28th July 2005, 12:19 PM
Is one point increase in density equals one stop overexposed?
When printing from colour negatives, there are four adjustments values printed at the back of every print, the last one representing density. Is one point increase in density equals to underexposing for one stop, meaning the picture is overexposed by one stop?
I have a picture that has density = +4. How do I do the adjustment in photoshop to get a picture as if no adjustments had been done, so that I could see how the original picture is?
Thanks for replying
28th July 2005, 11:57 PM
If my memory serves me right, the density number is actually a log number.
The equivalent log 0.3 is equal to 1 F-stop.
In your case a +4 adjustment probably means positive 4 x 0.1 steps assuming the exposure is being adjusted in steps of log 0.1 density. So in effect 0.4/0.3 = 1.33 i.e. the printer has added 1.3 stops increase in exposure.
However I don't know where or how in Photoshop you can crank the exposure back precisely by density units or F-stops.
29th July 2005, 03:01 PM
Fastshot is right, you can't do that in photoshop. Film has finer adjustment tha Digital. while you overexpose in film to get more details, you do the opposite in digital. Once you get a burn out, you cannot correct the exposure to get anything back.
30th July 2005, 01:57 PM
Originally Posted by tommon
Not talking about burnout. What if its only a couple of stops over or under?