H. Hughes & Son Collimator Binocular Mk II (View 5)
In 1934 the British Mk II and Mk III collimators were modified to become the Mk IV collimator by replacing the base with a longer one in order to accept the Bino.Prism No. 5 7X50. A Mk IV collimator from another collection is shown above. It is not known if it was made by H. Hughes & Sons. Note that the Mk IV's "telescope unit" is screwed down at the far left end of the mounting plate for collimation of 7X50 binoculars but that the plate is recessed to allow the unit to be placed in a forward position for collimation of 6X No. 2, 3 and 4 binoculars as explained in the instructions pasted on the lid of the box. Also note that the "Long Binocular Support" which should be used when collimating a No. 5 7X50 binocular is stored in the upper right corner of box while a much shorter support (either a No. 1 or 2) for a smaller binocular is inappropriately installed in the middle of the collimator. A separate device was needed for clamping the binocular to the support which is either hidden from view or missing. If missing, it may have been stored in the compartment at the bottom right of box.
H. Hughes & Son Collimator Binocular Mk II (View 5)
In 1934 the British Mk II and Mk III collimators were modified to become the Mk IV collimator by replacing the base with a longer one in order to accept the Bino.Prism No. 5 7X50. A Mk IV collimator from another collection is shown above. It is not known if it was made by H. Hughes & Sons. Note that the Mk IV's "telescope unit" is screwed down at the far left end of the mounting plate for collimation of 7X50 binoculars but that the plate is recessed to allow the unit to be placed in a forward position for collimation of 6X No. 2, 3 and 4 binoculars as explained in the instructions pasted on the lid of the box. Also note that the "Long Binocular Support" which should be used when collimating a No. 5 7X50 binocular is stored in the upper right corner of box while a much shorter support (either a No. 1 or 2) for a smaller binocular is inappropriately installed in the middle of the collimator. A separate device was needed for clamping the binocular to the support which is either hidden from view or missing. If missing, it may have been stored in the compartment at the bottom right of box.