The bird is obviously a Whimbrel, so this post is not about that.
I am someone who often adjusts posted photos in the hope of bringing out features that will help with ID. I think the large majority of my edits (and others do this, too) are useful. But sometimes I over-interpret my adjusted photos.
The Fern says that the Whimbrel's crown stripe can be seen, and Butty challenged this with claims about photo artefact lines. In this case Butty is right. Artefacts can be because of the quality of the camera and sensor, but can also arise because of light conditions, haze and so on. Harsh transitions (dark to light) can often cause a very thin border even with good equipment and software.
In this photo the Whimbrel's head is if anything tilted away from us, and the crown stripe is not visible. As Butty says, there are very thin, maybe only visible on a large-ish screen, white line artefacts along the head and back (and I would add tail, and almost certainly bill) of the bird in this photo.
Given that the bird is a straightforward Whimbrel, I don't think there was any need for Butty to point this out. But since he has, and since I sometimes use details like this myself for ID, I would just say that I think Butty's remark on the very thin white line feature is correct in this case.
In the first attached image, I have marked the head and back lines that Butty mentioned with a blue line, and the tail line with a surround. The second photo is the same without these markings - see if you can find them now they have been pointed out. The third photo is RitchieTwisty's edit with arrows marking the white lines.
