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How to remove a slight Blue cast on a cut out


fredfish

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I used the pen tool to cut out a motorbike from the background (as much as a training process in developing my pen tools skills as anything) and I am fairly pleased with the results.

screen dump.jpg

However there are some parts that have understandably picked up some of the colour from the original background - this is most noticeable on the exhaust pipe.

close up.jpg

I would really appreciate suggestions on how to address this - I have tried selecting the area and then using hue / saturation to reduce the saturation levels in the Blue and Cyan sections of the filter but it really isn't effective.

What suggestions does anybody have.

Cheers

John
 

Tom Mann

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At first glance, from your screen grab, it appears to me that a slight orange cast is present elsewhere on the bike, as well. Unfortunately, one can't make good color decisions from a screen grab, particularly one like this that is not tagged with a specific color space. If available, could you please post the original raw image file. The easiest and highest quality color corrections are done at that stage.

Lacking the raw file from the camera, could you pls. post a JPG, appropriately tagged (ie, sRGB, AdobeRGB, ProPhoto RGB, etc.). It will probably be too large to post in the forum, but since we are only working with the colors, you can down-rez it to 3499 pixels wide, and it should go in with no problem.

Thanks,

Tom M
 

fredfish

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Hi Tom
Thanks for the quick reply. I know what you mean about the colour cast in other areas - I thought that at first as well. As it happens that is not from the orange background (I assume that you mean the area below and to the left of the Moto Guzzi logo on the tank as one example). Here is another image but with a different background colour and you can see that the cast I think you are referring to is still there.
Blue Background.jpg

The original image was one I found on the internet that was originally from a magazine. This is the original.
orgional gizzi.jpg.
The Image was just pasted into a new blank Photoshop document so I assume it is Adobe RGB.
I am assuming that the cast on the bodywork comes from the lighting in the original photograph.

Thanks again

John
 

Tom Mann

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I've got to run off, but in the interim, I assumed that (a) you probably wouldn't have the raw data file from the camera; and, (b) your screen grab was really an sRGB.

Given that, and only a few minutes to come up with the following. If you are interested, I'll be back at home tonight (East coast USA time).

HTH,

Tom M
 

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fredfish

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Thanks Tom

I think our last posts crossed. It is 1:30 pm UK time - I will check back later.

I appreciate you having a look. It may be my perception (quite possible - the eyes aren't what they used to be!) or it may be that it is on a white background, but the blue cast appears more pronounced in your image. It could also be the calibration on my monitor and or different colour profiles. So many variables!

As I said in my original posting this image was mainly for me to practice my pen tool operation and to cut the image from its original background - and this has certainly allowed me to do that. However as I am always keen to learn, when I noticed the blue cast on the exhaust I thought I would ask for some suggestions.
This isn't a big project or anything like that - purely academic - but any insight anybody could provide in the spirit of me developing my skills would be great!
I am not after anybody making the changes for me (although examples are always useful) I am more after suggestions of the processes so I can learn how to do it myself.

Many, many thanks for your input.

Cheers

John
 

IamSam

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Tom is absolutely correct concerning the image.

But, as an alternative and food for knowledge, you can target specific areas of color using Color Range.

Here are the areas in question that I have isolated....
Screen Shot 2016-07-12 at 8.01.45 AM.png

Here I have used a Hue & Saturation adjustment layer. When the adjustment layer is added with an active selection, a layer mask will be created on the Adj layer.
Using the colorize feature, I then changed the color of the selected/masked areas.
Screen Shot 2016-07-12 at 8.02.42 AM.png

I made the purplish to match the new BG.

Screen Shot 2016-07-12 at 8.09.16 AM.png
 

fredfish

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Thanks for the input Sam

Select by colour range is something I am familiar with and use frequently - what I was missing (I think - as I haven't yet tried it) was to check the colorize box, I was, after selecting the area, just adjusting the Blue and Cyan sliders without checking the colorize box first.

Just as an addition - when I tried it myself earlier (without using the colorize box) I promoted the selection to a new layer after adding some expansion and feathering to the selection. Then I clipped the new adjustment layer just to the promoted layer.

Many thanks for the input.

Cheers

John
 
Last edited:

fredfish

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Thanks for the suggestions guys - I did the following:-

Used Select by colour range to select the offending areas
Selected Selection/Modify/Expand and expanded but 2 pixels
Selected Selection/Modify/Feather and feathered by 3 pixels
Ctrl + J to promote to its own layer
Created a Hue / saturation fill layer and clipped it to the layer below (my new selection)
Clicked on the Colorize option
Selected a hue close to the background
Tweaked the saturation and lightness options
Ended up with this - which is pretty close to what I wanted.

Orange background.jpg

The background really doesn't matter - I fully intend dropping the bike on to another background, play with adding shadows, lighting etc...... I just wanted to get rid of the colour cast.

Thanks for the help and suggestions.

Cheers

John
 

Tom Mann

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This will teach me not to dash out an answer to a request when I'm pressed for time, or, at the minimum, at least read the thread title more carefully, LOL.

From the following quote and a quick glance at the image, I thought that we were supposed remove the orange reflection on the muffler.
...However there are some parts that have understandably picked up some of the colour from the original background - this is most noticeable on the exhaust pipe. ...
Of course, if I had at least paid attention to the thread title, I would have realized that the OP was after the smaller blue reflections. Of course, given my inclination to cold, bluish metals, I proceeded to nuke the orange and jack up the blues, exactly as John observed.

Mia culpa, Mia maxima culpa!

Please return to our usual high quality programming, as provided by Sam, but if you are ever interested in making chrome steely blue, and whites that are whiter than white, just give me a call, LOL.

Cheers,

Tom M
 
Last edited:

fredfish

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No sweat Tom - I genuinely appreciated the input..... may well come back and pick your brains about chrome in the future.

Thanks again

John
 

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