Is it possible to have a graduated filter that is both Luminance Range Masked and Color RangeMasked?

[#1]

Suppose I want a graduated filter that affects only the light blue, but not the green or red of a similar lightness?

Is this possible, even if it involves multiple filters or other "trickery"?

Also, please note, that for this purpose, I can't use the erase brush to get rid of the light green or light red, its too complicated a scene.

[#2]

Turn on the range mask, select color mask, use the tool to select blue.

[#3 · Accepted solution]

The 'Color' Range mask does what you ask.

By placing a 'pin' on light tones of a color with the dropper tool- you select only those luminance tones.

My example in screen-clips:

1) The original image

2) A Gradient applied over the whole image, with the overlay showing as 'Red'.

The first dropper pin is on the lightest tones of 'Blue':

3) A second dropper pin is applied to the darkest blues at the top of the image. Note the Mid-tone blues are not fully masked!

4) A third dropper pin is applied to the mid-tone blues. Now ALL the blue sky is effectively selected (with the red overlay).

  And -4stops exposure results as 

Adjusting the 'Amount' slider to the lowest minimum indicates better how the three pins are selecting different luminance tones of the BLUE color-