Gridlike pattern and focus on corners

[ftorres11]

Hey, recently I started working on GradCAM activations and on that topic I actually did my own implementation of GradCAM and ran EfficientNet through it, however I am not completely sure I get proper activations as I get a grid-like pattern and a special focus on corners when I try from EfficientNet-b4 onward. Here is an example of activations from ILSVRC2012_val_00011459.JPEG