implements for magic research

[King of Nowhere]

my players are doing some field research on magic; having a world with a fairly advanced magitek and a scientific method, i wanted to give them some specific instruments. both for worldbuilding and immersion, and to put some more clear boundaries on what they can try to do.
so far I came up with

- thaumometer: this item measures magic fields around objects; it looks roughly like a spectrometer.
you put an object to be analyzed inside the closed chamber, and flash a light on a prism. the instrument will channel the light through the chamber, and it will measure its refraction. magic fields refract light, so this instrument can measure very precisely the intensity of the magic field. making the measure on different wavelenghts, it can also identify the various subschools of magic involved.
- wild magic detector: this looks like a frame wire with a thousand butterflies on top of a box.
the butterflies are metal replicas, but wild magic can temporarily animate them. when it does, they flap their wings, lifting the frame. the box contains a very sensitive weight scale, by sensing how much the frame is being lifted it gives a good estimate on how active the "butterflies" are, which is a good measure of wild magic.

besides measuring the magic field, though, what could you do with it? any suggestion for more instruments will be appreciated.

[Vahnavoi]

What exact implements you'd use for "magic" depend on rules of physics that govern it. Here, you've already made the decision that "magic" is powered by a field, analogous to a magnetic field, and that second device you describe is essentially a fancy magnetometer . There are many variations you could do on the same idea, including a compass needle that points at the direction of locally strongest magical field, and a spinning wheel that spins while you move within a magical field, spinning faster in stronger fields and being a simpler version of the butterfly box. The spinning wheel, in addition to a measurement device, can obviously used to work in a manner homologous to an electro-magnetic motor. It can also be weaponized, in the form of Warlock's Wheel, as invented by Larry Niven. The Warlock's Wheel draws magical energy from environment to spin ever faster, potentially exhausting the field if that's possible.

[LibraryOgre]

...calipers?

[TeChameleon]

A stuffed alligator hanging from the ceiling is necessary (nobody knows exactly what it does, but magic research doesn't seem to work without it. Maybe it's an ambience thing?)

A Probability Interference Scope- basically, the higher the background magic, the less randomization happens, albeit in some truly odd directions. The most basic of these would generate random numbers, and the less random they become (typically by repeating a familiar number sequence), the more magic is present. If it's all just the same number over and over, there's probably a deity of some description in the room. In a pinch, a character can simply flip a coin. If it comes down on one side over and over and over a truly improbable number of times, there's a lot of magic present. If it just rockets into the sky and vanishes, it's probably time to run.

Crowley's Canary- a life-size canary golem, made of delicately balanced crystalline runes. If magic reaches a hazardous level, the canary breaks. If magic reaches truly hazardous levels, very very quickly, the canary grows to the size of a building and starts breathing fire.

Runes of Residuum- a dense block of overlapping runes that looks a bit like a QR code on a stiff card, when waved in the vicinity of a (relatively) recent spell, the relevant rune will react and glow, standing out amongst all the others.

[MoiMagnus]

What are the major category of scientific instruments (other than basic tools)?

(1) Measurement. You already got those ones in your suggestion.

(2) Recording. How is scientific data automatically stored? Self-writing book? Illusionary text? An hologram that copy the exact behaviour of the experiment?

(3) Isolation and Sterilisation. The core of the scientific method is reproducibility. And there is nothing worse for that than interference. You need ways to isolate a part of the room from magical interference, a way to clean your hand and tools from possible magic substances, etc.

[Vahnavoi]

Extrapolating from those:

2) Recording: one of those spinning wheels, or a pendulum, attached to a pen, drawing an oscillating graph based on how fast it is spinning or swinging, based on strength of magnetic magical field. Allows tracking and recording changes in the field by time. Related, same machine but fine-tuned to react to only specific type of field. Allows for tracking and recording of multiple different fields.

3) Isolation and containment: some equivalent to Faraday's cage. Could be as simple as a lead-lined room. Another fantasy favorite: crystals. "Magically safe" facilities would be surrounded by crystals blocking or emitting cancelling fields, arranged in wavebreaker formations. Additionally or alernatively, you might have lead rods placed in the ground. You might want to think of what materials are magical or anti-magical at this point.