Setting a black point to match other footage

Hi all - I have a studio shot that uses a black curtain I'm trying to mask and composite over a single very dark grey solid. Instead of having to match the blacks by eye to this solid colour I'm trying to blend it with I was wondering if there is a way to set a black point and eyedrop the colour i wish to match in the same way you'd set the white point in the colour tab with the eye dropper tool.

A screenshot of the comp hopefully showing what I'm trying to do is attached. Thank you (I am on Studio 18.1.4

black mask.png (504.6 KiB) Viewed 605 times

I think my approach here would be to Luma Key out the black entirely.

I think my approach here would be to Luma Key out the black entirely.

Thanks Jim - i considered this but there's so much similar colour in the products themselves that I'm filming.

I would use scopes and check the black levels there. Takes less than 2 seconds to do.

OK.

Have you tried the Object option in Magic Mask?