Learn Russian: По-вашему, у аналоговой фотографии контраст лучше? - In your opinion, does an analog photograph have better contrast?

You would use по сравнению с (in comparison with / compared to) followed by the Instrumental case. 'Digital photography' is цифровая фотография, which becomes цифровой фотографией in the Instrumental. You could attach it to the end: По-вашему, у аналоговой фотографии контраст лучше, по сравнению с цифровой фотографией? (or just по сравнению с цифровой to avoid repeating the noun).

Why does По-вашему have a hyphen here?

По-вашему is an adverb here meaning 'in your opinion' or 'your way'. In Russian, when the prefix по- attaches to a possessive pronoun ending in -ому or -ему (or adjectives ending in -ки, -ьи) to form an adverb, it always requires a hyphen. If it were a preposition followed by a pronoun modifying a noun (like 'according to your plan' — по вашему плану), there would be no hyphen.

Why are we using the у + Genitive construction (у аналоговой фотографии) instead of a verb like иметь (to have)?

While иметь does mean 'to have', Russian strongly prefers the у + Genitive construction to express possession or inherent characteristics, even for inanimate objects like a photograph. Using имеет лучший контраст would sound overly formal or translated, whereas this sentence represents a natural, conversational question.

Could I use более хороший instead of лучше to say 'better'?