NEX anti dust function confusion

[pvdhaar]

With all the swapping between lenses, I've found some dustbunnies on the sensor of the NEX3. Some were rather sticky and I had to remove the lens and use a blower to get rid of the specks. No problem with that, I've been doing that on DSLRs for years.

But then I wondered, doesn't the NEX have built-in anti dust shake? The specs say it has, but I'm totally confused by the manual..

The manual tells me clean the sensor as follows..
1. [Menu]>[Setup]>[CleaningMode]>[OK]
2. Confirm with [OK] (the anti dust function is automatically activated)
And here comes the weird part...
3. Take lens off
4. Blow the sensor clean
5. Turn off the camera

What's the logic of having the camera ON with the lens off? Doesn't the anti-dust shake go all by itself when the camera is switched on? Is there a way to tell when it runs, or is it that screeching sound when the camera is turned off? The screeching sound when doing [Menu]>[Setup]>[CleaningMode]>[OK] is louder/higher pitched..

 

[kxl]

And here comes the weird part...
3. Take lens off
4. Blow the sensor clean
5. Turn off the camera

What's the logic of having the camera ON with the lens off? Doesn't the anti-dust shake go all by itself when the camera is switched on? Is there a way to tell when it runs, or is it that screeching sound when the camera is turned off? The screeching sound when doing [Menu]>[Setup]>[CleaningMode]>[OK] is louder/higher pitched..

The anti-dust shakes the dust from the sensor, but where does the dust go? Right, it stays in the camera until you remove the lens and blow out the dust. Otherwise you're just moving dust around in your camera. :bang:

 

[ampguy]

I think it's just a manual way to kick in the electromagnetic discharge process. Otherwise you have no control of it, it just does it's thing when you power off.

I would use a rocket blower with the camera upside down so particles, which have mass, will fall out of the hole out of the camera.

But I wouldn't get obsessed about seeing spots at f22 or anything, if you're stopping down that far, you will have mega diffraction like a u4/3 camera at f4 or so.

 

[pvdhaar]

but where does the dust go?

Makes sense, I hadn't thought of that..

Otherwise you're just moving dust around in your camera. :bang:

Well.. that's the way my D90 works

But I wouldn't get obsessed about seeing spots at f22 or anything, if you're stopping down that far, you will have mega diffraction like a u4/3 camera at f4 or so.

Completely right.. Fortunately the NEX sensor is a tad bigger, so we can shoot without diffraction near f8

Still, I kept seeing the spots at f5.6.. So had to do something about it..

 

[shadowfox]

Right, it stays in the camera until you remove the lens and blow out the dust. Otherwise you're just moving dust around in your camera. :bang:

That's an odd design, in Olympus E-series, the dust (vibrated off the sensor using ultrasonic system) is trapped on a sticky membrane, so it won't resurface anywhere near the sensor.

Experience-wise, I never had *a single* photo that exhibit any kind of particles from any of my E-series cameras (from E-300, to E-620, to E-P2). I live in the humid climate in the summer, and windy in the winter, never took any special care when changing lenses. And I'm a manual focus guy, I use old OM lenses (and C/Y, Nikon, Konica, M42) on the E-P2, which mean, a lot of lens swapping.

Now, I know what they looked like and how annoying they can be , because I saw those in the images before we sent off my wife's Canon 5D for service and cleaning.