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03-01-2010, 05:16 AM   #16
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at what focal length?

I think you need to consider focal length also in this question.

1/40th with a 28mm or 35 mm is no big stretch.

but what about with 500mm and 1/40? this is a 100% crop out of a full frame shot with my k7. conisdering crop factor of the sensor the old rule of thumb suggests this should be shot at 1/750th not 1/40th.





03-01-2010, 06:22 AM   #17
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Not counting the SR of the K10D, I can typically make steady shots as low as 1/4s, film or digital. Typically, though, I try not to go below 1/8th. This is, of course, with pretty standard focal lengths (between 28 and around 90 or 100mm).

My friend, who has an LX, says he can't shoot steadily handheld lower than 1/30.
03-01-2010, 08:04 AM   #18
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I'm with Lowell on focal length. In fact I'm scratching my head over the purchase of a lens for low light based on the potentially superior performance of wider angle lenses. I'd be curious as to anyone else's experience.

Bear with me here. I have an FA 50 1.4. The reciprocal rule (well, anyway, one interpretation of it) suggests this would optimize at 1/50th of a second.

I'm thinking about buying an FA 35 2.0, but the aperture wise, it would seem to be a good deal slower than my 50. However, the reciprocal rule suggests its shutter speed optimizes at 1/35 of a second. So in terms of being able to shoot stills in worst case low light, it's operationally more like a 1.8, which ain't all that bad, especially since the 50 likes to be stopped down a tad.

Now if we go with say, an SMC Pentax-A 28mm F2, we're talking about 1/28, which is pretty close to the 50 when you combine shutter and aperture optimization.

I really don't know if this is a valid analysis, there may well be some law of diminishing returns. I may try some experiments with the Sigma 10-20. With SR on, I should be able to hand hold that at 1/5 sec at f3.5.
03-01-2010, 08:38 AM   #19
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I typically find 1/FL is quite safe.

I typically find I can get as low as 0.3*/FL without too many issues.
1/5 @ 16mm...
1/15 @ 50mm...
1/40 @ 135mm

any lower and I start to have issues... on a K20D

of course... you need a static subject to shoot at 1/5

03-01-2010, 09:00 AM   #20
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About 1/10th of a second with my 16-45 Pentax lens, using either my K10D or KM.
03-01-2010, 09:22 AM   #21
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Most normal lenses and wider, I'll go to 1/30 comfortably. Below that it's a gamble.
03-01-2010, 09:33 AM   #22
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QuoteOriginally posted by Alex00 Quote
1/FC is not enough for most users and will still result in slight blur if you Pixel peep.
I'd say a couple of things are going on here. One, the old rule of thumb (which most would indeed state as 1/FL) was for "FF". Because the effect of camera shake is dependent on FOV not focal length per se, you would want to apply the crop factor, yielding 1/(1.5xFL). But the second is also relevant - the old rule of thumb was to avoid blur that would be noticeable in typical prints - it was never meant to guarantee results that would stand up to pixel peeping. So I'd agree with you that most people probably tend to be overly optimistic, and would be better off assuming 1/(2xFL). If not for SR, anyhow.

It's also important to realize these are just rules of thumb - numbers kind of pulled out of a hat to yield what someone thought of as giving a "typical" person a "decent" chance of a sharp "enough" shot. And results also depend on how well you re able to brace yourself physically

My personal best shot in practice is this, taken at 100mm (M100/2.8) and 1/6, but I was able to lean against a counter and prop up my elbows:



BTW, this isn't about lenses *at all*, so I've moved it to the DSLR forum.
03-01-2010, 09:35 AM   #23
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QuoteOriginally posted by Ash Quote
The sweet spot for me at 50mm with SR is about 1/15 sec.
This works for me, too. Any slower and your subject might move away. This is for taking pictures inside with very little available light.

It's not desirable, but sometimes you really need to push the limits of your camera/lens.

This is at 1/15 sec. f2.4 iso 1600 with 50mm A1.4 lens. I could have gone wider on the aperture, but I was having trouble focusing due to lack of light.

Here is a crop. It's been lightened for demonstration purposes. I can almost read the serial #.



Last edited by dragonfly; 03-01-2010 at 10:01 AM.
03-01-2010, 09:40 AM   #24
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QuoteOriginally posted by LouD Quote
I'm thinking about buying an FA 35 2.0, but the aperture wise, it would seem to be a good deal slower than my 50. However, the reciprocal rule suggests its shutter speed optimizes at 1/35 of a second. So in terms of being able to shoot stills in worst case low light, it's operationally more like a 1.8, which ain't all that bad, especially since the 50 likes to be stopped down a tad.
This is true, but if you crop your images from the shorter focal length to render your subject as large as with the 50, you'll have just nullified the advantage you got from the wider FOV. And if you don't crop the image, then you don't really have any more detail to show for for the reduction in blur in a similar-sized print or display. I suppose if you actually come in closer to shoot with the wider angle lens, then you'd actually see an advantage.
03-01-2010, 10:33 AM   #25
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Of course it's focal length dependent but on Pentax dSLRs with Shake Reduction I regularly manage 1/4 sec with success - it is by no means 100% but most of my shots do come out acceptable at minimum - please see this thread for examples -

Kx in Use

in that thread I also mentioned that I can manage hand-held down to 1 sec - but with my Canon PowerShot G10 compact.

The Canon in lens IS (Image Stabilization) could be better than the in-body sensor SR of Pentax - but the reason for me is the SLR (any) blackout when the shutter is tripped - whereas the Canon p&s has a simple optical viewfinder that I can follow-through keep my eye on the subject during the exposure. This is a very important aspect for longer exposures - and a weakness of any SLR.

Examples -

Pentax K-x

ISO5000, f/3.5, 1/4; 18mm
musicians playing off stage (in the dark)


ISO5000 f/3.5 1/4; 18mm - yes, I was lucky - most of my shots showed SR did its job - but had subject movement .

Canon G10 compact -

last shot may not seem such great shakes (actually operative word)...
but I looked at the EXIF data and realized that is a 1 sec exposure even at ISO800 - yes, I did say handheld
- I had my back leaning against a wall - both hands on camera pressed against my face (hence my mandatory optical viewfinder requirement) - but honestly handheld
- so I would say the IS (Image Stabilization) does work (and well!).....
EXIF data is attached but PhotoBucket can mysteriously lose metadata.
ISO800, f/2.8, 1.0 sec! 6.1mm (28mm equiv)

Here's the actual pixel crop of that part -

EXIF attached (PhotoBucket caveat)
There is obvious subject movement and also remember the shot is at ISO800 (on the G10 tiny sensor)
where there is quite a bit of softening/lose of detail due to the in-camera noise reduction.
- but one can still see that the stationary objects on stage are without blur.

Just had a thought -
that Canon G10 1sec shot would have been only 1/4 sec on the Pentax K-x
using my normal ISO max of ISO5000, 18mm, f/3.5 would need about 1/4sec for the same exposure
so in that way the Pentax K-x gives equal performance
even if I may not be able to handhold down to 1 sec
(which was/is ridiculous anyway!)

Last edited by UnknownVT; 03-01-2010 at 10:48 AM.
03-01-2010, 04:08 PM   #26
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here's one I just took (1/5s @ 115mm)

Happen to have my Kx + 50-135 in my hand so I snapped this one off (single shot only) of my wife before she noticed and gave me the "take one more picture of me and I'll kill you stare". Wouldn't have normally tried a shot like that with such a slow shutter speed, but I happen to have the camera in my hand in Av mode.

Anyway, it's not super sharp at the pixel level, but not too bad either considering the shutter speed was so slow. Straight out of the camera except for resizing.

Kx + DA*50-135 @ 115mm, 1/5s, f/2.8, iso 1600
03-01-2010, 08:17 PM   #27
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As mentioned above, it depends a lot on focal length. It also depends on the lens. I have a lot better success rate with my limiteds as compared to my DA * lenses. I know some feel that heavier lenses help reduce shake, but I think smaller lenses help. The K20 is better than the K10. Shake reduction is a dangerous tool. It can let you shoot at shutter speeds you don't belong shooting at, just because you have SR.

This is a photo shot with the DA 35 limited at 1/6 second with the K10.



It is pretty steady, but if you would pixel peep, you could see a little bit of camera shake.
03-01-2010, 11:22 PM   #28
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Hi Alex,

I shoot mostly long tele, and I can pretty much rely on 2 stops slower than the 1/FL "rule". For 300mm, I can feel pretty confident at over 1/80, for 500mm -- 1/125 and I usually get a pretty fair share of acceptable shots. I always try to lean against something though. . . and this is with SR

My record, though was a 1 sec shot at 18mm -- standing, braced against a door jamb -- I don't even attempt this very often though. . .

Scott
03-01-2010, 11:33 PM   #29
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I have got some ok shots at 1/10 and 1/15 but wouldn't want to have them printed at large sizes. Haven't really tried out some real slow shutter speeds while hand holding. Might give it a test out one day.
03-01-2010, 11:43 PM   #30
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I have 5 photos posted in the "post your photos" under the title "Pub Night" which are all at 1/3 and 1/5 seconds....a little soft, but hey, its was very low light and you can only get so much when its that slow. I think they turned out nicely though.

Jason
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