How can I Photoshop Oil into a Water Bottle?

Question

I've been working on a project where I need to fill in a bottle of water with thick, black crude oil (it's supposed to be a visual metaphor).

I initially found this question, but following its instructions only got to this:

This website makes the bottle look darker than it actually is. When I play with the levels, it either looks too posterized, compromising the image's integrity, or like gray transparent water. Basically, I can't seem to get the black thickness similar to the bottle in the other question. I think it may be because of how the water bottle is lighted, so maybe I need a different starting image.

But I'd like to know if this is possible to do? Or would it be a better idea to just make fake oil from scratch and take a photo over white drape?

Here's a link to the original bottle, the website causes errors on the image https://i.stack.imgur.com/2xwrE.jpg

Thanks

Answer 1

[BEFORE BEGINING THIS MAKE SURE THE BOTTLE IMAGE AND THE IMAGE YOU ARE SAMPLING THE COLOUR FROM ARE IN THE SAME COLOUR SPACE (RGB/CMYK etc))

Doing a google search for crude oil colour I came up with this images

I then selected a part of the 4th bottle and saved it as a seperate file.

Going to Image>Adjustments>Match Colour I saved the statistics for this file.

Before applying the Match colour on the bottle you will need to do some tweaking to the file. You need to flatten to some extent the black/grey/white in the image. First remove the background (you'll notice a part of the bottle missing on the right near the top, you can take extra care when removing the back) then seperate the cap from the bottom in to two layers. (you only need to apply a colour match to the oil not the cap)

With the oil layer highlighted, go to Select>Color Range> and using the colour picker tool click on any white part in the bottle. Using the brush tool fill this selectiong with a grey slightly lighter than the grey part in the bottle.

Go to Image>Adjustments>Match Colour and load the file you saved earlier and click ok.

After this using Saturation, Levels, Brightness Contrast etc you can tweak this to your desired colour. You could also take a sample from the any of the bottles in the initial image and follow the same process.

Answer 2

You can maybe try not to 'fill' the bottle to the top. Crude oil isn't entirely black either, it has a really dark brown color.

The reflections on the bottle is too harsh.

Here is a link to a file I quickly made that will explain a approach you can use. oil.psd

Hope it helps