Hamana

Hamana is a lightweight piece of software designed to help you view a wide variety of images on your computer using advanced filters and in slideshows, if necessary.

Includes a tree view that can be counter-intuitive

The setup is a quick and straightforward process that entails decompressing the archive in any desired location on your computer. Upon launch, you may be a little confused about the role of the application and it would have been nice if it included some tips on how to get started.
Nevertheless, since the toolbar is enabled by default, you can use the arrows to navigate through the folders and contents without too much effort. Moreover, while the explorer panel appears rather small and crowded, it expands to display the large filenames as well, so you can find the photo you are looking for without too much hassle.
Unlike most photo viewing tools, the app displays the folders and subfolders you are browsing, instead of the path, whereas the files that you can view are highlighted with various colors. While innovative, the display can create confusion for first time users.

Provides you with several viewing modes

The highlight of the application stems from the several viewing modes it packs, namely original size, zoom in and out, rotate right or left, vertical reverse, twin images as well as numerous versions of fit. As you can check out from the View menu, you can use dedicated hotkeys to access the aforementioned viewing options.
The tool also allows you to browse your images in slideshows that include effects, such as turn, scroll, break, explode, blend and zoom or regenerate, for instance. In addition, you can check out how your photos would look with special effects like grayscale, sepia, nega, edge emphasis, unsharpness or different tone curves.

A useful tool for viewing images in an interesting way

In the eventuality that you are looking for a utility that allows you to preview images in a unique way and with special effects and filters, then perhaps Hamana might be worth a try.