View Single Post
  #91  
Old November 7th 15, 12:43 AM posted to rec.photo.digital
Floyd L. Davidson
external usenet poster
 
Posts: 5,138
Default How to measure ISO

Eric Stevens wrote:
On Fri, 06 Nov 2015 22:46:38 +0000, sid wrote:

Eric Stevens wrote:


As I have already described I have been
exposing to the left by deliberately underexposing by 1/2 stop as they
advised.

But if you are really serious/religious about avoiding clipped
highlights, you should underexpose by 2 or three stops. 1/2 a stop only
will usually leave you with lots of clipped pixels.

See https://dl.dropboxusercontent.com/u/...-7500601-2.jpg
and
https://dl.dropboxusercontent.com/u/...R--7500957.jpg

Both of these were taken hand-held with the D750 set on -1/2 EV.


Without stating what your are metering from and what type of metering your
are using neither of your posts have any real meaning. Pointing your camera
at different parts of the scene you want to photograph will indicate
different exposure values as will different metering methods for example
spot metering as opposed to centre weighted or evaluative etc.


I can't say for certain but I was probably using matrix metering.
Irrespective of the mode of metering I would have been checking both
the captured image and the histogram as I went.


I downloaded the second of the two. Not bad on a
technical basis.

There are lots of "blown highlights" in the stained
glass area, but the significance is that it doesn't
matter! Who cares if there is visible detail or not,
the whole point is to have bright colors. That is
exactly what you got!

The shot was made using center weighted metering, with
EC set to -1. And Aperture Priority, so the shutter
speed of 1/15 was set automatically.

The only complaint I would have is the use of ISO 1250
and a wide open lens that isn't that good wide open.
ISO 1600 or even as high as 3200 would have been
virtually the same, and would have allowed stopping that
lens down to a sharper aperture. That is almost knit
picking though, and is only important if you are going
to make a large print. Of course if a large print is
the objective, then it is overexposed a bit too much too,
as that lost detail would be visible in a large print.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)