Re: digital latitude

[TERRYAKING@xxxxxxx]

 

 

 

Karl

 

We are talking here about density. Each 'stop' is, as you say. a range of a tenth of the full scale of 3.0, ie 0.3. What you do with that density on the negative  or capture range depends upon the process you are using; it is not relevant to the question which was asked.

 

The figure of 3.0  represents the contrast range which the brain/eye optical system can perceive without moving  the eye. Of course a greater range can be percived if one adds together the range perceived when looking at a bright area and that perceived when looking at a dark area but a camera only 'sees' one point at a time.  

 

Terry

 

 

 

 

 

 

In a message dated 25/12/2004 12:28:41 GMT Standard Time, shahjen@xxxxxxxxxxxx writes:

you are talking in stops in what way?  density isn't the same thing as
stops.  a log exposure of 0.3 increase is a stop - what this translates to
on paper in density values depends on the image and the printer.  Density
on the neg can relate to stops exposure for the paper - but that depends on
the contrast grade, the enlarger head type, the sensitivity curve of the
paper and the development etc..

I can also assure you that my eye has a far greater range than ten stops!
just did a quick check and I can easily see in excess of 24 stops (my light
meter petered out at this point :-)

 

Terry King FRPS

RPS Historical Group (Chairman)

www.hands-on-pictures.com/

Moderated Discussion Group

Post message:    artaltphot@xxxxxxxxxxxxxxxxx

Subscribe:     artaltphot-subscribe@xxxxxxxxxxxxxxxxx
Unsubscribe:     artaltphot-unsubscribe@xxxxxxxxxxxxxxxxx

1. An excellent thing is as rare as it is difficult.(Spinoza)
2. A man's reach should be beyond his grasp or what's a heaven for.(Browning)
3. Frustra fit per plura quod potest fieri per pauciora.(Occam's razor or 'Keep it simple!').
4. Nullius in Verba (Horace), 'Take no man's word for it' (motto of the Royal Society).
5. If ignorance is bliss, why are not more people happy ? (anon)