CPL and 40mmLtd

OK not a problem yet - but it may well be soon

Now I love my little 40mmLtd and have got a Hoya CPL for it .

This is indeed a 30.5 filter which is screwed into the hood - can do that - a wee bit fiddly thanks to my hands but it's possible.

Now for the problem - I understood that with a CPL on you rotate the filter to get what you want - so how do you do this when the filter is screwed into the back of the hood which is then screwed onto the lens ?

Suggestions please before I drive myself daft thinking about this

Not knowing the setup I may be totally out of line here. Do you not just rotate the hood so that the movable part of the filter goes with it.

I think I might be inclined to remove the hood and fit a 49mm filter plus a standard lenshood.

John the Pentax book said to get a 30.5 and fit it behind the hood . This is what I did .

bforbes - the hood is virtually flat and screws into the lens itself . This is a pancake lens

You can fit 30.5 filters indside the hood but absolutely no use at all with a cpl, as JR says you need a 49mm. It doesn't have to be a particularly thin one, I use a Pentax one which is very deep and the supplied hood on top of that.

Fitting 30.5 filters only retain the tiny size of the lens.

Yes like the others say there is no way to turn the CPL when it's fitted inside the hood.
I use a 49mm one and screw on the hood on that and that works fine.

That means you have camera - lens - cpl filter - hood, in that order.
Which again means that if you turn the hood, you will also turn the cpl.

Terry how do you intend to turn the hood?
screwing it on and off?

It doesn't work like that, The truncated conical hood attaches to the lens by a 49mm thread, in turn the lens cap attaches to the hood by a 30.5 mm thread. I'm now just wondering if the the 30.5 filter will attach to the front of the lens hood (almost certainly) and the OP can use their filter but without the benefit of the lens hood.

Stefan,
I imagined that the filter has internal threads corresponding to the lens threads, and so the filter would turn with the hood. But I may be totally wrong, of course.

"Behind the hood" I read as between the lens and the hood.

Ken,

In that case TT would be better off with a 49 mm filter, wouldn't she?

Terry, you are quite correct but since these things are relatively expensive, I'm thinking of a way to utilise what she has.

I have to say that it is a something of a mystery to me that something as simple as a filter can cost more than a something as complex as a zoom lens (18-55 DA)

The lens hood has two threads.
One for fitting the hood onto the lens, that's 49mm and one at the opening of the lens hood that's 30,5mm
I hope that make things clear.

The DA40mm has a very strange hood.

This might explain things, the round thing in the right lower corner is the lenshood

Yes I actually think so too because quite a lot off pentax lenses use 49mm thread so it's never a waste to have one if you use Pentax.

Stefan,

Is that a 30.5mm pinch cap to replace the screw-in one that comes with the lens?

Good idea if so, the fiddly cap is about the only drawback of this lens that anyone reports.

BTW, was that picture taken due to a forthcoming sale of your DA 40mm?