Panoramic touch-up

[Fotografer]

So I was on a backcountry trip in the Tetons and took this panoramic shot. Definitely showed my amateur status in the realm of photography by shooting all the shots in automatic, thereby getting a broad range in darkness/color. I still really like the shot itself and was wondering if there was an easy way to fix this so that the shots/colors flow into one another and there aren't those ugly lines at the stitch areas. Remember I am still an amateur photog with an amateur photog's equipment/software (a.k.a no software) so I won't have access to pretty systems like Photoshop.</p>
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