DE558277C - Red, frosted, electric light bulb for darkroom purposes - Google Patents

Red, frosted, electric light bulb for darkroom purposes

Info

Publication number
DE558277C
DE558277C DEV26570D DEV0026570D DE558277C DE 558277 C DE558277 C DE 558277C DE V26570 D DEV26570 D DE V26570D DE V0026570 D DEV0026570 D DE V0026570D DE 558277 C DE558277 C DE 558277C
Authority
DE
Germany
Prior art keywords
darkroom
red
frosted
purposes
light bulb
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
DEV26570D
Other languages
German (de)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ELECTRICITAETS AG
Ver Gluehlampen & Elec AG
Original Assignee
ELECTRICITAETS AG
Ver Gluehlampen & Elec AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ELECTRICITAETS AG, Ver Gluehlampen & Elec AG filed Critical ELECTRICITAETS AG
Application granted granted Critical
Publication of DE558277C publication Critical patent/DE558277C/en
Expired legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03DAPPARATUS FOR PROCESSING EXPOSED PHOTOGRAPHIC MATERIALS; ACCESSORIES THEREFOR
    • G03D17/00Dark-room arrangements not provided for in the preceding groups; Portable dark-rooms

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Resistance Heating (AREA)

Description

Rote, mattierte, elektrische Glühlampe für Dunkelkammerzwecke Glühlampen mit zwei oder mehreren Glühfäden, weiterhin mattierte und schließlich rotleuchtende Glühlampen sind bekannt.Red, frosted, electric light bulb for darkroom use. Incandescent lamps with two or more filaments, still frosted and finally glowing red Incandescent lamps are known.

Die Erfindung besteht in der Kombination dieser Elemente zu einer rotmattierten, vorzugsweise innenmattierten elektrischen Glühlampe und in der Anwendung derselben für Dunkelkammerzwecke. Die Kombination hat für den angegebenen Zweck besondere Vorteile, und zwar folgende: Beim Arbeiten mit empfindlichen Platten ist es wichtig, daß die Beleuchtung der Dunkelkammer kein Verschleiern der Platte verursacht, und daß dennoch das Sehen gut ist. Es ist eine bekannte Eigenschaft des menschlichen Auges, daß es sich immer der hellsten Oberfläche des Gesichtsfeldes anpaßt. Bei den bisher in Dunkelkammern verwendeten, rotes Licht verbreitenden Glühlampen war der Glühfaden während des Brennens sichtbar und, da das Auge sich an die im Gesichtsfeld (Dunkelkammer) befindliche hellste Oberfläche, also an den Glühfaden, anpaßt, ist es nicht imstande, die in den dunklen Teilen der Kammer befindlichen Gegenstände hinreichend wahrzunehmen, obwohl die Lichtstärke der Lampe schon so groß sein kann, daß empfindliche Platten verschleiert werden.The invention consists in combining these elements into one red-matted, preferably internally-matted electric light bulb and in use same for darkroom purposes. The combination has for the stated purpose special advantages, namely the following: When working with sensitive plates is it is important that the lighting in the darkroom does not obscure the panel, and that sight is still good. It is a well-known quality of the human Eye that it always adapts to the brightest surface of the field of vision. at the incandescent light bulbs previously used in darkrooms The filament is visible during the burning process and as the eye turns to the field of vision (Darkroom) located lightest surface, i.e. to the filament, adapts it is unable to remove the objects located in the dark parts of the chamber to be sufficiently perceived, although the light intensity of the lamp can already be so great, that sensitive plates are obscured.

Der erste Vorteil der erfindungsgemäßen Lampe besteht also darin, daß kein Verschleiern der Platte verursacht wird und daß dabei das Sehen gut ist. Ein weiterer Vorteil der neuen Lampe ist, daß die Beleuchtung der Dunkelkammer den verschiedenen Phasen der Entwicklung anpaßbar ist. Die Lampe kann mit zwei Beleuchtungsstärken benutzt werden, die mit dem Einschalten des entsprechenden Glühfadens hergestellt werden. Wie bekannt, ändert sich die Empfindlichkeit der Platten während der Entwicklung. Bei der Herausnahme der Platten aus den Kassetten müssen die Beleuchtungen minimal sein, um keine Verschleierung zu verursachen.The first advantage of the lamp according to the invention is therefore that no blurring of the plate is caused and that the sight is good. Another advantage of the new lamp is that it illuminates the darkroom adaptable to different phases of development. The lamp can have two illuminance levels are used, which are made when the corresponding filament is switched on will. As is known, the sensitivity of the plates changes during development. When removing the panels from the cassettes, the lighting must be minimal be so as not to cause obfuscation.

Es wäre nun unnötig und unangenehm, während der ganzen Entwicklungszeit mit der gleichen schwachen Beleuchtung zu arbeiten, da die späteren Phasen der Entwicklung eine stärkere Beleuchtung gestatten. Aus diesem Grunde kann man den zweiten Glühfaden einer größeren Beleuchtungsstärke einschalten.It would now be unnecessary and uncomfortable during the entire development period to work with the same dim lighting as the later stages of development allow stronger lighting. Because of this, you can use the second filament switch on at a higher illuminance.

Claims (1)

PATENTANSPRUCH: Rote, mattierte, elektrische Glühlampe für Dunkelkammerzwecke, bei der in an sich bekannter Weise zwei Glühfäden verwendet werden, die zur Erzielung verschiedener Lichtstärken abwechselnd brennen können. PATENT CLAIM: Red, frosted, electric incandescent lamp for darkroom purposes, in which two filaments are used in a manner known per se, which can burn alternately to achieve different light intensities.
DEV26570D 1930-08-28 1931-03-20 Red, frosted, electric light bulb for darkroom purposes Expired DE558277C (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
HU558277X 1930-08-28

Publications (1)

Publication Number Publication Date
DE558277C true DE558277C (en) 1932-09-05

Family

ID=10979615

Family Applications (1)

Application Number Title Priority Date Filing Date
DEV26570D Expired DE558277C (en) 1930-08-28 1931-03-20 Red, frosted, electric light bulb for darkroom purposes

Country Status (1)

Country Link
DE (1) DE558277C (en)

Similar Documents

Publication Publication Date Title
DE558277C (en) Red, frosted, electric light bulb for darkroom purposes
GB266624A (en) Improvements in glareless lamps
DE488873C (en) Electric advertisement lighting
DE482361C (en) Headlight for electric bicycle lanterns with a cover lens consisting of a corrugated glass part and a clear glass part
DE678313C (en) Process for the production of cinematographic recordings in artificial light
DE908160C (en) Mirror for two electrical light sources for generating preferably lateral broad radiation
DE921075C (en) Luminaire used in the casing of vehicles
DE883106C (en) Electric indicator light
AT102132B (en) Device for preventing or reducing the glare of lamps on motor vehicles u. like
DE479972C (en) Lighting device for X-ray rooms to illuminate the lighted room
DE499214C (en) Electric incandescent lamp with two optionally usable light bodies
DE435121C (en) Arrangement for preventing or reducing the afterglow of incandescent lamps for signs with luminous walking text
DE410429C (en) Electric multi-filament light bulb
DE563004C (en) Portable electric light with power source
DE688344C (en) Electric headlight with multicolored light bulb
DE502787C (en) Dimmable headlights for motor vehicles
DE535501C (en) Illuminated sign with discharge tubes
DE817180C (en) Electric light bulb
DE529983C (en) Electric metal wire incandescent lamp
AT100924B (en) Gas-filled electric lamp.
DE469493C (en) Device for lighting vehicles
DE440702C (en) Non-dazzling lamp
AT84010B (en) Device for perfecting artificial lighting.
DE704858C (en) Lamp for indirect lighting
DE454170C (en) Device for colored lighting of fountains