Comparison of remote and in-person tutorials of color appearance phenomena

Accurately describing the effect of lighting on color appearance phenomena is critical for color science education. While it is ideal to conduct in-person tutorials to demonstrate the color appearance fundamentals, laboratory tutorials have been limited due to COVID-19. The limitation of in-person gatherings and the increase popularity of remote teaching help evoke alternative methods to demonstrate color appearance phenomena. Here, a remote tutorial method is described, and results are compared to in-person tutorials. While the remote tutorial had weaker result in representing observers' color experience compared to the in-person lab tutorial, remote demonstrations can be used to demonstrate and discuss the limitations of color imaging, and the difference between the human visual system and digital imaging systems.

Evaluation of Two Dental Digital Imaging Systems Based on Quality Scorings, Burn-Out Effects and Cervical Width Determination

SummaryBackground/Aim: The aim of the present study is to evaluate diagnostic accuracy of two generic image receptors with CMOS and PSP sensors for image quality scoring (IQS), burnout incidences (BI) and cervical widths (CW) with regard to four different exposure times.Material and Methods: 43 incisor teeth within 15 paraffin block models were exposed at 4 different exposure times both for the CMOS and PSP groups, and a total number of 120 images were obtained. All images were evaluated by 3 dentomaxillofacial radiologists via 3 different criteria; IQS, BI, CW.Results: Diagnostic quality scorings between groups displayed statistically significant difference for 0,1; 0,125 and 0,16 sec exposure times. PSP group revealed higher IQS. For 0,125 and 0,16 seconds exposure times, PSP group showed higher percentages of BI. Average CW were lower in PSP group. Although no statistically significant difference was found between average CW vs. exposure times in the CMOS group; PSP group revealed significant differences among exposure times. We can state that, the PSP system displayed higher image quality so exposure times can be reduced, alas, the same conclusion is not possible with CMOS system used.Conclusions: Image quality perception is higher in PSP system we used, compared with CMOS system. PSP system display more burnout effects with increasing exposure times, while CMOS system is constant.

Automatic plankton quantification using deep features

The study of marine plankton data is vital to monitor the health of the world’s oceans. In recent decades, automatic plankton recognition systems have proved useful to address the vast amount of data collected by specially engineered in situ digital imaging systems. At the beginning, these systems were developed and put into operation using traditional automatic classification techniques, which were fed with hand-designed local image descriptors (such as Fourier features), obtaining quite successful results. In the past few years, there have been many advances in the computer vision community with the rebirth of neural networks. In this paper, we leverage how descriptors computed using convolutional neural networks trained with out-of-domain data are useful to replace hand-designed descriptors in the task of estimating the prevalence of each plankton class in a water sample. To achieve this goal, we have designed a broad set of experiments that show how effective these deep features are when working in combination with state-of-the-art quantification algorithms.

Imaging Systems for Diagnosis and Following of the Retinopathy of Prematurity

In recent years, there have been a lot of changes in the diagnosis and follow-up imaging systems of Retinopathy of Prematurity (ROP) in the light of technological developments. Advanced imaging systems play a major role in accurately diagnosing and staging ROP disease, making timely treatment decisions, and documenting and sharing data. In addition, due to increasing medicolegal problems, advanced wide-field digital imaging systems and better fundus photographs are needed. In this study, the properties of conventional imaging systems and new wide-angle imaging systems used for diagnosis and follow-up of ROP were evaluated.

Numerical Evaluation of Image Contrast for Thicker and Thinner Objects among Current Intraoral Digital Imaging Systems

The purpose is to evaluate the performance of current intraoral digital detectors in detail using a precise phantom and new method. Two aluminum step wedges in 0.5 mm steps were exposed by two photostimulable phosphor plate (PSP) systems—one with automatic exposure compensation (AEC) and the other without AEC—and a CCD sensor. Images were obtained with 3 doses at 60 kV. The effect of metallic material also was evaluated. The contrast-to-noise ratio (CNR) for thinner steps and the low contrast value (LCV) for thicker steps were obtained. The CCD system was the best under all conditions (P<0.001), although the Gray value was sensitive to the dose, and the Gray value-dose relation varied greatly. The PSP system with AEC was superior to that without AEC for the LCV (P<0.001) but was inferior to it regarding the CNR (P<0.001). CNR and LCV in the PSP system without AEC were not affected by the metallic plate. Intraoral digital imaging systems should be chosen according to their diagnostic purpose. PSP system with AEC may be the best for detecting molar proximal caries, whereas the PSP system without AEC may be better for evaluating small bone regeneration in periodontal disease. The CCD system provided the best performance.