ChimpStackr

ChimpStackr is free, open-source software for combining photographs made at different focus distances. It suits photographers who want both a desktop interface and a scriptable command-line workflow on Linux, macOS, or Windows. Its strongest case is precise, bit-depth-preserving processing; look elsewhere if you need a hosted service or documented support and compliance commitments.

Overview

ChimpStackr gives focus-stack users four processing approaches: Laplacian Pyramid, Weighted Average, Depth Map, and Exposure Fusion. The first three address focus stacking, while Exposure Fusion is intended for scenes with varying exposure or lighting rather than combining focus distances. That distinction matters: the method list is broad, but the HDR option should not be treated as another focus-stacking algorithm.

Automatic alignment can compensate for translation, Euclidean rotation, similarity rotation and scale, and affine changes. In practice, that range helps when a sequence shifts or turns slightly between captures. Auto-crop removes the black borders alignment can create, and auto-tuning derives parameters from image resolution, reducing setup work when moving between image sets.

Key features

The 16-bit pipeline keeps the source bit depth from RAW input through the output. Photographers preserving tonal detail therefore have a meaningful advantage over workflows that reduce precision during processing. Results can be exported as TIFF or PNG, and RAW files are supported.

The graphical application accepts dragged image files or folders. A comparison slider lets users inspect input against output, while pause, resume, and cancel controls make long stacks less disruptive. The headless command-line tool is useful for repeatable or automated processing without opening the GUI.

ChimpStackr is distributed as an open-source project under GPL-3.0. The project mentions example images post-processed in darktable, but does not describe a direct integration, so users should regard that as a compatible workflow rather than a built-in connection.

Pricing

ChimpStackr costs free under its single Free plan. It includes the multi-platform focus-stacking software and GPL-3.0 licensing, with no paid tier or trial requirement. That makes it a straightforward choice for individuals who can run desktop software and do not need commercial support terms. There are no published seat quotas, processing quotas, renewal charges, or free-plan caps.

Platforms

Native downloads cover Linux, macOS, and Windows: the releases page provides a Linux x86-64 AppImage, a macOS DMG, and a Windows ZIP. Building from source requires Python 3.9 through 3.13, and a build can target only the platform on which it is made. Those source-build constraints matter to developers maintaining deployments across multiple operating systems.

Who it's for

Choose ChimpStackr if you photograph macro, product, nature, or other subjects through a sequence of focus distances and want control over alignment and algorithm choice. It is particularly well suited to RAW-based workflows that retain 16-bit data, and to technically minded users who value a command-line path alongside a GUI.

It is less suitable for anyone seeking browser-based processing, mobile-first use, or a vendor-backed support arrangement. Users primarily combining different exposures should use its Exposure Fusion purposefully, not as a substitute for its focus-stacking methods.

Pros and cons

Pros

• 16-bit RAW pipeline: preserves source precision through export for detail-conscious editing.
• Four named methods: provides alternatives for focus stacks while also covering exposure-fusion work.
• Broad alignment controls: handles translation, rotation, scale, and affine correction.
• GUI and headless modes: serves occasional users and repeatable command-line workflows.
• Free GPL-3.0 distribution: removes licensing cost across all three desktop platforms.

Cons

• Exposure Fusion is not focus stacking: one advertised method has a different job and can mislead users expecting four equivalent stackers.
• Desktop-only releases: there is no stated Android, iOS, or web version.
• No stated support or compliance program: organizations needing formal assurances must make their own assessment.
• Source builds are platform-bound: cross-platform maintainers must build separately for each target system.

Alternatives

Focus Stacking Online is the better pick when browser or mobile access matters; it is free across Android, iOS, Linux, macOS, the web, and Windows. Choose CKAN instead if an MIT-licensed open-source desktop option is your priority. ImageFocus Alpha suits owners of compatible Euromex camera models. focus-stack is another free Linux, macOS, and Windows choice when you want a separate focus-stacking tool without stated usage limits. PlaneFuse is preferable for API, web, or self-hosted deployments and permits personal and commercial use under MIT licensing. ForgePix offers a free MIT-licensed desktop alternative. Open Galileo is Windows-only and presented as permanently free with voluntary donations. OpenFocus combines an MIT-licensed GUI for Windows and macOS with CLI support on Windows, macOS, and Linux.

Verdict

ChimpStackr is a strong recommendation for photographers who need free, cross-platform focus stacking with RAW handling, 16-bit preservation, alignment control, and both GUI and CLI operation. Its main reason to choose it is the combination of precision and workflow flexibility. Look elsewhere if you need online or mobile processing, formal support commitments, or an exposure-fusion tool that is explicitly designed as a focus stacker.