Close Examination of Fuji X-Series Lag Time

Easycass wrote:

georgehudetz wrote:

I using a 56 on an X-Pro1, I have verified that the time required to complete a shot, when stepped down and in manual focus mode, does vary depending on the direction of the most recent focus adjustment. It clearly takes longer to get control of the camera back when immediately prior focus change increased the focus distance (I have not tried it with the focus direction flipped). You can even hear an "extra" sound at the end of the exposure process when your last focus adjustment increased the focus distance that is not present when the most recent adjustment decreased the focus distance.

However, as best I can tell, this happens after the shutter has open and then closed. Which is to say, it shouldn't affect the actual lag in terms of getting the shot. Of course, it does affect how much time it takes to get control of the camera again, and the screen blanks a little longer, so I absolutely agree that it is undesirable. However, as best I can tell it does not affect the amount of time required between pressing the shutter button and capturing the image.

But I'm just doing a quick test. Does your test data bore this out, one way or another?

Hi there,

Thank you for also doing teh testing. Observation 9 of my test report originally tried to describe the sound I am hearing from the lens. Here is an updated version with links to videos of the two states, where the shutter response is faster at 200ms, and when slower at around 500ms: -

1. When a lens has been had its focus adjusted, at a stopped down aperture, when the shutter-release button is half pressed, as the aperture blades are moved to the stopped-down position, the characteristics of the audible sound sourced from within the lens changes. This is best described as follows: 1) when the lag is within the 200ms range (normal), the sound is a definitive short 'click' at shutter-half press, and a longer click-motor sound when the shutter is unpressed (see video here: https://www.youtube.com/watch?v=TA5Rq5Muk7g). 2) When the lag is within the 300-500ms range (longer lag than normal), the sound sequence is reversed, with a longer click-motor sound at shutter-half press, and a definitive short 'click' sound when the shutter is unpressed (video here: https://www.youtube.com/watch?v=uKxZDXXL5O8).

So, in the first case, I actually find the black out period is longer after the shutter is fired, but in the second case, where the shutter lag before the shot is longer, the black-out period is shorter afterwards. There is something happening in the lens, not directly tied to the aperture blades themselves, but linked to the focusing motors I believe (which is why a half turn of teh lens focus either way has some influence on things, even though I do not know 'why' it is like that). In the faster case, the 200ms response time, the extra motor movement occurs after the shot, and in the second case, the 500ms response time, the extra motor sound happens before the shutetr is fired.

This explains what I am seeing...

If you listen carfully on half press, and on unperss, in both the short lag and long lag case, maybe you can hear the same?

Cheers,

Cass.

Yes, I see (or hear) it too.  I've taken to testing using the "back button" focus method, and, sometimes, the extra lag is before the shutter activation, and sometimes it's after.  However, it seems rare (never?) that I experience a 500 ms lag.  But that's just a guess, since I'm not actually measuring anything.

Very odd, to be sure.