SU1688447A1 - Television device for visual color analysis and determination of color setting parameters for photo printing - Google Patents

Abstract

The invention relates to a communication technique and can be used in devices carrying out electronic correction of light in color phototelegraphy and photography. The aim of the invention is to improve the accuracy. A television device for visual color analysis and determination of color setting parameters for photo printing contains a source of light 1, a condenser 2, a first block of 3 zonal light filters, a tape recording mechanism with photographic material 4, a lens 5, an electron beam transmission television tube 6, a video amplifier 7, a gamma corrector 8 , kinescope 9, first optical compensation filter 10, subtractive color head 11, synchronizer 12, second optical compensation filter 13, second block 14 of zone filters, attenuator 15. P improve the accuracy provided by taking into account the actual parameter photographic elements and significantly simplify transceiver tract. 1il (L o o 00 00 VI

Description

l / lanhpeieuMp is a communication technology and can be used in devices that electronically correct light in color phototelegraphy and photography.

The aim of the invention is to improve the accuracy.

The drawing shows a block diagram of a television device for visual color analysis and determination of color setting parameters for photo printing. Telepitionno 1 device for visual color analysis and determination of color-mounting parameters for Photo printing contains source 1 of light, condenser 2, first unit 3 zonal light filters, tape drive mechanism (LPM) 4 with photographic film, lens 5, electron beam transmitting television tube (CRT) b, video amplifier 7, gamma corrector 8, kinescope 9, first compensation optical filter 10, subtractive color head 11, synchronizer 12, second optical compensation filter 13, second block 14 of zonal filters, weakened 15 Tel.

The device works as follows.

The light beam of the light source 1 is transformed by the condenser 2 and, passing through the first block 3 zonal light filters, illuminates the negative set on the LLM 4. The image from the negative is projected with the help of the objective 5 onto the target d) L1 (

For reproduction, a black and white kinescope 9 is used. In front of the screen of which a second compensation optical filter 13 is installed, which is used to match the spectral characteristics of the phosphor with the characteristics of the source 1 of the light.

The spectral composition at the input and output of the device is corrected by the first 3 and second 14 blocks of the zonal filters. The output color image is synthesized by the method of sequential alternation of color separations in the main color (cut blue, green).

The filters in the zonal filter units 3 and 14 alternate synchronously with a frequency of 1/2 frame scanning, i.e. one color separation image is transmitted for one half frame. A synchronous filter change is provided by a synchronizer 12, the frequency of issuing control actions of which is stabilized by a quartz d d generator.

In the path of the light beam, a subtractive color head 11 and a first compensation optical filter 10 are installed in front of the first block of zonal light filters 3, which are used to match the spectral characteristics of source 1

light, which is used in printing, with spectral characteristics of a CRT 6 and partly with characteristics of a negative (film) on LSM 4. The first block of 3 zonal filters has transmission characteristics corresponding to the sensitivity of individual layers of colored positive material used in photo printing.

Spectral characteristics of the second

the block of zone light filters 14 correspond to the transmission spectrum of the dyes of the positive material used (in the combination of colors of the emulsion layers: purple and cyan, cyan and yellow,

yellow and purple).

An attenuator 15 is used to attenuate the total light flux. A gamma corrector 8 serves to adjust the contrast of the image on the kinescope 9.

Negative for LPM 4 is illuminated by light source 1, previously coordinated with the transmitting path using the first optical compensation filter 10. Electrical signal of a CRT 6

amplified by video amplifier 7 and transmitted with a predetermined contrast to the kinescope 9. When analyzing the negatives, the polarity of the video signal is inverted. The image is observed from the screen of the kinescope through the second

optical compensation filter 13 and the second block 14 zonal filters.

The alternation frequency of the filters of the second block of 14 zonal filters is selected from the conditions for forming a single color.

during the half frame.

All manipulations on the image are carried out without interfering with the electronic path; only the contrast value is preset (the shape

characteristic curve, which depends on the type of positive material and mode of photographic processing), i.e. the parameters of intensity, color correction are optically regulated and maximally

close to the real colorographic process.

Image quality control is carried out visually. The brightness of the image is regulated by the attenuator 15, the degree of oscillation shows a decrease or increase in exposure time.

The color balance is adjusted by a subtractive color head 11 and the color correction will be the balance values of the negative (slide).

In order to carry out the printing process, it is first necessary to determine the color balance of the positive material to be printed on, and the contrast value under the specified photo processing conditions.

The advantage of the proposed device is the possibility of using black-and-white television devices (CRT and kinescope), which greatly simplifies the circuit and increases reliability. Adjusting the input signal using purely optical methods and reproducing the image in terms of colors corresponding to positive material provides a more reliable approximation to the original.

The device provides analysis for any printing method (subtractive or additive), taking into account the characteristics of each type of photographic material and photo processing. With the help of this device one can, without resorting to making photocopies, get an idea of the end result, © to divide the image quality, the ability to print from this negative to the available positive material, to choose the type of positive material.

In some cases, if necessary, the special color solution can be modeled on the screen. Device

can be applied for a black and white positive process

Claims (1)

A television device for visual color analysis and determination of color-matching parameters for photo printing, comprising a condenser located along the optical axis of the light source, a sequentially arranged tape motion mechanism with photographic film, a lens, a CRT and a video amplifier, as well as a kinescope , characterized in that, in order to improve the accuracy, a weakener is inserted between the light source and the condenser, between the condenser and the tape drive mechanism with photographic film successively placed subtractive color head, the first optical compensation filter and the first block of zonal filters; between the video amplifier and the kinescope — a gamma corrector; and in front of the kinescope screen, the second optical compensator and the second block of zonal filters, the first and second Blocks of zonal light filters are interconnected and connected to the output of the synchronizer and to the synchronous inputs of the CRT and kinescope.