Being quite a new convert to butterflies from 20 years of birding I am finding my first year quite hard. This is often because I am not sure where to look on a butterflies underside to figure out an ID.
I spent a top 9 days this July in Bulgaria and I am still going through photos from an overwhelming 117 species.
I believe this is an Adonis Blue, could anyone please confirm it and would anyone be kind enough to give me some pointers on how to ID the underside from a Chalkhill? I feel if I can see written down "instructions" my brain will be able to cope with them a bit better

Thanks in advance
Jon