JPH04367847A - Color enlarger - Google Patents

Abstract

PURPOSE:To decide an accurate exposure correction amount by performing test printing once, to drastically reduce the number of test printing times, to record printing data on a recording medium such as a floppy disk, etc., and to reuse the data in the case of extra printing. CONSTITUTION:Three colors sensors 50, 51 and 52 are provided to measure the density of three colors of a printed frame. A controller 26 calculates a color filter value and an exposing time from the density of three colors, and test printing is performed based on the printing data. The controller 26 transmits the printing data to a data printing machine 63 to execute printout so as to refer to the data in the case of deciding the exposure correction amount in regular printing. A floppy disk device 62 is provided to magnetically record the printing data on the floppy disk 65.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in color enlargers.

0002

2. Description of the Related Art A color original image (hereinafter referred to as a print frame) recorded on a color photographic film such as a color negative film is enlarged and projected onto a color paper by a color enlarger, and then printed as a color positive image thereon. During this photo printing process, if the print frame is exposed directly onto color paper, the color of the printed image will vary depending on the characteristics of the color photo film or color paper, the spectral intensity of the printing light source, the color balance of the print frame, etc. The balance will deteriorate and it will not be possible to produce colors that are true to the subject.

Therefore, in subtractive color printing, three color correction filters (hereinafter simply referred to as color filters) are used: a cyan filter, a magenta filter, and a yellow filter. Color correction is performed by adjusting the ratio of light to achieve a good color balance. Also, some of the print frames include overexposed and underexposed images,
For these print frames, it is necessary to adjust the exposure time to achieve appropriate density.

0004

[Problems to be Solved by the Invention] In conventional color enlargers, the operator tests the color filter values and exposure times on the negative in advance, manually sets the data, and repeats test prints several times to obtain the final image. I'm getting a print. Particularly, when producing a large number of print photos from one print frame, such as a group photo for a graduation commemoration or a postcard, careful test printing is required. Therefore, it is necessary to repeat the test print several times, which results in wasted color paper and wasted time.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a color enlarger that can print efficiently by reducing the number of test prints.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides means for measuring the three-color density values of a frame to be printed, and means for calculating color filter values and exposure times from the three-color density values. , means for performing printing exposure using the calculated color filter value and exposure time, and output means for outputting the color filter value and exposure time used for the printing exposure to a printing machine or a display. Furthermore, for reprints etc.
Preferably, the color filter values and exposure times are written to a storage medium, such as a magnetic floppy disk.

Although three color filters may be adjusted, two
It is easier to adjust individual color filters. In this case, the smallest of the three color filter values is set to zero, and the two color filter values are modified accordingly. Further, the reference exposure time is corrected according to the color filter value set to zero, and printing exposure is performed using these corrected print data.

[0008]

[Operation] After setting a print frame on a film carrier, measure the three-color density of this frame. Then, the filter values of the three color filters at the standard exposure time are calculated from the obtained three-color densities using a well-known exposure calculation formula. Next, after replacing the smallest of the three color filter values with zero, the remaining two color filter values are modified, and the reference exposure time is modified together with this. After setting the two color filters, perform a test print using the corrected exposure time. Further, the print data during this test printing is printed out by a printer or the like or displayed on a display. Furthermore, it is stored on a magnetic floppy disk.

After the test print is developed, the finished state of the test print is observed, and if the test print result is unsatisfactory, the exposure correction amount is determined and inputted with reference to the output print data. Then, new print data is calculated taking this exposure correction amount into consideration,
Based on this, test printing is performed again. If the test print is found to be good, then the actual print is performed based on the exposure correction amount at this time. In this way, since the exposure correction amount is determined by matching the finished result of the test print with the print data of this test print, the number of test prints can be significantly reduced and color enlargement can be performed efficiently. be able to.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS The color enlarger shown in FIG. 2 is used in a dark room, and consists of an enlarger body 2 and a control box 3. In the enlarger main body 2, a base plate 10 is arranged on a disk 9, and a color paper 12 is set on the base plate 10 via an easel mask 11. The color paper 11 is stored in a roll in a magazine 13, cut into a predetermined length by a cutter device 14, and discharged onto the base plate 10 from a discharge port 15. As is well known, the cutter device 14 includes a pair of pull-out rollers and a cutter. Then, by the cut signal from the controller 26 provided in the control box 3,
The strip-shaped color paper from the magazine 13 is cut into narrow strip-shaped test paper 16 during test printing, and into product-sized length color paper 12 during main printing.

A column 20 having a substantially U-shaped cross section is fixed to the center of the rear side of the disk 9.
A guide rod 21 and a threaded rod 22 are arranged inside. A head 2a is attached to the support column 20 so as to be movable up and down. As shown in FIG. 1, a threaded rod 22 is provided inside the head 2a.
A female threaded portion 24 is provided, which is screwed into the female threaded portion 24, and a motor 25 is connected to this. The motor 25 is a driver 25
The threaded rod 22 is rotated by a predetermined amount in response to a print magnification signal from the controller 26 via a. As a result, the head 2a is stopped at a predetermined position on the support column 20 via the female screw portion 24, so that a desired print magnification is set.

As shown in FIG. 1, the head 2a includes a lamp 30, a filter adjustment section 31, a shutter drive section 32,
A diffusion box 33, a film carrier 34, and a printing lens 35 are arranged. The filter adjustment section 31 inserts two of a cyan filter 37, a magenta filter 38, and a yellow filter 39 into the printing optical path 41 according to the filter values of each color, and also inserts these color filters into the optical path 41 during photometry of print frames. Evacuate from within. The shutter drive section 32 retreats the shutter 40 from the printing optical path 41 based on a control signal from the controller 26, and prints and exposes the print frame onto the color paper 12 or 16 for a predetermined exposure time.

The diffusion box 33 extends the printing optical path 41 by 90
At the same time, the printing light that has passed through the color filters 37 to 39 is uniformly diffused. The printing light from the diffusion box 33 illuminates the print frames of the negative film 42 set on the film carrier 34. film carrier 3
4 holds the negative film 42 and inserts it into the insertion slot 44.
It is taken in and taken out from.

The printed lens 35 is attached to a lens board 45. A bellows 46 and a threaded rod 47 for adjusting focus are attached to the lens board 45. The threaded rod 47 is connected to a motor (not shown), and focus adjustment is performed by rotation of the motor. Further, a focus adjustment knob 48 is linked to the threaded rod 47, and by rotating this, the focus can be adjusted manually.

A red sensor 50, a green sensor 51, and a blue sensor 52 are arranged within the head 2a to measure the three-color density of a print frame. Each of these sensors 50
52 photoelectrically converts the light transmitted through the print frame and sends the output signal to the preamplifier 53. This preamp 5
The signal amplified in step 3 is sent to A of the control box 2a.
The signal is sent to the /D converter 54, where it is digitally converted, and then taken into the controller 26. controller 2
6, as is well known, is composed of a microcomputer, and includes a CPU, ROM, RAM, I/O interface, and power supply section 59, as well as a keyboard 60,
A display 61, a floppy disk device 62, and a data printing machine 63 are connected.

The controller 26 calculates an approximate density value (hereinafter simply referred to as density value) by logarithmically converting the reciprocal of the measured value, and writes this into the RAM. A known exposure amount calculation formula is written in the ROM, and is used to calculate the exposure amount for each color. Furthermore, based on a calibration curve written in a well-known look-up table memory, under a predetermined reference exposure time,
Three color filter values, which are the set positions of color filters 37 to 39, are determined from the exposure amount of each color.

Although the set positions of the three color filters 37 to 39 may be adjusted according to the three color filter values, this is done in order to simplify the driving of the color filters and to correct incorrect absorption of the color filters. Therefore, in this embodiment, two color filters are driven to adjust the intensity of the printing light and the color balance. Therefore, the controller 26 replaces the one with the smallest color filter value among the three color filters with zero, modifies the two color filter values accordingly, and then replaces the one with the smallest color filter value with zero. Correct the standard exposure time and
To determine an exposure time such that proper exposure can be obtained when two color filters are used.

As is well known, the keyboard 60 is provided with a density correction key, a color correction key, a mode selection key for specifying a test print mode, a main print mode, a print key, and the like. When the test print mode is selected, the controller 26 performs photometry, calculation of exposure amount, calculation of three color filter values, conversion to two filter values, and correction of the reference exposure time. When the print key is operated, the setting positions of the two color filters are adjusted via the filter adjustment section 31, and after this setting, the shutter drive section 32 is controlled to perform printing exposure.

Furthermore, the controller 26 uses the data printing machine 63 to print out the three color filter values and exposure times used during the test print. FIG. 3 shows an example of this printout. The data to be printed on the paper 64 includes a cyan filter value 70, a magenta filter value 71, a yellow filter value 72, a density correction value 73, an exposure time 74, a print date 75, and an order number 7.
There is a 6th grade. In addition to this, a symbol indicating whether autofocus or manual focus, an aperture value, etc. may be recorded. Furthermore, symbols 77 and 78 such as "T" and "H" indicating whether the data is test print data or main print data may be recorded.

The floppy disk device 62 magnetically records test print data and main print data on a floppy disk 65. This floppy disk 65 is
When ordering extra prints later, data is searched based on print date, order number, etc., the corresponding main print data is read into the controller 26, and based on this, extra prints are performed without performing a test print. be exposed.

The keyboard 60 is used to input various commands as well as exposure correction amounts. The exposure correction amount is determined by the operator based on the finished state of the test paper 16 and the printed test print data. The display 61 displays various key-input data and whether the mode is test print mode or main print mode. The power supply section 59 supplies power to each section, and
The lamp 30 is driven and controlled so that the amount of light is always constant.

Next, the operation of this embodiment will be explained. First of all,
The film carrier 34 holding the negative film 42 is loaded into the head 2a through the insertion opening 44. Next, after turning off the lamp in the dark room, the user operates the mode selection key on the keyboard 60 to put the controller 26 into test print mode. In this state, the controller 26 controls the cutter device 14 to send out the strip-shaped test paper 16 from the discharge port 15. The operator sets the test paper 16 on the easel 11 in a diagonal direction. In this way, by arranging the test paper 16 along the diagonal line, the finished state of almost the entire screen can be accurately predicted by observing the finished state along the diagonal line of the screen even if narrow color paper is used. This allows you to save on color paper.

When the print key is operated, the controller 26 performs a test print. First, three-color sensor 50~
52, the three-color density of the print frame is photometered, and three color filter values for the reference exposure time are calculated based on this. Next, the minimum color filter value is set to zero, the remaining two color filter values are modified, and the reference exposure time is modified. Depending on these two non-zero color filter values, 2
A color filter is set in the printing optical path 41. After this, a test print is performed by opening the shutter 40 based on the corrected exposure time. The test paper 16 after the test print is developed in a paper processor installed in a dark room. In addition, print data such as color filter values and exposure times used during test printing are stored on the data printing machine 6.
3 is printed out on a paper 64 and is also magnetically recorded on a floppy disk 65.

After turning on the lamp in the dark room, the finished test paper 16 is observed to judge whether it is properly finished or not. If the finish is proper, darken the darkroom, operate the keyboard 60,
Select this print mode key. In this main print mode, the controller 26 controls the cutter device 14 to cut the color paper in the magazine 13 to a predetermined length, and discharge the product-sized color paper 12 onto the base plate 10. After setting the color paper 12, the operator operates the print key to perform actual printing. In this actual print, printing exposure is performed using the print data (two color filter values, exposure time) determined in the test print.

If the finish is not proper, refer to the print data such as color filter values and exposure time printed out by the data printing machine 63, determine the optimum exposure correction amount, and operate the keyboard 60. Enter. In this way, the amount of exposure correction is determined by comparing the finished test print with the print data used at the time of printing, so the amount of exposure correction can be determined accurately. After that, a test print is performed again to confirm whether the exposure correction amount is appropriate, and then the main print described above is performed.

Since the test print data and the main print data are also magnetically recorded on the floppy disk 65 by the floppy disk device 62, the test print data can be retrieved by searching for the main print data by order number or print date when making extra prints. The main print can be performed immediately without printing, and printing efficiency can be increased. Moreover, since the same print data is used for printing, it is easy to make the previous print and the extra print the same.

Note that in the above embodiment, the three color sensors 37 to
39 was used to measure the three-color density of the print frame, but in addition to this, an image area sensor consisting of a CCD etc. was used to measure the three-color separation of each point of the print frame to measure color filter values and exposure. You may also ask for time. In addition, this print data etc. can be stored in the floppy disk device 6.
2, the information is recorded on the floppy disk 65, but it may also be recorded on an IC card or the like. Furthermore, the print data of the test print may be displayed on the display 62.

[0028]

[Effects of the Invention] As explained above, according to the present invention,
The exposure amount is calculated based on the photometric value of the print frame, a test print is performed based on this, and the print data such as color filter values and exposure time used during the test print is output to the data printing machine or display. The exposure correction amount can be determined by comparing the results with the print data. Therefore, 1
It is possible to determine an accurate amount of exposure correction in one test print, and the number of test prints can be significantly reduced. In addition, by recording this print data on a recording medium such as a floppy disk, this data can be reused when making additional prints, and the final print of the previously printed photo will be the same as the photo printed when making additional prints. It can be done.

Furthermore, among the three color filter values, the minimum value is replaced with zero, and the remaining two color filter values and exposure time are corrected under this condition. The adjustment becomes easy as it is only necessary to adjust the filter.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a color enlarger embodying the present invention.

FIG. 2 is a perspective view showing the entire color enlarger.

FIG. 3 is an explanatory diagram showing an example of printing out print data.

[Explanation of symbols]

2　Enlarger body 2a head 3 Control box 10 Base plate 12 Color paper 13 Magazine 16 Test paper 61 Display 62 Floppy disk device 63 Data printing machine

Claims (3)

[Claims] [Claim 1] A color enlarger in which a plurality of color filters are installed in and out of a printing optical path and performs color correction by adjusting the amount of filter insertion in accordance with the color filter values, and measures three-color density values of a color original image. means for calculating a color filter value and exposure time from the three color density values; means for performing printing exposure using the calculated color filter value and exposure time; and outputting the color filter value and exposure time used for the printing exposure. A color enlarger characterized in that it is equipped with means for. [Claim 2] In a color enlarger that is provided with a plurality of color filters that can be moved in and out of the printing optical path and performs color correction by adjusting the amount of filter insertion according to the color filter values, the three-color density values of the color original image are measured. means for calculating a color filter value and exposure time from the three color density values; means for performing printing exposure using the calculated color filter value and exposure time; and storing the color filter value and exposure time used for the printing exposure. 1. A color enlarger comprising: means for storing data on a medium. 3. Determine three color filter values according to the exposure amount of each color, set the smallest of these three color filter values to zero, and set two color filter values accordingly. 3. The method according to claim 1, wherein the reference exposure time is corrected in accordance with the color filter value set to zero, and the printing exposure is performed using the corrected color filter value and exposure time. color enlarger.