With Nokia finally filling out its product line with new Lumia 920 derivatives for other wireless operators, a clear strategy emerges: Nokia is betting that its vaunted reputation in camera optics will help sell its high-end smart phones. But Nokia’s strength in this area isn’t just about the camera hardware: Users of Lumia 92x handsets also benefit from ongoing software updates, low-light camera performance, and apps that work together in unique ways.

With the original release of the Lumia 920, this vision—so to speak—was only partially realized. While many had argued that the Lumia 920 camera was the best of its generation, my own tests showed something a bit more nuanced, and I judged the iPhone 5 camera to be superior overall. But over time, Nokia has actually worked to close that gap. You can see some of these improvements in software updates for the device, and in individual camera apps. But one of the new 920 derivatives, the Lumia 925, also includes a critical hardware change that could make a major difference as well.

Two Lumia 920 firmware updates are notable from a camera perspective. In December 2012, Nokia issued a firmware update that fixed a fuzziness problem with the camera in devices with the original firmware revision. Then, in April, Nokia issued a firmware update for the Lumia 920 (and for the 820 and 620 as well) that included, among other things, enhanced camera performance with corrected exposure when the flash is used in bright light conditions. Given the 920’s excellent low-light capabilities—see below—it seems that this update was designed in part to address other (perhaps more common) lighting conditions in which the device didn’t previously excel.

Regardless of these changes, the Lumia 920 camera has always excelled in two key areas: low-light conditions and optical image stability during video recording. While I can’t claim a lot of experience with the latter, I’ve certainly noticed the low-light performance many times. This camera does indeed take fantastic low-light photos, as I noted in my review of the Lumia 920.

But time marches on. And over the past few weeks, Nokia has announced two derivatives of the Lumia 920 that improve matters in some ways.

The Lumia 928 will be offered via Verizon Wireless in the US. Looking strictly at the camera, the 928 offers nothing new: it has the same 8.7 megapixel sensor as the 920, the same low-light performance, the same feature set. But the 928 does have three high-audio-amplitude-capture, or HAAC, microphones that should record distortion-free audio even in noisy places, an improvement over the 920.

The Lumia 925 is further-reaching with regards to the camera. (This device will be sold through T-Mobile in this country.)

First, and most important, the 925 adds a sixth glass lens to the set of five lenses that grace the 920 and 928. Nokia says this provides pictures with better clarity, especially in daylight, so this too seems aimed at addressing one of the few issues with the 920/928 camera. The 925 also includes a firmware update that reduces photo noise in low-light conditions, improves color accuracy, and raises the effective maximum ISO from 800 to 3200, four times higher.

The big deal here, I think, is deep-seated changes to the image processing algorithms used by the Lumia camera that enable these improvements. The changes build on previous software-based changes that Nokia has made to the Lumia 92x camera, and it’s perhaps not a stretch to make the comparison to the Hubble telescope, which needed tweaks of its own after being deployed in space. Conventional wisdom suggests that the only real way to improve a camera is with new hardware, but Nokia has proved repeatedly that this isn’t the case.

Most important, this firmware update, codenamed Amber, will be delivered to 920/928 users as well, Nokia says.

Looking beyond the actual camera, one of the more interesting enhancements being delivered with the Lumia 925 has nothing to do with the device itself: Nokia is also providing a new lens app called Smart Camera that takes a burst of 10 photos at once, which seems similar to features available in other smart phones but in fact goes quite a bit further. Smart Camera provides the following features:

Best Shot. Keep the best shot from the set of 10 photos.

Action Shot. Show multiple instances of a moving object in a single shot (similar to a feature in the Galaxy S4).

Motion Focus. Visually emphasize a moving object in the shot.

Erase Object. Remove an object from a photo creating a cleaner, distraction-free photo.

Change Face. Pick the best faces in a group shot and create an aggregate photo in which everyone is smiling and no one is blinking.

Smart Camera builds on a previous Nokia app called Smart Shoot but adds more features and has much better fidelity and resolution.  You can even configure the device to access Smart Camera rather than the default Camera app when you tap the hardware camera button.

Smart Camera will be released to other Lumia devices too, which again is hugely important. The 920-class handsets will get the full experience while other Lumias will receive a subset, depending on the capabilities of the device’s camera.

Nokia already makes an amazing array of camera- and photo-related apps, including Cinemagraph (a previous effort to add animations to photos), PhotoBeamer (project photos to any screen), Panorama, Creative Studio (photo editing), Nokia Glam Me (photo effects), and the aforementioned Smart Shoot. They’re all pretty amazing. But with this expansion of the Lumia 92x, Nokia’s reputation for camera excellence is finally starting to match reality. And the camera in the high-end Lumias has indeed emerged as a key advantage for Nokia, one I suspect will be enhanced further with the release of true PureView-based Lumia handsets in the future.