shake reduction, on or off

[davidhampshire]

just wondering about the shake reduction feature,    been experimenting a little bit,  not much,   with leaving the shake reduction on the k-5 off,   hand held shots,    i seem to be getting a better,  more clear photo,   most of the time ,   ( using the dfa 100 wr )  with close and macro,   manual focus ,   wider apertures  --  does the s r  affect the photo,   i know it's recommended to turn off the s r for tripod shots.    but in general?           

[spyglass]

Hi David,

I do not use it very often (probably because I tend to pack a tripod around), but when shooting free hand with longer lenses, or under slower shutter situations it is a tool worth using.

I remember an old photography teacher once offering a rule of thumb when using longer lenses (lenses 50mm and up). He said to always select a shutter speed greater than the focal length of the lens being used. For example if you were shooting a 100mm lens you would select a shutter speed 1/100th (1/125) or faster. If you were shooting a 200mm lens you would select a shutter speed 1/200th (1/250th), or for a 400mm 1/400th (1/500th). While I believe this to be good food for thought and a good way to introduce the issues surrounding exaggerated movement with increased focal length..... I suspect that he also looked for any helpful tip that might reduce film and paper waste in his classroom. I think one could adapt his lesson to suggest that one might consider using shake reduction anytime the focal length exceeds the shutter speed.  


Spyglass

[Pacerr]

. . . offering a rule of thumb

The earliest "thumb rule" was ALWAYS use the best thing available at the moment to steady the camera under ALL conditions. There's no batteries required when using a fence post or the back of a chair for "mechanical SR". Searching for a spot that provides a good steady rest is a finesse-point when selecting a shooting position.

When you used ASA 25 film, ambient light and a steady hand had a whole different meaning. One has to marvel at the folks shooting at ISO 12,000+ while using SR and still whining about camera shake as they wave the camera about at arms length. 

Regardless of your feelings about firearms, it pays to research/review the basic instructions about steady shooting positions, trigger (shutter) control and breath control in competition shooting sports -- that's hand-holding technique to the max.

Someone more energetic than I can calculate the relative "blur-factor" for acceptable critical sharpness and winning accuracy between a 400mm lens and a minute-of-angle, five shot group at 500 yds. 

H2




 

[blackcloudbrew]

Spyglass has some excellent points. Clearly, when on a tripod (make that stable tripod), SR should be off otherwise you images will be affected by SR. I also agree that with telephoto lenses keeping the shutter speed higher than the focal length of the lens is the way to go as well. For me though, I work a lot with hand held shots and so SR in the ON position is my preferred way to go. If you see it different in you images then do what you see or think best. The studies of the in camera SR systems that I've read do say that it works and gives you at least a 1 stop improvement in camera performance. The same studies also say that beyond about 150mm in focal length, SR can't effectively compensate for movement. Other manufactures who use in-lens vibration compensation systems do have an edge in longer telephoto lenses over the in-camera system used by Pentax and Sony. A question you didn't ask but is related here it what do you do if you have a lens with a vibration compensation system mounted on a Pentax with SR? The answer is pick with one system will be on. You can't use both. Note: Sigma makes some lenses in k-mount with vibration compensation built in.

Anyway, I believe the the Pentax SR system is brilliant in that any lens mounted on the camera can be used with it and that it allows me to get more shots off the tripod than on it. $0.02

Earl