Guitar tuning

That is one of the “cons” to a Floyd Rose (or any floating) tremolo bridge system. There are things like TremSetter that can help minimized that, but if you want to be able to change tunings on a guitar with any frequency, you’re much better off with a fixed bridge solution.

Alright so you have a couple options here:
1: That is the solution if you just want to switch tuning. You could lock the floyd rose. What i mean by that is that you could take off the back plate, place a piece of wood or some lego bricks between to floyd rose and guitar body. By doing this, you basically just have a fixed bridge. That means that your floyd is locked so no more dive bombs or any use of the whammy bar whatsoever (anybody, correct e if im wrong) Little note, you must make sure that the bridge is still parallel to the body.
2: That is the solution to caliber your floyd to the tuning you want. You will basically make all the adjustement to have one and only one tuning on your floyd equipped guitar. if you want to change your tuning again, you will have to re-adjust all over again. So, there are a tons of ”how to” videos on youtube but long story short, you have to adjust the tension of the string and springs perfectly to the tuning of the strings by screwing up the screws under the backplate. This can be a hard process as to avoid de-tuning while playing, it has to be very well done so the tension of the strings and springs keep the floyd completely parallel to the body with the tuning of your choice.
Sorry for the long text but I hope it somehow helps! If im wrong on anything then anyone, please, correct me!
Have a good one!

Radu is correct, though there is a third option that works. It’s called a Trem-setter, and if you install it, it makes your trem work more like a restaurant’s kitchen door (always back to center, where it rests) than a full float. It definitely changes the feel of the bar, and going from standard to drop D will still draw the remaining strings VERY slightly sharp, but it’s a usable option. I have this installed on both of my Floyd-equipped Ibanez for that very reason, and while it’s not perfect, it is an acceptable solution.
The part itself is fairly inexpensive (about $40 US) but they are VERY tricky to install, so unless you’re a good guitar tech already, I’d recommend having it installed by a good tech.
https://www.stewmac.com/Hardware_and_Parts/All_Hardware_and_Parts_by_Instrument/Electric_Guitar_Parts/Electric_Guitar_Bridges_and_Tailpieces/Electric_Guitar_Tremolo_Parts/Hipshot_Tremsetter.html