Reciprocity Effects

Reprinted from the Nikon Field Guide, Copyright 2000 Thom Hogan.

When exposure times are extremely short or long, additional exposure beyond what is indicated by the meter is necessary. In addition, color films may produce or experience color shifts. Though such shifts are generally insignificant at exposures of less than 1 minute, beyond that, try adding a CC10M or CC20M (color correcting) filter. Adjust exposure from the meter reading in the number of stops as follows:

Agfachrome RSX50NoneNoneNone+2/3+2/3+2/3+1
Agfachrome RSX100NoneNoneNone+1/2+1/2+1/2+1
Agfachrome 200 RS+1/2*+1/2*+2/3*+1*NRNRNR
Ektachrome 100+ EPPNone+1/2+1-1/3+1-1/3+1-1/2+1-1/2+1-1/2
Ektachrome E100S/SWNoneNoneNoneNoneNoneNone+1/3
Ektachrome E100VSNoneNoneNoneNoneNoneNoneNR
Fuji MS100/1000 RMS135 None at < 8 secondsUse higher ISO----
Fuji (RDP) 100NoneNoneNone+1+1+1-1/2+3
Fuji Provia (RDP II) 100NoneNoneNoneNoneNone+1/2+1/2
Fuji Provia (RDPIII) 100NoneNoneNoneNoneNone+1/2+1/2
Fuji (RF) 50NoneNone+1/3+1/2+1+1-1/2+3
Fuji Sensia (RD) 100NoneNoneNoneNoneNone+1/2+1/2
Fuji Velvia (RVP) 50NoneNone+1/3+1/2+1+1+2-1/2
Fuji Astia (RAP)NoneNoneNoneNoneNoneNone+1/3
Kodachrome 25 KM+1/2+1+1-1/3+1-1/2+2+2-1/2+3-1/2
Kodachrome 64 KRNone+1/2+1-1/2+2+2-1/2+3-1/3+4
Kodachrome 200 KL+1/2+1+1-1/2+2+2-1/2+3-1/2+4-1/2
Kodak Royal Gold (all)NoneNoneNoneNoneNRNRNR
Kodak Ektrar (all)NoneNoneNoneNoneNoneNoneNone
Kodak Gold 100/200+1NRNRNRNRNRNR
Kodak Gold 400NoneNoneNoneNoneNRNRNR
Kodak Gold 1600NoneNone+1/2+1+1+1-1/2NR

*Assumes CC25 filter for shorter exposures, CC50 for 10-second+ exposures

None = No compensation required    NR = Not recommended

Film manufacturers introduce new emulsions [less frequently than before digital]. Nevertheless, film families tend to have similar tendencies. For example, when Fujichrome Provia (RDP II) was introduced to replace Fujichrome 100 (RDP), it shared the original’s excellent reciprocity characteristics and remained one of the few films that did not require any adjustment with exposures up to 4 seconds. Thus, while some of the films listed are no longer produced, I’ve left the data for them here, as reciprocity characteristics tend to run in families.

For critical applications, Kodak doesn’t recommend exposures of 10 seconds or longer with most of their color slide films and suggests the following combination of exposure compensation and filtration for 1-second exposures:

FilmCorrection Filter
Kodachrome 25 (KM)+1/2 stopCC05R
Kodachrome 64 (KR)NRNR
Kodachrome 200 (KL)+1/2 stopCC10Y
Kodachrome 40 Type A (KPA)+1/2 stopCC05R
Ektachrome Elite II 50/100 (EA/EB)none (to 10s)
Ektachrome 64 (EPR)+1/3 stopCC05R
Ektachrome 64T Pro (EPY)nonenone
Ektachrome 100 (EPN)+1/3 stopCC05R
Ektachrome 160T (ET, EPT)+1/3 stopCC10R
Ektachrome Elite II 200 (ED)+1/3 stopCC05R
Ektachrome 200 (EPD)+1/2 stopCC05M
Ektachrome 100 Plus (EPP)*+1/3 stopCC25R
Ektachrome 100S/SW/VSnone (to 10s)none
Ektachrome 400X (EPL)** +1/3 stopCC05R
Ektachrome P1600 (EPH)+1/2 stopCC05R + CC05Y

NR = Not recommended

*Pro versions are +1/2 stop with CC05B.

**Also recommended at 10 seconds +1/2 stop with CC10R.

Most Kodak black-and-white films suggest 1 extra stop of exposure at 1 second, 2 stops at 10 seconds, and 3 stops at 100 seconds. Note that the C-41 processed T-Max T400CN has no reciprocity out to 120 seconds. You can also call Kodak at 1-800-242-2424 for advice on their films’ reciprocity characteristics.

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