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Robert Hart

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  • Occupation
    1st Assistant Camera
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    Perth Australia

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  1. Further to my comments above, the light leak looks like normal edge flaring from light passing into the gap of a daylight spool because after a while it goes away. If you inspect the film by eyeballing the film itself, you may observe similar leak flares on the sprocket side of the film. Another cause of variation of focus may be the three lens turret if you camera has one not being locked down. From memory, there should be a little dummy plug which screws into the body through the upper lens hole. If that is not fitted or loose, a heavy lens may droop downwards slightly and cause varying focus between the upper edge and lower edge. Gently lift the front of the lens and check that the turret disk is not moving, closing and opening a thin gap at the top between the turret disk and the front of the camera body. If looking through the viewfinder when doing this, you may observe focal shifts.
  2. I second Dom's assessment of the pressure plate. I cannot now remember if the Bolex gate has rails of a flat surface. If there are rails and the extended image side rail has been milled narrower, then the pressure plate is likely to be pressing inwards of the rail edge and bulging the film towards the lens. Another cause may be the edge guides of the gate which hold the film steady from weaving. I cannot recall if they are adjustable. If so, then they may have been set too close to each other and causing the film to cup out of focus and also lift the pressure plate. The momentary increases in the defect suggest that film shape memory from being parked around a sprocket may be lifting the pressure plate slightly higher passing through. From memory, the pressure plate on my RX5 was black plastic and there was considerable clearance between the side rails and the pressure plate edges. The variations may be the film tension through the gate buckling the film a little more until the motion stabilises. I had a bulge problem with a CP16 caused by an edge guide which had become skewed during reassembly after some maintenance. It was never apparent until the first time a shot indoors in low light with fully wide aperture and there it was as plain as day. Lost a critical 100ft roll to it. The light leak may be from two causes : Damage to a little plastic bloop-lamp housing on the bottom right of the camera as viewed from the front. Light passing around the very edge of the shutter disk which may not be of quite wide enough diameter. If the light is rebounding from newly dressed metal in the gate aperture, painting that edge with lens black or a sharpie may be a temporary fix. A fix is realistically the province of a camera tech to sort out.
  3. Pulldown is taking off before the shutter closes. If there is a helical drive gear for the shutter, a thrust washer may have worn allowing the shutter disk to move slightly on the spiral gears and cause the shutter to become late. If your camera is a reflex type, chances are the collimation of the film plane and groundglass viewfinder is also off.
  4. There is Frame Discreet (Manager Justin Lovell) in Toronto for film scanning services. https://www.framediscreet.com/
  5. Is green reflection from lawns and green tint in light through foliage a factor?
  6. My sense is to respect the lenses and have the work done by professionals who know what they are doing. Before I knew their intrinsic worth, I de-fungussed two Speed Panchro Series II lenses. They had been assessed as uneconomic to repair and were a gift. The 50mm was fairly straightforward but one of the internal optics had a little penetration into the glass. The front coating cleaned up well enough. The 75mm was a basket case with small but noticeable scratches on the front element from careless cleaning and one of the internal elements had penetrating fungus erosion of the glass itself. I made a sort of conforming mould and polished the eroded glass with cerium oxide. By more dumb luck than good judgement it worked. On reflection and from reading I have done since, it was something of a minor miracle that I did not destroy the figure of the element. Both lenses ended up flarey, the 75mm more so. Outfits like P+S Technik apparently polish and recoat the glass of the lenses they modernise. This is of course a costly exercise.
  7. If there is extreme governor hunt (jerking) and flashing of highlights during slow pans (lesser surges of speed), chances may be that oil has got onto the little leather governor shoes and may even have become gelled. Their normal operating state is to be completely dry. As the spring winds down and its power diminishes, the normally fine adjustments by the governor may have become coarsened by contaminated shoes momentarily gripping in the bell then being suddenly released as the centrifugal force collapses. The only cure is servicing by a proper camera tech. However please take heed of folk properly knowledged about the Bolex gizzards than I am.
  8. If your drive spring is weary, you may only get about 15 seconds before the frame rate drops off the governor. A quick and dirty method of checking the spring is to load a roll of junk film. set the governor frame rate to whatever your local power supply frequency is, 50Hz for PAL TV countries and 30Hz for the US and many others. Place your camera under an old-school flourescent tube lamp and watch the frame counter dial on the side of the camera. You should be able to just see the marks as they move. They may hold steady or creep. Any speed change will be apparent as the creep forward of backward will alter. You can also take the lens out of the Bolex and through the lens mount opening, view the shutter blade whilst film is pulling through an older-non-reflex camera. The screen light from old-school CRT television sets was also good for checking the camera governor. New LCD televisions/monitors do not flicker as much. If you have a video-camera which has a high shutter speed, you can use that to view the frame counter though a close-up lens/macro by setting the governor to as near to the video frame rate as you can get, ie., 25P, 24P, 30P. I used a similar hack to set the governor speed on a generator. Shooting with the parallax-adjustable side-finder in well lit conditions is not hard but requires the discipline of a mental check list every time you use the camera. As long as you are patient, you can use the eyepiece out of an old pair of binoculars to view the groundglass screen of the upper view port which you use by rotating the lens turret to bring the selected lens into view. Take care to press the lens turret disk rearwards. Sometimes the weight of lenses pulls the turret disk forwards and the focus will then be off. This method is fraught with possibilities to waste film as the lens aperture has to be opened wide for accurate focus and to be able to see anything on the dull groundglass. A few folk have made video-split hacks with small CCTV security cameras, 50mm lens and about ten 5mm CS- to C-Mount spacers stacked behind the 50mm lens and a bodged spacer between the front of the lens and that upper viewport. this means adding wires, power supply and a viewing monitor which rather defeats the agility of the bare camera.
  9. The camera itself most likely needs attention and is a task that only a competent camera tech can undertake with confidence. Any mismatch between the viewed groundglass texture and the film surface will be more apparent with wide-angle lenses. The wider the aperture, the more apparent the focus issue will be. The adjustable eyepiece dioptre itself which enables the eye to focus on the groundglass screen is not the issue. The likely causes of your problem may be :- the position of the textured surface of the groundglass may be incorrect relative to the film plane. the rotating shutter mirror surface may no longer be correctly positioned due to wear of a bearing surface.
  10. For those who are considering going the DIY route, your light will need to be very, very evenly bright across the whole image frame. Inverting a negative image amplifies any deficiencies in the light source. Note the brighter sides and corners in this test where the light from the lamp was slightly less, not apparent in positive scans but amplified by the inversion of the negative.
  11. Might have been a continuity camera. I don't think they were still using Polaroid instant cameras by then.
  12. Electronic components seem to be the achilles heel of many appliances nowadays. For mechanical wearing surfaces, there are some splendidly robust metals available and surface finishing has been a fine art for many years. Modern automotive engine valves often endure the lifetime of the entire car. My money would be on camera sensors becoming obsolete and being upgraded before they actually lay down for the count. Pixels do go hot. Capacitors do age and not in a beautiful way. Electric motors seem to endure for years if the quality is built in. Simple plain oilite bearings and ball bearings so long as they are not drowned by water can go on for years. The film transports of old telecines are enduring long enough for the machines to become rebirthed with modern electronics. Steenbeck flatbeds seem to live forever mechanically and it is perishable stuff like electronics and synthetic cogbelts which bring them low. A few old ones have burned down. In stepping scanners, Intermittent transports may eventually wear enough to go off spec. Maybe this can be adjusted for or replacement parts required. I guess it may depend upon how much any given manufacturer wants to extract revenue from after-sales product support. Finally, any appliance depends upon the care shown by the operator as to how long it will keep running. As to how long a machine wikll keep on going. - that is anyone's guess. There are two basic usage models for any machinery. Drive until it until drops then rebuild/replace or operate it within a regular maintenance schedule and replace parts within their lifetime before they fail.
  13. The little lamphouse is in a different position on the H16RX5. The piece had been destroyed in some past mishap so I cut a small strip of gaffer tape to cover what remained.
  14. This is where the light leak occurred with my old Bolex H16 non-reflex. The light bands only occurred when the film was at rest. During motion there was not enough light leaked in to cause a problem. In daylight outdoors, a timelapse would be likely to be spoiled by banding.
  15. Static electricity when winding film may create more of a visual effect like a variable area sound track as a faint blue stain on prints from neg. My money would be on the following, a light leak where the front assembly fits into the maincase or damage to a small enclosure for a tiny sync lamp in the front of the camera body, lower right as viewed from the front. In regard Dom Jaeger's suggestion, I experienced light leak with an old H16 in those joints at the front after a desperate dismantlement to deal with water entry. My cure was fairly primitive at the time, a thin layer of clear Tarzan's Grip over the seams inside the case, blacked over with a felt tip pen. The leak was very faint and only occurred when the camera was at rest and marked stationary film. It is over 30 years ago so my memory is vague. I think the leak occurs where those seams are exposed by a small clearance where the door overhangs. Whether I was on the right track or not I do not know. Whichever, the problem went away.
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