Changing or altering the color of a selected object

[joelh33703351]

I am using the latest version of PS on an Acer desktop. Because I am new it has taken me some time to learn how to ask a question of the community. In this example I am just trying to change the color of a figure to make it darker but because I do things like say I want to make it "black" I get conceptual answers about how black isn't a color which is helpful but doesn't get me across the finish line. I am more pedestrian and because I have PTSD whenever I open PS I am more plodding. I have attached the image I am trying to alter. All I want is for one of the figures to become darker, closer to black. Here are the steps I am following with an indication at the end of why I can't go further:

1) Using the lasso tool I select the figure. When the circle is closed the line pulses so I know I have selected it

2) I go to Select across the top bar (the op?) and find Color Range. 

3) Clicking on Color Range a dialog box opens and using the eye dropper I click on the figure so that the only thing that will be changed is the figure. I click OK

4) Under Window I choose color and a dialog box opens up in the upper right hand corner and I click on the darkest hue I can find. I notice that in the lower right of the two boxes, there is a white box but the other box changes to something darker (see I am trying to avoid saying black)

5) Then I go back to the top menu and under image, I chose Adjustments. Now I can either (according to people who have responded to earlier posts) choose Hue Saturation or Selective Color. However when I do either I get an error message: "Selected area is empty" . The figure btw is a layer. 

What am I doing wrong or need to do differently to change the color to darken the selected figure?

[Trevor.Dennis]

There are lots of ways to do this in Photoshop.

I have four idential Shape layers in this image.  If I select one of the layers, and click to open a Curves adjusment layer, than changing the curve will affect everything below that adjustment layer.

But if I click on the icon at the bottom of the Properties panel (my green highlight) then it only affects the layer immediately below it.

If I select one of the layers > Right click and chose Convert to Smart Object 

I can then go Filter > Camera RAW and make a huge range of adjustments.

What's more, because we are now working on a Smart Object, you can go back in and fine tune the edits you made non-destructively.   

[joelh33703351]

The conversion to a smart object and then choosing filter, camera raw and the curves allowed me to darken the layer, the other solution did not work as the curve adjustment effected the whole image. thanks

[Trevor.Dennis]

Hi again Joel.

You have several options to restrict the effect to the layer below the Curves Adjustment layer.

Adjustment Layers  all have this icon that 'clips' the layer to the layer beneath it in the layer stack.

I have made part of the layer mask black so you can see before and after.

If you Ctrl (Cmd) click a layer's eye icon in the layer panel (my yellow highlight), it will load it as a selection, and you will see the 'marching ants' around the object.

If you then add an adjustment layer, it will automatically fill the rest of the layer mask with black, once again restricting the effect to just the object.  My apologies if you already knew that stuff.