Difference between Tanning and sun/dust shadow

[arexcrooke]

Anyone want to help me out with it

[Aces]

Telling the difference?

 

Sun/dust-shadow has a straight edge to were it ends (and often is slanted) and affects just one or two sides of the book.

 

Tanning normally goes around all edges and doesn't abruptly end at a straight line.

[Flaming_Telepath]

Telling the difference?

 

Sun/dust-shadow has a straight edge to were it ends (and often is slanted) and affects just one or two sides of the book.

 

Tanning normally goes around all edges and doesn't abruptly end at a straight line.

 

 

..and one is a deterioration of the paper and the other is a blemish from an outside source.

[FFB]

Anyone want to help me out with it

 

I spoke to Tracey Heft about this a few months ago.

 

Sun shadow/oxidation shadow: oxidation of the paper from exposure to light and air. Usually a small, darkened strip on one or more edges of the book. Might be removable or at least minimizable by washing and/or bleaching.

 

Dust shadow: usually occurs on books stored flat in piles. The dust shadow is a darkened strip where part of book was exposed to dust particles as they fell. The dust gets ingrained in the paper fibers, leaving a darkened strip. Can sometimes be dry cleaned away. Washing may set the stain and make it impossible to remove.

 

Tanning: caused by breakdowns in the cellulose chains in paper, which result in increased acidity and a darkening in newsprint and cover stock. Tends be an "all over" thing or at the very least a gradual change from tanned to untanned, with the outer edges of the folio being darker than the interior portions. Often occurs on both sides of the folio, unlike sun shadows and dust shadows, which affect only the exposed side. Usually removable by washing and/or bleaching.

[Jeffreykli]

Clarification question: If there's a definite line, or an abrupt change from white to tan, then that's a sun shadow?

[FFB]

Clarification question: If there's a definite line, or an abrupt change from white to tan, then that's a sun shadow?

 

Unless it's a dust shadow.

[FFB]

Clarification question: If there's a definite line, or an abrupt change from white to tan, then that's a sun shadow?

 

Unless it's a dust shadow.

 

To clarify though, when you look at the book under magnification, you can usually see dirty little flecks of dust amid the fibers when you're looking at a dust shadow, along with some tanning if the book was also exposed to light (so a combined sun/dust shadow). A sun shadow will just be a tan strip.

[Jeffreykli]

Excellent. Thanks; I think I finally understand the difference.

[divad]

Clarification question: If there's a definite line, or an abrupt change from white to tan, then that's a sun shadow?

 

Unless it's a dust shadow.

 

To clarify though, when you look at the book under magnification, you can usually see dirty little flecks of dust amid the fibers when you're looking at a dust shadow, along with some tanning if the book was also exposed to light (so a combined sun/dust shadow). A sun shadow will just be a tan strip.

 

Great stuff Scott In many cases, all three conditions may be present or contributing, as bad storage conditions often result in compound defects.

 

In real life, it is often not one or the other, but both.

[toro]

Does CGC grade lower for one type over the other? I remember some early CGC books came in with high numbers and tanning. But I don't see that as often anymore? Does anyone have a clue on this?

[Sharkey]

Tan:

 

 

Shadow:

[arexcrooke]

[FFB]

Liz took a look at these pictures last night and wanted me to say that based solely on your photos, she greatly prefers tanning to shadows. She was a little tipsy when she said it though, so she's probably going to regret telling me to post that when she sees this.

 

Tan:

 

 

Shadow:

[divad]

Liz took a look at these pictures last night and wanted me to say that based solely on your photos, she greatly prefers tanning to shadows. She was a little tipsy when she said it though, so she's probably going to regret telling me to post that when she sees this.

 

You lovebirds are just too CUTE!

[FFB]

Liz took a look at these pictures last night and wanted me to say that based solely on your photos, she greatly prefers tanning to shadows. She was a little tipsy when she said it though, so she's probably going to regret telling me to post that when she sees this.

 

You lovebirds are just too CUTE!