I need to open up the front of my VX2000 to clean mold that is on one of the internal lens elements.

Has anyone any experience of this? It looks like the first step would be to unscrew the black ring marked "SONY VIDEO LENS / OPTICAL 12X" using the small notch in it (at 9 o'clock as you look at the lens) that seems to be provided for that purpose. After that I'm not sure and would appreciate any insights before I take the plunge.

Do not disassemble your lens. It takes special equipment to realign the lens assembly. It is almost impossible to align it by eye. Most repair facilities will charge more to work on equipment that is already apart. send your camera to Sony for repair.

Credit....alanbarker.com

Sony PD150: Dirt Behind the Front Lens Element.



One of the most nagging problems of small-format cameras is that the extreme depth of field brings dust on the lens into focus. Assiduous lens cleaning is a necessity.

When dust appears on the back side of the front element, a more drastic but easily doable procedure is possible.

(Photo1)

Around the lens is an official looking ring imprinted “SONY VIDEO LENS...” This is nothing more than a thin gasket-shaped piece of plastic held in place by rubber cement.

On the left side you will see a notch and key in this ring. Stick a pointed object into the notch and the ring will easily pry up.

(Photo2)

While gently lifting the ring, use a second pointy object such as a small jewelers screw driver in tire iron fashion to lift the ring free. Set it down butter side up to preserve the goo.

The front element is held in a rather crude plastic bayonet mount that can easily be disengaged by rotating counter clockwise with your pointy tools.

(Photo3)

When you replace the front element, make sure it clicks into place. The lens is keyed so it can be replaced in only one prientation.

Replace the official looking plastic ring.

By the way, the front element seems to have no optical function other than to collect dust and add flares. I think its sole purpose is to seal the front of the lens which it does poorly.

© Alan Barker 2003

Is Allan going to be there to help. I think it's poor advice.

Correct Lou. The front element (in the vx2k) is just a coated spherical piece of glass with no optical power and which can easely be taken off after (slowly) removing the softly glued plastic ring and and couter clockwise lose the fixation ring. The reason for the non flat front element is just for avoiding (defocussing) "fireflies" which come from the flexible prism (OIS)backscattering. The only problem could be that you have to do this under (allmost) dustfree conditions...

Thanks for the debate guys. If the mould was just on the back of the front element, I'd go for it. But it looks like it's some distance back with at least one more element between the front element and the one with the mould on it. It's almost certainly off to Sony on Monday, but in any case how many elements are there in the front assembly? Does anyone know where I can see a schematic diagram? The service manual I downloaded today has no diagrams in it, and I like to understand the construction and the problem if nothing else so I know what I'm talking about with Sony.

Would this procedure from alanbarker.com be applicable to the PDX10?

The Sony's lens has 12 elements in 9 groups. Two of these individual elements have aspherical surfaces. There are three prisims that split the light off into the RGB constituents. In front of the front element are two plane parallel sheets of glass separated by an oil. This forms the VAP Steadywshot.

tom.

And it is this oil that causes the "fireflies" when videotaping bright candles and streetlights.

<<<-- Originally posted by Tom Hardwick : The Sony's lens has 12 elements in 9 groups. Two of these individual elements have aspherical surfaces. There are three prisims that split the light off into the RGB constituents. In front of the front element are two plane parallel sheets of glass separated by an oil. This forms the VAP Steadywshot.

tom. -->>>

Is it likely that what I am seeing behind my front element is fungus? Sunlight might remove it in that case, right?

Related thread:
http://www.dvinfo.net/conf/showthread.php?s=&threadid=31913

Sony Thailand have quoted me just 30 dollars to clean the mould so I'm going for it. I'll let you all know how it goes.

Fireflies mostly find their origin in the back and forth reflections between the flat front of the VAP and the flat (poorly coated) protection filters that many people add in front of the cam optics.

Yes, that is also correct. A good coated lens such as B+W would prevent spot flaring. However, the "firefly" situation with the SONY camera looks different and is corrected by turning off the stabilzer.


<<<-- Originally posted by Andre De Clercq : Fireflies mostly find their origin in the back and forth reflections between the flat front of the VAP and the flat (poorly coated) protection filters that many people add in front of the cam optics. -->>>

Fireflies are still there if the OIS is turned off, but they don't jump that much anymore if the cam is handheld.

<<<-- Originally posted by Andre De Clercq : Fireflies mostly find their origin in the back and forth reflections between the flat front of the VAP and the flat (poorly coated) protection filters that many people add in front of the cam optics. -->>>

Unfortunately, that is not the case. The fireflies are caused internally in the lens and it occurs even if you don't have a filter on the front.

That's why I wrote "mostly" Mike. And indeed image forming reflections can come frome everywhere in an optical system. Two things however: reflections from non flat surfaces rapidly defocus and end up in general glare effects, and the "deeper"the reflection originates in an optical system, the less image creating it is. "Dancing" fireflies (most frequently seen) from candlelights, streetlights,... definitely come from the front suface of the (moving) OIS prism reflecting back onto a flat surface in front (filter). The spherically curved front element on the VX defocuses the back reflected rays and doesnt generate firelflies on itself.

$30 sounds very reasonable to me. I'll ask my local Sony rep and see what happens.

Just to keep you updated, Sony Thailand did the mould cleaning for me. I was without the camera for a couple of weeks and they charged me 963 baht (23 dollars). All seem fine and the mould is gone, although there is a very tiny speck of something left down inside the lens that doesn't seem to show up on video. Generally I'm happy and glad I didn't go the DIY route.

Thank You Nick. Very promising.