New York — In 1981, the Celanese Corporation sent its stockholders an annual report that was 66 pages long. The report was glossy, and filled with glowing descriptions of how the company was ''investing for the future.''
This year the gloss is gone, and shareholders received a 32-page annual report that stuck to the basics, describing the company's businesses as they coped with the recession.
By slicing the annual report by 50 percent, a spokesman says, Celanese saved ''a substantial amount of money.''
Celanese is not unique. As the post office delivers annual reports around the country this spring, investors will notice some significant changes.
* Corporations have sliced the budgets for their annual reports. For example, rather than include large, glossy color pictures, they are turning to black and white prints. As William P. Dunk, a consultant at William Dunk Partners Inc. quips, ''They are black and white and read all over.''
Still others - like Amax Inc., the mining company based in Greenwich, Conn. - have totally eliminated photographs. ''It's an austerity annual report,'' a spokesman says.
Amax, which reported a $390 million loss in 1982, notes that by reducing the size of the annual report, ''you save on postage - since it's lighter - as well as on printing and design work.''
Also, there are no photographer's fees, which can run as high as $1,500 a day. ''Photographs can run as much as 20 to 25 percent of the cost of the annual report,'' says an Amax spokesman.
* In their letters to shareholders, corporations are stressing how much they have ''tightened up,'' or streamlined. In an annual report, which had only black and white photos, PPG Industries Inc., a Pittsburgh-based manufacturer, told its shareholders that its cost-reduction program would result in ''a more streamlined organization.''
Or, as Armco Inc., the Middletown, Ohio, steel producer emblazoned on the cover of its black and white annual report, ''We are managing in these adverse times so as to create a stronger company for the years to come.''
Such ''straight talk,'' says Leslie Segal, a principal at Corporate Annual Reports Inc., an annual-report design and consulting firm, is healthy. ''It's telling the shareholders what's happened and what tough decisions we are making.''
Last year, Mobil Corporation talked about its ''bright future.'' This year, with oil prices down and profits sliding, it focuses on ''seeking out opportunities,'' such as reorganizing the company's management. Under the heading ''Finding Opportunities,'' Mobil talks about how closing some less efficient refineries and consolidating some other operations will make the company competitively stronger.
Mobil wasn't the only oil company that scaled down its annual report. Texaco lopped 16 pages off its annual, and Exxon scaled down its use of photographs and chopped off eight pages.
Not everyone in the oil business took the plain Jane option. Mr. Segal says one client, the oil service company Anglo Energy, didn't ''want to look poor.'' But it wanted to spend only 50 percent of its prior year's budget. Through the design process, Mr. Segal says, it was able to meld some full-color photos into a book that cost 50 percent less.
* Some companies are highlighting the high-technology aspects of their corporations. ITT, for example, focused on the most important high-tech development in five different parts of the company. And, TRW Inc. featured many technologies developed for the space shuttle that had been adapted for use in the home.
''Those companies involved in high technology are trying to emphasize this aspect constantly in their annual reports,'' comments Albert Ross, executive vice-president of Shareholder Graphics, a firm that designs and produces annual reports.
* Many companies have been using the impact of deregulation as a theme. Mr. Dunk notes that Continental Telecom Inc. has focused on the Justice Department's antitrust settlement with AT&T. Contel, which used to be known mainly as a telephone company, has used the annual report to present itself as more of an information and communications business.
The report produced by Western Electric, which is part of AT&T, warns potential entrants into its business territory that,''The fact is that we are the formidable competition, and we intend to stay that way.''
* Many companies are using a new way of accounting for foreign-exchange swings. They have shifted to the newly established Financial Accounting Standard No. 52.
Under the new rule, companies use exchange rates in effect at the end of the fiscal year to translate their foreign subsidiaries' assets and liabilities into dollars. The gains or losses that result from this process then are shown in the shareholder's equity section of the balance sheet. In the past, these gains and losses were eventually included in the income statement. For some companies, this accounting change made a significant impact on their earnings. Scovill Manufacturing considered the change important enough, Mr. Segal says, to include a full-page explanation.
Even though many companies have shaved the size of their annual report, most maintain they have included the same amount of financial information. However, instead of providing the shareholder with five years of financial information, Celanese offers shareholders only two or three years of statistics.
These reductions in the size and content of the reports are not universally popular with shareholders - even though the cuts are saving the company money. Lewis D. Gilbert, who heads up an organization called ''Corporate Democracy Inc. , '' disapproves. ''We like informative annual reports,'' he says. ''We also like the increasing number of companies who are including the 10-K in their annual report. This will give them big savings, since they don't have to print two copies.''