Image Stabilisation

[TheAnimus]

Whilst playing with my 100mm prime, I figured I was doing an amazing job of holding it steady, so I decided to turn off the stabalisation, to see what the effect is.

The sharp image was taken at 1/25th with in body stabilisation turned on, the 1/30th was taken with no in body. I tried to make the test as fair as possible, both were taken wide open at f2.8, 1600 ISO.

I decided to do this test just because I'd been playing with the macro lens at night, the old idea of 1.5 times focal length meant I should have been shooting at about 1/150th. What is really making me want to do some more testing is how comparatively useless I've found the Optical Stabilisation in my lenses to be.

As for this little test, both shots were hand held, so there would be some variance, still I think that for a 100mm shot, at 1/30th its a very respectable amount of drift.

[g8ina]

Not too shabby at all that What kit is this again - Sony by chance ?

[Bobster]

with practice, you won't need IS

[TheAnimus]

with practice, you won't need IS

Utter horse ****.

The demo nicely shows that I can get extra performance from having the in-body stabilisation, it isn't to say practice makes perfect, but more that stabilisation allows you to do better than you otherwise would have. In this case I'd probably be looking at ISO 6400.

Now, if I practice more and can hold a 1/25th without IS, my still subject would benefit from the lower ISO. This is 100mm remember, and the subject wasn't exactly on top of me. We can go all Pythagorean and explain how the further the distance the more apparent any shake will be.

g8ina: its a k-5 with a 100mm f2.8 macro WR lens. My understanding is it's the exact same stabilisation system on the entry level k-30.

[Bobster]

i have to say its been a while since i did any long lens stuff in low light

400mm x 1.6 = 640 - so should have had a SS of 1/640?

ISO3200 1/50 hand held - no IS


800mm x 1.6 = 1280 - so should have had a SS of 1/2000?

ISO400 1/80 hand held - no IS

with practice, getting a steady shot of a non moving subject with the 100mm macro at 1/25 shouldn't be a problem without OS

[kalniel]

You can of course improve with practise, but there's a physical limit which anyone who does target shooting or archery will know about caused by muscle tremor (at any given position your muscles are balancing against each other and constantly firing off individual contractions - the minimum tremor step size is governed by the size of individual muscle cells). It's a really easily measurable effect and you can see the individual steps on monitoring equipment. It's the reason you have to very carefully chose bow weight for archery - heavy limbs shoot faster and therefore flatter, but you need bigger muscles to use them so your muscle tremor step size is larger (when you get bigger muscles you don't create more cells, the same number just get bigger).

Personally, I find IS very useful for tele shots, but didn't realise it until I borrowed a camera/lens that didn't have it.

[TheAnimus]

I think it depends on what you mean by need, and what you mean by you.

At the end of the day, many people might feel they need only to be able to hold 1.5 times focal, and that does everything they want. But if people want lower sensitivity, or longer shutter for effect, the point is that IS really does make the difference between possible and not.

Given that it costs practically nothing to build into a sensor, I think its definitely something worth talking about, as is the limitation of the effect of such stabilisation when you have longer and longer focal lengths.