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Robert Hart

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About Robert Hart

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  • Occupation
    1st Assistant Camera
  • Location
    Perth Australia
  1. It is likely you have a short loop. The linked clip is not the be all and end all of how to manage the CP16R but the methods worked for me. There are also some other clips on managing the CP16. After film has been loaded in the CP16 for a while, the upper loop bend and the tight bends around the drive sprocket rollers and the infeed roller become shape-memorised by the film. The signature starting sound of the CP16 may be a smooth run for half a second, then a soft momentary clatter, then two soft momentary clatters and sometimes rarely a third as shape-memory bends momentarily lift the pressure plate which chatters as the claw pulls the film through. If the clattering is continuous, you need to reform the loop. You should only experience this if the film has been in the camera for a long period and even then very rarely. The lower loop on its progression should be almost brushing the black felt acoustic insulation in the bottom of the camera body and barely touching the fixed guide stud below the gate for the loop to be correct. Enjoy your camera. Properly set up and maintained, despite all manner of rumours and folklore to the contrary, the CP16 film transport will pass a double-exposure test as well as a pin-registered 16mm camera.
  2. The screw may have been replaced if an original fell out and was lost. Does your lens's screw have a narrower smooth toe with no threads on its end. It may be that the screw is screwing in but the threads may be interfering with the sides of the squarecut channel and stopping it from sliding back and forth past the screw. If the screw is too long, it may be bottoming out in the squarecut channel and jamming the optical block against the barrel on the opposite side.
  3. This clip is of a test alignment of the blue sensor in its temporary bridge pieces. You'll have to be quick to spot it just after the title. There remains a need for a rotatational adjustment the sensor.
  4. Obviously much finer alignment is needed. The blue margin is a result of the sensor not being quite flat on the prism surface in the lower right corner.
  5. A small update.Here is an illustration of a temporary support for the detached sensor which enabled me to establish just where in space it should be. The next step is to build a different support attaching to two pairs of screws and is microadjustable and yet enables enough clearance that the small dobs of adhesive can be spotted upon the four corners of the sensor to prism junction.The material needs to be viscous so that it does not creep or wick in between the sensor and the prism through capillary action.The adhesive appears to be a non-brittle material similar to white water cleanup bathroom sealer.The bridgepiece is cut from formica or laminex which is a material similar to thermosetting resin or bakelite. It is insulative to avoid any chance of electromagnetic fields being introduced into the original steel jig pieces which function also as heatsinks. EMF seems to have been an issue because magnetic strips have been taped to the ribbon cables.The bridgepieces block airflow so cannot be a permanent solution.The far bridgepiece has been made to be a precise fit to another intact sensor block with three screws. There are elbows in the far jig pieces which have threaded holes which are conveniently are a match to the camera body screws. This cannot be an accurate exemplar because each sensor itself is very slightly different and must be aligned before the adhesive is applied in factory. It does however get very close. The bridgepieces are cut to be a very slight interference fit to the jig pieces.
  6. For those who have the endurance to remain curious, any bridge pieces which are made have to be vented to allow the small fan to push air through. As Tyler has mentioned above, the little processors on the PCBs the sensor chips are mounted to can get hot enough almost immediately to be on the pain threshold. The bridge pieces are best made of formica or laminex sheet which is a thin thermosetting resin similar to bakelite. I have established with these it is possible to get a good alignment but perfection will only come from screw adjustments, not finger pressure and barely tightened screws. Once I have established a position for the loose sensor I will make up different mounts attached to four conveniently located screws on the rear face of the mount to confirm to the restored position of the sens and use that instead of bridging all the sensors together.
  7. If they really have a passion and commitment to this project and are not doing the entitled thing, they will find a way to make the financing happen or find a patron. That patron should not be you unless it pleases you to sponsor the project for the feelgood or "the exposure". When it comes to loyalty down the track from up and comers, you can pretty much assume it will be non-existent if they step on the fast train. Those who hire a new director are not likely to want any attachments which come with him or her.
  8. It seems that it can be done. This phone pic of the LCD screen is of the image from a JVC GY-HD111E with detached blue sensor relocated using rough cardboard bridges made from cereal packet cut with razor blades. Obviously the adjustments would have to be finer before the image on a large display screen would hold up but this is a good start. What a pity I did not do this a few years ago. I might have made a few dollars. Now I am just patching up museum pieces and there is no worth in it.
  9. Tyler. There is a little fan in there but the blue sensor is highest in the group and probably receives more heat due to convection. There is another dynamic in play with the blue sensor in that the ribbon cable is only just long enough and imparts a lot of constant draw tension on the blue sensor board. Over time I suspect this has been the mechanism for the sensor coming off. This can be converted into a pressure load by adding a spacer between the upper surface of the blue channel ribbon cable and the underside of the SD card slot assembly above. Whilst doing a "live test" with the blue sensor bridged on one side to the other sensors and manually adjusting the free edge, I observed that the green sensor, whilst apparently firmly attached can flex very slightly on the adhesive and spring back. I did not try the red sensor. Sleeping dogs are best left to lie undisturbed. When playing around inside a camera with a loose blue sensor with the right casework removed, take care to insulate between the edge of the blue sensor and the green sensor below it. They will short to each other and the camera will go dark. I thought I had destroyed it but it seems that this crashed whatever computer is inside it. When switched off and switched back on again it was fine so I dodged the bullet that time. Phil. The blue sensor coming off, creating a yellowish hue which won't whitebalance out has been a common failure mode with the JVC GY-HD*** camera family. Another failure I have with one of the three cameras I have here which has an intact sensor block is that half of the green channel has faulted leaving a purplish hue on one side. The fault is in the sensor and its downstream connector. The fault carries over to another camera when the block is installed in it. That sensor block is my template for making the bridge pieces. Each sensor block will be individually slightly different because of manufacturing differences between sensors when the imaging chip is first installed. I am hopeful that the differences are so miniscule that simple tapered screw adjustments will enable the pixel rows to line up. The system was accurate enough to enable fine flying head adjustments on the old Sony EIAJ reel to reel video recorders. Shimming was another matter. The adhesive seems to be similar to the water washable white bathroom sealer and is not dead hard but slightly pliant. It cleaned off from both the sensor face and the prism glass like bathroom sealer with a small wooden blade, a cut-down icecream stick. I don't like my chances but I have sent a request to JVC in the US asking what they used for adhesive. It appears that there are only four small points on the corners where there is adhesive in spots of about 1mm at most.
  10. This has been a common failure in this camera family usually manifest firstly with blue rimming on hard contrast edges, becoming a soft and separate ghost blue image or no blue image at all, just a blue moon shape and a yellow cast in the rest of the image which users cannot white-balance. The fix from JVC is to replace the entire sensor block at considerable expense which given the obsolescence of these cameras is not justified. Because of the manufacturing technique and the attachment of the sensors to the prism by adhesive alone with no other mechanical support, alignment of the detached sensor and reglueing it is not an option. However a means of attaching the blue sensor using two bridgepieces from the green and red sensors attached to jig hardware which remains on the individual sensors may be an option. From rough tests it sees doable, the issue being finding space to add small adjustment screws.
  11. Age becomes an issue when there are many kid eagers out there prepared to provide their brand new camera and work for monkey-tucker. Good luck to them with their energy and their ambition. In the meantime once a succession of them have worn themselves and their cameras out subsidising an exploitative industry and a production entity eventually gets burned by a reshoot, us wrinklies will have gone on the dole queue.
  12. The 1/3rd stop light loss may or may not be applicable. It will depend if you are using an original lens set supplied with the camera which has been calibrated to the camera for the numbers on the iris ring to appear "as if" there is no light loss. Lenses from other sources will be that 1/3rd stop underexposed. Better and smarter folk than I may explain this more accurately and and fewer words.
  13. There will be inside the gizzards of the camera, a centrifugal governor of some sort. For sake of smallness, the governor in a Bolex H16 clockwork camera appears to be controlled by friction of small leather boots inside a polished brass bell. The frame rate adjustment sets what rotational speed the friction pads engage the inside of the brass bell. Other industrial or internal combustion engine governors use spring resistance against the centrifugal force and some sort of mechanical linkage to a power controller, usually a throttle lever. What is inside the Bell and Howell I do not know but it will be a centrifugal governor of some kind. If there is any contamination of the friction surfaces in a Bolex, it must be cleaned. Otherwise there will be slight flicking as the governor hunts for correct speed across a wider variation than it should. If there are varying amounts of friction in the whole drive train, this will force the governor to hunt heavily for correct speed. It likely will not overspeed and underexpose, but at tight spots in the drivetrain, speed will drop back and cause your over-exposed frames before the governor can step back to restore speed. It is likely a service is needed which includes cleaning old dried lube off gears and thrust faces, relube and cleaning the governor, which should restore your camera. In the Bolex, a well maintained governor, set against a strobe source whilst the film transport is loaded will hold the camera in sync with a modern sound recorder for about 15 seconds, sometimes more. The Bell and Howell speed control may not be as accurate but there certainly should not be any light frames in each run except at starts and stops. You also need to be decisive when you button on and off. If you relax the trigger slightly, it may drag on the transport and cause your light frames. You also should not allow the spring to entirely run down before you button off. The high speed part of the mechanism may continue to run on under its own inertia and pull the spring end out of its retention. As mentioned above, given the price of the camera, you need to decide the cost benefit of having it fixed. Any other cameras out there which are offered for sale, unless they have been recently serviced, will likely have some speed issues, so my personal preference would be to suck it up and have it serviced. Mechanical devices with plain bearings, gears and springs, do need regular maintenance whether they are being used daily or sleeping on a shelf for six months.Your camera may well have been in hibernation for years. I was not able to hear sound with your video recording. A sound track with the vision might be more helpful. Please heed better advice from other folk.
  14. If you want to go with live display, you could try to defocus the LCD screen by cutting a piece of lighting tracing-paper diffuser to screen size and oiling it with barbecue spray or spraying hair spray on the textured face of the tracing paper to make it more transparent. You may of course still get screen-refresh artifacts. There may be other ways of doing this which are healthier for the LCD display you are putting it on, - oily side not touching the screen of course. You will likely need to use a spray. Wiping or brushing will leave bands and streaks. My personal preference would be to put a paper chromakey green mask on the display and adding the screen vision in post. With older curved CRT displays, it becomes a bit trickier to get a good lay up of a paper mask. I have had adequate but not best results using spray-on contact adhesive on a CRT screen then laying up a piece of carefully precut green pooltable felt cloth which has been lightly pre-sprayed with the same contact adhesive. You need to let the adhesive dry to be as tack-free as possible because you need to interpose a large piece of paper between the cloth and the CRT screen and carefully ease it out as you firm the cloth down to the CRT screen's curved glass surface. You most likely will still have to trim the edges. With care you should be able to "walk" any wrinkles out and not have to lift the cloth. Lifting the cloth will stretch it uncontrollably and you may have to start over. Please take the advice of others with more valid comments to make than mine
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