Open Disk Utility (in your Utilities folder)

Go to File -> New blank disk image

A "Save..." style dialog will pop up. Choose your Time Capsule as the save location and give the disk image a name ("Data on Time Capsule" or whatever you want)

Choose a volume size (there are several presets but in your case you'd choose Custom and pick your size. Leave Volume Format to default (MacOS Extended Journaled). Choose if you want it encrypted or not (you'll have to enter a password to access it, but it'll be safe from prying eyes). Leave Partition at its default and Image Format as read/write.

Click Create and it'll make a disk image on your Time Capsule of what ever size you've chosen (say, 200GB ). This will use 200GB on your Time Capsule, but that space will be safe from being used up by Time Machine backups.

To read/write data to this disk image, open the Time Capsule drive in the Finder just like any other drive and double click on the disk image icon with the name you've chosen. It'll mount on your desktop like any other drive of 200GB in size (or whatever size you've specified); you may then copy/save/create/delete/etc. any data you choose on it.

kao što piše u uputama, ovaj "sparse image" koji si napravio je u biti rezervacija mjesta na TCu tako da ga Time Machine ne "pojede". Drugi riječima, što je particija veća Time Machine će imati manje mjesta za backup. Dakle ako želiš više mjesta imati za backup onda taj image koji je napravljen preko Disk utilitya mora biti manji.

E sada pripazi jer nisam siguran 100% dali se može tek tako smanjiti koristeći navedeni utility bez gubitaka podataka. Znam da se može extendati bez problema ali nisam siguran sa smanjivanjem.

Dakle ako već nešto podataka bude bilo na toj particiji (sparse image) onda svakako napravi backup prije nego kreneš smanjivati particiju preko disk utility-a. Iskreno mislim da neće biti problema, ali bolje biti siguran.

Što se tiče uklanjanja te particije, samo je obriši i TC će cijeli prostor koristit za backup