영화에서의 초점이동의 미학

배상준 한국영상학회 2014 한국영상학회 논문집 Vol.12 No.3

본 연구는 영화에서 구사되는 초점이동(rack focus) 기법의 기능과 영화미학적 효과에 관해 분석하였다. 초점이동은 핵심기능은 관객의 주의/관심 끌기이지만, 보다 광범위한 차원에서 영화미학적 효과를 이끌어내는 장치로 파악할 수 있다. 즉 초점이동은 영화의 다양한 표현수단들 중의 하나로서, 시공간의 연속성을 유지하고 창의적 재생산을 가능하게 한다. 또한 초점이동에 의한 이미지의 변화는 등장인물의 내면세계를 환기시키고 감정의 변화를 시각화한다. 초점이동을 낮은 초점심도에서 구사되는 초점과 탈초점의 상호유기적인 관계라 규정할 때, 초점이동은 몽타주와 마찬가지로 각각의 콘텍스트에 따라 상이한 서사맥락을 창조하는 기능을 수행까지 한다. 그리고 초점이동의 이러한 속성은 결국 영화가 3차원적 현실의 2차원적 재현이라는 사실을 공공연히 드러내는, 즉 영화의 자기반영적 특징을 제시하는 장치라는 사실로 귀결될 수 있다. 이렇게 커뮤니케이션을 위한 정보들의 조직과 구성에 기여하는 초점이동은 (카메라)감독의 창의적 손길로 보아야 할 것이다. The purpose of this study is an analysis of the functions and aesthetic effects of rack focus in feature film. The common significant function of rack focus is the attention-steering, but it should be identified as an apparatus too which produces film aesthetic effects. The rack focus, as one of various media for the filmic expressions, sustains the continuity of time and space and is also able to recreate that. In addition, the change of image by rack focus arouses the inner world of characters and visualizes the emotional change. When the rack focus is seen as an inter-organic relation between focus and out-focusing on the low depth of focus, it is then able to create divers narrative contexts just like the montage. This attributes of the rack focus finally reveal openly that film is a fundamentally two dimensional reproduction of the three dimensional reality. And that could be interpreted as the filmic self-reflexivity which is contained by the rack focus. Therefore, the rack focus is a result of the creative operation of film director.

Theoretical Analysis of the Gullstrand Schematic Eye through Numerical Equations

Myoung-Hee Lee,Young-Chul Kim 대한시과학회 2021 대한시과학회지 Vol.23 No.3

목적 : 수치 해석을 통해 Gullstrand 모형안에서 광학적 특성(초점거리, 구면수차 및 초점심도)를 분석했다. 방법 : 광학상수 값(방수)이 수정된 Gullstrand 모형안(각막 전·후면, 수정체 피질 전·후면 및 수정체 핵질 전·후면)을 사용하였다. 평행광선이 입사되었을 때 근축 근사 없는 Snell의 법칙에 따른 눈의 광학적 특성을 수치적으로 분석하였다. 결과 : 모형안으로 입사된 모든 평행광선은 입사 높이가 증가할수록 초점거리, 구면수차 및 초점심도에서 각각 비선형적으로 감소, 증가 및 감소한 것으로 나타났으며, 일반적으로 알려진 근축 근사가 적용된 Gullstrand 정식 모형안의 결과와 잘 일치되었다. 결론 : 생체적 분석이 제한될 수밖에 없는 눈의 광학적 특성을 근축 근사 없이 수치적으로 분석할 수 있었다. 이를 기반으로 다양한 눈의 광학적 현상을 이해할 수 있을 것으로 판단된다. Purpose : The optical characteristics (focal length, spherical aberration, and depth of focus) were analyzed in the Gullstrand schematic eye model through numerical analysis. Methods : The Modified Gullstrand schematic eye model (anterior and posterior cornea, crystalline lens cortex, and crystalline lens nucleolus, respectively) with corrected optical constant values (aqueous humor) was used. The optical characteristics of the eye according to Snell's law without paraxial approximation were numerically analyzed when parallel rays were incident. Results : All the parallel rays incident into the eye model showed nonlinear decreases, increases and decreases in focal length, spherical aberration, and depth of focus, respectively, as the incident height increased. moreover, It was consistent with the results of the Gullstrand schematic eye model to which the commonly known paraxial approximation was applied. Conclusion : It was possible to numerically analyze the optical characteristics of the eye, which are inevitably limited to bio-metric analysis, without paraxial approximation. Based on this, it is decided that the optical phenomena of various eyes can be understood.

근시성 난시안에 대한 핀홀 효과 연구

문수경,이명희,김기범,김구재,김영철 대한시과학회 2015 대한시과학회지 Vol.17 No.3

목 적: 근시성 난시안에 대하여 핀홀에 의한 시력변화를 연구하였다. 방 법: 안질환이 없고 질환에 의해 시력손상이 없는 20대에서 30대 성인을 대상으로 하였다. 핀홀의 직 경을 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm로 설정하여, 핀홀렌즈 직경에 따른 시력을 비교하였다. 표준 조도 200 lux와 밝은 조도(380~500 lux)에 대하여 조도에 따른 핀홀시력을 검사하였다. 또한 눈의 상태를 나안 상태, 구면 굴절력 가입상태, 등가구면 굴절력 가입 상태, 세 가지로 구분 하여 핀홀시력을 검사하였다. 결 과: 여섯 가지 조건을 비교하였는데, 나안 상태일 때 조도에 상관없이 가장 직경이 작은 0.5 mm에 서 핀홀시력이 상승하였고, 직경이 커짐에 따라 단계적으로 핀홀시력이 감소하였다. 구면 굴절력과 등가 구 면굴절력을 가입하고, 핀홀시력을 비교하였을 때 1.5 mm, 2.0 mm 직경에서 시력상승이 두드러지게 나타났다. 하지만 0.5 mm 직경에서 오히려 시력이 떨어졌다. 단안 보다 양안에서 핀홀시력이 상승하였다. 결 론: 나안 상태에서 초점심도와 피사체심도, 수차 보정에 영향을 받아 직경이 가장 작은 렌즈에서 시 력이 가장 많이 상승하였다. 구면 굴절력과 등가구면 굴절력 가입상태일 때, 망막 위에 후초선과 최소착란원이 놓이게 되면서 나안 상태에 비해 초점심도와 피사체심도의 영향보다는 망막 조도의 영향이 큰 것으로 보인다. 단일 핀홀렌즈에서도 양안가중효과(binocular summation)의 영향이 있는 것으로 판단된다. Purpose: We analyzed pinhole effect on the visual acuity for the myopic astigmatism. Methods: The subjects, in this study, were in their 20s and 30s woman and man without damaged visual acuity(VA) and ocular disease. We analyzed pinhole lens effect on the VA under the two lighting conditions, common luminance(200 lux) and brighter luminance(380~500 lux) for the pinhole diameter of 0.5~2.0 mm, in this study. For the purpose, we performed comparison analysis the pinhole lens effects for the uncorrected eye, spheric power added eye, equivalent spheric power added eye. Result: We examined pinhole effect for the six conditions, in this study. For the uncorrected eye condition, the biggest VA enhancement is occurred for the smallest pinhole diameter of 0.5mm regardless of intensity of illumination. And the VA decreases the pinhole diameter increases. However, for the add SD and SED conditions, the VA enhancement increases as the diameter increases. And the VA enhancement is more effective for the binocular rather than the monocular. Conclusion: For the uncorrected eye condition, the VA has an inverse relationship to the pinhole diameter because of the depth of focus. On the other hand, for the added SD or ESD condition, the circle of least confusion and/or posterior focal line are locate on retina. It leads that the VA is in direct proportion to the pinhole diameter because of the effect of intensity of illumination. And it seems that the VA is affected by the Binocular summation for a single pinhole lens.

영화에서의 초점이동의 미학

배상준 한국방송학회 2014 한국방송학회 학술대회 논문집 Vol.2014 No.11

디지털 입자 홀로그래피의 입자 초점 심도에 관한 연구

양얀 ( Yan Yang ),강보선 ( Bo Seon Kang ) 한국분무공학회 2009 한국액체미립화학회지 Vol.14 No.2

Analysis of Optical Characteristics on the Gullstrand Schematic Eye through 3D Simulation

Bon-Yeop Koo,Young-Chul Kim 대한시과학회 2021 대한시과학회지 Vol.23 No.3

목적 : 3D 시뮬레이션을 통해 구현된 Gullstrand 모형안에서 눈의 광학적 특성을 분석하였다. 방법 : 시뮬레이션 프로그램인 SPEOS를 이용하여 Gullstrand 모형안을 모델링하였다. 결과 : 모델링된 모형안으로 입사된 평행광선은 모두 망막 앞에 결상하는 것으로 나타났으며, 이는 근사 없이 계산한 결과 및 일반적으로 잘 알려진 결과와 일치하였다. 평행광선의 입사 높이에 따른 초점심도를 분석한 결과 입사 높이에 따라 지수 함수 형태로 급격히 감소하였다. 또한 구면수차는 입사광선의 높이에 따라 비선형적으로 증가하였다. 결론 : 본 연구와 같이 생체적으로 접근이 어려운 눈의 광학적 현상은 시뮬레이션에 따른 결과 분석을 통해 이 해도를 좀 더 높일 수 있고, 눈의 다양한 광학적 현상에 적용될 수 있을 것으로 판단된다. Purpose : This study analyzed the optical properties of the Gullstrand schematic eye model through 3D simulation. Methods : The Gullstrand schematic eye was modelled using the SPEOS simulation program. Results : All parallel rays incident into the eye model appear to be imaged in front of the retina, which is consistent with the calculation results and generally well-known results without approximation. As a result of analyzing the depth of focus in accordance with the incident height of the parallel rays, it rapidly decreased in the form of an exponential function according to the incident height. Also, the spherical aberration increased non-linearly with the height of the incident ray. Conclusion : With this study, it is judged that the understanding of the optical phenomena of the eye, which is difficult to access biologically, can be further enhanced by applying the result analysis in accordance with the simulation, and it can be applied to various optical phenomena seen with the eyes.

영상처리 기법을 이용한 입경 측정시 배경 명도가 측정 정밀도에 미치는 영향

고광웅,이상용,Koh, Kwang-Uoong,Lee, Sang-Yong 대한기계학회 2000 大韓機械學會論文集B Vol.24 No.4

In this study, experiments have been performed to examine the effects of background gray-level on the depth-of-field and on the in-focus criteria. The normalized value of contrast(VC) and the gradient indicator(GI) were used as the in-focus criteria for the small and the large size-ranges of particles, respectively. The slightly larger number of pixels were detected with the brighter background. The maximum of the normalized value of contrast(VCmax) is decreased with the brighter background and its deviation from that with the background gray-level of 160 turned out to be about $pm$15% when the background gray-level changes from 100 to 200. However, the maximum gradient indicator(GImax) changes with the background gray-level within only $pm$5%. The depth-of-field for the VC-applicable particle-size range is largely dependent on the background gray-level. On the other hand, the depth-of-field for the GI-applicable particle-size range changes only slightly with the background gray-level. To keep the normalized standard deviation of the particle size within 0.1, the background gray-level should be set 160$pm$20 for both the VC-applicable and GI-applicable ranges which cover the particle size between $10{\mu}m$ and $300{\mu}m$.

입경측정을 위한 영상처리기법에서 입자 초점면 존재 판단 기준의 설정

고광웅,김주연,이상용,Koh, Kwang Uoong,Kim, Joo Youn,Lee, Sang Yong 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.3

In the present image processing technique, the concept of the gradient indicator(GI) has been introduced to find out the depth-of-field in sizing large particles ranging from $30{\mu}m$ to $30{\mu}m$ where using of the concept of the normalized contrast value(VC) is not appropriate. The gradient indicator is defined as the ratio of the local value to the maximum possible value of the gray-level gradient in an image frame. The gradient indicator decreases with the increases of the particle size and the distance from the exact focal plane. A particle is considered to be in focus when the value of the gradient indicator at its image boundary stays above a critical value. This critical gradient indicator($GI_{critical}$) is defined as the maximum gradient indicator($GI_{max}$) subtracted by a constant ${\Delta}GI$ which is to account for the particle-size effect. In the present ca.so, the value of ${\Delta}GI$ was set to 0.28 to keep the standard deviation of the measured particles mostly within 0.1. It was also confirmed that, to find the depth-of-field for small particles(${\leq}30{\mu}m$) with the same measurement accuracy, tho concept of the critical normalized contrast($VC_{critical}$) is applicable with 85% of the maximum normalized contrast value($VC_{max}$). Finally, the depth-of-field was checked for the size range between $10{\mu}m$ and $300{\mu}m$ when the both in-focus criteria ($GI_{critical}$ and $VC_{critical}$) were adopted. The change of the depth-of-field with the particle size shows good linearity in both the VC-applicable and the GI-applicable ranges with a reasonable accuracy.

광학계의 중앙 차폐와 가우시안 인자가 중심 Spot 분포와 Encircled Energy에 미치는 영향

박성종(Seong Jong Park),심상현(Sang Hyun Sim),정창섭(Chang Sub Chung) 한국안광학회 2005 한국안광학회지 Vol.10 No.4

유화 분석을 위한 현미경 이미지의 다중 초점 기법 연구

김형태,이덕연,최동운,강재현,이동욱 한국정밀공학회 2023 한국정밀공학회지 Vol.40 No.7

During digital microscopy of an oil painting surface it is inconvenient to analyze an entire image due to multiple defocused areas. The defocusing is usually caused by the small depth of the lens and the rough surface curve. Thus, thesemicroscopic images in an oil painting have multiple focal points, which indicates multi-focus images. We present a multifocus fusion synthesizing a focused image from scans based on focal direction and selection of focused places. Based on microscopic characteristics, a common scanned area of the images was defined to unify the lens multiplication. A focus index was applied to each pixel to identify well-focused pixels and generate a mapping image in the focal direction. Subsequently, a median filter was applied to the mapping image and a multifocal image was acquired based on actual pixel values obtained from the mapping image. The proposed method was utilized in analyzing oil painting samples carrying rough surface curves. The multifocal image facilitated the analysis of the oil painting surface and resulted in enhanced quality compared with other methods. The proposed method can be used to generate useful images in scientific and industrial microscopy.