Parts and build suggestions for a Watec 902H based add-on

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some bloke
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Joined: 27 Jan 2012, 16:14
Location: Cornwall or Leicester

Parts and build suggestions for a Watec 902H based add-on

Post by some bloke » 13 Mar 2013, 17:55

Here are the parts needed to build a Watec 902H 1/2" CCD based add-on / 'Spot - On' night vision rig. ... 53f871344e

This 25mm 1/2" CCD format lens If your scope has a minimum mag of 3~4, You WILL need to use the adaptor spacer ring that comes with it between the camera and the lens: ... 27d2059292

If your scope has a minimum mag of 5~6, the 16mm 1/2" format lens, second down on the list near the bottom of the page, part number MF-MI-16 C will probably serve your needs better: ... -lens.html

There is a lot of confusion with regard to whether the lenses being listed on ebay are C or CS mount formats, even the vendors get that bit wrong sometimes. For the amount it costs PLEASE get one of these, and if you cannot focus your lens to your reticule properly fit this between the camera and the lens: ... 2c6d4902ea
You may need to source a 12volt battery in the UK now though. ... 0790893954

I'd recommend you make it up as an integral combined spotter and add-on rig something like this, alloy, carbon or plastic sheet cam be used in place of the marine ply I used: ... f5f6ff.jpg ... dlamp2.jpg

So you can use it on and off the rifle like this:

A plastic scope adaptor tube would make life easier than my metal one, it needs to be larger than the eye bell diameter of any scope you might use it with, then wrap gaffar tape round your scope eye bell to bring it up to size. Waste pipe might fit your scope or some use empty mastic tubes, pvc tube etc. The openings in the tube are for adjusting the lens focus and iris. A 1" hole saw and hacksaw blade is all you need for that. Wrap gaffar tape around the camera body to bring it up to the diameter needed to become a slide fit into the tube - that will help to keep it correctly aligned during handling.

Combined spotter and add-on:

See the different image sizes and clarity when using this method both on and off the scope, The silent scenes are with the device OFF the scope, being used as a spotter (ignore the crosshair overlaid on it). The scenes with audio are as used ON the scope. Both were taken with 25mm 1/2" format adjustable iris C mount lenses.

The Infra Red Illumination source used in this clip is an Ultrafire 501B P60 type torch with a DIY custom made IR drop-in module and special Ahorton aspheric focussing lens. Suitable for normal rimfire ranges.

Build instructions for the P60 size torch drop-in modules and other larger illuminator options for longer range are discussed in the DIY illumination section of this forum HERE:

All the best, feel free to PM me about anything your not sure of - or start a thread and ask the general membership.