On Jun 15, 2018, Jim-P wrote
(in article ):
On Thu, 14 Jun 2018 19:47:36 -0700, Savageduck wrote:
On Jun 14, 2018, Ken Hart wrote
(in article ):
On 06/14/2018 08:05 PM, Savageduck wrote:
On Jun 14, 2018, Jim-P wrote
(in article ):
On Thu, 14 Jun 2018 14:26:40 -0400, PeterN wrote:
On 6/14/2018 1:48 PM, Jim-P wrote:
In film cameras, ISO referrs to the sensitivity to light of the
emulsion.
Manufacturers formulate different film emulsions with different
sensitivites tarding increased grain with increased ISO speed.
In a digital camera, presumably the sensor does not adjust itself to
have
greater sensitivity. Or does it?
So what is happening in a digital camera when I choose a greater ISO
setting? Is more amplification being used?
I tried to understand this page but it got far too technical....
https://photography.tutsplus.com/art...echnical-explo
ration--photo-11963
I am going to try to give you a simplified, non-technical explanation.
As with most generalities it is not 100% technically accurate, but
should serve as a guideline.
ISO is a measurement of the light sensitivity of the sensor. Digital ISO
is adjustable in many cameras. And yes, it is a matter of adjusting the
amplification. If you are using a wider lens opening, and slower shutter
speed, you will be able to use a lower ISO.
Digital noise is one of the undesired artifacts in the image. Higher ISO
will result in more digital noise, and lessor image quality. Many of the
newer high quality sensors are designed to work at a higher ISO, with
less noticeable noise, and reduction in image quality.
There are some of us here who do not object to noise, while others have
serious objections. The point at which noise becomes objectionable often
comes down to a matter of taste and personal preferences.
Thanks. This makes me wonder what ISO I should set, if I don't leave it
on
auto.
In the film days, we used the "Sunny-16" rule: Set the shutter speed
equal to the ISO (then "ASA"). In bright sunshine, use f/16. Slightly
cloudy- use f/11, open shade- f/8, full shade- f/5.6. This technique
would usually give a good exposure.
Combine that with the "focal length equals shutter speed" rule: The
longer the focal length, the faster the shutter speed to give acceptable
hand-held images. For a 200mm lens, you use a shutter speed of 1/250
second.
Example: 100mm lens calls for 1/100 second minimum. Set the ISO also at
100, and use the "Sunny-16" rule. Then refer to SD's exposure triangle,
three paragraphs down...
Let us start by asking, what camera are you using?
It would still be good to know what camera the OP is using.
I am using a smartphone camera. Although it is not as high quality as a
DSLR the principles should be the same and I am interested in understanding
them before taking my photography further.
The smartphone model is a Moto G5 Plus with a Sony IMX362 Exmor RS camera
module which is also used in the Nokia 7 and Samsung S7 Edge
https://phoneproscons.com/794/moto-g...camera-same-am
azing-sensor-as-in-xplay-6-and-zenfone-3-zoom/
There is nothing wrong in using a smartphone camera. However, you are going
to have limitations which you will not find in modern DSLR, or mirrorless
digital cameras (MILC). Even with third party photo apps for your smartphone
you are going to have limitations of physical sensor size, and adjustability
of the exposure triangle.
The next question is; are you intending to add a modern digital camera to
your current photography kit?
I recall that old Sunny 16 rule and the thing which strikes me most about
it now is how slow the shutter speeds were in the old days. 1/250 was one
of the faster speeds I would use for day to day photography years ago but
my current smartphone often uses speeds of 1/1000 or 1/2000 which is
fantastic because by hand steadiness is not what it used to be.
True. However, that was in the days of 25 ASA film. Things have changed,
along with high ISO performance with fast lenses, there are other technical
improvements with things such as various types of image stabilization with
stabilized lenses (VR, IS, OIS), and in camera image stabilization (IBIS).
--
Regards,
Savageduck