p.3 #1 · Why is it recommended to turn off IBIS on Sony cameras when using a tripod?
The concept gets more complicated with the very high performing ibis. As mentioned above the earth’s movement sets a limit of 6.3 stops. But Canon, Olympus, and now Sony on the Rv claim more than this. I’m also not sure what kind of performance a tripod achieves in reality (I know it depends on the tripod). I can imagine tripods with big lenses in the wind would still benefit from ibis. A good tripod in the calm could exceed even the best ibis. Then you have Astro, the high end ibis defaults to terrestrial stability, but I could envision a firmware switch to enable Astro, or true inertial stability. Haven’t googled it yet, but I wonder how high end ibis performance is on the space station?
For myself when I had the Sigma 100-400 I turned stabilization off. All other lenses I leave it on. I did test for a difference and found none. But I also don’t shoot stuff that would matter. No long exposure landscape and the Astro I do is stacked to avoid star movement in the frame.
p.3 #2 · Why is it recommended to turn off IBIS on Sony cameras when using a tripod?
Can you explain what you mean by the earth sets a limit of 6.3 stops? I was actually going to start a new thread about this, but since you brought it up…
I’m not understanding how stabilization can be measured by how much light hits your lens.
p.3 #3 · Why is it recommended to turn off IBIS on Sony cameras when using a tripod?
Tarekith wrote:
Can you explain what you mean by the earth sets a limit of 6.3 stops? I was actually going to start a new thread about this, but since you brought it up…
I’m not understanding how stabilization can be measured by how much light hits your lens.
It’s just a mathematical term related to exponents in a base 2 system. So if you have 3 stops of ibis this will reduce vibration by a factor of 2^3 or 1/8 as much vibration. How this relates to photography and why we might want to talk about it in stops is 3 stops of ibis should allow you to reduce shutter speed by 3 stops and still achieve the same motion blur.
The reality may be a bit more complicated in that vibration that caused motion blur is frequency dependent. You can have slow movement in a constant direction or medium oscillation caused by hand shake or faster vibration form other mechanical sources. The ibis is typically given a single rating of say 5.5 stops, but it won’t achieve this for all different frequency vibrations.
p.3 #5 · Why is it recommended to turn off IBIS on Sony cameras when using a tripod?
Tarekith wrote:
Thank you for breaking it down for me!
Is stops in relationship to shutter speed also exponential? IE, does going from ss800 to ss200 net you 3 or 4 stops of additional light?
I’d love to find more resources that go into greater depth on this stuff, hard to find much beyond basic intro photography tutorials.
Stops in shutter speed, aperture, or ISO are all exponential. So if you go from ss800 to ss200 that is 4x more light or 2^2, 2 stops more light. So you could change aperture by 2 stops and get the same exposure, say go from f/4 to f/8. Or you could keep the aperture the same but change ISO by 2 stops going from ISO 400 to ISO 100.
