Re: pinhole

Marek,

Ok, thanks for the info.

Regards
Yves

----- Original Message -----
From: "Marek Matusz" <marekmatusz@hotmail.com>
To: <alt-photo-process-l@usask.ca>
Sent: Tuesday, April 18, 2006 9:55 AM
Subject: RE: pinhole

> Yves,
> If you are doing a physics experiment it would matter. If you are looking
> for a pinhole as means of artistic expression, it would not make any
> difference. I stuck all sort of filters on my pinholes. They all worked.
> Marek
>
> >From: Yves Gauvreau <gauvreau-yves@sympatico.ca>
> >Reply-To: alt-photo-process-l@usask.ca
> >To: alt-photo-process-l@usask.ca
> >Subject: pinhole
> >Date: Tue, 18 Apr 2006 08:25:14 -0400
> >
> >Hi,
> >
> >hopefully this subject can be considered here but if not I'll stop
pursuing
> >it immediately.
> >
> >There are few ways to compute the size of the pinhole one needs for a
> >specific focal length and vice-versa but in most variant the wavelength
is
> >used in the calculations and most of the time a value of 550 nm (0.00055)
> >is
> >used in conditions of normal daylight. My question is this, if we use say
a
> >red filter would you suggest we use an higher value of wavelength? Any
> >suggestions for a Wratten #25 or #29 or better yet a mean to figure it
out
> >for any filter?
> >
> >Thanks
> >Yves
> >
>
>
Received on Tue Apr 18 08:47:12 2006