Purple Spot

[Paul Alister]

I just noticed a small purple spot on my video! I cleaned the lens and it made no difference. Looking at the lens also I could not see any purple spot. What is the cause? Is it something to do with t he chips? Hap any one else had this problem on their EX 1?

Thanks Paul

[Marcus Durham]

Originally Posted by Paul Alister

I just noticed a small purple spot on my video! I cleaned the lens and it made no difference. Looking at the lens also I could not see any purple spot. What is the cause? Is it something to do with t he chips? Hap any one else had this problem on their EX 1?

Thanks Paul

Sounds an awful lot like dust on the sensor.

[Zoran Vincic]

I experienced exact the same thing with one of the EX1R cameras I was working with few months ago, it was a big round purple blob which got worse when stopping down the aperture, probably dust on the sensor (or more likely, the prism), as Marcus said.

[Dave Morrison]

+1
My EX1 was full of crud and I never noticed it until the first time I pointed the camera toward the open sky and stopped down to around f8-f11.

[Dave Gosley]

How was this resolved please?

[Dave Morrison]

I sent it back to Sony and they cleaned it out. I think they MIGHT have replaced the lens, too.

[Annen James]

I work on a show that shoots on 3 EX1's. We shoot in very dusty conditions. We have had this happen all all 3 of our cameras. We have a few scenarios. 1- DON'T USE COMPRESSED AIR. PERIOD. We figure the week point is the ND selector switch. On one of the cameras, the purple spots, which are dust or crud, were on ND1. You can temporarily fix the dots by going to a low aperture. Otherwise it's back to Sony for a cleaning. I had one of our cameras with a purple dot go in to Sony, and they said it needed a new prism. I said fine, and asked for them to return the defective part with my fixed camera, which they did. $2200. The prism, with the 3 CCD's attached is quite an impressive unit. However, it is totally sealed, so I somehow wonder.. That particular camera was my personal one, and cared for VERY well, always. However, I did use compressed air to clean it religiously.

We have also had a camera that had no less than 6 purple dots on it in 3 shots, then the subsequent shots and all others, no dots....

It seems to be a very common problem, and one that Sony is aware of. I still love the camera, and think there is no equal in that class. Just have to be very careful, always bag it if you expect ANY dust, use a photo-style bulb hand blower to clean, and tape when possible the ND filter selector. My 2 cents, having sent back all 3 EX1's to Sony, in one season of shooting.

[Alister Chapman]

The filter selector does appear to be where dust can get in. Tape over it in dusty conditions is a good tip.

I too agree that you should never use canned air or compressed air. It is too fierce and will force dust into the camera. A small soft paint brush is a great way to remove dust from all the little nooks and crannies on a camera.

[Bruce Rawlings]

I had what looked like a purple 'hair in the gate' on my EX1. Sony replaced the whole block without a quibble.

[Mark OConnell]

The dread purple spot. Yikes...

I've been down that road and it was a real drag. Couple of points:

If it is in fact dust on the sensor it has nothing to do with how you clean the camera, compressed air, bulb, or brush; and has nothing to do with the conditions that you shoot in, i.e. very dusty or whatever. This is because the prism block is sealed. Nothing can get in or out. That's why the entire block has to be replaced. It cannot be cleaned. So if nothing can get in or out how did the dust get there? Must've been in manufacture I suppose.

This is a very expensive repair and it seems to be a fairly common problem. This makes the purchase of a good extended warranty for the EX1 advisable.

[Brent Kaplan]

I have a ex3 that has this issue but it seems to come and go , I dont know what to do about it, any Ideas
I have no warranty my camera is used.
Help

[Alister Chapman]

While the prism assembly itself is a sealed unit, dust can still get in and on to the ND filters, the rear of the IR filter and the prism block window. So, using canned air is still not a good idea. Canned air is also very good at forcing dust into the lens assembly where it can get onto the glass elements or into the zoom, focus and iris mechanisms. The grease in these mechanisms can then trap the dirt and become sticky or erratic and you may experience increased wear as the dust acts as an abrasive. IMHO canned air should never go anywhere near a delicate instrument like a video camera. As well as the force of the "air" blowing dirt into the camera the gas used can in some cases leave an undesirable residue on coated optics and glass elements.

Canned air is the lazy way to clean a camera, all it does is blow the dirt around. Much better to get a camel hair brush to remove the dust from sensors and optics, combined with a good quality lens cloth.

I regularly shoot in desert sandstorms, hurricanes, tornadoes and all kinds on nasty weather and atmospheric conditions. In over 20 years of doing this I have never had serious issues with dirt inside my cameras, while the guys that use canned air have no end of problems.

[Tom Hardwick]

I agree with Alister - there's lots of entry points for air to get into a video camera. The very act of zooming the lens 'breathes in and out' air, along with all the airborne dust. Some stays behind and finely coats the individual elements, effectively slowing the lens.

It's often a surprise to people to see how much dust is inside what appears to be a superficially clean lens. Use a video light to illuminate a zoom's front element, holding the lamp perpendicular to the lens' axis. The older the lens is, the better this experiment brings forth the gasps.

tom.

[Mark OConnell]

I agree with Alister and Tom's concerns about blowing dust into the camera, but that is a separate issue which, though serious, really has nothing to do with the dread "Purple Spot". No amount of compressed air could create this problem. Though the posts are instructive and sound, they are, strictly speaking, off topic and potentially misleading.

[Dave Gosley]

I'm off to the shops to buy a camel hair brush. I have never used compressed air on my camera although I will admit to having thought it might be good / might be bad - thus wasn't sure - hence never did.

I will admit to having used a vacuum cleaner with small hand held brush on it to clean my gear - including camera in the past... It's not a particularly strong one.

I always have a moan at my missus for using dusters and brushes - flicking dust around and making more air-born than when she started!

Almost every shoot, I use a soft lint free cloth and lens cleaning fluid from B&H and ensure the glass is clean and the camera nearly always comes out of the case dust free...

I've learned some good stuff on this thread, thank you..