If you want one-time-purchase separation software instead of a yearly plan, Underbase is a Windows option for limited-color art: spot and index separations, a choked white underbase, one-click trapping, and true-size film with registration marks, all offline. Shops whose work is mostly photorealistic art, or that run Macs, should compare Separation Studio and other tools first.
Separations are the step between a customer’s file and a coated screen. For a small shop printing logos on dark shirts, the job is the same every week: one plate per ink, a white base pulled in from the edges, traps where colors meet, and film at true size with marks that line up. The question is whether to pay for that every year or once.
Separate limited-color art, build the underbase, and print film, all on your PC.
Get it from Microsoft
What is the short answer?
Separation Studio NXT is a strong all-round tool, and it is sold as a yearly license. If your work is mostly limited-color logos and type, and you print on Windows 11, Underbase covers spot and index separations, the underbase, trapping, halftones, and film for a one-time price. If you separate a lot of photographic art in simulated process, look at Separation Studio, AI Separations, or QuikSeps, because Underbase does not claim simulated process.
What is Separation Studio known for?
Separation Studio NXT, from Solutions for Screen Printers, is one of the best-known separation programs in the trade, and for many shops it is the strongest all-round choice. According to its own site, it runs on Mac and Windows, offers one-click underbase, choke and spread controls, and sends output to AccuRIP or a RIP hot folder. There is a free trial.
On price, the vendor lists Separation Studio NXT at $229 a year. Its license agreement says the license renews automatically and that the software needs an internet connection to verify the license. That is the part some shops want to avoid: a yearly fee, and a license check that goes online.
What one-time alternatives are there?
Facts about other tools come from their own sites, checked on 17 October 2026. Promotional prices are not listed as regular prices.
| Tool | Price model | Runs offline | Platform | Separation types | Underbase and trapping | Film output |
|---|---|---|---|---|---|---|
| Underbase | One-time purchase in the Microsoft Store, 15-day free trial | Yes, no network connections | Windows 11 version 24H2 or later, x64 | Spot and index | Choked underbase 0 to 3 mm; one-click trapping | True-size film PDF with registration marks; 1-bit TIFFs up to 1440 dpi; production ticket |
| Separation Studio NXT | $229 a year, renews automatically | Needs internet to verify the license | Mac and Windows | Not compared here | One-click underbase; choke and spread | AccuRIP or RIP hot folder |
| AI Separations | $179 one-time | Standalone desktop app | Windows, plus a Mac beta for Apple silicon | Simulated process and spot | Underbase, highlight white, trapping | Not compared here |
| ActionSeps | One-time purchase of Photoshop action sets | Inside Photoshop | Wherever Photoshop runs | Includes simulated process | Not compared here | Through Photoshop |
| QuikSeps Professional | One-time (listed as a promotional deal when we checked) | Inside Photoshop | One copy runs on Mac and Windows | Simulated process, index, spot | Underbase, auto-trap | Through Photoshop |
Sources: Separation Studio NXT, AI Separations, ActionSeps software, QuikSeps.
Underbase
Underbase is a Windows app for limited-color screen printing separations. It opens customer artwork, finds the inks or dithers shaded art between a fitted set of inks, builds a choked white underbase, traps colors, keeps the job inside your plate budget, and writes 1-bit film TIFFs, a true-size film PDF with registration marks, and a production ticket. It runs entirely on your PC, with no account, no upload, no telemetry, and no network connections. Its regular US list price in the Microsoft Store is $99.99, and the listing shows the current price in your currency.
AI Separations
AI Separations is a standalone app, so it does not need Photoshop, at $179 one-time. It runs on Windows, with a Mac beta for Apple silicon, and it does simulated process as well as spot separations, with underbase, highlight white, and trapping. If your work leans toward photographic art, it covers ground Underbase does not. The free trial watermarks exports after the first one. AI Separations also offers a browser tool, which uploads the art, with web credits sold separately.
ActionSeps
ActionSeps sells Photoshop action sets for a one-time fee, including simulated process. If you already own Photoshop and know it well, actions are a familiar route. The catch is that you need Photoshop. ActionSeps’ prices were sale prices when we checked, so see its site for the current figure.
QuikSeps
QuikSeps Professional is also a Photoshop-based tool, and one copy runs on Mac and Windows. It covers simulated process, index, and spot separations, with underbase and auto-trap. Its price was listed as a promotional deal when we checked.
Doing it by hand in Photoshop or Illustrator
Many shops still separate in a design app: selections and channels for each ink, a choked white made by contracting a selection, and hand-placed registration targets. It works, and the skill is valuable. It is also slow for a weekly run of customer logos.
Open a recent dark-shirt order and compare the plates with what went to press.
Get it from Microsoft
How do the prices compare?
Plainly: at its regular US price of $99.99, Underbase costs less than AI Separations’ $179 or one year of Separation Studio NXT at $229. ActionSeps and QuikSeps were showing sale or promotional prices when we checked, so compare them on their own sites on the day you buy. Over three years, Separation Studio is $687 at today’s listed rate, while Underbase and AI Separations are paid once. The Photoshop-based tools also need a Photoshop license, which is a separate cost.
Price is not the whole story. Separation Studio and AI Separations do simulated process, and Underbase does not. If that is your main work, the cheaper tool is the wrong tool.
What does Underbase do, step by step?
- Open. Choose Open artwork, drop a file on the window, or try a bundled sample. Underbase opens PNG, TIFF, JPEG, BMP, GIF, WebP, SVG, PDF, and Illustrator (.ai) files, sizes the print from the file, finds the inks, and opens shaded art in index mode.
- Confirm the inks. In the Inks and plates list, rename, merge, or reorder inks, and turn Print off for the background. Tick UB on the inks that need white beneath them.
- Set the job. Set the underbase choke, trapping, halftone ruling, and dot gain, then the film size, sheet layout, output resolution, and output folder. The plate budget counts every screen as you go.
- Generate. Choose Generate underbase pack (Ctrl+G). The film PDF, 1-bit TIFFs, unscreened channels, production ticket, preview, and job file land in one folder named for the job.
For the methods behind each step, see spot color separations for t-shirts, index separations for screen printing, and halftone film positives.
How do the underbase and trapping controls work?
- Underbase. Turn on Print a white underbase first and tick UB on every ink that needs white beneath it. Dark inks start unticked and print straight on the shirt. Set the choke from 0 to 3 mm in 0.05 mm steps, 0.25 mm by default. The plate can print solid, tinted, or halftoned. Our guide to a white underbase for dark shirts explains why the choke matters.
- Trapping. Spread or choke any ink from -3 to +3 mm in 0.05 mm steps. For the whole job, set Default trap (0.15 mm by default) and choose Apply to all inks, which spreads every ink except the darkest so lighter colors sit under its edge.
- Plate budget. Set Screens available on press, from 1 to 16. Generation waits until the job fits, and Merge inks to fit the budget merges the closest inks in one click.
- Film. Letter through A2 or a custom sheet up to 60 by 120 inches, at 600, 720, 1200, or 1440 dpi, one plate per sheet or ganged, mirrored for emulsion-down output. Print film sends the pages to any Windows printer, and the 1-bit TIFFs go straight to a RIP.
Who should not switch?
- Shops that mostly separate photographic art. Underbase is built for limited-color art with spot and index modes. It does not claim simulated process.
- Mac shops. Underbase runs on Windows only.
- PCs on Windows 10, or Windows 11 older than version 24H2. Underbase needs Windows 11 version 24H2 or later on an x64 PC.
- Shops that rely on a RIP integration such as AccuRIP hot folders. Separation Studio lists that integration. Underbase writes TIFFs you send to a RIP yourself.
Frequently asked questions
What is a cheaper alternative to Separation Studio?
For limited-color work on Windows 11, Underbase is a one-time purchase with a regular US price of $99.99, against Separation Studio NXT’s listed $229 a year. AI Separations ($179 one-time) is an option if you need simulated process.
Is there screen printing separation software that is a one-time purchase?
Yes. Underbase and AI Separations are standalone one-time purchases. ActionSeps and QuikSeps are one-time purchases that run inside Photoshop.
Can I make a choked white underbase without Photoshop?
Yes. Underbase builds the underbase from the inks you tick and chokes it from 0 to 3 mm, with no design app needed.
Does Underbase do simulated process separations?
Underbase does spot and index separations for limited-color art. For simulated process, compare Separation Studio, AI Separations, ActionSeps, or QuikSeps.
What files can Underbase separate?
PNG, TIFF, JPEG, BMP, GIF, WebP, SVG, PDF, and Illustrator (.ai) files.
Does Underbase run on Mac or Windows 10?
No. It needs Windows 11 version 24H2 or later on an x64 PC.
Does customer artwork get uploaded?
No. Underbase has no account, no upload, and no telemetry, and it makes no network connections.
Try it on a job you have already printed
Underbase is a one-time purchase in the Microsoft Store, and the Store runs a 15-day free trial. Open the artwork from a recent dark-shirt order, or one of the six bundled samples, and compare the plates, film, and ticket with what went to press. See our overview of screen printing color separation software, read how to make color separations for screen printing, or go to the Underbase product page.
Try it on a job you have already printed, during the 15-day free trial.
Get it from Microsoft
Separation Studio and AccuRIP are trademarks of their owners. Adobe, Photoshop, and Illustrator are trademarks of Adobe Inc. Microsoft and Windows are trademarks of the Microsoft group of companies. Other product names are trademarks of their owners. Underbase is not affiliated with or endorsed by any of them.
Last updated 17 October 2026. Published by Automata Labs, a software company in Canada.