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Robert Hart

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Everything posted by Robert Hart

  1. I note that no one has yet mentioned an operator trap. That is to make sure you release the loop formers after loading the film. On cameras which have a few miles up, the donkeytraps in the door can be defeated and the loop formers may remain closed if the operator has forgotten to pop the little silver button and the loop formers have not sprung back out. This will also cause the registration issue you describe. I gather you are also aware of the little scissor blade in the bottom of the camera enclosure. Before you autoload the film, you trim the end of the film with it before feeding in to the operating mechanism. when loading it is best to set the camera speed to its slowest.
  2. I understand that the governor bell and its pads need to be dry, not lubricated. Can you confirm or refute that as I only got the info secondhand.
  3. FOOTENOTE: I did a rough and ready offer up of a 0.71x focal reducer to the Bolex RX5. Without some severe modification which would replace the front swinging turret, I doubt you have enough real estate for the 0.71x to work to infinity focus.
  4. There were a couple of Nikon F-Mount adaptors for the CP16R so it could be used with photo-journo's lenses if the zoom lens was damaged. The version I have consists of an F-Mount on front and the CP tail on the rear and a planar glass element which apparently moved the flange face forward optically to make more workspace within the adaptor. The flange faces are 12.5mm separated. Doing the math on the flange to focal plane distances of Nikon F-Mount and CP-Mount, the difference is closer to about 5.7mm which would be insufficient workspace to make everything including the latchpin to fit. A Canon EF-Mount would not be doable as an adaptor without an optical element in it to move the EF-Mount flange face significantly forward. Your solution for the Meteor lens may look rough and ready but definitely does the job. The tails for the CP Ultra T* lenses had an internal diameter of 44.0mm which stepped down to 33.5mm.
  5. The second one is to a 16mm film camera lens and near-to 16mm sized sensor so optically it was probably a better match. The anamorphic lens was in a closer couple with the prime lens as it was handheld in place than with the remachined B and H lens adaptor wich adds about 5mm separation. I may examine making a sleeve mount which will enable a closer couple to the camera lens. this will also enable a more convenient orientation adustment. The Proskar anamorphic lens was designed for 50mm focal length projection lenses for 16mm so may have been a better match for the 16mm format. . As for the cat, there were stray cats hanging around at the time so she was in a state of high tension. She was dangerous to be near when so stressed because she would freak out at the slightest movement nearby and rip into the nearest thing in sight which might be the foot or the leg if it was close handy.
  6. Here is another clip with the Ishico lens to the sensor on a SI2K video camera which is very slightly smaller than a Super16mm film frame. You will observe slight corner vignettes which are not apparent when viewing through a standard 16mm film camera viewfinder.
  7. 2x from a Ishico Proskar anamorphic projection lens with the original B and H lens projector adaptor remachined to 52mm 0.7mm filter thread is doable to some Nikon stills lenses or CP Ultra T* 25mm in standard 16mm - just. You have to remove one of the end stop screws in the Ishico lens to achieve infinity focus as they were set up for limited distance projection throws. The clarity is not anything to write home about. This clip was shot on a 4.6K camera with a Nikon lens. For 16mm film you want the image to be the sharpest and clearest it can possibly be. Homebrew solutions like projection lenses most likely will not work unless you desire a distinctly distressed look.
  8. From vague memory, you would need at least 16mm of workspace between the film plane and the rear of a focal reducer aka speedbooster. You will not find that 16mm of workspace inside a rotating mirror-shutter reflex camera. That workspace is for the Caldwell 0.71x Ultra optical cell which is not ideal for the Super16mm frame. You might just shoehorn it in with a custom assembly replacing the lens turret on a C-Mount Bolex H16RX5. There may be a C-Mount to M4/3 adaptor but the only versions I have found on eBay mount C-Mount lenses into a M4/3 camera, not the other way about so you have to get one made so that a Metabones PL to M4/3 Ultra 0.71x speedbooster could be mounted. The Speedbooster for the original BMPCC would better suit the Super16mm frame optically but has to be even closer to the film plane (6mm) and would not fit in the available workspace of any Bolex as you will interfere with even the upright shutter disk path. The RX5 Bolex has another wrinkle in that the prism path for the viewfinder changes the flange to focal plane distance compared to the Bolex non-reflex older H16 cameras. The in-air flange to focal plane distance may be shorter than when the prism splitter is in the optical path. A 0.71x focal reducer may be most easily fitted if a custom C-Mount tail with M4/3-Mount front adaptor could be made. Otherwise it would come down to a custom rear tail for the 0.71x speedbooster. This is doable but introduces other difficulties including some very fine internal 0.5mm thread cutting.
  9. I had a look for myself. The CPs seem to have disappeared. There were quite a few on eBay a few years ago. They were available in CP-Mount and ARRI Standard/B-Mount when I collected mine. I obtained PL-Mounts from Ken Hale at Whitehouse AV. The available lenses may have been scooped up after CP-Mount to M/3-Mount adaptors became available. They were handier in some ways than the Optars because they have 52mm filter mounts in the fronts like stills Nikons and can accept close-up dioptres or in my instance a cinemascope adaptor which was not an outstanding success.
  10. The Elites and Illuminas apparently share a common optical ancestry, Lomo I believe but I could be wrong. They are T1.3 lenses. They behave similarly in use with an apparent sweet spot of T2 to T2.8. The test was shot with IR and ND filters so the lenses could be set to T4. In the last T-stop to wide-open, the lenses flare. For what it may be worth, here is a clip of a test with a mixture of Elites and Illuminas on a SI2K although the clip title does not mention Elites. The Illumina set consisted of 8mm, 9mm, 12mm, 16mm, 25mm, 50mm. The Elites in the mix were 35mm Series 3 which is physically comparable to the Illuminas and 85mm Series 4 which has a more modern body. CP Ultra T* lenses which are T1.3 lenses, 9mm, 12.5mm, 16mm, 25mm perform well and have slightly more apparent sharpness at the wide apertures. The 12mm specimen I have is excellent. Except for the 9mm, they are Super16mm capable. The 9mm can be modified but goes rather soggy at the corners when wide-open. Depending upon their age, condition and how recently serviced, the image from the CP Ultras may walk in a circular motion during focus pulls, most noticeably on the longer lenses. These lenses were made for Cinema Products by Kowa in Japan. Note that the circular flare in some of the images was due to a mattebox donut falling out and causing internal reflection and is not a lens artifact.
  11. 44mm is also the Flange to focal distance for Canon EF-Mount Lenses.
  12. Are you aftering a moonlit scene or a shot of the moon itself in background of a composed and artificially lit scene? If you could describe your actual intended shots this might be more helpful. If you put an 85B daylight correction filter on your camera, you will lose 2/3rds or more of a stop. This muchly defeats the choice of using tungsten-balanced film which was originally purposed towards gaining the most faithful colour rendition out of the once common tungsten lamps which are limited by available power sources. Daylight has plenty of power to spare when correction filters are used. Filters will require you to light your subjects more strongly and if your lighting is to be LED or HMI which is nearer to daylight colour temperature, then the decision for tungsten balanced film might need to be re-examined. You might be able to take a bet each way and use a 81EF filter which may leave you with a little blueness in the colour but leave you with a bit more wriggle room for colour grading. You will still lose about 2/3rds of a stop. It confers a sweet effect in very early twilight with the sunset sky in background. What speed (ASA or ISO) is your tungsten balanced film? I doubt that moonlight alone will give you much of an image of anything except the moon itself or light clouds across or around it either as a shot or in background of a scene. The moon itself can be quite bright. If you want detail of the moon's surface, then you will need to set the lens aperture to suit. David Mullen can advise better than I can about exposure for the moon. Is something like this what you are seeking to film? Here is a link to another discussion which may assist you. https://www.rogerdeakins.com/camera/working-with-filters/
  13. My personal preference would be to avoid the 100ft reels. They will scratch your film as there are no raised edges at the hub centre to support the image area away from abrasion. As a workaround, you could cut 3mm broad strips of gaffer tape and make ridges inside around the reel hub but the chances of making an even surface and not getting sticky cack on the image frame are pretty low. Unless you can afford to waste the work involved in shooting, you might be better off rescheduling your shoot to give yourself time to aquire the correct rollers.
  14. The Pan Cinor Som Berthiot 17-85mm lever action zoom lens and Angenieux 12-120mm zoom lens were made with prism split viewfinders integrated in the lens itself. The Som Berthiot has a C-Mount. The Angenieux for early CP16s had a clasp and ring arrangement for easy removal of the lens. The clasp and threaded ring assembly was itself attached to the camera by a C-Mount hollow ring nut. There was also a wide-angle zoom by Angenieux with the same arrangement as the 12-120mm. The Som Berthiot is usable with a non-reflex Bolex but holding that heavy side-viewfinder steady may be too much for the friction of a C-Mount thread when fitting it up to a Bolex. As for the Angenieux lenses with side viewfinders, I suspect that the diameter of the clasp and ring may be too wide for the 3-lens turret of a Bolex and interfere against the centre pivot but am not sure as I have never offered one up to a Bolex. If the lens does not come with the receiver which attaches to the camera along with its hollow C-Mount ring nut, then the lens is of no use unless one can re-make a receiver which is not easy.
  15. Further to the previous reply, the accompanying image illustrates where a clearance for the fillet radius should exist. If you are wondering what that object is propping up the PL-Mount, it is a plastic template of an adaptor for the Century Optics 16:9 anamorphic adaptor for Sony DSR PD150 camera to fit to a lens filter diameter of 52mm with 0.75mm pitch thread. I made made one in metal to fit Nikon AIS lenses and CP Ultra T* 16mm cinecamera prime lenses.
  16. Sometimes with PL-Mount adaptors, there is a sharp edge instead of a rounded edge or chamfered edge on the inner front diameter of the hole which accommodates the lens shoulder. This butts against a fillet radius in the front corner of the shoulder of the PL lens tail and the flange face. It holds the lens away from the flange face ever so slightly and sometimes makes the lugs on the mounting ring catch or barely overlap before snugging down. More likely you will need to shim your mount but the interference by the adaptor with the fillet radius would be the first thing I examine.
  17. Some years back, I tested a 16mm cinema camera lens set on the SI2K with a focus card (Siemens Star) with lighting adjusted with each aperture change and the card carefully framed. The sharpness numbers given by the SI2K are most consistent when the wider focus "window" is selected. The sweet spots I found for a set of CP Ultra T* lenses were 9mm T1.35 = T3, 12.5mm T1.25 = T3.8, 16mm T1.25 = T3.5, 25mm T1.25 = T4. The best of the cine lenses gave a 112 sharpness number. To the Super16mm sensor, the best of the Nikon AIS f1.4 stills lenses yielded a 65 sharpness number. The sweet spot tended to be in the zone f4-f5.6. The best of two old Cooke (Taylor, Taylor, Hobson) Speed Panchro Ser 2 cine lenses which had been distressed by fungus and inexpertly cleaned, surprisingly slightly bettered the best of the Nikons and was best at f5.6. There is a far more scientific way of testing to don't pay too much heed of my observations.
  18. Keep up the good work. I come back from time to time to catch up on the news.
  19. The Chinese optical manufacturer Venus Optics, branding as Laowa, has released a 1:33 rear anamorphic adaptor which attaches to a PL-Mount camera and accepts PL-Mount lenses. Super16mm lenses penetrate too far behind the flange face and will clash against the front optical element of the adaptor. Not all 35mm format lenses will fit either. It captures a narrower field-of-view than a spherical lens attached to it but yields a cleaner image than many front anamoprhic adaptors. You will not achieve the vertical and horizontally stretched bokeh effect unless you significantly detune the adaptor's relay focus adjustment which then softens the image including the in-focus subject. In a weird sort of a way, you can use the Laowa adaptor on the rear of a lens and a 1:33 front anamorphic adaptor on the front of a lens as a combination to achieve a 2X + squished image. I am not sure what utility there is in doing this but it can be done.
  20. Very slightly divergent in this topic, this article, if you have the patience to read, features the Asian production entity, Shaw Brothers of Hong Kong and Singapore. Their anamorphic films were heralded with the full screen logo "Shawscope". As a teenager, on seeing the logo, my first cyniical thought was that it was asian copycatting and branding of someone else's proprietary hardware. However, on reading this articale I have been re-educated. According to the article, their Japanese Toho lenses were derived from Kowa and Dyaliscope designs. Some of the lenses featured a rear anamorphic optic, a product which Chinese optical manufacturer, Laowa has recently introduced in its line-up. https://www.davidbordwell.net/essays/shaw.php
  21. For John Obrien, some supplemental info regarding Nikon lenses and a front anamorphic adaptor. Recently I remade the barrel of a Laowa rear anamorphic adaptor to accept Nikon F-Mount stills lenses which I have been using via a EF-Mount adaptor ring. Whilst I had the lathe set up for fabricating a tractor part and a suitable short piece of metal stock was available, I decided to remake an adaptor for an old Century Optics 16:9 anamorphic lens which was part of a Sony PD150 kit.I had roughed up an adaptor from pieces of PVC water pipe fittings years ago. It was never much good and I had intended to remake the part in metal once I had established the form which worked. I never got around to it and made do with the plastic piece for the few times I wanted to use the adaptor. When in use I was hoping and praying the blue plumber's glue would not let go.Cutting fine 0.7mm pitch filter threads is a bit of a nightmare with my meagre skillset and the cheap chinese lathe. It can be done but lots of workarounds are needed to get the precision. The thread cutting is the very last operation. It is the most likely to go wrong and ruin all the work which came beforehand, like about five hour's worth.The Century Optics anamorphic for the Sony PD150 has an exit pupil which is smaller than the Letus, rare Panasonic, rarer Optex and the newer SLR Magic anamorphic adaptors people use. The fitment to the PD150 was via a bayonet attachment which held the removable lens hood.Rather than cut out the reliefs for the bayonet lugs in the new adaptor, it is easier to slack off the stop screw in the attachment ring, take it all the way off, offer into the rear of the anamorphic lens the flange of the new adaptor then screw the ring back on behind it and cinch it firm.If it was to be used often and rapid lens changes were desirable, then several adaptors could be made complete with the bayonet reliefs and remain attached to lenses. As it will be infrequently used for script teasers, I won't be making more. The Century anamorphic lens has an adjustment so where the adaptor ends up when screwed into different lenses does not matter.For professional cinema lenses it is not an option. For smaller stills lenses like the Nikon F-Mount lenses with 52mm filter fronts and small diameter front elements, it works fine. The sharpness and clarity are adequate but I would not say outstanding. The anamorphic lens was originally purposed for standard definition television quality.The F-Mount lenses known to work with it with the URSA Mini 4.6K EF are the Sigma 28mm f1.8 (requires step-up ring), genuine Nikon 35mm f1.4, genuine Nikon 50mm f1.4, genuine older and newer Nikon 85mm f1.8. The front anamorphic increases the field-of-view the sensor sees through the lenses and you get a few flares and ricegrain bokeh on pinpoint highlights.The adaptor is the skinny gold-coloured piece of bronze between the anamorphic lens and the Nikon lens.
  22. Dom Jaeger. A very valid point. My hack for Nikons which was a personal project is highly unlikely to ever see a genuine production. The existing Laowa PL - PL adaptor is viable for the company's own zoom lens, some other zoom lenses, prime lenses and wide-angle lenses that an industry standard front adaptor would not suit. Interestingly, Laowa cine standard anamorphic lenses are to be marketed in the near future.
  23. Sintered bronze bearings were also known as "Oilite" bearings. My understanding was a special oil was required and the wrong oil would clog the microspaces and the bearing would wear. I too have not been able to find any particular info but it has been awhile since I searched. Makes and maintainers of analogue aircraft instruments might have a clue. There may be some light fractions in the correct oil which gas off over time as the recommended service interval for the CP was six months, whether used or not.
  24. For curiosity. A test drive of the modified Laowa 1:33 rear anamorphic adaptor with a Laowa 12 lens for Nikon F-Mount attached. Camera is an original "big" URSA 4K PL recording in Pro-Res LT. The sport is Australian Rules football at local competition level.
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