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WEB INSPECTION: FAQ's
WHAT IS VIDEO WEB INSPECTION?
Video web inspection is a quality and productivity enhancement tool used on roll-to-roll printing presses to inspect print quality and to "build quality into" the printing process.
In it's simplest form, the device is a visual inspection tool that allows the press operator to see the quality of print being produced by the press, in real time, and in far greater detail than can be seen with the naked eye.
In it's advanced form, the device is both a visual inspection tool and a sophisticated print process management tool, capable of continuous in-line identification of print defects, verification of bar codes, analysis and monitoring of color and even set-up register on Flexo CI presses.
Click here to go to learn more about Print Process Management Systems
Properly implemented, both types of systems will reduce waste, improve press productivity, contribute to higher quality printed product with less effort, improve average press running speed, and contribute to improved customer satisfaction levels.
Basic visual web inspection systems are so common today that any web printing press that does not have such a system on it, is at a substantial competitive disadvantage, and simply cannot produce as efficiently and effectively.
A common strategy for improving the quality, throughput and productivity of older presses, is to outfit them with a proper video web inspection system.
IS VIDEO WEB INSPECTION NEW TECHNOLOGY?
No. video inspection devices for printing and converting applications have been available and commonly used since the early 1990's.
Over the years we have aimed for continuous improvement in the features, technology and value of all our systems. Today's "3000 Series" systems have larger fields of view, better picture quality and color fidelity, and a whole range of new features that make them easier to use and more functional for the operator.
WHAT IS BST'S WORLDWIDE POSITION IN VIDEO WEB INSPECTION?
BST was - and continues to be - a pioneer and leader in both visual inspection systems and Print Process Management Technology. Over the years we have pioneered many, many new products, features, enhancements and technologies to make web inspection easier, faster, more cost effective and more reliable. [click here to visit our Technology Timeline]
Today, we have a complete product line, beginning with our basic POWERScope® 3000 , to our feature rich (and most popular) SUPER HANDYScan® 3000 , to our new 3 Chip PROScan® 3000 model. At the very top of our product line is Premius® Digital 3 Chip – a modular visual inspection AND Print Process Management system all in one.
We introduced our first generation HANDYScan® in 1989, and today we have…..
- over 15,000 visual inspection systems installed in over 75 countries
- over 1,200 Print Process Management Systems that perform automatic defect detection, color monitoring, bar code verification or register pre-setting.
WHAT CAN A VIDEO WEB INSPECTION SYSTEM DO FOR ME?
There are four primary benefits you should expect from your investment in a video web Inspection system: reduced waste, increased productivity, improved quality and greater customer satisfaction.
Because every print operation is unique, so too will be the degree of benefits video inspection produces. The key is to select a system that will optimize your investment, maximize your return on that investment, and provide the greatest benefit within the shortest time.
Waste Reduction
Waste is reduced as a direct result of the operator's ability to immediately see and correct print problems in real time during the run. Print adjustments can be made "on the fly", as the operator spots developing imperfections, tweaks the press and immediately sees the impact. Make-ready should take less time and use less substrate.
- Research shows waste reductions of 20 to 40% are common with some exceptional reductions of 50% or greater. Savings are generated in substrate, inks, coatings, press labor and material handling.
- Customer credits necessitated by poor quality or returns can be eliminated.
- Re-runs due to undetected print problems can be eliminated due to the ability of the operator to see and correct print problems at full press speed.
Increased Productivity
Press room productivity improves not just because waste is lower, but also because press speeds are commonly increased. A video inspection system gives press operators confidence in the quality of product coming off the press. There is no longer a reason to run at slower speeds. As a result, you print more jobs in less time.
- Faster make-ready.
- The ability to continuously scan the entire print repeat gives the press operator confidence in his print quality, and eliminates the need to run at slower speeds.
- Faster press speeds allow you to maximize the quantity of product produced. Faster press speeds of 20% are reported regularly, and 50% increases are not at all uncommon.
- Running at top speeds means you complete more jobs in less time.
Enhanced Quality
Because video inspection allows you to build quality in to every roll you produce, enhanced quality is the third benefit you should expect. Defects will be spotted and corrected faster. Registration will be easier to hold and adjust. Colors can be matched better and monitored for roll-to-roll and job-to-job consistency.
- Image magnification of up to 40 times makes holding and maintaining tight registration much easier. You can also monitor scumming, streaking, hickeys, fill-in, traps, print-to-die registration, bar code quality and a variety of other print defects.
- Split-screen comparisons to a standard facilitate roll-to-roll and job-to-job color comparisons on the fly.
Greater Customer Satisfaction
It is really quite simple; deliver a higher quality product to your customers at the best value and you will improve both customer satisfaction and loyalty (repeat orders).
HOW IMPORTANT IS THE OPERATOR INTERFACE?
Video systems on the market today utilize a variety of different operator interfaces. They combine software (both well written and poorly written) with every imaginable form of hardware - toggle switches, membrane panels with color coded icons, full and miniaturized touch screens and wired or infrared remote controls. There are also systems on the market today that use laptop computers with touch screens or windows-like environments run with a mouse, and even keyboards!
No single characteristic has a greater impact on the overall productivity delivered by a video inspection system (and faster payback) than simplicity of operation. As with any computerized device, all this high tech hardware is only as useful as the software that drives it. It is critical the software be designed from the operator’s perspective. It must be intuitive in its menus and commands and has to be simple to use. A direct correlation exists between how simple a system is to use and how much it is actually used. This is where our systems excel and are far superior to the competition.
WHAT IMPORTANT FEATURES SHOULD YOU LOOK FOR ON A VIDEO WEB INSPECTION SYSTEM?
Click here to go to our Downloads section, where you will find a useful article entitled
" Ten Ways to Use Your Video Web Inspection System to Maximize Press Productivity"
Following are summaries of the most useful features available for visual web inspection.
Field of View
The "field of view" represents the area seen by the camera in each picture. We offer systems with fields of view that range from 4" X 3", 9" X 7" up to 17 ½" X 13".
The size of the field of view versus the size of the average print repeat area (web width times repeat length) is very important. The area covered by a 9" X 7" field of view is more than three times larger than that of a 5" X 4" field of view, and depending upon the application, that is an extremely important consideration. The use of a correctly sized field of view will have a substantial impact on the overall return on investment from the system.
An even smarter solution is to use a system with our unique Virtual Repeat® Technology
Virtual Repeat® Technology
Unique technology pioneered by BST five years ago allows the operator to see the entire print repeat area, regardless of web width and repeat length. It also greatly simplifies movement around the repeat, saving valuable time for the operator. Virtual Repeat Technology is available for the first time ever on a visual inspection system, on our new PROScan® 3000.
Motorized Traverse & Lens Operation
Motorizing the camera movement along the traverse allows the system to perform additional high value tasks for the operator with little effort and usually at a very reasonable additional cost. We recommend the use of motorized traversed for webs 10" or greater. The additional value far exceeds the additional cost.
Quick Zoom
Imagine if your press operator could save just five seconds ever ten minutes. Over the course of a year, he would have saved 73 hours. Those are 73 hours that could be spent on higher priority tasks.
At BST, we believe that it is more important for a press operator to run their press, rather than another piece of equipment, such as the inspection system. So we go to painstaking effort to put functional, time saving features on all our inspection systems. Features like Quick Zoom, which will easily save your operator 73 hours a year. Features that you will not find on other inspection systems.
Auto Constant Scan (ACS)
This software, in combination with a motorized traverse, allows the camera to automatically "walk" in both the lateral and linear direction, allowing repeated inspection of 100% of the plate area, over time. The press operator should be able to control the size of the steps in both directions and the time between each new image. The more sophisticated systems on the market have a "100% Scan" feature that does all of this automatically. By using a larger field of view, the time required to inspect the entire repeat area can be greatly reduced.
ACS is probable the most useful function you can have on any video inspection system.
Positional Memory
Positional Memory allows the operator to select specific locations on the web for repeated inspection. The better systems allow you to program custom inspection routines virtually in seconds, and then execute those routines with the push of a single button. Our new PROScan® 3000 even has an "Image Gallery" that makes it possible to review and move about a large quantity of critical print areas in just seconds.
Positional Memory is used for monitoring critical spots on the web, such as registration marks, logos, color traps, bar codes, print to die registration, critical process print areas and any area of critical print.
Split Screen
Split Screen functions provide for on-screen comparisons of two or more images; generally one being a previously stored standard and the other being images of the live web. Split Screen is very useful for color comparisons, and has proven to be particularly effective for make-ready.
Our new SUPER HANDYScan® 3000 and PROScan® 3000 systems have split screen that can be moved anywhere on the repeat, and can be sized both horizontally and vertically.
Remote Operator Control Panels
Remote Operator Control panels allow the system to be operated from any location press side, or to be run from multiple locations. They are ideal for longer presses, or for larger machines with web blind spots, or where access to the video system would help run the press, such as near the CI drum on a Flexo CI press.
CAN I SEE THE WHOLE REPEAT?
About five years ago, BST pioneered Virtual Repeat® Technology, for the first time ever allowing a video inspection system to see the entire repeat. What a major achievement it was! We now offer Virtual Repeat® Technology on our Premius® Digital 3 ChipPrint Management System and on our PROScan® 3000 visual system.
Most visual inspection systems today have another feature we pioneered in 1989, known as Automatic Constant Scan (ACS). This allows the camera to move across the web and around the repeat automatically, a very simple and yet effective means for inspecting the entire repeat cost effectively. Today our systems do this automatically, at the touch of a single button.
WHAT ABOUT ANALOG VERSUS DIGITAL CAMERAS FOR VISUAL INSPECTION?
Our Research and Development department has evaluated hundreds of digital cameras, and in our opinion there is not yet a digital camera made that is suitable for visual inspection systems.
Oh yes, there are plenty of low cost digital cameras on the market – our competition uses them – but image resolution, color fidelity, contrast, white balance…you name it…..not one of the critical quality attributes of the lower cost digital cameras currently available has a quality that is acceptable for use on print inspection devices.
Digital camera technology does offer real advantages, but this requires the use of a higher end, higher quality and of course, more expensive cameras.
Click here to go to learn more about Print Process Management Systems
WHAT ARE THE USES AND ADVANTAGES OF 3-CHIP CAMERAS?
Generally speaking, the larger the size of the image area seen, the greater the need for higher resolution. As a general rule, if you are viewing an image area larger than 7 or 8 inches in either direction, you will benefit greatly from a higher resolution camera. Also, if you are printing 6-point type or smaller, monitoring bar code quality, or doing a great deal of process printing will also benefit from high-resolution cameras.
Three-chip (3CCD) cameras provide substantially better resolution that will benefit many applications. The impact upon color is most noticeable for process work, vignettes and for critical colors. Tonal quality and hue is better with a three-chip camera than a single-chip cameras.
For applications doing only line and screen work, laying down areas of uniform solid color, the three-chip camera will not make a significant difference versus the additional cost.
WHY ARE XENON STROBES USED IN VIDEO WEB INSPECTION SYSTEMS?
Xenon strobes provide what the engineers refer to as the "flattest spectral output," which means they deliver uniform light over a wide range of colors. Xenon strobes are also known to produce the best color balance (consistency from flash to flash), and generate short duration high intensity light, which is crucial at high magnification levels and with the short focal length lenses used in video inspection systems. Circumferential strobes should be avoided as they produce hot spots on varnished, UV coated or any reflective substrate.
AREN'T ALL ELECTRONICS IN VIDEO SYSTEMS THE SAME?
Nothing could be further from the truth. There are different quality levels of electronics just as there are for any product or product component. There is industrial strength quality and there is consumer grade quality, and a cost associated with the difference. In electronic goods, these differences can mean large variations in the quality and reliability of the electronic components. Where are the boards made and what is the skill level of the work force that made them? Are the boards hand soldered or machine "stuffed"? Are the electronic components surface mounted? All these things greatly impact reliability and durability, and should be high on your list of requirements. Obviously, the construction and quality level of the system will affect maintenance and service, and with electronic devices it is real easy to drop some serious dollars on service or repairs.
Built in static and surge protection devices are another important feature. We put internal components on all our equipment to help control and minimize electronic static discharge (ESD) and voltage surge, and to prevent any impact on the electronics. This adds another level of reliability to our systems that you do not find on many competitive systems.
Field testing has documented the value to the converting industry of custom engineered electronics, heavy duty protective housings, high capacity fans, and static and surge protection in a video inspection system. Such systems have repeatedly been found to be significantly more reliable in the press room - requiring less repairs, less often. Video inspection systems that are essentially consumer grade PC's have been found to be far less reliable in the press room environment. Over time, the cumulative effects of static, moisture, heat and dust (the worst enemy of a personal computer) are just too much.
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