DigiGrade
DIGIGRADE - A software application specifically designed for textile Colour Fastness Grading.
“We believe DigiEye DigiGrade to be the future of colour fastness grading – it’s objective, accurate and enables fast, confident decision making.”
Phil Patterson Dyeing, Finishing and Colour Manager. Marks and Spencer-August 2006
COLOUR FASTNESS
Colour Fastness is a measure of how permanent a colour is on fabric. Colour can be adversely affected by a number of factors including exposure to light, to water as in washing and to normal wear and tear such as rubbing against a surface.
Various test methods have been created to assess how the colour is affected by these different parameters and a numerical value is then established to indicate the degree of colour change. read more……..
Colour Fastness grading for both change of shade and staining of control fabric has traditionally been undertaken by trained and experienced graders using a VeriVide standard illumination cabinet and a set of greyscales.
Now this has changed!
VeriVide’s DigiEye system with the DigiGrade application can grade these colour fastness test samples digitally, by the use of a digital camera giving objective, accurate, speedy results.
BENEFITS
The benefits over visual techniques are:
- Reliable, Repeatable and Reproducible - supplying unequivocal data.
- Ambiguity and subjectiveness removed - leading to speedy agreement of claims.
- Quicker - enabling reduced time to market and less costs.
- Increased laboratory throughput – experienced staff used for the testing not the grading.
- Expert training provided - in less than half a day your staff can be trained.
- The images and results can be sent electronically saving shipping of samples.
Please Note: Some retailers and test houses do not accept digital grades so you should check with your customer before submitting results in this form.
Colour Fastness Grading
Martyn Jennings, Senior Colourist at NEXT is impressed by the speed of DigiGrade in comparison with manual grading.
Unlike manual fastness grading, Colour Fastness grading using DigiGrade can be undertaken with minimal training allowing the laboratory team to utilize their skills elsewhere. At present DigiEye is used by NEXT for fastness grading by exception, to provide definitive, quantifiable and indisputable answers to specific quality issues that arise.
HOW IT WORKS
The DigiGrade Colour Fastness feature within DigiEye is used to evaluate change of the shade and the staining using captured images of treated sample and adjacent multi-fibre test fabric. As can be seen in the example on the right from NEXT plc.
The equations used for assessing both staining and Change of Shade are those proposed for the new ISO Standard for the Determination of colour fastness grades by digital imaging techniques, ISO 105 A11.
- DigiGrade correlates the colour difference between the tested and reference samples compared to actual historical visual assessments of experienced trained colour assessors.
- By adopting this method DigiGrade is independent of the type of multi-fibre or greyscale used, thus making it suitable to grade ISO, AATCC and JIS test methods and samples reliably.
- When evaluating Colour Fastness with DigiGrade it is important to mount the control fabrics and the treated samples together for imaging in the DigiEye system in order that the imaging and measurement conditions are identical.
- An additional benefit of imaging the two together is that the DigiGrade software can calculate the degree of staining and change of shade quickly and easily as all the information is available on the monitor at the same time, the assessment can be performed both manually and automatically against the A04/A05 grey scales.
The results can be reported in the standard greyscale format e.g. 4-5, 4, 3-4, 3 etc or as digital grades e.g. 3.25. Marks and Spencer offer an incentive allowing a 0.25 concession for selected tests for suppliers to use DigiGrade and report the results as digital grades, they will accept 3.75 instead of grade 4 and 3.25 instead of grade 3-4.
The relaxed tolerance does not put merchandise at risk as the DigiGrade software is considered to be far more reliable than a human eye.
Please Note: If you intend to use DigiGrade results for UK high street retailers, you will need a copy of their test method for digital assessment or a UKAS or equivalent accredited method.
MULTIPLE APPLICATIONS
The DigiGrade Colour Fastness feature is most commonly used to evaluate wash fastness results, however, it is also capable of evaluating the following tests: -
- Crocking (dry and wet rubbing).
- Determining grade 4 endpoint for light fastness.
- Assessing large printed examples for Change of Shade.
The default operation of Manual Grading assumes that each test will consist of one or more Change of Shade assessments and its corresponding multi-fibre test fabric. However, it is possible to assess and report change of shade only on individual adjacent fabrics by simply selecting the required samples.
Patterns and accessories can be as easily graded as plain fabric, the selection tool can be changed to collect data from very small areas so change of shade can be determined for all the main colours in a weave. This enables judgement to be made on an area, which is too small for accurate and timely visual assessment, giving the benefit of being able to report on individual yarns if remedial action is required.
NEW FOR 2007 – THE MULTI-FIBRE SELECTION TOOL
A special selection tool is available for selecting all of the fibre components of a multi-fibre strip in one operation; this is the Multi-fibre Selection Tool. Rather than having to manually select the individual fibres the tool will automatically select a test region on each of the multi-fibre components on a multi-fibre strip. This is more efficient and saves time over the original method.
To use the Multi-fibre Selection Tool simply drag out a rectangle on the reference multi-fibre strip starting at the Acetate selvage and ending on the wool selvage. The software will automatically determine where the selection rectangle for each test fibre should go, repeat the selection for the tested specimen. The result for each fibre in the multi-fibre strip will appear in the results grid, as illustrated in the images below. It’s as easy as that!
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WISH TO KNOW MORE?
Further details of the DigiEye System - including the Large Area Imaging (LAI), are available via the Datasheet below (click on the relevant links to download or open).
Alternatively please contact Gary Atkins - Sales Manager to arrange a demonstration.
| DIGIEYE DATASHEET | LAI - DATASHEET | |
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| DOWNLOAD PDF | DOWNLOAD PDF |