What a great resource for those stateside.
I was looking for a couple of B&W monochrome contrast control filters in 52mm to match larger sizes in the same spec that I already have. Between all the ‘too good to be true’ online discounted prices, and the impossibility of finding a yellow or a red filter in a modern camera store that only sells digital cameras and UV filters, I was finding it surprisingly tricky. Eventually I discovered that Calumet in Germany- somewhere accessible to me, currently have discounted prices on new B&W filters including contrast control ones. I can only assume that Calumet in Germany is about as safe a bet as there is for authentic B&W filters, but I suppose the proof will be in the negative as they say! Not cheap, but I like the quality.