Posted by Vincent Keers on 05-28-2005 08:45 PM:

Digi 2

Dear all,

A test:
I have an original image (color RGB) natural dyed wool.
72 pixels per inch.
I take out 28x32 pixels.
Multiply by 100 so 2800x3200 pixels and change the pixels per inch setting into 9 pixels per inch, because I don't need image sizes like 154 MB.

First image is a light blue synthetic.
At the right lower corner is the same color to the eye, but it's natural indigo, one time dye.

If you have Photoshop you can save the image and try this. If you pick up the eyedropper and move it up and down you'll see that if the eyedropper is on the synthetic blue the marker in the color display stays in the blue part only. If you do the same on the indigo part the marker will jump up and down from yellow to blue and some red.

Next image is cochineal.

Think you can see what part is synthetic and what part is natural. Here the result with the eyedropper is less dramatic, but the natural cochineal has a tendency to show more blue towards purple.

Madder doesn't show any different results.
Madder dyes on very easy, the distribution is very good and even. So the color marker stays in the red part whether synthetic or natural.

These images are taken from wool, at the same distance, same light, same camera and all the wool was on a white background.
The synthetic dyed wool was chosen with the natural dyed wool next to it.

Next is green.

Best regards,
Vincent


Posted by Vincent Keers on 05-28-2005 10:30 PM:

Green....



The natural Indigo/Safran is at the lower corner.
If the eyedropper is used this is the result:
In the synthetic, green is picked up by the eyedropper as maincolor and it goes up and down in the green spectrum.
In the natural, yellow is picked up by the eyedropper as main color and it goes up and down in the green spectrum.

Isn't that a nice result?

I'll try again, with rugs!

Best regards,
Vincent


Posted by Steve Price on 05-30-2005 12:30 AM:

Hi Vincent

The images are interesting, but I don't know what they are or how you got them. I understand that they are greatly magnified - but what were they before you magnified them? For example:
1. Are they direct scans of small pieces of rugs? Digital photos? Scans of photos in books?
2. Is the wool being seen along the sides of the fibers, or from the cut ends of pile?
3. How do you know that the natural dyed images were of wool dyed with natural dyes?

It would be very helpful if you'd post the original images from which the magnifications were made, with some indication of what regions of those images were magnified.

Thanks,

Steve Price


Posted by Vincent Keers on 05-30-2005 11:04 AM:

Hi Steve,

I use the digital camera because the pixels get me inside the color: The combinations of colors (reflected light that builds up a color), that my eyes do not register.
The better the camera, more pixels, the better it will identify the color construction.

1. Are they direct scans of small pieces of rugs? Digital photos? Scans of photos in books?
Digital photos of woolen threads taken from natural colors samples and synthetic color samples. All taken at 30 cm. distance, in jpg format. Each photo 2.2 MB, 72 pixels per inch.
Except the natural green. It's taken from an antique kilim because I don't have the Indigo/safran version of green. Lot of natural greens from different sources, but the natural green we see in the rugs are mostly a yellow/blue version. (This effect can be seen in all kinds of new productions and started my scepticism)

2. Is the wool being seen along the sides of the fibers, or from the cut ends of pile?
Along the sides.

3. How do you know that the natural dyed images were of wool dyed with natural dyes?
Because they are dyed with indigo, madder, cochineal, onion skins, dandelion, eucalyptus, birch bark, sweet chestnut etc.

Hope all do understand I didn't do any previous research.
It's all freethinking, ad hoc and a bit amateurish.

I didn't expect anyone to step forward to tell us how he/she reached a level of perfection in determining the dyes.
Everybody posting on this board doesn't seem to have any problems with synthetic dyes. A huge step forward in my opinion.
The specialists are tumultuously silent.
But, if we count the words "natural dyes" that have entered this board, the net, rugworld during the years, it should makes us wonder what the heck w're talking about.


Best regards,
Vincent


Posted by Steve Price on 05-30-2005 11:11 AM:

Hi Vincent

Thanks for the additional information. One more thing - would you be good enough to put up the images from which you enlarged these little sections? I don't mean that I want to see the 2 MB files, but if you can adjust them to a few hundred pixels in width and, perhaps, 75 kb file sizes, it would be helpful.

Regards

Steve Price


Posted by Vincent Keers on 05-30-2005 12:25 PM:

Hi Steve,






Best regards,
Vincent


Posted by Steve Price on 05-30-2005 12:39 PM:

Hi Vincent

Thanks - that helps. Now, I can see by eye that the colors are more uniform within each thread in the lower series (which, I suspect, is the synthetic dyed wool) than in the upper one (wool from old kilims, right?). This accounts for the nonuniformity of color in the closeups of the old kilim wool, doesn't it?

Clearly, the colors of the wool taken from old kilims is less uniform than that of the unused, synthetically dyed wool. The question is, why? Some possibilities that come to mind:
1. Different nearby spots on a skein of wool dye differently when natural dyes are used, so they are nonuniform. I am hard pressed to think of a physical or chemical reason why this should be so, but can't eliminate the possibility just on that basis.
2. Different nearby spots on a skein of wool dye identically when natural dyes are used. If this is the case, how can we account for the obvious variations that we see?
a. Maybe the old kilims have nearby spots that have faded differently over the long time since the dying was done. This seems reasonable, since the nature of weaving would have nearby areas exposed to light them alternating with areas shielded by being on the back.
b. Maybe normal wear, and exposure to dirt and stains of various kinds accounts for the variations in the old kilim wool.

Are there samples of new wool dyed with natural dyes that can be used for comparison? This would help sort out the possible explanations.

Regards

Steve Price


Posted by Vincent Keers on 05-30-2005 12:40 PM:

Hi again,

This is where I dyed wool.
http://users.skynet.be/wolspinnen

It's all in Dutch, sorry.
The dye mistress has studied it for at least 30 years before she started sharing her knowledge.

Best regards,
Vincent


Posted by Vincent Keers on 05-30-2005 12:43 PM:

Shoot,

No old wool.
All new natural dyed wool. Never uniform.

Best regards,
Vincent


Posted by Steve Price on 05-30-2005 01:50 PM:

Hi Vincent

Thanks. I misunderstood your eaerlier post, thought all the natural dyed wool was from old kilims. Looking back at it, I see that it was only the green.

Regards

Steve Price