Though DNG is not on their list of 'acceptable filetypes'.
• Acceptable file formats for color or grayscale bitmapped images, grouped in order of preference.
1.
TIFF_UNC (TIFF, Uncompressed Bitmap) in any color space supported by TIFF
TIFF_UNC_EXIF (TIFF Uncompressed File with Exif metadata) for images from digital cameras
TIFF/EP (TIFF/EP, for Electronic Photography) for images from digital cameras
\JP2_J2K_C_LL (JPEG 2000 Part 1 Core Coding, Lossless Compression) in
JPX_FF (JPEG 2000 Part 2 [Extensions] jpx File Format), conforming to capabilities of a baseline JPX reader
JP2_J2K_C_LL (JPEG 2000 Part 1 Core Coding, Lossless Compression) in
JP2_FF (JPEG 2000 Part 1 [Core] jp2 File Format)
TIFF/IT (TIFF/IT, for Image Technology) for prepress images
2.
JP2_J2K_C_LSY (JPEG 2000 Part 1 Core Coding, Lossy Compression) in
JPX_FF (JPEG 2000 Part 2 [Extensions] jpx File Format), conforming to capabilities of a baseline JPX reader
JP2_J2K_C_LSY (JPEG 2000 Part 1 Core Coding, Lossy Compression) in
JP2_FF (JPEG 2000 Part 1 [Core] jp2 File Format)
3.
PDF/A (PDF for Long-term Preservation)
PDF/X (PDF for Graphics Exchange)
JPEG_DCT_BL (JPEG DCT Encoding, Baseline), lossy compression in
JFIF (JFIF JPEG File Interchange Format)
4.
PNG (Portable Network Graphics Format)
5.
GIF (GIF Graphics Interchange Format, version 89a)
6.
BMP file (Microsoft Windows Bitmap Format)