Some more bumps I encountered along the way ...
To document the size of the stains before and after treatment, I had initially planned to use a programme which Ms Tan recommended - j image, which could project grids over pictures to facilitate the calculation of stained areas. While it was fine for individual pictures that were independent of one another, it was a different matter altogether when comparing the same stains before and after treatment. I could not ensure that the magnifications of the pictures before and after treatment were the exactly the same, and hence directly comparable. I then toyed with the idea of measuring the maximum diameters of each stain before and after treatment, and expressing the difference as a percentage. However, I realised that this would have to be based on the assumption that the stains decreased in size uniformly along their circumferences, which may confound the results if the assumption was not 100% correct. In any scientific investigation, accuracy and precision should not be compromised. Hence, I finally decided to create my own grid, which I did by using a permanent marker to trace an appropriate-sized grid (Amsler Grid Eye Exam) onto a transparency. Using this handy and portable device, it became very convenient for me to place the grid over my stains to calculate the stain area accurately and objectively. Problem solved! :)
The other problem I ran into was the charting of stain colours. The first stain I tried out was the coffee stain. While it was easy to match a colour (using a paint chart) before washing off the stain, it was an uphill task trying to match the residual stain colour after treatment, as most of the coffee stains had become very faint and barely visible, although their shades were still discernible. I resorted to looking at warm make-up colour palettes instead of paint charts, which was slightly more promising, although it did not solve the problem either, due a limited range of colours. Since colour matching is fairly subjective in any case, and the colour before staining was same for all, I am seriously considering ranking the stains after treatment in order of effectiveness, with 0 being 'no stain' seen (identical to control cloth) to 6 being 'stain identical to that before treatment'. I will draw conclusions after adding the scores from both sets of experiments.
As such, I have no conclusive results yet, as I've also decided to 'challenge' my stain removers further by setting the stains for a longer period of time - 3 days!
Watch this space for more exciting developments and trials ... :D
The other problem I ran into was the charting of stain colours. The first stain I tried out was the coffee stain. While it was easy to match a colour (using a paint chart) before washing off the stain, it was an uphill task trying to match the residual stain colour after treatment, as most of the coffee stains had become very faint and barely visible, although their shades were still discernible. I resorted to looking at warm make-up colour palettes instead of paint charts, which was slightly more promising, although it did not solve the problem either, due a limited range of colours. Since colour matching is fairly subjective in any case, and the colour before staining was same for all, I am seriously considering ranking the stains after treatment in order of effectiveness, with 0 being 'no stain' seen (identical to control cloth) to 6 being 'stain identical to that before treatment'. I will draw conclusions after adding the scores from both sets of experiments.
Another minor glitch was the staining of certain substances. I applied all the stains in a similar manner, by dripping 0.2mls of staining agent over the centre of the cloth and allowing the stain to spread slowly on its own. I chose not to rub the stains in, as that would have introduced another variable. It would have been difficult to keep the amount of pressure applied each time constant. Because of this, the chocolate milk that I initially used as my protein stain failed to spread out nicely, as it was too thick and viscous. To obtain a larger stain area, I switched to using Milo drink (Milo powder and water, without added sugar or milk), which worked well. The other staining challenge was oil. I tried olive oil, sesame oil, melted butter, all of which left barely a visible stain after setting! I finally resorted to using laksa oil (YUM!).
Watch this space for more exciting developments and trials ... :D
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