- Export DTF artwork as a PNG at 300 DPI or higher, since a JPEG cannot hold transparency and prints a white box.
- Do not add your own white underbase or background, because our RIP software creates the right white layer.
- Convert fonts to outlines before sending vector files, or the font may be swapped for a default one in production.
- Size artwork for print, not screen: a 12 inch wide design needs about 3600 pixels at 300 DPI to stay sharp.
Most DTF print problems are solved before the job ever hits the printer. Here are the five file errors we see every week, and exactly how to avoid them.
5
File Errors Covered
300
Min DPI Required
100%
Preventable Reprints
DTF transfers deliver incredible color range, soft hand feel, and work on virtually any fabric. But all of that potential gets wasted when the file going into the printer is wrong from the start. We've seen it hundreds of times: a great design, a bad file, a ruined transfer.
These five mistakes aren't obscure. They come up constantly. Here's what they are, why they happen, and exactly what to do instead.
01 Wrong Color Mode: CMYK Instead of RGB
Most Common Mistake
This is the single most frequent problem we see on submitted files. A designer builds artwork in Adobe Illustrator or InDesign, saves as CMYK because that's standard for offset or screen print, and the colors look completely different once the transfer prints.
Why it happens: CMYK is the correct color space for traditional print methods. It's what most professional designers default to. But DTF printers are RGB-native devices. The RIP software that drives the printer expects RGB data. When it receives a CMYK file, it runs a conversion that almost always shifts colors, especially saturated blues, vivid oranges, and neon tones.
What It Looks Like
Bright reds going muddy. Electric blues becoming flat. Neon greens printing as olive. The design isn't wrong: the color translation layer is adding an unwanted middleman to the process.
RGB vs CMYK: DTF Color Impact
Visual drift when CMYK is used instead of RGB for DTF output
The Fix
Always build and save your DTF files in RGB color mode. In Illustrator: File → Document Color Mode → RGB Color. In Photoshop: Image → Mode → RGB Color. If you're handing off a file from another designer, ask them to convert before sending.
Arnold Prints Tip: If your design was built in CMYK, don't just change the color mode: you may need to re-sample your swatches. CMYK-to-RGB conversion at the document level doesn't always recalculate embedded color values. Do a hard check on any particularly saturated colors after converting.
02 Low Resolution: Insufficient DPI at Print Size
Shows Up After Transfer
You can't see this mistake on screen. Most monitors render at 72 to 96 PPI, so a 150 DPI file looks perfectly sharp until it's pressed onto fabric and you're reading text from six inches away.
Why it happens: Designers size artwork for screen, not print. A logo that's 500px × 500px looks fine on a product mockup site but only prints at ~1.7 inches before it starts pixelating. The math is simple: pixel dimension ÷ DPI = print inches.
DPI vs Print Size: Usable Output Width
Usable print inches at each DPI for a 1000px wide file
The Fix
Set your document to 300 DPI at actual print dimensions before you start designing. A 12" × 12" design at 300 DPI needs to be 3600px × 3600px. If you're scaling up an existing logo, contact us: we can assess if a vector conversion is needed.
Pro Tip: Always work in vector (AI or EPS) when possible. Vector files are resolution-independent: you can output them at any size without quality loss. When you rasterize for export, choose 300 DPI or higher.
03 Wrong File Format: Sending JPEG Instead of PNG
Kills Transparency
JPEG was designed for photographs. It uses lossy compression and has no transparency channel. Any part of your design that should be invisible (the area around a logo, internal cut-outs, soft gradients fading to nothing) will print as a white box or blocky artifact.
PNG
Best Choice
Lossless, full alpha transparency, 300 DPI support. Gold standard for DTF.
Great for Vectors
Vector-based, sharp at any size. Ideal when fonts are outlined.
PSD
Acceptable
Good if layered. Flatten and confirm color mode before sending.
JPG
Avoid for DTF
No transparency. Lossy compression adds artifacts on hard edges.
The Fix
Export your final artwork as a PNG at 300 DPI. In Photoshop: File → Export → Export As → PNG, Resolution 300. In Illustrator: File → Export → Export As → PNG, Resolution 300 PPI, Anti-Aliasing: Art Optimized.
Watch Out: Some design tools let you "save as PNG" while silently flattening transparency against white. Always double-check in a preview with a dark background: you'll immediately see any white halo or fill that shouldn't be there.
04 Manually Adding a White Underbase Layer
Creates Print Artifacts
DTF transfers require a white ink underbase to make colors pop on dark garments. This is true. But you should not add it manually to your file. We do it automatically through our RIP software, calculated precisely per-pixel based on your design.
When a customer manually adds a white layer, usually a big white rectangle or a slightly expanded offset of the design, the result is a visible white border or halo that shows on the finished garment. It can't be removed after printing.
| Approach | Result on Garment | Use This? |
|---|---|---|
| Clean PNG with transparency, no white layer | RIP adds correct per-pixel white base automatically | Yes |
| Manually placed white rectangle behind design | Hard white border visible on garment | Never |
| Design expanded with white offset layer | White halo artifact around entire design | Never |
| PNG exported without white, full transparency | Clean edge, professional result, correct base | Yes |
The Fix
Send us a clean PNG with proper transparency: no white fill, no white background. Our RIP software calculates the exact white underbase needed. You get cleaner edges and better color saturation than any manual white layer could produce.
Exception: If your design intentionally has a white element as part of the artwork (white text, white graphic), that's fine: those areas should be white in your file. The rule applies only to backgrounds and underbase layers.
05 Not Outlining Your Fonts
Font Substitution Changes Your Design
Live text in a vector file requires the font to be installed on the machine that opens it. When you send an Illustrator AI or EPS file with unoutlined text, our production system attempts to open it, and if the font isn't installed, it substitutes whatever default font is available. Your custom typeface becomes Arial. Your hand-lettered logo becomes Times New Roman.
1
Select all text in your design
: use Edit → Select All, or manually select each text element.
2
Convert to outlines
: in Illustrator:
Type → Create Outlines(Shift+Ctrl+O / Shift+Cmd+O).
3
Save a backup of the original
: outlined text is no longer editable. Keep a layered version with live text for future revisions.
4
Verify visually
: zoom in to 300%+ and confirm letter shapes, spacing, and any custom tracked/kerned text still looks correct.
5
Export or save as PDF/PNG
: outlined art exports cleanly to either format with zero font dependencies.
The Fix
Always convert text to outlines/curves before sending production files. If you're not sure how to outline fonts, send us a high-resolution PNG instead: the text is already rasterized and the font issue disappears entirely.
Alternative: If you're working in Photoshop, text is already rasterized on export: this specifically applies to vector-based files from Illustrator, CorelDRAW, Affinity Designer, and similar tools.
DTF File Prep Checklist: Send It Right the First Time
Color mode is RGB
- : not CMYK, not Grayscale
Resolution is 300 DPI minimum
- at actual print dimensions
File format is PNG or PDF
- : not JPEG
Transparency is clean
: no white fill, no white background, no manually added underbase
Fonts are outlined / converted to curves
- , or file is a rasterized PNG
Size is specified
: include print dimensions in your order notes (e.g., "Print at 4" wide")
Background is transparent
: verify on a dark-colored background before sending
Common Questions
Frequently Asked Questions
What color mode should I use for DTF files?
Always use RGB color mode for DTF printing. DTF printers are RGB-native devices: CMYK files look accurate on screen but print dull and desaturated because the printer converts them through an extra layer of translation.
What DPI do I need for DTF transfers?
300 DPI at print size is the minimum for quality DTF output. For photorealistic artwork, 300 to 360 DPI is ideal. Anything below 200 DPI at print size will show visible pixelation once transferred onto fabric.
What file format is best for DTF printing?
PNG is the gold standard for DTF. It preserves true transparency, supports 300 DPI, and uses lossless compression. Never send JPEG for any design with a transparent or custom background.
Do I need to add a white base layer to my DTF file?
No. Arnold Prints adds the white underbase automatically as part of our RIP software process. Just provide a clean file with proper transparency. Do not add white manually unless specifically asked.
Should I outline my fonts before sending a DTF file?
Yes. Always convert text to outlines or curves before saving and sending. If you send a file with live text, any font not installed on the production system will substitute, changing your design layout and letter shapes.
