This subproject is one of many research subprojects utilizing the resources provided by a Shared Instrumentation Grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the grant, which is not necessarily the institution for the investigator. DESCRIPTION (provided by applicant): This is a proposal to upgrade our one- and multi-photon laser scanning microscope system that is based on our Zeiss 510 NLO system. The upgrade consists of 1) the Chameleon, an easily use femtosecond pulse Ti:Sapphire laser to replace our aging and difficult to use Ar pumped Mira laser; 2) Zeiss Physiology software for the 510 system that allows more sophisticated image processing and analysis; 3) workstation software to duplicate the 510 analysis functionality on standalone computers so that our heavily used 510 system can be used for collecting data. Our Zeiss 510 system is in a heavily used multi-user facility that provides image acquisition and analysis for a wide variety of one- and multi-photon excitation projects. These upgrades are sought 1) to improve the reliability and ease of use of multi-photon excitation so that an average user can work independently; 2) greatly increase the speed of changing wavelengths of multi-photon excitation to allow novel experimental approaches; 3) provide increased software functionality on the 510 system; and 4) to make analysis functions available 'off-line' so that the 510 system can be dedicated to data acquisition. Our facility includes two other laser scanning confocal microscopes, a Zeiss 410 and a BioRad 600, and a spinning disk confocal microscope, from Atto Instruments. Our microscope systems are used for a variety of projects by investigators from several laboratories.