Re: Flash and IR filters and Konica 750

[Clive Warren <Clive.Warren@xxxxxxxxxxxxx>]

At 3:28 pm +0000 3/2/98, Willem-Jan Markerink wrote:

>On  3 Feb 98 at 13:42, Clive Warren wrote:
>
>> Further to my flash filter experiments using Konica 750 with no filter in
>> the dark.
>>
>>
>> Well after having a closer look at an article by Andrew Davidhazy :
>>
>> http://www2.ari.net/glsmyth/articles/filter.htm
>>
>>
>> it seems that two sheets of unexposed, processed Ektachrome produce a sharp
>> cutoff starting at 750 and finishing at 800 nanometres.  This may explain
>> the lack of any image on my Konica 750 film.
>
>How long did you expose?
>Konica will work up to #87 (not #87C), and that is quite a bit darker
>than the processed-E6 solution AFAIK [0% @ 740nm, 50% @ 795nm]....
>You just have to adjust your exposure times....you might end up with
>fractions of ASA, but noone said this would be an easy hobby....;-))


Uhhhh....  it was a flash exposure Willem-Jan and it was dark.  To satisfy
your curiosity I used 1/125 on a leaf shutter.

Take your point about requiring more light though.

The flash was on auto, but close enough to rate at 50ASA - no filter on lens.

What is required now is someone else to waste a frame or two - I'm running
out of money ;-)  Have beautiful darkslide Ektachrome shots for anyone
willing to take part in this flash extravaganza......




All the best,

              Clive   http://clive.bel-epa.com


*
****
*******
******************************************************
*  To remove yourself from this list, send:          *
*         UNSUBSCRIBE INFRARED                       *
*       to                                           *
*         MAJORDOMO@xxxxx                            *
*----------------------------------------------------*
*   For the IR-FAQ, IR-Gallery and heaps of links:   *
*  http://www.a1.nl/phomepag/markerink/mainpage.htm  *
******************************************************

------------------------------