Regions of DP1 images which have been significantly overexposed or underexposed are often recoverable using Sigma Photo Pro. I'll give a couple real world examples of this remarkable exposure latitude.

I was at a friend's wedding yesterday. We were in the dark hall of a castle, waiting to toast the bride and groom. Thinking I had set my DP1 for ISO 800, I dialed in f/4 and a shutter speed of 1/10th of a second, which is about as long as I can hold the DP1 steady. Even if I had set the ISO as planned, the resulting photo would have been at least a stop underexposed. Unfortunately, I had left the camera at ISO 100. Here is the resulting image, straight out of SPP with no manipulation other than resizing:

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With any other compact digital camera I have owned in the past, that file would have been a complete loss. After pushing the X3F exposure maximally, processing using the SPP monotone conversion, adjusting levels/curves in Photoshop, and resizing, here's what I got:

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With the DP1, I was able to pull enough out of the shadows to preserve the memory of the occasion.

So that's the shadow latitude, what about the highlights? In Part 2 of the DP1 Shootout, I gave a sample of the DP1 highlight retention at ISO 100. However, the highlight recovery at higher ISOs can at times be shocking. Here's one example from Satuday afternoon at the National Museum of Natural History in Washington, DC. Shot at ISO 800, f/4, 1/10s. Original image with no manipulation other than resizing:

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After processing in SPP:

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I suspect that the DP1 is using an "underexpose and push" method, similar to Canon's Highlight Tone Priority, to achieve high ISOs. No other reason comes to mind for why the high ISO files show far greater highlight recovery potential than do the ISO 100 images. Whatever the explanation, the DP1, as compared with either the Canon 5D or Olympus E-420, seems both less prone to blow highlights at high ISO and more able to recover them. The downside is that the DP1 shadow recovery is somewhat compromised at high ISO. It's a tradeoff I'm happy to accept, with results that are generally more "film-like" than I am used to seeing from digital cameras.