RAF G45 Gun Camera – advice needed

Thanks Bob.

In the fairing under the access panel on this one…

http://www.bamfbamrs.be/Bamrs/mosquito/mosquito09-10-01.jpg

Can anyone tell me if the G45 was fitted to Mosquito NF variants, and if so, where it was located? Thanks.

i got hold of a g45 magazine over the weekend dont know if there is a film in it if any one is inturested in it

A little more – the lens assembly is same width as the camera body (2″) but is shorter in height to allow for the locating recess in the camera body to engage.
The height of the lens body ‘plate’ is 3 3/8ths and the actual lens is offset on the ‘plate’ – ~3/8ths from the bottom edge and ~13/16ths from the top edge. The diameter of the lens where it ‘flares’ out is the same as the body width (2″).

The centre line of the electrical connector seems to share that of the lens too…

Hope that is clear!

Thanks for the measurements Bob, exactly what I needed. “Old money” is best for these things that were built before we could spell centimetre!

Clocks, thanks too for the link.

Regards,
Derek

DB Design Bureau website – Drawings of Australian aircraft

This site offers a description with dimensions

http://daryl.chin.gc.ca:8001/SEARCH/BASIS/humqa/user/object/DDW?W%3Dinsfull++%3D+%27CANADIAN+WARPLANE+HERITAGE+MUSEUM%27%26M%3D16%26K%3DACSJ004.126.001%26R%3DY%26U%3D1

Some quick measurements in ‘olde money’….
Main body is 9″ x 2″ x 3 9/16″

Lens is a one piece ‘casting’ screwed to the main body and has a base thickness of 5/32″ and total length 2 3/32″
Diameter at front of lens is 1 7/8″
Depth of the lens glass mount is 1/8″

Length of the electrical connector is 1 7/32″
Diameter of electrical connector is 1 3/16″

G45 camera dimensions?

Gents, this is an excellent thread! Fun stuff.

Any change of getting some dimensions for the G45 camera? I’m trying to build a 3D model, and there are lots of pics but so far I haven’t found any dimensional details. Just a length, width and height for the body and diameter of the lens would be fantastic.

Regards,
Derek

Hi Bob

I’ve only briefly read over your thread (my bad habit) and so I may have missed some things that you have already decided on – if so just ignore me!

I’m an electronics engineer, and I too have a (NOS) G45 Camera and so I am glad the poster has put up the AP for it. But it is a project on the back burner for me at the moment.

However I can advise you where to buy a mains powered supply that will run your camera forever without breaking into a sweat, there is no need for a battery really. I can also interpret the electrical stuff for you too if you like.

I also work with CCTV so if there are clarity, frame rate or optical issues I may be able to help. And also I was a wet film photographer for several years – you can probably see why I bought the camera!

I have three cartridges of probably unexposed film which I am worrying may be unstable – some of the early film was nitro-cellulose and prone to self-combustion not surprisingly! I’m torn between safety and chucking some unseen footage, though I can’t imagine that any film wouldn’t have been developed within an hour after landing!

Incidentally there was device that originally put the ‘titles’ on the film from these cartridges on ebay a while ago. I just need more cash and space!!

But happy to help if I can!

James

Hi James 🙂

It is highly unlikely that the three reels of film you have are nitrate if they were intended for use with the gun camera. Nitrate film was only produced in 35mm format, and as gun cameras were operated using 16mm film, I think you are quite safe. You are right to be aware of the risks of nitrate film though, although stored correctly nitrate film will last for many years quite happily. Nitrate does not just “self-combust” willy nilly, it will only self-combust if it is exposed to heat for a prolonged period (this is more of a risk if the film has already starting decomposing). Kept at cool temperatures and looked after properly, some nitrate film is outperforming and outlasting it acetate replacement (Although non-flammable, acetate film can develop what is known as vinegar syndrome, where the film begins to decompose, emitting a strong smell of vinegar).

You mention that you have three cartridges of film – are these in their original boxes? If so it should state on the box the gauge of the film e.g. 16mm. Alternatively you could dig out a ruler and check the width of the gauge 😉

G45

I well remember when these were available (decades ago) in our local surplus stores for a few bob (boxed with mags).
We used to play with them when we were told to leave the Sibe Gorman diving helmets (and boots) alone. (operating the hand pump would bring the man hot-foot down from the till)
A feature of the camera was a heating element visible behind the front lens.
As this would have to be ‘on’ all the time to prevent misting was there a switch in the cockpit to activate the element or was it ‘live’ when the normal Aircraft electrics came on-line.
Later on the same store provided an early ‘bone dome’ (silver) which went on to help a friend to survive a major prang in a fretwork fighter.

Hi Bob

I’ve only briefly read over your thread (my bad habit) and so I may have missed some things that you have already decided on – if so just ignore me!

I’m an electronics engineer, and I too have a (NOS) G45 Camera and so I am glad the poster has put up the AP for it. But it is a project on the back burner for me at the moment.

However I can advise you where to buy a mains powered supply that will run your camera forever without breaking into a sweat, there is no need for a battery really. I can also interpret the electrical stuff for you too if you like.

I also work with CCTV so if there are clarity, frame rate or optical issues I may be able to help. And also I was a wet film photographer for several years – you can probably see why I bought the camera!

I have three cartridges of probably unexposed film which I am worrying may be unstable – some of the early film was nitro-cellulose and prone to self-combustion not surprisingly! I’m torn between safety and chucking some unseen footage, though I can’t imagine that any film wouldn’t have been developed within an hour after landing!

Incidentally there was device that originally put the ‘titles’ on the film from these cartridges on ebay a while ago. I just need more cash and space!!

But happy to help if I can!

James

Hi Bob

I’ve only briefly read over your thread (my bad habit) and so I may have missed some things that you have already decided on – if so just ignore me!

I’m an electronics engineer, and I too have a (NOS) G45 Camera and so thanks to Terry for putting up the AP for it. But it is a project on the back burner for me at the moment.

However I can advise you where to buy a mains powered supply that will run your camera forever without breaking into a sweat, there is no need for a battery really. I can also interpret the electrical stuff for you too if you like.

I also work with CCTV so if there are clarity, frame rate or optical issues I may be able to help. And also I was a wet film photographer for several years – you can probably see why I bought the camera!

I have three cartridges of probably unexposed film which I am worrying may be unstable – some of the early film was nitro-cellulose and prone to self-combustion not surprisingly! I’m torn between safety and chucking some unseen footage, though I can’t imagine that any film wouldn’t have been developed within an hour after landing!

Incidentally there was device that originally put the ‘titles’ on the film from these cartridges on ebay a while ago. I just need more cash and space!!

But happy to help if I can!

James

That’s my image (and blog)…
Cameras were usually positioned in the leading edge of the wing just outboard of the wing root. The Hurricane had them about half way along the wing if my observations have been correct.
I have occasionally observed a strobing effect from the prop but normally the engine RPM is high enough for the prop not to be visible, and that’s after watching gun camera film for over six years!
Clarity was more often affected by poor focus or over exposure – annoying if you’d downed an enemy aircraft only to get back to base to find the camera just recorded a fuzzy mush!!!!

Having done some further research around where on the aircraft the camera would be located am I correct in thinking that the camera shoots through the aircraft prop on some aircraft?

A photo from warbirdskies; http://bp0.blogger.com/_iJ5cudRMyZI/SH46MtVO4UI/AAAAAAAAAD0/k8hOQvtoHU4/s1600/P1030282+copy.jpg

With the prop going round and the camera shooting approx 20 frames per second I wonder if this had much of an impact on the clarity of the moving pictures that were filmed. I imagine that at slower engine power settings you might expect to capture the prop appearing to be standing still? Though you might not be shooting your Gun Camera at idle power very often!

The image in the photo above is a Spitfire and has the camera mounted in the wing root. I notice that other aircraft have the camera further outboard, outside of the arc of the prop.

Any thoughts?

I think the sound of the camera in use would have been drowned out by the engine and guns!!! 🙂

Old cameras are routinely noisy – you should hear some of the springwound beasts as they labour! I’m afraid it’s something you’ll have to put up with.

Be sparing with WD-40. It’s not recommended for cameras etc. as it leaves a residue that eventually dries out and can cause things to stick. There are specialist clock oils out there that will suite your purpose fine in future.

Definitely think some new leader may help.

Today I dismantled the moving parts in the cassette and cleaned all the dirt from them and smoothed them as much as possible and applied some WD40 very sparingly. The film is now able to travel much more easily and the camera appears to function correctly except for an unpleasant sound.

I’m not able to identify the cause of the sound but I’ve been able to video the camera in operation and you can hear the sound……http://m.youtube.com/watch?feature=plcp&v=FFA0REyJw_I

Are you using old film originally in the cassette? I’ve occasionally found very old film to have increased friction due to a breakdown in the emulsion/loss of the lubricating compounds and the plastic base becoming brittle. I have some newer material I’ll send on for free so we can rule this out. PM me with an address and it’ll be in the post friday.

Will look at the videos in a bit.

Robs

For anyone who may be interested in seeing what I’m up to I’ve filmed my attemps at running the camera in an effort to identify the issue.

To help with this, I’m running the camera on it’s side with the film cassette open.

It runs slightly better with all the hatches fastened as they help to hold the cassette in position but it still has the same issues with the film not being taken up and the friction mechanism designed to rotate the take up reel slipping.

Comments and feedback welcome – I thought about oiling or greasing the moving parts in the cassette but I’m reluctant to just in case I later run it with actual film which may not appreciate oil splashing around!

The link…http://www.youtube.com/watch?v=lCLlsqnDd5o&feature=youtu.be