"hiding the bush"?

Not keen on the colour.

That's not a lens - it's a weapon of mass distruction

I hate people who can still ride their bikes

I rode mostly Ducatis for twenty five years. I was 17 when I passed my bike test and 31 when I was blackmailed into doing a car test. Never had an accident I couldn't walk away from.

One day I went to cut some flowers for Mrs Oggy, tripped carrying the knife and stabbed myself through my hand. I'm not complaining too much as had the hand not been in the way, the knife would have been in my stomach. Result - the first finger on my left hand is now a sausage. Three fingers against a Duke clutch - er, no.

Back on topic, I am now a Pentax Master. If only...

Whole sad story here.

Sorry about the picture - it's a scan of a blow-up of a 35mm taken with an O*****s trip taken 12 years ago.

...and I am a pentax master. Yeah right.

On another forum where I lurk, anyone with over 1000 posts gets the title "Needs to get out more".

Hmmm curious. I have just gone and found my old linear polariser and looked at my CPL through it. They behave just like two linears, ie there is a point at which the light coming through them is brightest, and at 90deg to that there is a point where they are virtually opaque. I had assumed a CPL was going to have a series of concentric circles, which would not explain what I have just seen.

It's thirty five years since I studdied optics (except the ones behind the bar), but IIRC, polarisation is not related to wavelength, more the planes in which the light waves oscilate.

Does anyone know how a CPL works?

I have used two linear polarisers on a film slr with some success before. They certainly vary the light getting through them, though whether or not they are strictly ND is another matter.

Remember the old polarised sunglasses which used to come with a label with a small circle of polarised plastic? You looked through the glasses at the label and rotate the label and the light level would vary. In fact with the two polarising planes at 90deg, almost no light would get through.

I am not sure exactly how CPLs work, but I don't think rotating one relative to the other would have any effect.

At this early stage in my DSLR development, I have to say that I am very fond of my Sigma 150-500, therefore If I could have only one lens then I would be tempted to have a Bigma, however, I'm with DavidTrout on the 50-135 DA*.

Hmm - the ultimate ND filter

Thanks John. I wasn't quite sure whether you meant that although one lens was of considerably higher quality than the other, it did not make any difference in this context.

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