Here are some samples taken with the new Camera app.
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I guess it all depends on the user and/or the phone. Not having the fancy "HDR" features/effects of Lumia Camera 5 is alright for me (I dislike it). Color fidelity and reproduction, as well as image quality have not changed in my Lumia 1020. The only differences I can tell from Lumia Camera to the new Windows Camera are the increased launch speed and added camera button features (press and hold for _____).
I have other photos to share, but the resolution is too large to upload here... and I've got other things to move on with. Still, the best comparison should have a concrete base line or reference point, i.e. photos taken of the same subject under the same conditions... best if taken at the same time using the two camera apps using the same device model. I can't do the comparison since I only have one Lumia 1020.