OpenSeadragon Magnification Strategy for Lens

I’m working on some tooling for an OpenSeadragon-powered app that allows a user to apply different levels of magnification inside a “lens” area. My strategy has been to create two Viewers: one visible at current zoom, another hidden at the magnified zoom level:

Example lens magnification

The good news is that things work, but at some cost to performance (esp when I try to do any pixel manipulation to image data). For anyone familiar with OpenSeadragon, is it a bad strategy to build two viewers? I can provide some code for context, but I think this might be a conceptual question.

Also for those of you familiar with the source code, it looks to me like requestAnimationFrame is applied to OpenSeadragon animations from functions like zoomTo() or panTo() – is that a fair reading?

Any insights welcome! Thanks! Be blessed!

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