petrochemist

That's the wonderful thing about polarisers anything they can reduce they can also enhance just by twisting them round. For some reason this option is often missed out!

The only way to get rid of the polarizing effect of a VND is to take it away. It's not much good for getting the effect you want, unless you set it to the minimum darkness then unscrew the filter ...

There's no point stacking a CPL with a variable ND (which are made using two polarisers) but the combination with standard ND filters can work well.

1/2s certainly works quite well for that fountain, taken at f/10 I suspect the filter wasn't very dark, but that does depend somewhat on the light... For some shots I'll go to the maximum my camera ...

If that is all you ever shoot with you won't need a good tripod, a moderate one will be sufficient. I would expect my budget Zomei CF travel tripod to be good enough, having used it for a lens ...

Sensor muck shows much clearer at narrow apertures (when the spots are smaller but more contrasty) . I usually don't notice mine when the lens is near wide open.

Instead of a Government handout I have just been given a pay rise backdated to January. It will be quite tempting to spend the extra on one of these, but fuel & other costs are climbing at a ...

I believe both my BPM bellows were the around same price as my Helios ones (~£20), and have the added advantage of a wide range of interchangeable lens mounts being available for them (just about...

It depends on what finish has been used. Modern items can have a dye added during anodising and I suspect normal paint stripping materials wont be very effective on these. Soaking in Xylene, ...

The bulge at the bottom of the current model has proved a pain on occasion so the new version has something to offer me even if the focus speed, weight limit etc are unchanged. I'll look forward ...

Photographic printing is used in the manufacture of computer chips with the right set-up it will certainly be able to give the resolution you'd need. Any B&W film negative can be viewed via a ...

For those that don't have a 3D printer, the same lens can be fitted to your camera using bellows & readily available adapters.

I'd think that means you're insisting on not using adapted lenses. Both bodies & lenses are only 'officially sealed' when connected to the other half of the same sealed line. The weather proofing ...

It varies widely. Some mounts are always focus by wire (such as the Minolta Vectis range) There is no way to adjust the focus of these if the lens is not powered (unless the adapter allows the ...

I'm not talking of the screw thread (which is 1" diameter & protrudes from the flange) Quite a few c-mount adaptors are recessed (effectively negative lens base to camera body) This is the case in ...

Most telescopes allow the eyepiece to be changed & this changes the focal length of the system. You can fit a very high powered eyepiece to any scope, but if the scope is not wide enough such an ...

How wide is the base of your lens? All mt c-mounts are relatively small, but I've often heard of issues like yours.

That seems to work reasonably :)

Most polarisers transmit NIR but there are some expensive models made that polariser IR too. I've used a spectrometer to test transmission of a variable ND filter (which is 2 polarisers in series) ...

Probably at least $6000, yes. I hadn't seen one for sale for a while & couldn't be bothered to look. I should have said 'much more than' rather than 'at least' :)