These images are fine, just underexposed because the metering tried to set the bright white ice to the 18% mid point between full black and full white. Just add a couple ev of exposure compensation on the camera or in post. Here is one with a bit over 1 ev boosted and a bit of .5 pixel radius sharpening. A large full size file would have revealed a lot more detail that the sharpening brought out.
Stan
St Petersburg Russia

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Attachment #1, (jpg file)