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double extension leather bellows extending at least 18 inches. 
These requisites are usually to be found in the best make of 
cameras now on the market. 
2. Dark Slides. —At least three double backs are required, 
each holding two sensitive plates, and each back should be 
provided with two carriers to take quarter-plates, to enable 
the traveller to use either half or quarter-plates as he may 
desire. 
3. Camera Stand. —The tripod stand should be strong 
and firm, and sufficiently long to enable the photographer 
to work without stooping. The legs should be divided into 
three parts, the lowest of which should slide into the 
middle division. The baseboard of the camera may be 
fitted with a turn-table, but if not, a tripod head is required, 
which should be of as large size as possible, not less than 15 
cm. for the half-plate camera, and have the screw for fixing 
the camera attached to it, as in that made by Thornton- 
Pickard and Co. It is desirable to have an extra screw. 
4. Level. —A double level attached to the camera at a 
place where it can be seen when working is very useful. 
5. Focussing Cloth. —The focussing cloth should be of 
waterproof sheeting or black twill, and should measure at 
least one metre square. It may be lined with yellow 
coloured twill, and should have hooks and eyes attached to 
various parts of its margins, by which it may be fastened 
round the camera, to prevent it from being blown about. 
6. Sliding Shutter. —To enable two views or two portraits 
to be taken on the half or quarter-plate, there should be fitted 
to the back opening of the camera, and flush with it, a sliding 
shutter, in size equal to half that of the opening, which may 
be moved from right to left and vice versa as required, and 
removable at will. 
7. Focussing Scale and View Finder. —It is very useful to 
have a focussing scale fixed to the baseboard, a large view 
finder marked to suit the lenses for half and quarter-plate 
views, and studs for the attachment of a strap, so that the 
camera may be used in the hand if required. 
8. Time and Instantaneous Shutter. —As rapid exposures 
R 
