Off Topic: Arecont Magic Desk

Came across this picture in an ancient Arecont customer webinar stack called forcedown.ppt.

Its a bad picture for sure*, major blur, on first look you would think somebody didn't have a steady hand, but but look at the reflection in the magic desk.

How can the desk image be so much clearer? Any thoughts?

*Limit one Arecont zinger per poster please.


Taken with an Arecont Vision camera...

I'm thinking the distance from subject is slightly further bouncing off of the table, compensating for the bad focus. Either that or Google street view got a hold of it.

Here’s my thought,

The motion blur is caused by motion of camera up and down. And since the table is on a different axis than the people in the image, the motion of the camera affects the table and the people differently in respect of motion blur. Concept could be demonstrated quite easily.

Nice work!

Question though, if it is motion blur wouldn't the subjects in the near field be affected more than the subjects in the far field?

The opposite. Imagine a long stick moving up and down on one end but staying in one place on the other end (for example camera motion blur from pivotal force ), the distance it travels up and down at the middle is lesser than at the end. So motion blur is less in the near field. This can also play a roll in the effect since the table is closer to the camera.

The opposite.

I can't really agree with that. I think that if you have two objects of the same size, that are both focused reasonably well, that the one closer to the camera will have more blurring effect if the camera is shook.

After all the closer image, just by virtue of being nearer will take up more pixels of the sensor. More pixels moving will look like more blur.

Anyway, I took some pictures of the only things close to identical in size I had around, first in focus and still and then while shaking the camera: The strings in particular have noticeably more blur in the near field than the far, no?

But in the Arecont picture we have the opposite effect, far field out focus, near in better focus, which I think would be strange if it was just the camera movement alone.

Wow! I consider the scientific phenomenon in play here way over my head. I don't often feel dumb, but trying to understand the difference between reflective/refractive focus makes my brain hurt.

The same way the dollar was clear in the comparison photo

Here's a new if unlikely theory. Camera was unsteady right when picture was clicked, but then was steadied immediately after.

Rolling shutter read out the top of the sensor with the blur, but then by the time it got to the mid-bottom the picture had stabilized.

Seems unlikely because it would require almost perfect timing.