Tag Archives: PSF

A practical guide for adaptive optics

There is no standard curriculum to learn practical procedures about microscopy: how to align a setup, how to identify misalignments, how to identify broken parts, where to buy components, how to check their performance, and much more. How to learn … Continue reading

Posted in Imaging, Microscopy | Tagged , , | 1 Comment

Review: An artificial ground truth for calcium imaging

Selected paper: Charles, Song, Tank et al., Neural Anatomy and Optical Microscopy Simulation (NAOMi) for evaluating calcium imaging methods, bioRxiv (2019). What is the paper about? Calcium imaging is a central method to observe neuronal activity in the brain of … Continue reading

Posted in Calcium Imaging, Data analysis, Imaging, Microscopy, Neuronal activity, Reviews | Tagged , , , , | 2 Comments

Photon yield and pulse dispersion

This case report describes how a two-photon microscope was found to come with a fluorescence yield that was lower than expected; how the underlying cause was found out in a systematic manner; and how the problem was solved. All approaches and solutions are specific for the microscope under question. However, I hope that this report (1) will inspire other people who are troubleshooting or optimizing their microscopes, (2) will help other people better understand two-photon microscopes and the relevance of technical details. Continue reading

Posted in Calcium Imaging, Imaging, Microscopy | Tagged , , , | 3 Comments

Springtime for two-photon microscopy

Today, the fields and forests around Basel are full of flowers that try to disseminate their pollen. Fixed pollen are, apart from sub-diffraction beads and the convallaria rhizome, one of the most commonly used test/reference samples for fluorescence microscopy. This … Continue reading

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Can two-photon scanning be too fast?

The following back-of-the-envelope calculations do not lead to any useful result, but you might be interesting in reading through them if you want to get a better understanding of what happens during two-photon excitation microscopy. The basic idea of two-photon microscopy … Continue reading

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Point spread functions

One way to characterize the quality of one’s microscope is to measure the point spread function (PSF), that is the image that is created by a point source  (which can be a fluorescent bead smaller than the expected size of the … Continue reading

Posted in Microscopy | Tagged , , | 3 Comments