The 'Time & Instantaneous' was a development of the 'Time' which it replaced.

It consists of a single blind with an aperture in it. Pulling a cord draws up the blind, a cog wheel at the top of the shutter is caused to rotate and locks against the release arm when set. The shutter is released by lifting the release arm, either by pneumatic bulb of finger.

At the bottom of the shutter is a knob to tension the spring. Optionally a ratchet wheel would indicate the speed that has been set. If this was not fitted then an ivory disc showed the approximate speed for the number of turns of the tensioning knob. Later models always had the ratchet indicator.

The shutter was fitted either on the front of the lens or behind the lens. Several sizes were made up to a lens opening of 5", a rubber grip was used for intermediate sizes.

An aluminium model was produced in the smaller sizes in 1898. This was optionally fitted with the speed indicator.

T-P Roller-Blind shutters

Shutter Models

The shutter is normally tensioned by pulling a cord at the bottom of the shutter, this turns the upper roller. On the end of the roller is a pinion that operates a cog-type setting wheel on the outside of the case which was held by the release arm. On some models, such as the Snap-shot, there was no cog wheel, the upper roller turned a disc with indentations which were engaged by the release arm.

Variations

These mainly apply to the Time and T&I models.

Setting Wheel

In 1903 the setting cord was optionally made retractable after setting.

Release Arm

The image above far right shows a model fitted with a straight release arm, the middle image shows the modified release arm with projecting piece, the last image shows a late setting wheel.

Speed indicator

Joints and Finish

The polish on the wood becomes noticeably red around 1914/1918 and later has a very high gloss. The brass parts on late examples are also more highly polished prior to being lacquered.

The image on the far right shows the fine finger joints, the second image shows the later thick finger joints and a transfer name plaque.

Name Plaque

Position

Safety Blind

Accessories

Rubber lens grips were introduced around 1890.

A Regulating Fan was available from 1890 giving exposure down to ½ second. It fitted along the top of the shutter and impeded rotation of the roller.

A Time valve fitting in the pneumatic release tube was available in 1898 giving exposures down to 3 seconds.

In 1904 a 'Compressor' was available for use with the Time valve, it comprised a metal wedge that fitted around the pneumatic release to standardise the volume of air pushed into the Time valve.