# Negative Space Web Guiding - Using the Negative Space in your Print > Line guiding is one of the subsets of contrast sensing applications. It requires the printing of a line on a web. It's purpose is to provide a feature that a sensor can track to determine the web position. The typical use is in web converting where guiding on the edge might not be a precise param... **Last updated:** 2021-07-29 **Source:** https://live-roll2roll.pantheonsite.io/blog/negative-space-web-guiding-using-negative-space-your-print --- ## Line guiding is one of the subsets of contrast sensing applications. It requires the printing of a line on a web. It's purpose is to provide a feature that a sensor can track to determine the web position. The typical use is in web converting where guiding on the edge might not be a precise parameter in printing labels. However, printing a line is an additional cost. After all, it is additional ink. If the line is printed outside of the main printed features of the web, it could be leaving money in the converting floor in the form of excess trim on the edges of the web. This is particularly expensive in labels printed on foil, a costlier material than paper. Here is where using the negative space in the print could be a solution to reduce costs in your printing operation. ## Negative Spaces  Negative space is the background or the area that surrounds the subject of the work. Labels are printed features on a web. The background is considered the negative space. In many cases the negative space is a constant color or hue. In these cases where the background color has no degradation or changes in color, contrast detection can be used for a Negative Space Web Guiding ## Negative Space Web Guiding  A desired condition for contrast detection is a feature that is constant in width and in color tone. Line tracking is such and application. If the line maintains the color tone and its width, it is easily tracked. Line guiding is based on that. The same can be applied in using a negative space as a feature to track. If the negative space is of constant width and color tone, then it can be used as feature to track, and therefore can be used as negative space web guiding. That is easy when the space is constant. What if the feature is intermittent? ![Contrast Tracking with Intermittent Negative Space](https://r2r.tech/sites/default/files/inline-images/ARIS-WPS-WL-48-Contrast-Sensing.png) > #### You really do not need to add a printed line to your roll of labels to track the position of the labels. Negative Space Web Guiding is an interesting solution to eliminate line printing for web guiding. Negative Space Web Guiding is a solution to this. However, intermittent negative spaces can be an issue for accurate and precise web guiding. Well, we have a way of treating with intermittent negative spaces. Our technology allows our contrast sensors and our line of single dimension cameras to give you a solution that allows many applications using negative spaces, including when they are intermittent.  Our next blog will explain some of these applications and how they can help your operation deal with interesting ways of using negative spaces. [Contact us for more information on web guiding and monitor applications](https://r2r.tech/contact). ## Related Products - Web Position Sensor - Web Guides - Web Guide Controller **Tags:** Web Position Sensor, Web Guides, Web Guide Controller --- ## About Roll-2-Roll Technologies Roll-2-Roll Technologies designs and manufactures patented fiber-optic web position sensors and advanced web guiding controllers — the precision measurement and control core of modern roll-to-roll manufacturing. Spun out of Oklahoma State University's Web Handling Research Center and trusted by Fortune 500 medical, battery, and nonwovens manufacturers, our patented sensors work without recalibration at ±0.1mm accuracy up to 760 mpm — typical customer outcomes are 50%+ less downtime and payback under six months. Headquartered in Stillwater, Oklahoma, our team of PhDs, controls engineers, and industry veterans extends the sensor + controller core into complete web guide systems including stepper-motor-based linear actuators (RLA, BLA, LHS). - Website: https://r2r.tech - Phone: +1 (888) 290-3215 - Email: sales@r2r.tech