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Problem statement

The ability to image sketches hidden by layers of paint is a valuable asset to art purchasers in their attempts toexhaustively examine the works they collect. Art conservators value a painting's underdrawings for two main reasons. The firstis that underdrawings can be exploited as an aid in determining whether the painting is an original or a forgery, by comparingthe style of the underdrawings to those of an artist's other works. The second is that comparisons between a painting and itsown underdrawing can give new insights into an artist's creative process for that work of art. Underdrawing images are bestrevealed by near infrared (NIR) cameras because all paint pigments, except black, are somewhat transparent in the 900 - 1700 nm range . However, current NIR cameras that are sensitive in this wavelength range are exorbitantlyexpensive, typically costing around $50,000 . This leaves the market of small art museums and individual artcollectors unaddressed. We intend to deliver an NIR camera that meets or exceeds key imaging system parameters in this market,such as spectral range, image resolution, capture time, and portability, while also reducing cost below the $5,000 level.

Background

Before the 1960s, there was only one way to examine a painting's underdrawing: the layers of paint in front of the underdrawing had tobe removed, thereby destroying the painting in the process. This was unacceptable for multiple reasons. Since underdrawings are typicallyof less interest than the finished painting, removing the layers of paint on top is not justified. Also, many interesting results comefrom a detailed comparison between the original painting and its underdrawing. This comparison is difficult if the paint layers mustbe destroyed to access the underdrawing.

J. R. J. van Asperen de Boer was the first to image underdrawings using NIR reflectography in 1968 . Previous attempts had used an NIR camera to passively capture light inthat range. However, with passive capture it was difficult to see through pigments such as green, since most of the lightcollected was in the range of 750 - 900 nm, which is below the range where those colors are transparent. Boer solved thisproblem by capturing the reflected light from a tungsten lamp that produced radiation of wavelengths up to 2500 nm, giving amuch clearer image of the underdrawing. While Boer's design has been improved in numerous ways during the past four decades, itremains fundamental to most techniques for imaging underdrawings nondestructively.

and below are examples of comparisons between original paintings and their underdrawings ascaptured with a typical modern NIR camera. In , the underdrawing shows that the man in the top hat, the artist'saccountant, was initially looking towards the viewer, but later this changed so that he looked away, purportedly because ofdisagreements between the two men . In , a large arrow can be seen on the chest of a horse on the underdrawing of a painting by Laib. This arrow is absentfrom the overlaid painted image.

Questions & Answers

can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
is it 3×y ?
Joan Reply
J, combine like terms 7x-4y
Bridget Reply
im not good at math so would this help me
Rachael Reply
yes
Asali
I'm not good at math so would you help me
Samantha
what is the problem that i will help you to self with?
Asali
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Nir single pixel camera. OpenStax CNX. Apr 29, 2008 Download for free at http://cnx.org/content/col10525/1.1
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