A colleague once said in a discussion: "A translator is someone who looks up a new word in the dictionary, finds five alternatives and takes the sixth." Of course it's not always like that - no translator could do without shelves full of works of reference. But a translator must treat the material that is offered critically - and sometimes creatively.

Gibberish out of the dictionary?

Even good bilingual dictionaries must be treated with caution. An equivalent that is right in one context may be ungainly or even misleading in my present text. Some examples: 

Angebot = offer (???)
The first translation of "Angebot" is usually "offer", and a "Sonderangebot" is definitely a special offer. But a business "quotation", "bid" or "proposal" with specifications and prices for a new project is also called an "Angebot". "Angebot" can refer to the range of books, CDs, videos, reading rooms and films offered by a library or media centre. Here we might speak of the "range of materials and facilities offered".
Some time ago I translated a project proposal for a media centre. The word "Angebot" was used frequently in the German original, but it meant a number of different things. I counted at least ten different meanings - with different translations. Woe betide any translator who always uses only the first dictionary equivalent ("offer").

vicar = Vikar (???)
This mistake is not from a dictionary - I noticed it in TV films. In the synchronised German version of the Miss Marple filmy, Miss Marple speaks of "Herr Vikar", but the person in question is close to retiring age. In fact, the German word "Vikar" is the term for a curate, i.e. a minister in his first trainee post after his course of theological studies. The English "vicar" would be better rendered as "Pastor".

Konstruktion = construction (???)
The English "construction" usually refers to the process of construction itself, not the previous planning and design work etc. The German "Konstruktion" usually (but not always) refers to the planning and implementation of the design.
Depending on the context and usage in individual cases, various equivalents are possible, e.g.
structural design / design structure / structure / design / system / unit / framework / planning / engineering / sometimes even construction. 

sowie = as well as (???)
Strictly speaking, this equivalent is right. But it is used again and again in commercial texts, and usually it simply adds a little variety to the inevitable lists. But the English phrase is fairly rare. In most cases it is better to "translate" the German "sowie" by a comma. In many cases it would be better to break up the long recitation into a bulleted list.

From the translator's workshop

Every translator comes across words which do not have an easy equivalent in dictionaries. The only solution is research, and often a creative turn of phrase. Some examples: 

Band des Bundes
A short term used for a complex of new buildings in the government district in Berlin. The new projects (Federal Chancellery, Chancellery Garden, Forum, Alsenblock, Luisenblock) form a line north of the Reichstag. After poring over the site maps, my solution was: "ribbon of government buildings". 

Auslobung / Auslober
These terms were in the tender documents for a hotel construction project, and I did not find any satisfactory solution in dictionaries. Dictionary suggestions such as "promise a reward" (used in police investigations) were no help in my context. By Internet research and comparison with German legal texts, I then found similar tender documents from Britain. These texts led me to the following solutions:
Auslobung = prize competition,  Auslober = promoter

Spannungsfeld
Various dictionaries suggest equivalents such as stress field, electric field, area of tension or area of conflict. But the word is often found in contexts in which all of these terms are unsatisfactory. Alternatives from practical translation work include: 
conflicting priorities / combining of two opposite ideals / tense relationship / dynamic relationship / situation of conflicting forces.

Such examples show that the translator must always be critical of his/her reference works to prevent the translation from being questionable in style or misleading in content.