Glass plates
We shall consider that collotype on glass is the most practical. It ensues from simple observations which we can doing during visit of studios still […]
The picture factory
An engraving workshop is a working atmosphere. When we change it, it happens that the engraving also changes. Edda Renouf says that her engraved line […]
Summary of the technique
The collotype is a printing process in fat ink, the main characteristic of which is its possibility of reproducing images in halftone without weft, what […]
Gelatin reticulation
The réticulation occurs all the times when the gelatin, inflated by the water, until occupy a volume upper to the one that it occupied during […]
Photographic films
Digital negative : Negatives for collotype can be realized from digital images by printing ink jet on transparent film, without quality loss to compared with […]
Density of negatives
Densitometric balance of films : Ideally, the densitometric balance of negatives for collotype is situated in an interval of densities included between 1,00 and 1,20. It […]
The retouch of silver negatives
The retouch of films is not compulsory. It intervenes for particular works or when we want to obtain certain effects on the images. Film silhouetting […]
Observation on the density of negatives
From a workshop to the other one, the reference density of negatives (I indicate here between 1,10 and 1,20) can vary. This is of in […]
Clarification of negatives
PURPOSE (concern argentic negatives) : to clear up the blacks of the movie to give of the detail in the clear parts of the image […]
Properties of negatives
The main rule concerning the photographic negatives is that should have a well-balanced contrast, of a density situated 1,00 and 1,10. This value is identical […]