Looking for some help

[Kier]

Hello, I will apologise in advance, I am new to the world of “online forums” so please bare with me.
I was hoping someone would be able to offer some help, I took a photo earlier, and after export to my iPad, if I turn the screen brightness up, I can see some ’patches’. The best way to describe would be as if it is pixelating but just in some parts? You may need to also turn up you brightness/zoom in to see what I am referring too. It is primarily in the dark parts of the image? Thank you everyone who takes the time to look

 

[Ysarex]

Welcome to the forum -- glad you're here.

I downloaded your photo and had a look. The patches you're seeing are the result of JPEG compression. If you zoom in real close and look at the edges of the patches you'll see a pattern of squares. Those squares are the 8x8 pixel JPEG compression grid.

The JPEG algorithm was working down at the low (dark) end of your photo and there was very little data there. So JPEG basically did it's thing and truncated the shadows of your image off to just a few tones.

I had the photo's histogram display in the screen shot below. Your photo's histogram is shall we say "not right" and suggests you may be responsible for those patches. Your histogram ends in a nice straight line before reaching the far left side of the graph. This does not happen naturally. Did you use the Curves adjustment in LR?

 

[Kier]

Welcome to the forum -- glad you're here.

I downloaded your photo and had a look. The patches you're seeing are the result of JPEG compression. If you zoom in real close and look at the edges of the patches you'll see a pattern of squares. Those squares are the 8x8 pixel JPEG compression grid.

The JPEG algorithm was working down at the low (dark) end of your photo and there was very little data there. So JPEG basically did it's thing and truncated the shadows of your image off to just a few tones.

I had the photo's histogram display in the screen shot below. Your photo's histogram is shall we say "not right" and suggests you may be responsible for those patches. Your histogram ends in a nice straight line before reaching the far left side of the graph. This does not happen naturally. Did you use the Curves adjustment in LR?

View attachment 203589

Thank you so much for not only taking the time to look over the image and get back to my, but for also being able to hit the nail firmly on the head! What you are saying makes complete sense. Yes I did use the Curves tool on Lightroom, although, perhaps on reflection, didn’t use it very well! so, again, I will apologise as I am new to the forum world, however, would I be pushing my luck to ask if you have any tips to prevent this from happening, whilst still maintaining the dark moody feel to the photo ?

 

[Space Face]

Welcome.

 

[Ysarex]

Welcome to the forum -- glad you're here.

I downloaded your photo and had a look. The patches you're seeing are the result of JPEG compression. If you zoom in real close and look at the edges of the patches you'll see a pattern of squares. Those squares are the 8x8 pixel JPEG compression grid.

The JPEG algorithm was working down at the low (dark) end of your photo and there was very little data there. So JPEG basically did it's thing and truncated the shadows of your image off to just a few tones.

I had the photo's histogram display in the screen shot below. Your photo's histogram is shall we say "not right" and suggests you may be responsible for those patches. Your histogram ends in a nice straight line before reaching the far left side of the graph. This does not happen naturally. Did you use the Curves adjustment in LR?

View attachment 203589

Thank you so much for not only taking the time to look over the image and get back to my, but for also being able to hit the nail firmly on the head! What you are saying makes complete sense. Yes I did use the Curves tool on Lightroom, although, perhaps on reflection, didn’t use it very well! so, again, I will apologise as I am new to the forum world, however, would I be pushing my luck to ask if you have any tips to prevent this from happening, whilst still maintaining the dark moody feel to the photo ?

Nothing for you to apologize for -- you came to a good place for help. We all need to do that in our turn.

So now that you've answered my question, I assume you used Curves in LR to apply what is often referred to as a matte black look to the photo. In Curves you grabbed the bottom left corner (black) node and pushed it up. That truncated your blacks in the photo removing what little natural gradation was there so that when the JPEG algorithm went to work on the image it found large areas of nearly the same tone which it then forced into large patches of just a few separate tones.

I also saw (reported in the EXIF data) that you had to apply a substantial increase of a stop and 2/3 to the exposure for the photo which suggests your original NEF file could have benefitted from more exposure. That means you had less to work with from the start down at the bottom in those blacks.

So if you get a chance to re-shoot it consider more exposure. If you want to try and re-process it use the Blacks and Shadows sliders in LR to make sure the photo reaches black without that chop from the Curves control.

 

[John Fantastic]

nice! Thank you Ysarex I learned something new today. You must be working for the digital forensic division of the FBI?

 

[Kier]

Welcome to the forum -- glad you're here.

I downloaded your photo and had a look. The patches you're seeing are the result of JPEG compression. If you zoom in real close and look at the edges of the patches you'll see a pattern of squares. Those squares are the 8x8 pixel JPEG compression grid.

The JPEG algorithm was working down at the low (dark) end of your photo and there was very little data there. So JPEG basically did it's thing and truncated the shadows of your image off to just a few tones.

I had the photo's histogram display in the screen shot below. Your photo's histogram is shall we say "not right" and suggests you may be responsible for those patches. Your histogram ends in a nice straight line before reaching the far left side of the graph. This does not happen naturally. Did you use the Curves adjustment in LR?

View attachment 203589

Thank you so much for not only taking the time to look over the image and get back to my, but for also being able to hit the nail firmly on the head! What you are saying makes complete sense. Yes I did use the Curves tool on Lightroom, although, perhaps on reflection, didn’t use it very well! so, again, I will apologise as I am new to the forum world, however, would I be pushing my luck to ask if you have any tips to prevent this from happening, whilst still maintaining the dark moody feel to the photo ?

Nothing for you to apologize for -- you came to a good place for help. We all need to do that in our turn.

So now that you've answered my question, I assume you used Curves in LR to apply what is often referred to as a matte black look to the photo. In Curves you grabbed the bottom left corner (black) node and pushed it up. That truncated your blacks in the photo removing what little natural gradation was there so that when the JPEG algorithm went to work on the image it found large areas of nearly the same tone which it then forced into large patches of just a few separate tones.

I also saw (reported in the EXIF data) that you had to apply a substantial increase of a stop and 2/3 to the exposure for the photo which suggests your original NEF file could have benefitted from more exposure. That means you had less to work with from the start down at the bottom in those blacks.

So if you get a chance to re-shoot it consider more exposure. If you want to try and re-process it use the Blacks and Shadows sliders in LR to make sure the photo reaches black without that chop from the Curves control.

Without sounding like a broken record, I need to thank you again! And I have to agree with John above, either you work for the FBI, or there is some kind of sorcery involved, because I did indeed grab that bottom left corner and lift it! So I ended up re-processing with your tips in mind, and it has solved my issue! I am so pleased I found this site, I think it’s time I have a good explore of the rest of the site to see what other knowledge I can steal. Hopefully one day I can return the favour and offer something that may help someone else out!