes turn off shake reduction. But for a 500mm or 600mm lens that's something you'd want.

Anyway, thanks for the info and links.

Jodokast96 · 02-08-2008, 07:41 AM

It doesn't have to be turned off. But if the platform is super steady, it's believed that the SR can actually cause shake by trying to correct movement that isn't there. If you are still getting shake with a tripod, by all means try turning it on

Confused · 02-08-2008, 07:46 AM

Hi again

Here is a previous quote from Lowell:

Quote:

While people have written in that if you are on a tripod there is no need because the camera is stable, I am not sure that they have ever looked through a 500mm-1000mm lens on a tripod. There is all sorts of vibration, much of it very high frequency. This is why lots of pros use a sand bag to weight down the tripod.

Best regards
Richard

Busiko · 02-08-2008, 08:59 AM

Originally posted by mr.voigtlander

Hi,

What's the use of shake reduction and a long telephoto lens (400mm, 500mm, 600mm) if you can't use it on a tripod? Why does it have to be turned off?

Any other user comments on using SR with long telephoto lenses?

Does shake reduction work on bulb setting?

Thanks

Unless you are deep frozen outside on a hard winter's day you will always shake yourself a bit. A shake reduction system cannot correct that shake instantaneously the moment you shoot. So it has to correct in advance. It's called Predictive correction. Once you half press the shutter release, SR will understand what measure is your shake and apply a correction. If your shake is e.g. +1 the SR system will correct with a value equal to -1, so the result is 0.0 The moment you mount a tripod with SR on, the system predictively will apply a correction amount that depends on the Focal length of the lens. As the real shake is 0.0 because of the tripod steadiness, the result would be negative causing the sensor to shake more than expected on the wrong direction.

Rui

roscot · 02-08-2008, 10:52 AM

Statement about not using SR with a tripod assumes a steady mount. If you are still getting camera shake on your tripod, go ahead and use SR. Also definitely use it with a monopod.

little laker · 02-08-2008, 11:17 AM

This'll give you an idea that SR does work.

I took this picture with a 50mm f2.0 from in my 8 foot long boat. So you know that it was rocking.

That brown spot about 2/3 of the way across and right above the water was a deer eating.

So I snapped on my Sigma 135 - 400, and took this picture.

Here's the cropped version, giving you an idea how steady everything appears.

It was taken shortly after daybreak, so it was darker than I'd have liked, ISO 200, at f5.6 and I don't know what the shutter speed was other than slower than I would have really liked.

As you can probably imagine that shot would have been rather tough without SR, or a higher ISO.

PePe · 02-08-2008, 11:34 AM

I often use my long lenses with a monopod. I always have SR on, and it works very well. Cannot think of a single reason for not using it.

Andrew Faires · 02-08-2008, 01:42 PM

I use s/r with a tripond and long lens. My logic being that while the camera may be on a tripod, because I'm holding the camera (and trying to dampen lens vibration by keeping my hand on the lens over the tripod collar), I'm still introducing some vibration.

I'd say it's a pretty potent combination too. I generally had to give up if the shutter speed dipped below 1/60th of a second with my 400mm and DS2 on a tripod (admittedly, not the most robust tripod out there), but using the SR on the k10d active & using a tripod, I can eek out a 1/30th sec. exposure:

1/30th, f/5.6, tripod, s/r active. Originally shot horizontal, cropped to verticle.

Tuoppi · 02-08-2008, 02:15 PM

Minus -10 celcius. Pentax K100d+Tamron Adaptall-2 SP 300 and 2Xteleconverter http://koti.phnet.fi/valokuvia/Pentax/IMGP2303.jpg

Originally posted by mr.voigtlander

Hi,

What's the use of shake reduction and a long telephoto lens (400mm, 500mm, 600mm) if you can't use it on a tripod? Why does it have to be turned off?

Any other user comments on using SR with long telephoto lenses?

Does shake reduction work on bulb setting?

Thanks

falconeye · 02-08-2008, 02:34 PM

Originally posted by Confused

Try reading the info contained in the link below:
https://www.pentaxforums.com/forums/pentax-dslr-discussion/5104-k10d-shake-re...on+with+tripod

Have read that other thread and the thread here as well. Interesting topic!

But besides the reports about experiences made, everything is just speculation. It may however, be worth the effort to find out how the Pentax SR really works.

Just a general comment: as long as the gyro sensors don't measure acceleration, the SR will remain mute and it most probably makes no difference. Stable tripoid assumed. Stable tripoids can be found in astro photography...

I do not know the following factors:
- Does the Pentax SR measure 2, 3, or 6 axes of motion?
- What is its resolution (minimal, maximum and delta in m/s^2 and 1/s^2 resp.)?
- What is the Eigen frequency of combined system gyro, electonics, sensor-drive?
- Does the algorithm apply frequency-decomposition with phase shift, or does is work in the time domain?

If I would, I could answer some of the questions. For instance, it could be that some of the tripoids' vibration frequencies are too close the SR system's Eigen frequencies. If this is the case, using SR could be very counter-productive indeed.

But even then, a tripoid's Eigen frequencies will depend on the tripoid itself, the length of legs and the weight of gear mounted. So, by knowing more it may be possible to use SR with tripoids to one's advantage -- or by educated experimentation (e.g., frequencies of shake can be measured with laser interferometers...).

To conclude, I can make one recommendation:
If the subject does not move, use a tripoid with SR off to shoot a long sequence (~ 100) of (underexposed) images and stack them together using one of those open source software packages used to stack astrophotography images. This provides SR by software.

distudio · 02-08-2008, 06:49 PM