Color Removal in Photoshop

Question

OK, so I'm wondering why there isnt the specific function to select a color or color range, and then use a slider to fade out a given color from the image
yes, I'm aware of Select > Color Replacement, but to be honest it does a superficially good job that doesnt hold up to close scrutiny when used as a method of dropping out background colors
Also, odds are whatever color or color range you are dropping out are also colors contained in the image you want to keep
Meaning half of your image may drop out to transparency as well
one way to quickly repair this problem is to duplicate the original image then just use a giant eraser to very quickly remove all but the main item you want to keep, then, run the eraser around the entire edge, hoping no important pixels go missing around the edges.. I use this all the time.
another quick repair is to create a new back-ground layer that is similar in single color to the multiple colors you removed and then use the eraser to run around the edges quickly.. I've used this on many occasions too
another quick repair is to duplicate whats left of your image about 20-50 times, then merge all those layers, and perhaps touch up with a brush on an underlayer to replace any missing background color
of course, the problems with these methods, which I like to call my "Insta-Mask" methods, is that edges around the object look terrible at a full contrast B/W Mask level...there's actually just alot of noise, because of the transition in photographic images from one color or object to the next.. and its like that for most any image thats not purely a graphic..
its good for sliding away with something thats not too important that you need done quick, but thats about it
.. And I understand masking, Channel Duplication, Combination, Calculations, Blending Modes, Levels, Variations, Opacity, Hardness, Edge Refining, Contracting, etc, etc, etc.. and yes, I Can make very beautiful masks for most any object regardless of how blended in with the background it is.. I owe that largely to my days using the First Version of Photoshop, when basically everything we did was at a Pixel level, and I do quite enjoy it (though its time consuming), as well as the tools available for making it alot easier
And I dislike the Magic Wand immensely, for removing colors, and it only works with a couple kinds of images/graphics, and even then, its not really that nice at all
I also do Pen Tool Masking from time to time, as the situation requires
but there is a function missing in Photoshop , which its capable of doing, which would make things alot easier, but which hasnt been included to date.
and that's the ability to drop out colors or color ranges BASED on Tolerances to the adjacent color pixels, with a feather & Refine edge function
This should of course be equivalent to true pixel masking, and simply and easily drops a color out of existence in your background without dropping all that color from your entire image, and without you having to use the tragic wand and other crude, general selection tools which ruin the masking field
I mean, I dont see why its not there
or simpler yet, just a slider that lets us drop out certain colors to transparency, would be a great start

Answer 1

imagine you could use the marquee tool or a selecting-brush to drag or brush over some background elements, weeds in a field, Mountains, Buildings, Skies, etc.. adding the selected colors & patterns to the number of colors & objects to be removed..
then use the same brush to brush over colors & elements you want to keep, and the values for those colors are stored separately, even if some of the values are the same
then, you drag a brush around the object you want to remove from the photo, where the object meets the background, which must have a start-point, and an end point which returns to the start point..
Photoshop then calculates the location of items to keep as inside the closed brush line, and items to disappear as outside that brushed line
Tolerances can be individually set with an Eye-dropper between a blue shirt sleeve you want to keep, inside the brush mark, and the blue sea, blue car, or blue sky adjacent to that sleeve, outside the brush mark,..
you can add another combination of "Near Tolerances" by clicking "Add a Near Tolerance", then you select the green shoes inside the line, multi-select add, then click next, and click the green grass outside the region.. also additive multi-select
Photoshop then remembers the regions, the colors, patterns, and values, and all the other information you gave it (the only real important thing being what happens directly under the brush line you painted around your object, as it will automatically delete everything outside of that), click "Extract" and the object of your desire is removed perfectly