How to identify old photos

Collectors can identify their works through the aging phenomenon on the surface of photos, the seal on the back, the back printing of photographic paper and other intuitive ways.

Basic tools for distinguishing works

1. Magnifier: To make a correct judgment on a work, it is best to look at the surface of the photo carefully. Magnifier of 30 to 100 times is an essential tool for in-depth inspection. We can not only carefully survey the details of the work, but also judge the production process, signature method, creation year and other contents of the photo through high magnification.

2. Black light: Black light allows collectors to see things that can't be seen in normal sunlight. Black light lies outside the visible spectrum of human vision, which means that it cannot be seen by human naked eyes. Black light is mostly used for the inspection of coins, and it is also suitable for identifying the paper of photographic works. Many manufacturers began to add fluorescent brighteners and other new chemicals to their products. Fluorescent whitening agent is an invisible dye, which will emit bright fluorescence under ultraviolet irradiation. If an old photo in your collection glows brightly under a black light, it may be made in modern times.

The most direct identification method

When we collect an old photo, we can make a preliminary judgment through some intuitive observations. For example, a silver salt photo, if the edge appears "silver", is likely to be made 50 years ago. If there is a stamp on the back of a news photo (stamps are used by magazines and news agencies), we can get a lot of information through stamps, such as who is the photographer? Which magazine was the photo taken? Although stamps or labels themselves can't completely verify a photo (stamps are rarely forged), they help collectors make their first judgment. Through different brands of photographic paper, it is very helpful for us to understand the production age of the works. Some photographic papers are printed with the manufacturer's name. Although there are nearly 100 different brands of photographic paper for many years, we can trace back the general or specific production age through some common brands.

Identify works through production methods

There are many techniques in the production of photographic works, and the production of techniques is closely related to social development. Early photographic works will be made on glass, silver, tin and other media, so I won't introduce them too much here. Although there are many kinds of photography techniques and photos, calendars

More than 99% of the old paper photos in history belong to the following three types: protein photos:1the most common photos in the 9th century. Gelatin silver salt photos, the most popular black and white photos in the 20th century. C-print or color coupler processes photos, true color photos from the late 20th century to the present.

Discrimination of two special photographic works

Stereo photo is an indispensable choice for many new photographers. They are easy to store and can be used to watch three-dimensional images through special glasses. Stereo photo consists of two framed photos, which were mostly used in 1950s and 1930s of 19. It was a form of family entertainment for a long time before the birth of television and radio. Business card photos are usually called CDV(Cartes de visite is French for "business card"), and protein photos are usually used, although photos of other processes, including gelatin silver salt photos, were also used later. 65438+ In 1950s and 1960s, photos of protein were usually pasted on thin paper plates, and the paper was white, grayish white or light cream. Since the early 1970s of 19, paper holders have rounded corners and more.

The color of. By 19 in the mid-1970s, gold plating and bevel edge were adopted. In the 1980s of 19, dark colors were more common, and the edges of cardboard often had rounded teeth.

I hope the answer can help you.