Luminous Landscape Forum

Raw & Post Processing, Printing => Digital Image Processing => Topic started by: John V. on August 03, 2012, 07:59:57 pm

Title: Removing light reflection in photoshop
Post by: John V. on August 03, 2012, 07:59:57 pm
This might not be the best place in the world to be asking this, so if anyone can recommend a good photoshop forum, by all means please do...

It looks like the majority of the left side of the attached image is reflecting light from the photographers set-up. Can anyone point me in the right direction as to how to go about correcting this?

John
Title: Re: Removing light reflection in photoshop
Post by: ErikKaffehr on August 03, 2012, 08:06:46 pm
Hi,

I would try to select the reflections by color and than remove using content aware fill. May work or it may not.

Best regards
Erik
Title: Re: Removing light reflection in photoshop
Post by: Lightbox on August 03, 2012, 09:05:38 pm
Being a reproduction of an artwork it really should be photographed in the right way from the start to ensure accuracy of colours, but to fix the current image is fairly easy. Open in Photoshop and create a new Hue/Sat layer, set blending mode to Multiply and make sure the mask for this layer is filled with black.

Start with a large soft brush and paint in on the mask where you want to correct ie. left hand side of image and a small amount in the top right. Now open up the adjustment panel for the Hue/Sat layer and desat blues, cyans & magentas, then give yellow some saturation to suit. Above this layer create a new Levels layer and use the same mask as you have created for Hue/Sat layer, adjust the levels layer to add a small amount of contrast to suit.

Many other ways to go about fixing the image but this one quick and simple and addresses colour and lighting in a small amount of layers, I really like using the Hue/Sat layer in Multiply when I want to seriously darken an area as you can adjust the colour variations of the darkened area at the same time.
Title: Re: Removing light reflection in photoshop
Post by: John V. on August 03, 2012, 09:17:48 pm
Saturday project it looks like. Thank you both mucho.
Title: Re: Removing light reflection in photoshop
Post by: bill t. on August 03, 2012, 11:54:51 pm
Or just use the rubber stamp tool to fill in the bad parts from similar good areas.

First make a new layer over the image layer, switch to that new layer, then do all your rubber stamping on the new layer.  Make sure the stamp is set to "Current and Below" up at the top of the PS window when the rubber stamp is selected.  Makes it easy to go back and fix mistakes without modifying the original at all, just erase any parts you want to fix with the eraser, staying at all times on the "new" layer that will hold just your repairs.  You can even toggle the visibility of the repair layer on and off to see how you are doing.  And if you want you can have multiple repair layers.

Not very glamorous, but it works.
Title: Re: Removing light reflection in photoshop
Post by: Dave (Isle of Skye) on August 07, 2012, 04:27:02 pm
John, do you mean something like this?

Only took me about ten minutes to do this, but I did use some quite advanced PS techniques, which would take me quite some time to explain, but I think this is about as near as you will get without re-shooting it using a different lighting setup. If you are doing this for a client, then I think they would insist on it being exact in every way, so I would advise re-shooting.

Dave
Title: Re: Removing light reflection in photoshop
Post by: Mark D Segal on August 07, 2012, 05:48:45 pm
Nice job. Whets the appetite for a few bullet points on the key moves to get there.
Title: Re: Removing light reflection in photoshop
Post by: darlingm on August 08, 2012, 01:10:31 pm
Nice job. Whets the appetite for a few bullet points on the key moves to get there.

I'm hungry for bullet points!
Title: Re: Removing light reflection in photoshop
Post by: John V. on August 08, 2012, 02:01:12 pm
Very nice to know that it is indeed possible, and thanks for taking the time to do this Dave. I would love to know how you went about it.. Maybe a screen capturing program to make a video of the steps as you do it in photoshop? I could help you out with setting this up, and it wouldn't require much extra effort on your end. I will look around at some options in case you are willing to do this.

The painting is actually held at the Seattle Art Museum and they will only use their in house photographer. Having a reshoot done would be be possible, but complicated.

Let me know,
John   



John, do you mean something like this?

Only took me about ten minutes to do this, but I did use some quite advanced PS techniques, which would take me quite some time to explain, but I think this is about as near as you will get without re-shooting it using a different lighting setup. If you are doing this for a client, then I think they would insist on it being exact in every way, so I would advise re-shooting.

Dave

Title: Re: Removing light reflection in photoshop
Post by: darlingm on August 09, 2012, 02:04:21 am
Well, here's how I'd attack it.  I know I'm not the most advanced Photoshoper, so there could be a much better way.

(http://s17.postimage.org/wh3tbcv0f/63_16_01cc_mine.jpg)

Without seeing the original, it's all guessing, especially on an abstract piece.  Is mine or Dave's more accurate?  Which method is best?  Who knows, it's each our 5 minute interpretation of how we think it should look.  All we know for sure is the original photograph looks wrong.  I definitely agree with Dave that it's worth the trouble of having it re-shot.  If they have one dedicated photographer that they use, he should be able to get the lighting better..... But I know that might be hard to say.  You can always make a bad image look better, but starting with a good image will get you better results every time.  And, I really hope he took a high megapixel image!

A soft light layer can be used to selectively darken an image, and in this case that works well combined with the gradient tool.  In a soft light layer, dark is going to darken what is underneath it, 50% gray won't change it, and white is going to lighten what is underneath it.

To start, I want to darken the left of the painting.  I set my foreground color to black (LAB 0, 0, 0) and my background color to 50% gray (LAB 50, 0, 0).  I created a new layer, made it the current layer, and set it to soft light blend mode.  To use the gradient tool, we're going to click and drag, with the initial click at the point we want to start the gradient at our foreground color (black), and releasing at the point we want to end the gradient at our background color (50% gray.)  We want the gradient to only change horizontally, so when we're moving the mouse to the release point, we need to hold down the shift keep to ensure the cursor creates a straight left to right line.

This step is definitely subjective, and would require seeing the original to get accurate, but eyeballing it can make it look substantially better.  I chose to start the gradient 37 pixels in, and stop it at 406 pixels.  (You can open the info panel, click the down arrow and choose panel options, and change mouse coordinates ruler units to pixels to see where you're at.)

If you feel the positioning of the gradient needs to be changed, you can just draw it again.

If you feel there's too much darkening, you can either make the foreground color a very dark gray, or you can leave the gradient black to 50% gray and lessen your opacity percentage.  I feel there's too much darkening, and was happy with an opacity of 85%.

You can continue creating additional layers and creating additional gradients.  If you want to lighten, change your foreground color to pure white, and draw a gradient in a new layer.

I feel like the top right needs some darkening, so I drew a small 45 degree gradient there, by holding down the shift key and going at the 45 degree angle, although I lowered this layer's opacity to 22%.  I feel like the top left needs some darkening, so I drew a small 45 degree gradient there as well, lowering the opacity to 25%.  Last, I feel like the bottom left needs some lightening, so I changed my foreground to pure white and drew a small 45 degree gradient there, lowering the opacity to 30%.

If you want to do non-gradient type adjustments, you can of course make a soft light layer and use a 0% hardness brush, painting white, black, or a gray in localized spots.  If needed, you'd want to also experiment trying a low opacity brush, like 10%, and using multiple strokes to create a more even blending.

And, this is just a starting point to get the brightness in sync.  As I'm sure you know, there will need to be a lot more correcting needing to be done including colors.
Title: Re: Removing light reflection in photoshop
Post by: Mark D Segal on August 09, 2012, 08:39:34 am
Maybe not that much more is needed. A bit of contrast and saturation boost to the upper left side of the image would bring it more into line with the remainder.
Title: Re: Removing light reflection in photoshop
Post by: John V. on August 11, 2012, 04:37:08 pm
I'm going to play with this darlingm, and thank you also. Mark, noted :)

John