What kind of a filter is this?

[jun]

i recently purchased a filter lot. 1 filter has the markings on its side as:

Hoya 49mm Japan

it is around 6mm in thickness and the glass is clear but has a leather texture similar to the that found on old slr bodies. in the center of the glass around 1cm in diameter the glass is clear (no leathry texture).

anyone knows what this is or for what purpose?

i don''t have my camera with me at the moment so i can't take a picture to show you guys.
thanks

[Scheimpflug]

Sounds like a center spot diffusion filter.

You can read a bit about them (with some sample photos) here:
http://www.cs.mtu.edu/~shene/DigiCam/User-Guide/filter/filter-center-spot.html

[jun]

thank you for the reply. i tried it on my camera when i got home and there seems to be no effect on the image that i took with the filter.

my camera is a sony nex. read somewhere that these filters with the center clear glass may have no effect on dslr because the center hole entirely covers the lens itself hence the surrounding textured glass are outside of the lens? not sure about this though because i though filters work for both dslr and dlr.


i used another filter - polarizing - and when i took an image of my laptop screen there are rainbow flares only on the laptop screen. you can't take a normal picture on my laptop screen.

is this also normal ?

thank you.