Changes In Hue Research Articles

Chromaticity of Gromwell, Cape jasmine Dyeing, and Effects of Zinc Oxide/Polyphenol Treatment with Copper Mordanting for UV Protection

To protect skin from harmful ultraviolet (UV) radiation, there has been a resurgence in the use of natural dyes with metal mordants to reduce contamination by advanced chemicals. This study achieved natural dyeing in violet and yellow colors from Gromwell red roots and Cape jasmine seeds for UV-protective materials. The dyed fabrics were subjected to zinc oxide (ZnO) and polyphenol treatments, as well as copper post-mordanting. The SEM, TEM, and XRD tests showed that the ZnO nanoparticles, with hexagonal crystal structures, stuck to the fiber surfaces, and twisted strands resulted in the K/S reduction. First, this study found that the untreated cotton in violet, despite the highest K/S, faded the most intensely when exposed to UV. The color variation of untreated polyester was narrow, with little change in L, a*, and K/S. The color change of yellow-dyed samples treated with ZnO/polyphenol was not considerable in yellowness (b*: 28.838), while the violet fabrics displayed a significant decrease in K/S and an increase in b*. The combination of ZnO and polyphenol treatment improved UV absorption at 350 to 250 nm. Among the Cu-mordanted fabrics after ZnO/phenols treatment, the violet cotton turned reddish from blueish (negative to positive b*), with a hue change of 316° to 59° and the highest ΔE (25.90 ± 4.34) after UV exposure. In this study, the combination of ZnO/polyphenol with Cu-mordants allowed the Cape jasmine-dyed polyester to achieve a minimum ΔE as well as to keep its chroma and hue after UV exposure.

Low luminance contrast’s effect on the color appearance of S-cone patterns

There is a surprisingly strong effect on color appearance when low levels of luminance contrast are added to visual targets in which only S-cones are modulated. This phenomenon can be studied with checkerboard patterns composed of alternating S-cone-modulated checks and gray checks. + S checks look purple when surrounded by slightly brighter gray checks but look highly desaturated (lavender, almost white) when surrounded by darker gray checks. −S checks change in hue with luminance contrast; they look yellow when surrounded by darker gray checks but are greener when surrounded by lighter checks. Psychophysical paired comparisons confirm these perceptions. Furthermore, visual evoked potentials (VEPs) recorded from human posterior cortex indicate that signals evoked by low luminance contrast interact nonlinearly with S-cone-evoked signals in early cortical color processing. Our new psychophysics and electrophysiology results prove that human perception of color appearance is not based on neural computations within a separate, isolated color system. Rather, signals evoked by color contrast and luminance contrast interact to produce the colors we see.

Transparent coating on a color surface

When a laminate or transparent coating is applied to the surface of a colored slab, there may be a significant change in the color. A reason for the change in color is internal reflection at the slab surface and thus greater selective absorption. The current work develops a random walk model to calculate the reflectance factor of a slab that includes internal reflection at the slab surface to predict the change in color of the bulk reflectance with application of a laminate. The CIELAB colors are calculated from the reflectance, and the model shows that there is not much change in hue but there is significant change in the saturation and lightness: the saturation increases and the lightness decreases. A comparison of the reflectance factor as predicted by the model is compared to a Monte Carlo simulation and shown to have good agreement.

Portable smartphone-assisted ratiometric fluorescent probe for carbimazole visualization detection

The ratio-based probe improves detection precision and accuracy by minimizing the effects of various experimental conditions. Herein, we constructed a ratio fluorescent probe (Si NPs/TGA-functionalized CdTe) using silicon nanoparticles (Si NPs) as the background signal and mercaptoacetic acid-functionalized cadmium telluride quantum dots (TGA-functionalized CdTe) as the responding unit. The interaction between Carbimazole (CBZ) and sulfhydryl groups on the surface of TGA-functionalized CdTe led to a decrease in the fluorescence intensity of the probe, and the color of the solution turned red and pink turned blue. Meanwhile, a test paper-based detection method integrated with the smartphone sensing platform was established to analyze the red, green, and blue (RGB) values in the images of Si NPs/TGA-functionalized CdTe solution before and after the addition of CBZ based on the change of hue, and an analytical model was constructed based on the R/B value and CBZ concentration, realizing rapid visual detection and analysis of CBZ. In addition, the constructed smartphone sensing platform was applied to the detection of CBZ in human urine, and the limit of detection the fluorescence analysis method and the smartphone sensing platform were 40 nM and 63 nM, with the recoveries of 96.5 %-102.7 % and 90.6 %-107.2 %, and the relative standard deviations of 2.7 %-4.1 % and 3.5 %-6.8 %, respectively. This work provides a significant improvement in the proportional sensing of CBZ in human urine and broadens the use of portable quantitative sensing devices in chemical sensing applications.

Natural dyeing of plasma treated wool with avocado seed extract and use of tartaric acid as bio‐mordant

AbstractIn this study, surface modification of wool fabrics by oxygen plasma was carried out to enhance colour, dyeability and fastness properties. Avocado (Persea americana) seed was selected as the natural dye source, plasma activated wool samples were dyed with the extracted colourant and tartaric acid (10% and 20% owf) was used for simultaneous mordanting. All samples exhibited very good washing and dry rubbing fastness grades. It was observed that plasma treated samples have darker and more saturated colours with a persistent hue and increased wet rubbing fastness grades. Applying plasma treatment and using tartaric acid as bio‐mordant provided a noticeable increase in chroma and colour strength, and a slight improvement in fastness to light. Effect of pH of the dye bath on dyeability and the bio‐mordant role of tartaric acid were also investigated for four mordant concentrations (2%, 5%, 10% and 20% owf), and it was detected that using 5% owf or higher concentrations of tartaric acid provided different colour characteristics and dyeability when compared to the dye solutions prepared with inorganic acid. Based on findings of the study, it was concluded that modifying the fabric surface by oxygen plasma can be used to enhance the dyeing performance without causing a major change in the characteristic hue of the colourant extracted from avocado seeds. The use of tartaric acid ‐ solitary or accompanied with plasma treatment ‐ to increase the affinity between the colouring matter and the fibre was also recommended.

UV and blue excited tunable emission of thermally stable Bi3+ sensitized Eu3+ doped calcium aluminozincate phosphor for photonic applications

Bi3+/Eu3+ co-driven calcium aluminozincate (CAZ) phosphor prepared by sol–gel route. Structural analysis was conducted based on X-ray diffractogram. Scanning Electron Microscope images were recorded using Carl Zeiss microscope. Luminescent traits of the said phosphors were identified using excitation and emission spectroscopy at room temperature and elevated temperature. The emission spectra recorded at room temperature under different excitations exhibit variation in spectral behavior. The Commision Internationale de-lElcairage coordinates shown in chromaticity diagram indicate the change in emission hue as pure blue, bluish red and finally pure red by varying the excitation wavelengths. The temperature dependent emission spectra show decrease in emission intensity with temperature and activation energy found to be 0.280 eV. The decay curves were also recorded to determine lifetime and study energy transfer between Bi3+ and Eu3+ ions. Auzel’s fit conducted based on the decay lifetimes helps in evaluating quantum efficiency theoretically. All these investigations authorize the potential of Bi3+/Eu3+ doped CAZ phosphors for their utilization as color-tunable phosphor in photonic applications.

Flexible Inorganic All-Solid-State Electrochromic Devices toward Visual Energy Storage and Two-Dimensional Color Tunability

Multicolor display has gradually become a sought-after trend for electrochromic devices due to its broadened application scope. Meanwhile, the advantages of inorganic electrochromic devices such as stable electrochemical performance and good energy storage ability also have great attraction in practical production applications. However, there are still huge challenges for inorganic electrochromic materials to achieve multicolor transformation due to their single-color hue change. Herein, we design an inorganic and multicolor electrochromic energy storage device (MEESD) exhibiting flexibility and all-solid-state merits. Prussian blue (PB) and MnO2, as the asymmetrical electrodes of this MEESD, show good pseudocapacitance property, matching charge capacity, and obvious color change. As a typical electrochromic device, the MEESD shows a fast response of 0.5 s and good coloration efficiency of 144.2 cm2/C. As an energy storage device, the MEESD presents excellent rate capability and volumetric energy/power density (84.2 mWh cm-3/23.3 W cm-3). Its energy level can be visually monitored by color contrast and optical modulation. In the charging/discharging process, its color can obviously change to various degrees of yellow, green, and blue along with 40% wide optical modulation at 710 nm. Meanwhile, the stability of the MEESD in a common and humidity environment was analyzed in detail from electrochemical, optical, and energy storage aspects. This work provides feasible thoughts to design multifunctional electrochromic devices integrated with inorganic, flexible, all-solid-state, multicolor, and energy storage properties.

Scorpionfish rapidly change colour in response to their background

BackgroundTo facilitate background matching in heterogenous environments, some animals rapidly change body colouration. Marine predatory fishes might use this ability to hide from predators and prey. Here, we focus on scorpionfishes (Scorpaenidae), well-camouflaged, bottom-dwelling sit-and-wait predators. We tested whether Scorpaena maderensis and Scorpaena porcus adjust body luminance and hue in response to three artificial backgrounds and thereby achieve background matching. Both scorpionfish species are also red fluorescent, which could contribute to background matching at depth. Therefore, we tested whether red fluorescence is also regulated in response to different backgrounds. The darkest and the lightest backgrounds were grey, while the third background was orange of intermediate luminance. Scorpionfish were placed on all three backgrounds in a randomised repeated measures design. We documented changes in scorpionfish luminance and hue with image analysis and calculated contrast to the backgrounds. Changes were quantified from the visual perspective of two potential prey fishes, the triplefin Tripterygion delaisi and the goby Pomatoschistus flavescens. Additionally, we measured changes in the area of scorpionfish red fluorescence. Because scorpionfish changed quicker than initially expected, we measured luminance change at a higher temporal resolution in a second experiment.ResultsBoth scorpionfish species rapidly adjusted luminance and hue in response to a change of background. From prey visual perspective, scorpionfishes’ body achromatic and chromatic contrasts against the background were high, indicating imperfect background matching. Chromatic contrasts differed considerably between the two observer species, highlighting the importance of choosing natural observers with care when studying camouflage. Scorpionfish displayed larger areas of red fluorescence with increasing luminance of the background. With the second experiment, we showed that about 50% of the total luminance change observed after one minute is achieved very rapidly, in five to ten seconds.ConclusionBoth scorpionfish species change body luminance and hue in response to different backgrounds within seconds. While the achieved background matching was suboptimal for the artificial backgrounds, we propose that the observed changes were intended to reduce detectability, and are an essential strategy to camouflage in the natural environment.

The kinetics of strawberry quality changes during the shelf-life

Strawberries have a relatively short postharvest life due to their quick softening and decay. When the supply chain is too far along to make logistical adjustments to meet shelf life, quality loss and shelf-life reduction often accelerates with rising temperature. The purpose of this study is to use kinetic modelling to explain how characteristics of strawberry quality vary while they are being stored. To measure the qualities of redness (a*), lightness (L*), chroma colour (C*), weight loss (WL), total soluble solids (TSS), titratable acidity (TA), and total phenolic content (TPC), fresh strawberries were obtained from a farm and stored for 8 days at 4°C and 10°C. The experimental results showed that strawberry quality characteristics stored at 10 °C had a strong and significant impact. After being stored at 10°C, the properties of redness (a*) and lightness (L*) quickly converted to darker zone. During storage at 10 °C, a significant rise in weight loss and chroma was seen with a less apparent decrease in L*. Zero-order and first-order models are used to characterize quality changes that occur during storage. The WL, TSS, and TA properties were best described by the zero-order model. On the contrary, the hue change was described by the first-order model. The results demonstrate that kinetic models fall short in their ability to characterize changes in TPC property during storage. In comparison to strawberries stored at 10°C, the strawberries stored at 4°C carried out the desired result of weight loss, colour change, and TA change.

Textile-Based Volatile Organic Compound Sensors Using Cellulose Fabrics and Direct Dyes

ABSTRACT In order to fabricate colorimetric textile sensors detecting gas phase of volatile organic compounds (VOCs), 11 kinds of direct dyes were investigated for 13 types of VOCs. Direct Violet 51 was chosen for its best sensing performance both instrumentally and visibly. Direct Violet 51 exhibited the change of color strength and color hue by exposure VOCs. The dyed cotton fabrics detected polar VOCs well, especially N,N-dimethylformamide (DMF). The colorimetric cotton-based textile sensor dyed with Direct Violet 51 exhibited approximately 10 of color difference (ΔE) under 10 ppm DMF gas within 100 min, and the maximum absorption wavelength was shifted from 560 nm to 530 nm. The sensing mechanisms could be summarized in three factors: solvatochromism and aggregative characteristics from the point of view of dye, and adsorption amount of VOCs for fabric. The colorimetric textile sensor retained its sensing performance after 10 cycle tests.

Thermal and pH stability of Justicia spicigera (Mexican honeysuckle) pigments: Application of mathematical probabilistic models to predict pigments stability

Kinetic and probabilistic (Time-to-Failure, TTF) models were used to predict the color (L*, a*, b* total color differences (ΔE), Hue and Chroma) stability of Justicia spicigera leaves pigments subjected to different temperatures (40 – 80 °C) and pHs (2 – 12). The change in pH caused different hues (from 60° = orange red to 268° = deep-blue) due to the shift effect of anthocyanins in the extract. Temperatures higher than 60 °C increased the color degradation. High heat sensitivity was observed at pH 4 (Ea = 90.27) and 10 (Ea = 154.99 kJ/mol). The Time-to-Failure model for both ΔE and Hue describes the effect of pH and temperature in the J. spicigera extracts. High pHs and temperatures applied to the extracts increased the probability of showing ΔEs > 4 or Hue changes over 20 %. Nearby the neutral region of pH, pigments of J. spicigera were more stable. The TTF model might be a useful tool to describe and predict the behavior of pigments added to foods.

Contactless skin perfusion monitoring with video cameras: tracking pharmacological vasoconstriction and vasodilation using photoplethysmographic changes

Objectives. Clinical assessment of skin perfusion informs prognosis in critically ill patients. Video camera monitoring could provide an objective, continuous method to monitor skin perfusion. In this prospective, interventional study of healthy volunteers, we tested whether video camera-derived photoplethysmography imaging and colour measurements could detect drug-induced skin perfusion changes. Approach. We monitored the lower limbs of 30 volunteers using video cameras while administering phenylephrine (a vasoconstrictor) and glyceryl trinitrate (a vasodilator). We report relative pixel intensity changes from baseline, as absolute values are sensitive to environmental factors. The primary outcome was the pre- to peak- infusion green channel amplitude change in the pulsatile PPGi waveform component. Secondary outcomes were pre-to-peak changes in the photoplethysmographic imaging waveform baseline, skin colour hue and skin colour saturation. Main results. The 30 participants had a median age of 29 years (IQR 25–34), sixteen (53%) were male. A 34.7% (p = 0.0001) mean decrease in the amplitude of the pulsatile photoplethysmographic imaging waveform occurred following phenylephrine infusion. A 30.7% (p = 0.000004) mean increase occurred following glyceryl trinitrate infusion. The photoplethysmographic imaging baseline decreased with phenylephrine by 2.1% (p = 0.000 02) and increased with glyceryl trinitrate by 0.5% (p = 0.026). Skin colour hue changed in opposite direction with phenylephrine (−0.0013, p = 0.0002) and glyceryl trinitrate (+0.0006, p = 0.019). Skin colour saturation decreased with phenylephrine by 0.0022 (p = 0.0002), with no significant change observed with glyceryl trinitrate (+0.0005, p = 0.21). Significance. Drug-induced vasoconstriction and vasodilation are associated with detectable changes in photoplethysmographic imaging waveform parameters and skin hue. Our findings suggest video cameras have great potential for continuous, contactless skin perfusion monitoring.

Wood discoloration patterns depending on the light source

The wood photodegradation, including discolouration caused by exposure to UV and solar radiation, has been intensively studied, while the effect of artificial lighting on wood has been little investigated. In the present study, the effect of three types of artificial light sources (LED, incandescent, and fluorescent lamps) on the colour changes of wood was evaluated. LEDs with high (6500 K) and low (3000 K) correlated colour temperature were employed in the experiments. Wood colour was assessed by spectrophotometric measurements of reflectance spectra, which were converted into colour parameters of the CIELAB colour system. The total discolouration as well as the changes in colour lightness, chroma (saturation), and hue were evaluated for two hardwood species (birch, oak) and two softwood species (spruce, pine - sapwood and heartwood) depending on the irradiation dose. Visually perceivable changes in colour of all woods were observed already at relatively low irradiation doses, indicating a high sensitivity of the wood to radiation emitted by artificial light sources. Comparing the softwoods and hardwoods included in the study, the latter proved to be more resistant to discolouration caused by the tested light sources. Overall, greater colour changes in long-term exposure were caused by incandescent and fluorescent lamps, although more rapid discolouration developed in the early stage irradiation with LEDs. A substantial difference between the effect of the tested LEDs was only observed in the initial phase, when the cool LED (6500 K) caused more discolouration. The changes in the colour parameters were complex and varying in directions, including a reversal with the accumulation of the irradiation dose, indicating that the exposure to artificial light sources resulted in continuous alteration in the shade of the wood colour.

Eco-Friendly Dyeing of Cotton and Wool Fabrics with Avocado Seed and Peel Extracts

ABSTRACT In this study, agricultural waste of avocado (Persea americana) was proposed as a natural dye source for eco-friendly and sustainable dyeing of textiles. Woven fabrics made of cotton and wool were pre-mordanted with nontoxic metallic salts; alum and ferrous sulfate and dyed with the pigments extracted from avocado seeds and peels. All samples exhibited very good washing and rubbing fastness grades. Pre-mordanting fabrics with ferrous sulfate provided a different color, a noticeable increase in dyeability and a significant improvement in fastness to light. On the other hand, in case of using alum, only a slight change in chroma and hue was recorded. Based on findings of the study, it was concluded that the extracted pigments have strong affinity for protein fibers and a relatively lower affinity for cellulosic fibers. It was also observed that the samples dyed with peel extract have darker and more saturated colors, a more persistent hue and higher light fastness grades when compared to the corresponding samples dyed with seed extract.

DEVELOPMENT OF CLEANING EVALUATION APPLICATION USING HUE CHANGE AS A PARAMETER

In the field of cleaning, there is a method to evaluate the amount of soiling by processing the color signal of an image of a soiled sample using the Kubelka-Munka formula, but this method could not be adapted to the case where the hue changes due to cleaning or washing. In this study, we aimed to construct a system to quantify the amount of soiling corresponding to the hue change.We conducted a cleaning experiment using a sample of iron oxide, which changes from yellowish-brown to black by reduction, as a model soiling on fabric and evaluated the accuracy of the image analysis method by comparing it with the results of XRF analysis of the sample after cleaning.As a result, it was found that the change in the hue of iron oxides due to reduction could be clearly captured as a color signal, and the degree of reduction of iron oxides could be determined from the xy value. Using the results, we were able to construct an algorithm that can accurately determine the amount of dirt adhesion by recalculating the hue change as a variable.This achievement has greatly expanded the range of objects for which the amount of soiling from the exterior can be evaluated.

CIEDE2000 lightness, chroma and hue human gingiva thresholds

Objective: To determine the visual 50:50% perceptibility and acceptability CIEDE2000 lightness, chroma and hue human gingiva thresholds. Methods: A psychophysical experiment based on visual assessments of simulated images of human gingiva on a calibrated display was performed. A 20-obsever panel (dentists and laypersons; n=10) evaluated three subsets of simulated human gingiva: lightness subset (|ΔL′/ΔE00|≥ 0.98); chroma subset (|ΔC′/ΔE00|≥ 0.98) and hue subset (|ΔH′/ΔE00|≥ 0.96) using ΔE00< 5 units. A Takagi-Sugeno-Kang (TSK) Fuzzy Approximation model was used as fitting procedure, and 50:50% perceptibility threshold (PT) and acceptability threshold (AT) were calculated. Data was statistically analyzed using t-test (p ≤ 0.05). Results: The 50:50% PT were ΔL’ = 0.74 (95% confidence interval (CI) 0.39−1.09); ΔC’ = 1.10 (95% CI 0.57−1.46); ΔH’ = 2.40 (95% CI 1.66->3.85). The 50:50% AT were ΔL’ = 2.57 (95% CI 2.00−3.06); ΔC’ = 2.70 (95% CI 2.19−3.38). AT ΔH’ may be considered no computable. PT values were statistically significant among the three metric differences (p ≤ 0.05). No difference was found between observers for PT values. Conclusions: Statistically differences in perceptual limit were found among hue, lightness and chroma for human gingiva. Thus, the observers seem to show lower sensitivity for changes in hue (ΔH′) than in chroma (ΔC′) and in lightness (ΔL′) in the gingiva color space. Clinical significance: PT and AT for lightness, chroma and hue specific for human gingiva should be used when evaluating natural gingiva, pink gingival shade guides or pink materials, since the thresholds of perception and acceptability for teeth are not suitable.

Properties of Oaxaca Cheese Elaborated with Ultrasound-Treated Raw Milk: Physicochemical and Microbiological Parameters.

The effect of ultrasound-treated fresh raw milk upon yield, physicochemical and microbiological quality of Oaxaca cheese was evaluated under a factorial design. The ultrasound frequencies tested were 25 and 45 kHz, during 15 or 30 min. The cheeses made with the ultrasonicated milk (30 min, high-intensity ultrasound, HIU) had greater luminosity without significant changes in hue or chroma, as compared to the controls with no HIU. The yield improved significantly (by up to 2.8 kg/100 L of milk), as the ultrasound treatment time increased. Such cheese yield is attributable to the higher protein content, which was up to 1.5% higher, after sonication. Long-treatment time (30 min) at 25 kHz significantly lowered mesophilic bacteria counts down to limits allowed by current regulations and favors the growth of lactic acid bacteria (LAB) while lowering mold and yeast counts. The absence of E. coli and Salmonella spp. and the decrease in S. aureus counts in Oaxaca cheese were attributed to the mixing of the paste with hot water, inherent to the traditional elaboration process, and to the antagonistic effect of the ultrasound-triggered increased LAB on pathogenic bacteria. Since the artisanal elaboration of Oaxaca cheese does not comply with the current Mexican regulations regarding mesophiles, ultrasound could be a suitable technology to protect its genuine elaboration process with raw milk.

Beetle iridescence induces an avoidance response in naïve avian predators

It has recently been found that iridescence, a taxonomically widespread form of animal coloration defined by a change in hue with viewing angle, can act as a highly effective form of camouflage. However, little is known about whether iridescence can confer a survival benefit to prey postdetection and, if so, which optical properties of iridescent prey are important for this putative protective function. Here, we tested the effects of both iridescence and surface gloss (i.e. specular reflection) on the attack behaviour of prey-naïve avian predators. Using real and artificial jewel beetle, Sternocera aequisignata , wing cases, we found that iridescence provides initial protection against avian predation by significantly reducing the willingness to attack. Importantly, we found that the main factor explaining this aversion is iridescence, not multiple colours per se, with surface gloss also having an independent effect. Our results are important because they demonstrate that even when prey are presented up close and against a mismatching background, iridescence may confer a survival benefit by inducing hesitation or even, as sometimes observed, an aversion response in attacking birds. Furthermore, this means that even postdetection, prey do not necessarily need to have secondary defences such as sharp spines or toxins for iridescence to have a protective effect. Taken together, our results suggest that reduced avian predation could facilitate the initial evolution of iridescence in many species of insects and that it is the defining feature of iridescence, its colour changeability, that is important for this effect. • Iridescence and gloss are usually associated with display, but can they also defend? • We tested naïve birds' willingness to attack glossy and iridescent prey. • Iridescence reduced attack probability, with gloss also having an independent effect. • Iridescence and gloss could provide a survival benefit to prey, even postdetection.

Reversible Mechanochromisms via Manipulating Surface Wrinkling.

Mechanochromic structural-colored materials have promising applications in various domains. In this Letter, we report three types of reversible mechanochromisms in simple material systems by harnessing mechano-responsive wrinkling dynamics including (i) brightness mechanochromism (BM), (ii) hue change mechanochromism (HCM), and (iii) viewable angle mechanochromism (VAM). Upon stretching, the BM device exhibits almost a constant hue but reduces light brightness due to the postbuckling mechanics-controlled deformation, while the HCM device can change the hue from blue to red with almost constant intensity because of the linear elastic mechanics-controlled deformation. The VAM device shows a constant hue because of the thin film interference effect. However, the viewable angles decrease with increasing applied strain owing to the light scattering of wrinkles. All of the mechanochromic behaviors exhibit good reversibility and durability. We clearly elucidated the underlying mechanisms for different mechanochromisms and demonstrated their potential applications in smart displays, stretchable strain sensors, and antipeeping/anticounterfeiting devices.

Digital humanities and technical communication pedagogy

Technical communication instructors, especially those with expertise in visual rhetoric, information design, or multimedia writing are well-suited to teach an introductory Digital Humanities (DH) course. Offering a DH course provides an opportunity to reach extrafield audiences and work with students from a variety of humanities disciplines who may not have the option of taking such a course in their home department. The article advocates for a DH course that offers a methods-driven pedagogy that engages students with active learning by requiring them to research, dissect, and report on existing DH projects, as well as work with existing datasets and methods from prior student research projects or existing DH tools. The sample student project reviewed here uses the data visualization software ImagePlot, and discussion includes how the student used the tool to examine changes in brightness, hue, and color saturation, as well as calculate the total number of distinct shapes from 397 comic book covers. Ultimately, the students are tasked with developing a research question and moving to an articulated methods-driven approach for exploring the question. The student project along with the tools and sample datasets available with them are treated as a module that may be included in an introductory DH course syllabus or training session.