Why are my photos noisy - discussion

did you see my image exif data ? just cross out 800 if it is correct.

Exif data by itself means very little to me because it is so easy to fake. The fact that exif data can be easily faked is common knowledge.

It would take me, or anyone else who knows what they are doing, no more than a couple of minutes to download any images you or anyone has posted online and alter the exif to make it appear I own the image.

Who knows where any exif data came from in any images you upload online.

Game set match. lead by example 😁😁

The image doesn't prove anything.

Your exif data might not be real as described earlier. Anyone can change the exif data in that image to whatever they like.

For you to suggest exif data by itself proves anything just proves how naive you are on all thing related to photography.

In any case I don't need a light meter to set exposure* as described earlier.

* exposure - amount of light that struck the sensor per unit area while the shutter was open
** optimal exposure - the maximum exposure* within dof and motion blur requirements without clipping important highlights.
*** under exposed - more exposure* could have been added with the DOF and blur constraints still being met without clipping important highlights.

I posted and highlighted the iso value not for its value ,but because Bob has added iso in the exif data to show what the camera exposure was set too 🤣🤣🤣
thats gold . commonsense always wins. Didn't i mention that a while ago in another post 🙄

Post a link to where he did that.

ISO is not part of the exposure as the Sony article I linked to said.

its under the image i posted. i even took a screen grab with the red circle 🙄

You said Bob added iso to the exif data.

Post a link to the post in which he did that and where the 800 value came from.

this is a screen grab, do you not see exif data in everyone's image that they post ?

That is not a link to where you said Bob added ISO to the exif data and it doesn't show where the 800 you circled came from. So you haven't proven anything.

You said

Post a link to where he did that.

If the link existed you would have no problem posting the link in a post.

ISO is not part of the exposure as the Sony article I linked to said.

[/quote]
Let's see if at my 68 years I understand this. Signal is overall data. Noise is bad data. SNR is an indicator of how much bad data in overall data or how much good data in overall data.
[/quote]

One useful way to look at this is noise describes the uncertainty for the data. The purpose of data is to provide estimates for the parameters we need to know. These parameters are used to compute a rendered image.

When exposure is optimized the uncertainty is minimized. The parameters used to compute the image are as close as possible to the true (but unknown) parameters. When exposure happens to be pointlessly low, then the increase in parameter estimate uncertainties result in a image with less information content.

yes, I think that pretty much explains the nuts and bolts of noise, at least in laymans terms, and I can get my head around that as you explained it.

I still think my "good data" to "bad data" analogy for SNR, is still the simplest for me even though it's not entirely accurate as Iliah Borg explained earlier.

If by "good data" you mean correct bits, then they could be a tiny minority; and you would not even know which they are. Then "all data" would be bad. In a nutshell, good/bad data makes no sense in this context.

With all my photography I try to keep to the KISS Principle as much as possible. I don't need to know exactly what is going on "under the hood" in great detail.

To help my ageing brain cope with the concept of SNR I think of it as

Signal = "good data"
Noise = "bad data"

but that's just the way I choose to think of it even though it is not technically correct.

How I think of SNR does not alter the fact that the larger the exposure*, the larger will be the SNR and the larger the SNR the less visible will be the noise. That is why I always aim to maximise the exposure* within my artistic requirements and without clipping important highlights.

* exposure - amount of light that struck the sensor per unit area while the shutter was open
** optimal exposure - the maximum exposure* within dof and motion blur requirements without clipping important highlights.
*** under exposed - more exposure* could have been added with the DOF and blur constraints still being met without clipping important highlights.

those images are in this thread ( shake head)
the exif data has been stripped from my image.
heres a link with the data not stripped
data

The "KISS principle" is about how to design systems, not how to misinterpret them.

What are you waffling on about?

That link points to a post in the Nature and Wildlife Photography forum.

can you not see the exif data ?