Just wondering if anyone else has experienced this? If I pan my FS5 across a light coloured and well lit surface/scene (eg a bright but cloud covered sky) I get very slight imperfections in the image, almost like the Dirty Screen Effect found on some LCD TV's.

It happens with all my lenses, and thus is further back in the body. To be honest you can't see it in most none uniform shooting scenarios (which is 99% of what I'd shoot), so it hasn't really bothered me. Just wondered if it is an imperfection in my camera alone or is more common?

Are you on the latest firmware...I think it's 1.11.

Weird stuff fixed I'd latest firmware.

Yes, thanks Cliff. Something I didn't say in my original post is the imperfections are a bit like an out of focus blotch that stays in the same place in the image as you pan.

Maybe next time FS5 users are on a shoot and there's an overcast sky they could try a quick pan across it and see if they get the same.

Are you sure it's not dirt on the sensor? Because it sounds like dirt on the sensor.

If you point it to the sky and underexposue the image as much as you can then dirt on the sensor becomes better visible, I also think it's dirt on the sensor the way you describe it.

Thanks guys. You may be right. The only thing that seems unusual is the 'blotch' is longer than the more conventional out of focus specs you see on a dirty sensor.

I realise the easiest thing is if I just show you a video clip of it. I did have a good one but deleted it a while back. I'll try and get another in the next few days and post it.

Incidentally how would you go about cleaning a sensor on the FS5? I assume it sits behind the electronic ND and is inaccessible.

If...and I'm no Sony sensor expert...but if your FS5 has a dirty sensor then that would be a Sony warranty job. I think I read/heard somewhere (Alister Chapman - possibly?) that the sensor sits in a sealed unit behind the protective screen that you see when you take a lens off, and the ND system sits inside that too. I understand it is not open to the elements/air from the vents on the camera body. The fan just draws air from the ventilation grill, over a heat exchanger surface that encompasses the sensor. (I imagine the surface has fins to increase surface area).

Like I said, I'm no expert... but IF you have a dirty sensor then it must have left the factory that way in which case I'd expect Sony to rectify it ASAP and at no cost under warranty. After all, how could you have made the sensor dirty, and on such a new camera too?

As an aside, I think Canon had an issue early on with the original C300 and they modified the design (even recalling some very early serial numbers, I think) to ensure the sensor block was sealed properly and not exposed to dust ingress from the vents/fan (it's a while back but that's how I remember it).

So, let's see a demo clip and those that know a lot more than me can then tell you if that is indeed the problem with your particular FS5.

I very much doubt he has dust on the sensor itself. More likely it is on the glass in front of the sensor.
So if you let the glass in front of the sensor get dirty, how is that a warranty issue? How is that Sony's fault? You clean it yourself and move on. No matter how careful you are, it is something that needs to be done occasionally depending how frequently, where, how, etc. you change lenses. I wouldn't send a lens back to Canon when it had to be cleaned. It's normal.

That's what I meant, dirt/dust always sticks onto whatever is covering/protecting the actual sensor, so the part you see and can reach to clean. If cleaning that part doesn't help then it's time to send the camera body in and who knows, if you are lucky it might get cleaned for free.

I was assuming Nigel had already cleaned that bit of protective glass (inside where the lens mount is) and what he was talking about was dirt actually on the sensor, well behind that....As you say, the exterior glass is just something that needs to be cleaned occasionally.

Dirt directly on the sensor should be fairly sharp - not soft as described. The distance from the protective glass to the sensor makes dirt specks much softer. Of course if you put on a wide angle lens and stop it down that will make anything on the glass more noticeable. Ideally you would be able to remove most dust specks with a simple air blower bulb.