Single Lens Research Articles

Showdown in the camera sector: Strategies for an industry in decline

The emergence of sophisticated mobile camera technology has created major disruptions for the camera industry. Indeed, incremental improvements in smartphone camera technology over the last decade have prompted a steep decline in the sale of Digital Single Lens Reflex (DSLR) cameras. This study reviews the failure of the DSLR camera industry to counter the threats posed by smartphone cameras by embracing an agile approach to business. The paper proposes a conceptual model that appraises the complex environment of the DSLR camera industry and identifies the factors disrupting existing markets. The model will help businesses in this industry to review the threats posed by the challenger industry and enable them to recognise future market opportunities.

End-to-end learned single lens design using fast differentiable ray tracing.

In traditional imaging system design, the optical lens is often optimized toward the artificial optimization target like modulation transfer function and field-of-view (FoV). This usually leads to complex stacks of lenses. In order to reduce the complexity, we propose an end-to-end single lens imaging system design method. First, the imaging and processing model is established, whose input end is the ground truth image, and the output end is the restored image by Res-Unet. Then, with the optimization target of minimizing the difference between the restored image and the ground truth image, the parameters of the lens surface and the parameters of the restoration algorithm are optimized simultaneously by deep learning. In order to realize the end-to-end design, the imaging model is required to be differentiable to the lens parameters, so a fast differentiable ray tracing model is proposed. A single lens imaging system with high-quality large FoV (47°) has been designed by the end-to-end method. This method will have a wide application prospects in the design of light and small optoelectronic imaging systems.

Green Criminology–Law Interdisciplinarity Towards Multispecies Justice: The Case of Wildlife Trafficking in Vietnam

Green criminology provides a significant opportunity for interdisciplinary engagement to address the many environmental problems of the twenty-first century that are too complex to be solved through a single disciplinary lens. Hall (2014) has called for increased collaboration between green criminologists and legal scholars while also acknowledging that this form of interdisciplinarity is more challenging than for more traditional forms of criminology. This paper adopts Hall’s call as a starting point for a critical exploration of two areas that offer ground for collaboration: positioning analyses of environmental harm within wider regulatory frameworks and considering the ways human and non-human victims interact with ‘the mechanisms of justice’ to exercise ‘environmental rights’ (Hall 2014: 105). We examine these areas drawing on the case of wildlife trafficking in Vietnam. We argue that ‘multispecies justice’ presents a useful framework to progress green criminology–law collaborations in the Vietnamese and other contexts.

Accuracy and Repeatability of Internet-ordered Spectacle Lenses.

Both consumers and eye care practitioners need to know how well online optical vendors conform with the accepted standards for quality and safety. We found that almost 1 in 10 prescriptions failed to meet national standards, which is a significant improvement over previous studies. The purpose of this study was to assess the accuracy and repeatability of spectacle lens prescriptions ordered from a sample of online vendors. Spectacle lens prescriptions were ordered by paid participants with no optical training who were masked to the study objectives. The prescription powers ordered (sphere, cylinder, and axis) were statistically sampled from 1000 previously filled prescriptions. A total of 100 orders were placed with each of three online vendors that included a range of high- and low-powered single vision lenses and progressive addition lenses, and duplicate orders to assess repeatability. An independent certified testing laboratory was contracted to assess conformance with voluntary consensus standards (ANSI Z80.1-2015) and Food and Drug Administration drop-ball safety testing. Lenses not meeting these standards were counted as failures. The overall failure rates for the three vendors were 11.2 ± 3.2% (vendor A), 8.0 ± 2.7% (vendor B), and 8.2 ± 2.8% (vendor C). The repeatability for 20 prescriptions ordered five times from each vendor was high, with correlation coefficients greater than 90%. There were no observed lens impact failures. Almost 1 in 10 spectacle lens prescriptions ordered from three online vendors failed to meet national standards for optical quality. Additional studies are needed to assess eyewear ordered online for other important patient-specific variables that can influence visual performance and ultimate acceptability of prescription eyewear, such as lens placement relative to the visual axis, frame fit, and cosmetic acceptability.

A particle-tracking image pyrometer for characterizing ignition of pulverized coal particles

In this study, a particle-tracking image pyrometer (PTIP) system, based on a high-resolution high-speed camera and a digital single lens reflex (SLR) camera, was proposed to investigate the ignition characteristics of pulverized coal particles. The goal of the PTIP system was to obtain reliable simultaneous measurements of the velocity, diameter, and temperature of individual burning particles. A modified particle-tracking velocimetry (PTV) algorithm was developed to collect the image sequences of individual particles, and it could weed out defocused particles and other odd particles by low-frequency filtration. Moreover, a template matching method was adopted to distinguish particles undergoing different combustion states (homogeneous volatile combustion or heterogeneous coal/char combustion). The experimental validation was carried out under an O2/CO2 atmosphere in an optically accessible flat flame-supported entrained flow reactor. Particles of Shenhua (SH) bituminous coal, in the size range of 70–133 μm, were combusted in the flue gas with gas temperature of 1400 K and O2 concentration of 20%. The diameter-temperature patterns of particles along their trajectories were discussed. Several criteria based on statistical analysis were adopted to divide the combustion process and obtain the ignition delay time (IDT) and devolatilization duration time (DDT).

Smartphone-based Anterior Segment Imaging: A Comparative Diagnostic Accuracy Study of a Potential Tool for Blindness Prevalence Surveys

ABSTRACT Purpose To determine if smartphone photography could be a useful adjunct to blindness prevalence surveys by providing an accurate diagnosis of corneal opacity. Methods A total of 174 patients with infectious keratitis who had undergone corneal culturing over the past 5 years were enrolled in a diagnostic accuracy study at an eye hospital in South India. Both eyes had an ophthalmologist-performed slit lamp examination, followed by anterior segment photography with a handheld digital single lens reflex (SLR) camera and a smartphone camera coupled to an external attachment that provided magnification and illumination. The diagnostic accuracy of photography was assessed relative to slit lamp examination. Results In total, 90 of 174 enrolled participants had a corneal opacity in the cultured eye and no opacity in the contralateral eye, and did not have a penetrating keratoplasty or missing photographs. Relative to slit lamp examination, the sensitivity of corneal opacity diagnosis was 68% (95%CI 58–77%) using the smartphone’s default settings and 59% (95%CI 49–69%) using the SLR, and the specificity was 97% (95%CI 93–100%) for the smartphone and 97% (95%CI 92–100%) for the SLR. The sensitivity of smartphone-based corneal opacity diagnosis was higher for larger scars (81% for opacities 2 mm in diameter or larger), more visually significant scars (100% for eyes with visual acuity worse than 20/400), and more recent scars (85% for eyes cultured in the past 12 months). Conclusion The diagnostic performance of a smartphone coupled to an external attachment, while somewhat variable, demonstrated high specificity and high sensitivity for all but the smallest opacities.

Myopia control with soft multifocal contact lenses: 18-month follow-up.

PURPOSE:The study aimed to establish the outcome of multifocal contact lenses (MFCL) (Multistage + 1.50D and Proclear + 3.00D) on myopia progression and axial length elongation over an 18-month period.METHODS:Thirty myopic schoolchildren (5 males and 25 females) aged between 13 and 15 years were randomly assigned to wear either single vision contact lens (SVCL), Multistage MFCL + 1.50D, or Proclear +3.00D MFCL for 1½ years using a double-masked design. Cycloplegic refraction, corneal curvature, and axial length were measured.RESULTS:Myopia progression was controlled by 38.6% and 66.6% in children wearing Multistage + 1.50D and Proclear +3.00D MFCL, respectively, in comparison to children wearing SVCL over an 18-month period. In terms of axial elongation, this study found a 31.1% and 63.2% control in axial elongation over 18 months of treatment in comparison to the SVCL group. No statistical significant difference in corneal curvature was found between initial and last visits for all the three groups (SVCL, P = 0.90; Multistage + 1.50 MFCL, P = 0.78, and Proclear + 3.00 MFCL, P = 0.05).CONCLUSION:Proclear +3.00D MFCL was revealed to cause slow development of myopia and axial elongation among myopic schoolchildren. MFCL with higher add powers could be more effective on myopia progression in comparison with moderate add powers.

Wide angle holographic video projection display.

Holographic projection displays provide high diffraction efficiency. However, they have a limited projection angle. This work proposes a holographic projection display with a wide angle, which gives an image of size 306mm×161mm at 700 mm and reduced speckle noise. The solution uses single Fourier lens imaging with a frequency filter and hologram generation utilizing complex coding and nonparaxial diffraction. The experiment was performed with a 4K phase-only spatial light modulator (SLM) to prove the high efficiency of the developed numerical tools. Optical reconstruction shows high resolution and high image quality achieved from a single frame. Hence, displaying video at a full frame rate of the SLM is possible.

Alterations in peripheral refraction with spectacles, soft contact lenses and orthokeratology during near viewing: implications for myopia control

ABSTRACT Clinical relevance The peripheral refraction profile in myopes with different corrective modalities varies significantly for both distance and near viewing and will have implications in managing myopia. Background This study investigated how the magnitude of peripheral myopic defocus induced by Ortho-K varies with and without accommodation, and how this compares to single vision spectacles and soft-contact-lenses (SCL). Methods Relative peripheral refraction (RPR) of 18 young adults (spherical equivalent −1.00 D to −4.50 D) was determined along the horizontal meridian (±10°, ±20°, ±25°) during distance (3-metres) and near viewing (0.2-metres), and along vertical meridian (±10°, ±15°) for distance viewing alone. Measurements were obtained in an uncorrected state and with single vision spectacles, soft contact lens and Ortho-K. Changes in RPR and astigmatic components were compared between distance and near viewing with all different modalities. Results A significant interaction (p = 0.02) between relative peripheral refraction and the target distance (distance and near viewing) was found among different refractive modalities. Single overnight Ortho-K lens wear alone led to relative peripheral myopia for both distance (mean RPR ± SE: −0.92 ± 0.21D and −1.04 ± 0.22D) and near viewing (−0.71 ± 0.17D and −0.76 ± 0.20D). Comparisons of relative peripheral refraction between different corrective modalities at each eccentricity indicated statistical significance of RPR at extreme locations along both temporal and nasal meridian (±20 and ±25°, p < 0.05). RPR with soft contact lenses and spectacles were similar for both distance and near viewing (p > 0.05). Conclusion Single overnight Ortho-K lens wear alone shifted the RPR in the myopic direction for both distance and near viewing in comparison with single vision spectacles and soft contact lenses. The Ortho-K lens designs that offer a large amount of mid-peripheral corneal steeping, in-turn leading to high relative peripheral myopia for both distance and near viewing and might offer beneficial effects on myopia control.

The impact of spectacle lenses for myopia control on visual functions.

PurposeSpectacle lenses containing multiple small peripheral elements have been developed for myopia control in children. It is important that their effect on vision be quantified by (i) fixation through the peripheral portion, thereby using foveal vision and (ii) by fixation through the central portion and presentation of peripheral targets.MethodsThe above approaches were used in five studies to evaluate two novel spectacle lens designs: spectacle lenses with Highly Aspherical Lenslets (HAL) and Slightly Aspherical Lenslets (SAL). A single vision lens served as a control. Visually normal adults participated in each study. The first two studies had subjects fixate through the periphery of the lenses. High and low (10%) contrast visual acuity was measured with the Freiburg Vision Test and reading speed for high and low contrast words measured with a sentence generator. The other three studies assessed peripheral vision while subjects fixated through the central portion of the lens. Peripheral contrast sensitivity was measured using two cycles per degree drifting Gabor stimuli. Peripheral motion perception was further evaluated using random dot stimuli. Finally, attention was measured using an established test of useful field of view with three levels of complexity.ResultsThe periphery of the HAL lens significantly reduced low contrast visual acuity, but not high contrast visual acuity, while the effect of the SAL lens was not significant for either. Neither test lens affected reading speed for high contrast words, but the HAL lens significantly affected performance for low contrast words. Neither test lens affected peripheral motion perception or useful field of view.ConclusionsLow contrast visual acuity and reading was slightly reduced while high contrast visual acuity was unaffected when fixating through the periphery of the novel lens designs. None of the peripheral measures of vision was affected by the novel lens designs.

The efficacy of multifocal soft contact lenses for the alleviation of asthenopic symptoms in myopes with accommodative lag

PurposeTo evaluate the efficacy of multifocal soft contact lenses to reduce asthenopic symptoms in myopes with accommodative lag. MethodsTwenty-four myopic participants, aged 18–35 years, with mean spherical equivalent (MSE) of ≤ -0.75D, were recruited in a randomised, double-blind crossover study. All participants were existing contact lens wearer with near orthophoria or esophoria, presenting with subjective asthenopic symptoms at baseline [Convergence Insufficiency Symptom Survey (CISS) score ≥ 21] and a lag of accommodation ≥ +0.75 D. All participants were initially fitted with single vision contact lenses for a one month period. Participants were then randomly assigned 1:1 to wear low add or high add multifocal soft contact lenses for a further month. After this period, the groups were reversed. Data were collected at baseline and following one month’s wear of each lens. Change in CISS score was evaluated as the primary outcome measure, while secondary outcome measures were changes in accommodative lag and heterophoria status. ResultsBaseline CISS score was (mean ± SD) 25.04 ± 4.58. Post-intervention scores were as follows: single vision: 24.46 ± 4.59, low add: 12.17 ± 6.89, high add: 13.71 ± 7.23. Both low add and high add multifocal soft contact lens wear was associated with an improvement in CISS score compared to baseline CISS and single vision (all p < 0.01). No significant difference was found between the CISS score for the baseline CISS and single vision (p = 1.00). No significant difference was found in lag of accommodation between lens conditions (all p > 0.05), however, there was an exophoric shift in near heterophoria between single vision and both multifocal contact lenses (low add: (mean difference 1.33 Δ, p = 0.02; high add: mean difference 1.23 Δ, p = 0.02) but not between habitual spectacle or any other modality (all p > 0.05). ConclusionsThe use of multifocal soft contact lenses for a one-month period was associated with reduced severity of asthenopic symptoms in pre-presbyopic myopes with accommodative lag. Whilst improvement of symptoms does not appear to be mediated by a significant reduction in accommodative lag, changes in heterophoria may play a role in reducing asthenopic symptoms.

Small-scale shear: Peeling off diffuse subhalos with gravitational waves

Subhalos at subgalactic scales ($M\lesssim 10^7 M_\odot$ or $k\gtrsim 10^3 \,{\rm Mpc}^{-1}$) are pristine test beds of dark matter (DM). However, they are too small, diffuse and dark to be visible, in any existing observations. In this paper, we develop a complete formalism for weak and strong diffractive lensing, which can be used to probe such subhalos with chirping gravitational waves (GWs). Also, we show that Navarro-Frenk-White(NFW) subhalos in this mass range can indeed be detected individually, albeit at a rate of ${\cal O}(10)$ or less per year at BBO and others limited by small merger rates and large required SNR $\gtrsim 1/\gamma(r_0) \sim 10^3$. It becomes possible as NFW scale radii $r_0$ are of the right size comparable to the GW Fresnel length $r_F$, and unlike all existing probes, their lensing is more sensitive to lighter subhalos. Remarkably, our formalism further reveals that the frequency dependence of weak lensing (which is actually the detectable effect) is due to shear $\gamma$ at $r_F$. Not only is it consistent with an approximate scaling invariance, but it also offers a new way to measure the mass profile at a successively smaller scale of chirping $r_F \propto f^{-1/2}$. Meanwhile, strong diffraction that produces a blurred Einstein ring has a universal frequency dependence, allowing only detections. These are further demonstrated through semianalytic discussions of power-law profiles. Our developments for a single lens can be generalized and will promote diffractive lensing to a more concrete and promising physics in probing DM and small-scale structures.

Scleral lens prescription and management practices: Emerging consensus

PurposeTo describe international scleral lens prescription and management practices across multiple practice types. MethodsFor this cross-sectional study, scleral lens practitioners were asked to complete an electronic survey that requested information about a single scleral lens patient. Data collected included practitioner demographics (practice type, country, years of experience) and patient indications for scleral lens wear, fitting process, lens design, and care products. ResultsData were collected for 259 patients (419 eyes). Most participants (60%) practiced in the US, 75% worked primarily in community practice, and 58% claimed more than 5 years’ experience fitting scleral lenses. Indications for scleral lens wear were corneal irregularity (87%), ocular surface disease (9%), and uncomplicated refractive error (4%). During the fitting process, the mean (SD) number of lenses ordered was 2.4 (1.6) (range, 1–16 lenses) during 3.8 (2.4) visits (range, 1–18 visits). Of patients, 62% used a daily surfactant cleaner, 47% used hydrogen peroxide disinfection, and 67% used single-use vials of nonpreserved saline. Mean lens diameter was 16.2 (1.1) mm (range, 11.8–23.0 mm). The landing zones were spherical (64%), toric (26%), quadrant-specific (7%), and custom (3%) designs. Optical power was spherical in 70%, toric in 27%, and higher-order aberration correcting in 3% of lenses. Only 5 lenses had multifocal optics. ConclusionsGeneral consensus regarding prescribing patterns (lens design, wearing schedules, care products) between US vs non-US, community vs academic, and new vs established providers is reported in this study. Relatively low percentages of patients wearing lenses with advanced landing zones or optical designs suggest that these new options have not been widely adopted.

Identifying low-amplitude pulsating stars through microlensing observations

ABSTRACT One possibility for detecting low-amplitude pulsational variations is through gravitational microlensing. During a microlensing event, the temporary brightness increase leads to improvement in the signal-to-noise ratio, and thereby better detectability of pulsational signatures in light curves. We explore this possibility under two primary considerations. The first is when the standard point-source and point-lens approximation applies. In this scenario, dividing the observed light curve by the best-fitted microlensing model leads to residuals that result in pulsational features with improved uncertainties. The second is for transit events (single lens) or caustic crossing (binary lens). The point-source approximation breaks down, and residuals relative to a simple best-fitted microlensing model display more complex behaviour. We employ a Monte Carlo simulation of microlensing of pulsating variables toward the Galactic bulge for the surveys of OGLE and of KMTNet. We demonstrate that the efficiency for detecting pulsational signatures with intrinsic amplitudes of &amp;lt;0.25 mag during single and binary microlensing events, at differences in χ2 of Δχ2 &amp;gt; 350, is $\sim \!50\!-\!60{{\ \rm per\ cent}}$. The maximum efficiency occurs for pulsational periods P ≃ 0.1–0.3 d. We also study the possibility that high-magnification microlensing events of non-radially pulsating stars could be misinterpreted as planetary or binary microlensing events. We conclude that small asymmetric features around light curve peaks due to stellar pulsations could be misdiagnosed with crossing (or passing close to) small caustic curves.

What are patients' beliefs about, and experiences of, adaptation to glasses and how does this affect their wearing habits?

It is well known that some patients experience difficulties adapting to new glasses. However, little is known about what patients themselves understand of the adaptation process, and how this influences their attitudes and the decisions they make when adapting to a new pair of glasses. Nor is it understood whether these factors affect their wearing habits. We conducted four focus groups. Participants were 22glasses wearers (mean±SD age 43±14years, range 21-71years) who reported they: (1) wore spectacle correction for distance vision (single vision, bifocal or progressive lenses); (2) had struggled to get used to a new pair of glasses and (3) sometimes chose not to wear their distance correction. Focus groups were audio recorded, transcribed verbatim and analysed thematically. We identified three themes. Trust is about how participants' trust in their optometrist and themselves influences the likelihood of them adapting successfully to new glasses. Conflict describes how the advice patients have received about adapting to glasses can conflict with what they have experienced and how this conflict influences their expectations. Part of Me explores how participants' experiences and feelings about their glasses are important to adaptation and this includes physical, visual, emotional and behavioural aspects. The traditional optometric perspective of adaptation to glasses is much narrower than that held by patients, and significantly underestimates the physical, behavioural and emotional adaptation that patients must go through in order to feel fully comfortable wearing their glasses. Patients should receive significantly more information about adaptation, including symptoms that may be experienced and why these happen, practical tips to aid adaptation, and when and how to raise concerns. Patients should also receive information about the day-to-day effects of blur adaptation to avoid them not wearing their glasses, including for vision-critical tasks such as driving.

Design and simulation of interferometer for synchrotron radiation beam size measurement

The interferometric measurement of the transverse beam size based on synchrotron radiation is a non-intercepting high precision measurement method. Compared with the imaging method, the interferometric method can measure smaller beam size and get better resolution. It is expected to obtain submicron resolution at shorter measurement wavelength, so it is widely used in synchrotron radiation sources. The upgraded scheme of current interference device in Hefei Light Source HLS-II is presented in this paper. It is proposed to replace the first focusing lens in the original interference light path with an RC structure focusing mirror, and the second single lens with a doublet lens. The design goal of this paper is to reduce dispersion and geometric aberration without changing the optical axis of the optical path, so as to improve the imaging quality of the optical path. The geometrical optical path design is used to evaluate the imaging quality of the optical path, and physical optical simulation is performed to obtain the interference fringes of the measurement system. The simulation results show that the radius of Airy spot is reduced by about 35%, the root mean square radius of dot array is reduced by about 99%, the wavefront difference is reduced by about 75%, and the cutoff frequency of MTF function is increased by about 65%, using a focusing mirror to replace the original focusing lens can greatly improve the image quality of the optical path.

The Development of Long-Distance Viewing Direction Analysis and Recognition of Observed Objects Using Head Image and Deep Learning

In this study, we use OpenPose to capture many facial feature nodes, create a data set and label it, and finally bring in the neural network model we created. The purpose is to predict the direction of the person’s line of sight from the face and facial feature nodes and finally add object detection technology to calculate the object that the person is observing. After implementing this method, we found that this method can correctly estimate the human body’s form. Furthermore, if multiple lenses can get more information, the effect will be better than a single lens, evaluating the observed objects more accurately. Furthermore, we found that the head in the image can judge the direction of view. In addition, we found that in the case of the test face tilt, approximately at a tilt angle of 60 degrees, the face nodes can still be captured. Similarly, when the inclination angle is greater than 60 degrees, the facing node cannot be used.

Dual-wavelength excitation combined Raman spectroscopy for detection of highly fluorescent samples.

As fluorescence is the major limitation in Raman scattering, near-infrared excitation wavelength (>780nm) is preferred for fluorescence suppression in Raman spectroscopy. To reduce the risk of fluorescence interference, we developed a dual-wavelength excitation combined Raman spectroscopy (DWECRS) system at 785 and 830 nm. By a common optical path, each laser beam was focused on the same region of the sample by a single objective lens, and the dual-wavelength excitation Raman spectra were detected by a single CCD detector; in addition, 785 and 830 nm excitation Raman spectra can be directly constructed as combined Raman spectrum in the DWECRS system. The results of pure peanut oil and glycerol indicate that the combined Raman spectrum cannot only reduce fluorescence interference but also keep a high signal-to-noise ratio in the high-wavenumber region. The results of dye-ethanol solutions with different concentrations show that the handheld DWECRS system can be used as a smart method to dodge strong fluorescence. Furthermore, we developed a peak intensity ratio method with the DWECRS system to distinguish different types of edible oils. The peak intensity ratio distribution chart of edible oils showed each oil normalized center was relatively independent and nonoverlapped, which can be used as the basis of edible oil classification analysis. In the future, the DWECRS system has potential to be used as a tool for more complex applications.

English

The matrix optics formalism is applied to show that a simple Gaussian equation is enough to relate object and image distances in an optical system consisting of an arbitrary number of thick lenses in cascade immersed in air. First, the case of a single thick lens was studied. Applying sequentially the optical matrixes corresponding to refraction and displacement of the optical ray, and imposing certain conditions on the behavior of the bunch of rays being refracted by the lens, there were found characteristic parameters such as focal distance, back and front focal points, and principal planes. Then the equation relating object and image distances is found, which, after a coordinate transformation, becomes the well-known Gaussian equation, usually used to describe the more idealized case of thin lens. Further, the formalism is extended to compound systems of two, three and N thick lenses in cascade. It is also found that a simple Gaussian equation is sufficient to relate object and image distances no matter the number of lenses. Key words: Matrix optics, thick lenses, back focal length, front focal length, principal planes, focus, multi-lenses system.

The iPhone, the reflex, and the vinyl record: is the smartphone taking the best intraoperative photographs?

Surgical field photography is a tough exercise: surgeons dedicate the required time for photography even during complex surgeries; the intense lighting of the operating field works against photography, and the surgeon has to utilise whatever equipment is available. We selected five complex interventions and two surgeons (one with an iPhone® and one with a Digital Single Lens Reflex [DSLR] camera) who each took a photograph of the operating field. The source of photographs was blinded, and the image quality was scored using a 5-point Likert scale by three groups of team members with differing experiences: six senior surgeons, two junior surgeons, and four surgical residents. We evaluated the resolution (adequate for clinical interpretation), colour (appear true and natural), contrast (adequate to distinguish different structures), and overall quality. The mean ± SEM overall image quality was similar for both the smartphone and DSLR (3.7 ± 0.1 vs. 3.8 ± 0.11; p = 0.87), as were most of the scores for each image characteristic. Surgeons seek objectivity and efficiency. The smartphone is a more convenient photographic equipment and produces identical results than the DSLR. Human beings can be sensitive to image quality. The DSLR image was found to be sharper, however, this was found to be imperceptible.