Re: Flash and IR filters and Konica 750

[Clive Warren <Clive.Warren@xxxxxxxxxxxxx>]

At 2:22 pm -0800 3/2/98, Joshua_Putnam wrote:

>>According to Konica's technical bulletin No. Tech 015 "Konica Infra-Red 750
>>has a sensitivity range from 640 to 820 nm in addition to the intrinsic
>>sensitivity range of AgBr 400- 500nm. The peak sensitivity is 750 nm hence
>>it's name".
>
>>So the answer seems to be - use HIE :-)   Which is a shame as I was using
>>120 konica film on a rangefinder 6 x 7.  Guess I'm going to have to roll my
>>own panoramic flash shots....
>
>Haven't tried it yet in my 6x9 rangefinder, but I shot a roll of
>Konica 750 in my OM-4 this weekend, having only used HIE before,
>and got good exposures using my T-32 flash on manual with an 87
>filter.
>
>I bracketed through a relatively wide range (five stops) and
>haven't yet decided which shot looks like the best exposure so I
>can figure out a guide number for the filtered flash.  Exposures
>range from almost black negatives to almost clear -- definitely
>a narrower range/higher contrast than HIE.  But it does work.


That's great, now try it with two sheets of unexposed, processed Ektachrome
over the flash head, and no filter on the camera in the dark.

It would be good to use a flash gun in the dark or at low light levels
using Konica 750 without blinding people with the flash.

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  *
******************************************************

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