
Re: Best quality for indoor, long term
I use an Olympus OMD EM-5 for biolapse. Using the grip and AC adapter, it can run extended periods. While M43 uses a smaller sensor than Crop or Full Frame cameras, the image quality is extremely good and should be more than enough for your purposes.
check out my site
http://www.biolapse.com and check out the gallery and blog, (there are more samples in the blog than library) all the timelapse sequences in there were done indoors with an Olympus OMD Em-5. I ran into an issue with flicker, but that was due to the lighting not the camera and i have recently ironed that out.
You can use an eye-fi card to wirelessly dump images to a remote PC as it progresses so you can see the results without disturbing the camera.
the longest i have shot without interruption is about a week. But the camera had no problems with this.
The Olympus OMD EM-5 can be found at a discounted price as it has been discontinued with the newer OMD EM-1, but there is no benefit of the new model vs the older one for this type of work. They use the same sensor. You WILL need to find an intervalometer.