This question already has an answer here:
I have a Nikon COOLPIX P7700 and because it has been losing function due to wear and tear after 6 years, and I wanted a better zoom range for wildlife, I decided to get a Canon 77D DSLR so I could get myself a more powerful camera that could have a really long zoom range and be of high quality. Although the kit lens isn't telephoto, it advertises a mm range of 18mm to 55mm range while the Nikon advertises 6mm to 42.8 mm. Although 55 on Canon isn't much more than 42.8 on Nikon, I thought it would still be a little further optical zoom than the Nikon's. Yet the Nikon displays an image much more zoomed in than the Canon's (keep in mind I've disabled digital zooms for both cameras but am pushing them to their maximum zoom). How/why could this be? I'm completely lost because I thought more mm = more zoom, and in fact you're supposed to multiply 1.5x on Nikon and 1.6x on Canon, so Canon should be significantly stronger.
This picture is a comparison between the two. I've digitally zoomed into both photos to show them at equal size. As you can see there's more grain and warp on the Canon photo because I had to digitally zoom in more, as the optical zoom was weaker (and my question is: why was it weaker if it was 55mm vs Nikon's 42.8mm?)
Thanks for the help!