Image MIME Reference
DGN
MicroStation Design File
image/x-vnd.dgn
VS
Adobe Photoshop Document
image/vnd.adobe.photoshop
PSD
A complete technical comparison of MicroStation Design File and Adobe Photoshop Document — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | DGN | PSD |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | ✕ No | Yes |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | ✕ No | Yes |
MicroStation Design File
image/x-vnd.dgn
Extension
.dgn
Container
Microsoft OLE Compound File (V8) / IGDS (V7)
Compression
Uncompressed / OLE Structured Storage
Algorithm
None
Color Depth
Indexed Color (V7), 24-bit True Color (V8)
Developed by
Intergraph (Originally) / Bentley Systems (Currently)
Released
1980
Magic Bytes
D0 CF 11 E0 A1 B1 1A E1 (For V8 DGN)
Adobe Photoshop Document
image/vnd.adobe.photoshop
Extension
.psd.psb.pdd
Container
Adobe Photoshop Document (PSD/PSB)
Compression
Uncompressed / RLE (Run-Length Encoding) / ZIP
Algorithm
RLEZIP (with or without prediction)None
Color Depth
1-bit (Bitmap), 8-bit, 16-bit, 32-bit (Float/HDR)
Developed by
Adobe Systems
Released
1990
Magic Bytes
38 42 50 53
Browser Support Comparison
| Browser | DGN | PSD |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
DGN
DGN Strengths
- Exceptionally robust at handling massive, coordinate-heavy infrastructure models that would frequently crash older versions of competing CAD software
- Deeply entrenched as the absolute standard format for many global departments of transportation and civil engineering firms
- V8 architecture supports boundless design plane coordinates, eliminating the physical scaling limitations of V7
Limitations
- Deeply proprietary format requiring complex third-party libraries (like the ODA SDK) to parse or write programmatically outside of the Bentley ecosystem
- V8's reliance on the archaic Microsoft OLE Compound File container makes file introspection cumbersome
- Cannot be rendered natively in web browsers without converting to WebGL/Canvas formats or SVG
PSD
PSD Strengths
- The undisputed global standard for layered raster graphics and non-destructive image editing
- Supports incredibly complex compositions combining raster data, vector shapes, live text, and adjustment layers
- Full support for advanced color spaces (CMYK, Lab, multi-channel) and 32-bit floating-point HDR workflows
Limitations
- Proprietary format: while the specification is published, complete feature-parity is rarely achieved by third-party software (e.g., smart objects and complex layer styles often break)
- Files can reach enormous sizes (gigabytes) due to the preservation of unflattened, high-resolution layer data
- Zero support for native rendering in web browsers or standard mobile image viewers
When to choose which format
DGN
Use DGN when…
- Civil Engineering and Plant Design
- Large-scale Architecture and Construction (AEC)
- 2D/3D Infrastructure Modeling
PSD
Use PSD when…
- Professional Photo Retouching
- Digital Painting and Illustration
- UI/UX Design Workflows
- Graphic Design and Print Production