The pioneer manufacturers of lamination film in China.


by:Top-In     2020-08-01
Alan Greenson
1976 this is a digital version of an article from The Times Print Archive, before it starts online in 1996.
To keep these articles as they appear initially, the Times will not change, edit, or update them.
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When fluorescent lighting is the main light source, Phttographers taking pictures indoors with transparent color film are often troubled by the difficulty of trying to obtain a natural color reproduction.
In most cases, thi.
Processed color transparent film (slides)
It\'s going to be dominated by a Wikipedia: blue and green tones, destroying what could have been a good set of photos. (
It should be noted here that this problem rarely bothers photographers to use color negatives, because in this case, the required color correction can be performed during the color? ? process.
His discussion will therefore be limited to corrective actions that photographers can take when dealing with positive or transparent films of various sizes. ).
There are many ways for photographers to overcome the obstacles of working under fluorescence, each with its advantages and limitations.
One solution may be to use an electronic flash on the camera or on the camera, as these devices can produce pleasing results on daylight-balance film.
However, a wide-angle photo needs to take the whole area or background, not just the limited area covered by a single flash unit, and any area not fully covered by the flash will still have the blue and green tones mentioned above.
Same thing if you use supplements
1 incandescent lamp or tungsten halogen lamp to overcome the influence of ambient fluorescent lighting.
In both cases, it is time consuming to illuminate an area with this extra device, need to ship fragile, expensive items, and often bulkyAdvertisementAllen Green is onelighting gear.
On the positive side, however, it can be said that, in any case, increasing the existing light level will allow a shorter exposure or a smaller lens aperture to achieve a greater depth of field.
An easier way to deal with the \"fluorescent lighting problem\" is to use a color correction filter on the camera\'s lens to produce a naturally rendered slide.
At this point, it would be helpful to understand why a person would get such a bad color under a fluorescent lamp.
Only a few exceptions (
More information about them)
The light produced by the average fluorescent tube is almost completely inadequate in the red part of the white spectrum.
When we see an area illuminated by fluorescent lights, our eyes make up for the lack of light sources, we barely notice it, but when we see the transparency lens under these conditions, we realize that something must have been missed in order to produce such a result.
Because we can\'t add color to the light at the light source, we have to correct the color of the light before the light reaches the film in order to get the ideal color balance from the light.
Everyone may have a slightly different concept of ideal color balance, but I feel that if I can produce transparency under a fluorescent lamp, it looks like it was taken under noon daylight conditions of daylight balance (
Kelvin is about 5500 degrees)
Then I did a good job.
This is assuming that you are not looking for a special color effect of some form.
A long-term experiment with color correction filters made me find that magneta CC filters with a strength of 50 Wratten units (
More often designated as simple CC 50 M)
Made the balance I was looking for in the high speed ektach Roman daylight movie.
For other lotions, the amount of filtration needs to be reduced.
Using the CC 50 m filter needs to stop increasing exposure so that in the case of high-speed Ektachrome during the day, the photographer is filming a movie with a reduced effective speed from normal ASA 160 to ASA 80.
This filter works beautifully with fluorescent lamps designated as \"cool white\", and practical experience tells me that the vast majority of tubes used today fall into this category.
As mentioned earlier, there are several exceptions to the fluorescent lamp problem.
Duro-test manufactures two fluorescent tubes, and their light emission is ideal for color photography without filters.
The first is called \"Vita Lite\", which gives out a real solar spectrum and is perfect for all movies that are balanced during the day.
Another fluorescence of the company, designated as \"optima-32\", can be used for indoor B-type color films balanced by 3200-degree Kelvin light sources.
There is no need to filter here.
Although compared to the more commonly used \"cool white\" tubes, these fluorescent lamps are only found in a small number of devices and, where possible, it is a good idea to check the lamps before using them. . .
Magenta filter.
Alternatively, if the photographer has the option, install these tubes in the position of the normal tube.
Under fluorescent lamps, the main limitation of color correction filtering is that even with high-speed color film, the effective film speed is reduced to the level where a fast lens is required and only medium or rather slow shutter speed can be used.
Exposed for 1/60 seconds at f2.
In a well-lit office or industrial environment, the average speed of high-speed Ektachrome is 8.
If the photographer wants to use a smaller lens aperture for a larger depth of field, it is recommended to use a tripod.
Of course, the film may be \"pushed \"(
Specially developed)
Produce a higher effective ASA during custom color lab processing. (
One-Stop push will restore the loss of movie speed caused by using the CC 50 m filter. )
Generally judge the effectiveness of any filter in color photography by looking at the skin color in the finished transparency.
Some photographers may prefer to use a slightly less magenta filter.
It could be 40 or 30.
It should also be noted that when shooting in an area with a large amount of light passing through a neighboring window to supplement the fluorescent light source, magenta filtering should be reduced by about 20 unitsfrom (for example)
CC 50 m to CC 30 m.
The advertising filter itself has gelatin form and the usual round glass frame or size mounting that can hold almost any lens.
Many manufacturers make brackets for the filter gel installed in front of the lens.
These gelatin filters are usually 3 inch square and relatively cheap (about $3)
But they are easily scratched. More costly (about $20)
, But more permanent and easier to use is the glass filter of the required strength, which can be mounted directly in front of the lens using a thread or filter holding ring.
The magenta filter I described is available from Eastman Kodak (gelatin)and Tiffen (glass)
But the average photo dealer is rarely in stock.
More common in camera stores are \"f-d\" or \"f-B\" filters that are designed to provide general for fluorescent lighting problems when used with daylight or tungsten film
I find these are just a little helpful, not as effective as using the proper magenta filter.
Most photo dealers can order magenta filters from manufacturers to meet ycrar\'s needs.
It may take weeks, but it is worth buying and waiting.
Fortunately, most camera manufacturers design their lenses with normal front threads or bayonet sizes, which reduces the cost of t orders, when T finally decides to use CC 50 m,
CC 30 M for day replenishment)
As ideal for shooting under fluorescent lighting, I ordered filters of all sizes from Demen to fit all my cameras.
As a working photographer, I also keep a gel holder as a backup to use it to keep a wide variety of filter gels that I keep in a variety of situations where color filtering is required
In the Candlelight light source, it is also possible to provide lighting together with the fluorescent lamp.
Unless the LED light is provided by incandescent equipment (
Balanced movies should be used in this case)
, It is best to continue to use the solar film and magenta filter.
All that happens is that those areas that receive a strong incandescent lamp, such as spots or table lamps installed in the ceiling, will be slightly warmer in the finished slides.
Another advantage of the \"natural\" method of photography under fluorescent lamps is this fixture.
It is almost always installed on the ceiling and provides very soft, shadowless light.
This lighting is usually flattering for people, helping to keep the contrast of the scene within the file capabilities of the movie being used.
A version of the file was printed on page 110 of the New York edition on September 12, 1976 with the title: camera view.
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