The Zeiss Lightsheet 7 is used to quickly and efficiently scan large tissue volumes using laser light sheet illumination. The focused laser sheets and imaging plane are static while the tissue is moved throughout the selected volume for three dimensional image acquisition. This protocol will cover the procedures used for the day of light sheet image acquisition. Setting the acquisition volume: Large scanning volumes are composed of multiple z-stack being stitched back together based on overlapping edges of the scanning window. This requires setting an overall z-stack, which must include the entirety of tissue as covered by adjoining z-stacks. This becomes tricky when considering irregularly shaped tissues and their orientation relative to the various laser and imaging objectives. Dual-side light sheet alignment: To obtain a strong and clear image from large tissues it is helpful to illuminate the sample with both the left and right laser. Each laser sheet can be angled slightly within the focal plane to account for differences in the R.I. of the tissue and R.I. media (TDE). This is a manual tuning process and is not intended for major R.I. differences. Protocol Overview: - Refractive index matching of cleared tissue samples. - Mounting tissue onto sample holder. - Image acquisition in Zen 3.1 LS (black edition), including: - Setting the acquisition volume - Dual-sided light sheet alignment