A DNG can hold more than one image representation
A camera DNG may contain both Bayer mosaic sensor samples and an embedded JPEG preview for quick viewing. The preview is already rendered for display; it is not the full Bayer sensor data. Its dimensions and bit depth can be much lower than the original capture.
Some software can show the embedded image before it has decoded the sensor data. Microsoft's Windows codec table lists embedded non-RAW DNG previews, but codec availability and setup depend on the Windows version and device. An image appearing on screen alone is not evidence of a full-resolution RAW decode.
A file opening successfully does not show which representation supplied the pixels; check decoder details after import.
What full sensor processing means
When original DNG decoding succeeds, the app unpacks supported sensor samples and demosaics Bayer data into full-color RGB. The import details report the decoded image's actual dimensions and source depth. Compare the imported dimensions with the expected size of your camera original.
Demosaicing estimates color at each output pixel from neighboring sensor samples. It does not mean the camera recorded three full-color values at every Bayer location. The output is a full-size color image built from the sensor mosaic.
RAW decoding keeps the precision available in the supported source and processing path. It cannot recover sensor channels that were fully saturated at capture.
Inspect the import details
After importing, select the DNG source and check its dimensions, bit depth, and decode status. Compare those numbers with the camera file's expected sensor size when you know it. Dimensions or 8-bit depth far below the camera's sensor specification can indicate that the app used preview pixels.
In this app, an original DNG decode failure may use a usable embedded preview as an explicit fallback. The source is marked as a preview fallback, reports the preview's real dimensions and depth, and shows an orange warning. That warning persists through export and cache restore.
If there is no valid preview, or decoding is cancelled, the failure or cancellation remains visible. The app does not silently treat a preview as full-resolution RAW.
A higher-bit-depth export cannot upgrade a preview
Saving preview pixels to Float32 DNG or 16-bit TIFF changes the output container, not the source information. It cannot recreate the missing Bayer samples, restore original sensor dimensions, or recover detail lost when the preview was rendered.
The same is true for an 8-bit JPEG source. A higher-depth export can reduce additional quantization in later edits, but it does not retroactively add input precision.
Read the Float32 DNG and TIFF comparison to choose an output for the next editing step. For an overview of sharing and editing formats, see panorama JPEG, PNG, TIFF, and DNG.
Checking DNG input in Microsoft ICE
If an ICE panorama made from DNG files has fewer pixels or less highlight detail than expected, check the decoded source before blaming the export format. A preview-based decode is one possible explanation: the preview may already have been resized, sharpened, and rendered into a smaller tonal range.
Microsoft's built-in DNG codec is documented around embedded non-RAW previews. Additional codecs and Windows configurations can change the input path, so this does not establish what every ICE installation uses. Compare imported dimensions and a bright patch with a sensor-decoded version of the same original. Changing the output container cannot restore information lost before stitching.
Keep the originals and verify the result
Keep the camera DNGs after import. They are the source material for another decode or a revised stitch. A saved preview or stitched panorama cannot replace the original sensor data.
For one concrete example of import and export, see the Microsoft ICE alternative guide. Its workflow and limitations are separate from the question of whether a particular DNG source decoded from sensor data or its preview.