How high can I take shutter angle before extra motion blur?

[Roger Alexander]

Sometimes when my scene is too dark and I want to brighten it up without raising the ISO (and without adding more light) I will slightly raise the shutter angle from 180 degrees to like 225. Conceptually, I know that 180 is like the standard and doubles your frame rate. When you lower the shutter angle, the shutter speed is faster for that choppy look, and if you raise the shutter angle it slows the shutter speed and adds more motion blur into your shot. (Hopefully I don't have this backwards lol) My question is, how high (slow) can I move my shutter angle above 180 before I start to notice extra motion blur in the image? My goal here is to raise the shutter angle as much as possible to brighten my scene more without a noticing the extra motion blur. I plan to run some camera tests myself but I was curious if there some sort of formula or pre-completed tests on this?

[Jay Young]

Why do you not want to add more light?

[Stuart Brereton]

It depends on your scene. If there is no fast movement, a wider shutter angle can be unnoticeable.

[David Mullen ASC]

Obviously any increase in shutter time will increase motion blur, so how much you notice that depends on how much motion is in the shot and how sensitive you are to such a change -- there isn't some crossover number where it becomes noticeable, it just gets gradually more obvious the more you increase the shutter time depending on the amount of motion in the frame. If it is a static shot, no motion in the frame, you could shoot with a 360 degree shutter angle and no one would be able to tell.

 

You just have to judge your scene and how much movement there is in it, both subject-wise and camera-wise.

[Robin R Probyn]

Why do you not want to add more light?

 

 

Apart from just plain not having enough lights .. there are some locations that wont allow any lights at all.. Ive had Art galleries.. Museums .. some hospitals..alot of labs.. ... its alot better in the LED days now.. but their rule books haven't always been up dated..