Vietnam or Thailand ? Vote for the TOP Country of the Week !
But astronomical photography really owes its beginning to De la Rue, who used the collodion process for the moon in 1853, and constructed the Kew photoheliograph in 1857, from which date these instruments have been multiplied, and have given us an accurate record of the sun's surface. Gelatine dry plates were first used by Huggins in 1876.
The use of the collodion is to furnish a delicate, homogeneous, adhesive, colorless layer in which the iodide may be deposited. Its organic nature may favor the action of light upon the iodide of silver. While we have been talking and waiting, the process just described has been going on, and we are now ready to take the glass plate out of the nitrate-of-silver bath.
Kennedy made some efforts to preserve the forged order which he had restored with the collodion, but I could see that he placed no great importance upon its possession. Gradually the yard of the studio had cleared of the employees, who had returned to their various tasks.
Woodbury in his experiments on the Photo-Filigrane process, and confirmed by some trials which we have made. It must be confessed that roller slide experiments which we have made with sensitive films supported on gelatine sheets, or on such composite sheets as the alternate rubber and collodion pellicle of Mr.
Then from time to time mechanical ingenuity added fresh details of improvement. It was found that pieces of hardened tissue of extreme delicacy can be made better subject to manipulation by being impregnated with collodion or celloidine and embedded in paraffine.
It was also thought that gun-cotton of a high degree of nitration when made into colloidal form would even then burn too quickly to be suitable for use in firearms. Consequently, the first experiments were with low grade gun-cotton, what is called collodion cotton, such as is employed in the manufacture of celluloid.
"Nevertheless, to satisfy Maston," resumed the president, "I may tell him that one of our fellow-citizens may be annexed to the study of the celluosity, for collodion, which is one of the principal agents in photography, is simply pyroxyle dissolved in ether to which alcohol has been added, and it was discovered by Maynard, then a medical student."
The making of a really good transparency is by no means an easy or pleasant task with a wet collodion plate, but with these dry plates an amateur can, with a little practice, produce comfortably slides quite equal to those procurable from professional makers.
That, in the fume-laden air of the vault there are always fumes in spite of the best ventilation system made caused the first big blast and started all the damage." Mackay had rejoined us in time to hear the explanation. "Ingenious," he murmured. "As ingenious as the methods used to murder the girl and her director." Breathless, Wagnalls returned with the collodion.
One afternoon Harsanyi, after the lesson, was standing by the window putting some collodion on a cracked finger, and Thea was at the piano trying over "Die Lorelei" which he had given her last week to practice. It was scarcely a song which a singing master would have given her, but he had his own reasons. How she sang it mattered only to him and to her.
Word Of The Day