SFX has a very slight-hazy-METALIC cool neutral.
This is a very unique film type. In dr5 the normal iso is 320iso. SFX, The DMAX is low because of its infrared qualities, around 3.10 ~ 3.40-freshest/undamaged film]. Once you get the particulars of exposing this film the image quality is priceless.
It is possible to obtain some IR effects with SFX using the darkest IR filters. Exposure will depend on the scene and it is suggested you test using filtration. Use SFX as a normal film, without filtration in most cases. With filters, use the base iso and apply the filter factor.
ILFORD SFX - Ei: 125~640
NORMAL dr5 ISO: 320
