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Found 4 results

  1. I've been deep diving into the world of DIY Anamorphic lenses and now I can share some of my experiences. Recently, I modified an old anamorphic projection lens so I could use it on set. My website has a full version of this post as well as a PDF, but I wanted to share it here in its entirety for discussion. WEBSITE LINK The Bell & Howell Anamorphic Lens (BH16-2) is an old projection lens originally meant for projecting and de-squeezing 16mm film. Cinematographers can easily modify and adapt this lens for practical use on set with minimal additional parts. The following guide gives close to a step-by-step tutorial on how to modify the BH16-2 for practical use in cinematography and photography. However, there are some steps that won’t be explained, such as how to grease a helicoid, use a spanner wrench, or align an anamorphic lens. Acknowledgements Tito Ferradens for his saint like work on DIY Anamorphic Chris Bold for paving the way of trial and error Richard Gale for shining a light when we needed it Key Concepts Before beginning the modification, the BH16-2 has a key concept about its original design. A built in variable diopter makes the BH16-2 an easy and affordable lens to modify in comparison to other projection lenses. Variable diopters are a clever and simple way to circumvent the double focus anamorphic lenses require. An anamorphic lens contains an anamorphoser and a spherical lens. The anamorphoser compresses/squeezes the image horizontally; additionally, it controls the horizontal focus of the image. The spherical lens controls the vertical focus of the image and aperture (not present on fully built projection lenses). These two lenses are focused at the same time mechanically in high end anamorphic lenses, called single focus. When building a DIY anamorphic lens, cinematographers typically use the anamorphoser from a fully built anamorphic projection lens and clamp it together with a different spherical lens. Both the anamorphoser and spherical lens, however, will need to be focused at the same time, called double focus. These fully built DIY anamorphic lenses lack any mechanics for controlling both focuses at the same time, so cinematographers have to manually pull focus on both parts by hand. Variable diopters, on the other hand, take advantage of optics to control the focus of the two parts. In photography/cinematography, diopters are filters that decrease the maximum focus distance of the lens, allowing the user to focus closer than the lens originally can. Diopters are often used in macro photography, but have a prominent application in anamorphic cinematography. A diopter can have a positive or negative optical power. When diopters of different powers are combined together, they can increase or decrease in power. A variable diopter uses a combination of two diopters that, when close together, equal a small power, but grow in power as they seperate. The larger the power of the diopter, the closer the maximum focus. Setting both the anamorphoser and spherical lens to infinity guarantees they are focused to the same point. Then, attaching and using a variable diopter can move that infinity point while keeping both lenses focused on the same point. A variable diopter makes the fully built anamorphic lens a single focus lens. This is what the three main parts of the DIY anamorphic lens looks like: All three of these items are clamped/built together to create a DIY anamorphic lens. The original BH16-2 is exactly like this, a variable diopter built onto the anamorphoser that is screwed onto the spherical lens: The downside of the original anamorphic lens is that the variable diopter requires numerous full rotations to pull focus from infinity to a close focus. Most lenses for cinematography rarely reach a full rotation from infinity to close focus. Additionally, the original spherical lens has no aperture and is near impossible to mount to any camera. This modification fixes the over rotation, corrects infinity, gives a better close focus, and allows for attaching various different spherical lenses. How to Modify the BH16-2 From left to right are the three main parts of the original BH16-2: Spherical Lens, Series 7 Adapter Ring, and the anamorphoser with built in variable diopter. For this mod, we will: Replace the spherical lens with one of our own Convert the adapter ring to our new spherical lens Replace the variable diopter helicoid with a new helicoid Parts & Tools You will need the following parts: BH16-2 with original Adapter Ring Nikkor 85mm AIS F2 Lens 58mm to Series 7 Step Up Ring 58mm Circular Polarizer Rubber Gasket about 54mm big with an interior diameter slightly smaller than 45.95mm These are approximations. When in doubt, use bring the removed variable and helicoid with you to find the right size gasket. [Alternative to Rubber Gasket] 3D Printed Diopter Holder 58mm to 58mm Helicoid Focusing Ring 17-31mm Vid Atlantic Lens Clamp, 77mm Appropriate step-up/down rings from 77mm to the 58mm Helicoid Focusing Ring 1/4 inch 20 lens support point from a Rapido FMJ Appropriate bolt size to mount this support to the Vid Atlantic Lens Clamp PVC Tape You will need the following tools: Flat Head Screwdriver Lens Spanner Wrench Rubber Gloves Cotton or cotton like gloves Hex Keys Knife or Dremel Tool 1 - Replace the Spherical Lens This is the easiest step. The original spherical lens has no aperture control, projects a small image circle, and is near impossible to mount to a camera. Instead, we’ll use a photography lens that can do everything the original spherical lens can not . For this project, we’ll use the vintage Nikkor 85mm AIS F2: The Nikkor 85mm AIS F2 is a reasonably priced lens that delivers sharp, neutral looking pictures. It doesn’t have the clinical feel of modern lenses, but still maintains the sharpness for even the largest of screens. Of course, you’re not limited to this focal length, maximum aperture, or lens. The BH16-2 is a narrow lens to begin with, so anything wider than an 85mm vignettes on a S35 sensor. However, tighter lenses like a 105mm or 135mm work well with this anamorphoser. 2 - Convert the Adapter Ring The adapter ring that comes with the original lens has a specific thread on the inside that screws to the anamorphoser. The thread on the rear of the anamorphoser isn’t an industry standard thread and requires the original adapter ring if a cinematographer wishes to use step-up rings to attach the new spherical lens. If you do not have the adapter ring, then you’ll have to use another lens clamp to attach the spherical lens to the anamorphoser. This guide will focus on using the original adapter ring. The rear exterior threading of the adapter ring is Series 7. In the above photo, a 58mm to Series 7 Step-Up Ring is screwed snugly onto the adapter ring. Additionally, the adapter ring is then screwed back onto the anamorphoser. In Section 3 of this guide, the anamorphoser will be modified to stay locked in alignment via 15mm rod support. Currently, the adapter ring with the step-up ring attached will make it impossible to correctly mount the spherical lens to the camera because there is no ability for the lens to rotate. To fix this issue, a modified circular polarizer (CPL) will be attached. Using a spanner wrench, remove the polarizer glass from the CPL. Screw this empty CPL to the modified adapter ring. Now you can mount the spherical lens to the anamorphoser and still rotate the spherical lens into the camera mount. 3 - Replace Variable Diopter Helicoid The next, and most complicated step is to replace the variable diopter helicoid (VDH). Two flat head screws prevent the original VDH from being completely screwed off. Remove these two screws: Once the screws are removed, twist off the original VDH completely: The original VDH only contains one of the diopter elements, the other is built onto the anamorphoser. Our mod will remove the diopter in the original VDH and place it into the new VDH. Using a spanner wrench, unscrew the ring that holds the diopter in the original VDH. This ring will be tough to unscrew and will require considerable amount of force. It’s best to lock the spanner wrench and use rubber gloves to grip the VDH. Other cinematographers have tried lightly tapping the exterior of the VDH to help loosen the ring. There is no glue in the rings of the VDH. Once the ring is removed, push out the diopter with your finger. (It’s recommended to use cotton or cotton like gloves to avoid smudges and scratches) Above are the three removed items: the original helicoid, the ring that held the diopter, and the diopter itself. Next, we will place the diopter into the new helicoid. The helicoid that works best with the BH16-2 is an M58 to M58 Focusing Helicoid Ring 17-31mm. This specific size perfectly fits over the anamorphoser. Most of these new helicoids are too stiff from the factory. The best practice is to re-grease the helicoid before installing the diopter. Next, the diopter will be inserted into the helicoid. A rubber gasket will hold the diopter in place within the helicoid. [Alternatively, a 3D Printed Diopter Holder can be used] This particular rubber gasket has an interior diameter that is too small, so a knife or Dremel tool was used to widen the diameter. The diameter should just smaller than the diopter itself because the rubber will stretch around it and hold the diopter snugly in place. Before installing the diopter in the gasket, install the gasket into the helicoid by pushing it in: Once the gasket is pushed into place, push the diopter into place: Above are the front and back of the new VDH with the diopter held by the rubber gasket. Next is installing the new VDH securely to the anamorphoser. The sturdiest solution is to use a clamp like one of the Vid Atlantic anamorphic clamps. The particular clamp used in this guide has a front 82mm thread and a rear 77mm thread. Once the lens is complete, it will be too heavy for the camera mount and adapter ring. The clamp will also become the lens support point. The female 1/4 20 support point from a Rapido FMJ was used for this clamp mod. Additionally, step up rings were attached to the front 82mm thread. Once the step up rings are attached, the new VDH is screwed into place on the lamps clamp. Finally, the new VDH will be clamped to the anamorphoser. Before attaching the new VDH, use PVC Tape to cover the anamorphoser. The tape only needs to cover where the bolts of the clamp will touch. Doing this protects the anamorphoser and gives extra grip for the bolts of the clamp. Once taped, attach the VDH! Screw the anamorphoser + new VDH to the spherical lens. The newly modified lens is nearly complete, but the anamorphoser needs to be aligned. Attach the lens to a camera, then attach the rod support, and finally align the anamorphoser by loosening the VDH clamp and rotating the anamorphoser until alignment is correct. Once it is, lock everything down. It’s important to use rod support with the mod because the various step-up rings and the spherical lens are too weak to hold the weight of the anamorphoser and variable diopter. It also locks the alignment of the anamorphoser and spherical lens. The added stability of the lens support is a requirement for the BH16-2 to be practically used on set. The final step is to set the spherical lens to infinity and the lens is ready to shoot! A Few Notes Infinity on the spherical lens largely depends on how accurate the focal flange distance is of the camera mount. In most cases, the infinity markings on the spherical lens won’t be the infinity you set the lens to. The best way is to mess with the focus of the spherical lens and variable diopter until they line up. Once they do, you’ll only need to pull focus with the variable diopter. The anamorphoser is already set to infinity. However, these lenses are old and it may have been dislodged over time. This guide doesn’t address how to fix the anamorphoser and it is recommended to seek professional services for the anamorphoser. The diopter element within the rubber gasket will need some adjustments. Collimation is the accurate alignment of optical elements and the diopter will most likely be aligned incorrectly once it is installed. The easiest solution is to adjust the diopter element within the rubber gasket until sharpness is even across the image. Additional Resources Rich Bold’s Journey - https://www.eoshd.com/comments/topic/8996-seeking-info-about-the-bh-projection-lens/ QuickHitRecord’s Journey - https://www.eoshd.com/comments/topic/6411-bell-howell-16mm-anamorphic-lens/ Tito Ferradans - https://www.tferradans.com/ Anamorphoser measurements by Rich Bold:
  2. Hello folks, I'm new on cinematography.com, i'm getting into super-8 as a member of an analog associative Photo/Cinema called ZebraLab based in Geneva : https://zebralab.info/. I am also a photographer by job. With the guys from the lab, we are/have built two machines to cut reels of Fomapan R100 DS8x30,5M to 4x S8x15M to be loaded in Lomo Reloadable Cartridge. That make it really affordable as we buy from Foma factory shop, we are around 7€ for the film and around 3€/film for processing (detail below). According to Super8Wiki, Lomo Reloadable Cartridge acts as 64T/40D -> http://super8wiki.com/index.php/Super_8_Cartridge_Notch_Ruler (down of the page). We would like to turn them into ASA 100, but we don't know wich notch ruler we should trust : - The one from Super8Wiki : super8wiki.com/images/6/6f/Cartridgenotchruler.pdf - Or that one who says the Super8Wiki notch ruler is not that good : http://www.peaceman.de/schmalfilm/super8/S8_Notch_Tools_v1.0.pdf We asume that : as the Fomapan R100 is black and white and that the contrast change induced by the CCA filter is not that big of a deal for us whe should turn the ASA 40D to an ASA 100T, thus cuting a filter notch down on the cartridge and enlarging the upper notch, correct ? Also, as several of us own (and ZebraLab also) a Canon 814 XL-S in working condition, we would like to give a shot at turning one of the cartridge to ASA 400, as the film stock can be pushed 2 stop during processing : we are processing black and white reversal with a mix of two method : Potassium Permanganate + Sulfuric Acid bleach and using a photopaper developper, as the emultion if soften by the bleach, we do hardening bath before to the bleach and one hardening fix bath after second developpement. The hardening concentrate is the Tetenal one (Aluminium Sulfite + Acetic Acid but that need confirmation). You can watch the result here on a Kodak Tri-X 200. (i found the result to be a bit too much contrasted...) But, according to the Super8Wiki notch ruler we are not sure that the Canon 814 XL-S can read ASA 400, even if it say so on different website (that would mean not a notch is pushed by the cartridge, 6 notches without the filter notch, and we tried cuting into an old K40 to make it ac as a ASA 400T but it doesn't seem to make a difference for the exposure sensor, that same camera read and exposed correctly the Kodak Tri-X 200 that you can watch on vimeo...). So : is it possible to turn a cartridge to ASA 400T (or around like a 500T), and would a Canon 814XL-S be able to read it, it can read Vision3 500T, so i guess yes, but how ? That's it for the moment, if you have solutions and/or questions, i'm up for it ! Bye, Jeremy
  3. Hello all, this is my first post upon joining these forums. So basically I'm a bit of a DIY tinkerer whose interests in video film have skyrocketed (after buying and selling a couple I've settle on a Beaulieu 4008 TM II Super 8 and a Krasnogorsk K3 Super 16mm. However, I've recognized a new format for Super 8 called Max 8 (basically widescreen variant of Super * which is normally 1.33 near square format) and the beaulieu is a great camera for this, despite some modification must be done. I am aware that the company Pro8mm does conversions like that, but looking at the price tag I think to myself "well what can they do that I can't?" And from what I've collected the whole process goes as such more or less: removal of the 85 filter system (which I have done myself), widening of the film gate, adding template marks to the viewfinder to mark the resolution, and to recenter the lens and viewfinder to the new window. My Krasnogorsk is almost a template of what to do give or take, with most of the modifications occurring with the widened gate and re centered lens ring and viewfinder. What do you guys think; any advice?
  4. Hello all, I was recently lucky enough to acquire a Canon 1014xl-s from my father-in-law (he'd had it since 1981 and only used it once!) and have shot a couple of cartridges on it, which came out great. I'm a bit of a tinkerer though and on having such a good experience with the Canon I decided I'd like a less valuable model that I can afford to be a little more aggressively investigative with. In light of this, last week I bought a Nikon 8x Super Zoom. As I got the Nikon very cheap, I've decided I might like to do the shutterless modification on it that is described on the Super 8 wiki. I'm hoping this will give me a more tactile appreciation for the internal workings of a Super 8 camera, add an interesting feature I can experiment with, and generally satisfy my occasionally calamitous interest in taking things apart and (90% of the time) putting them back together again. In respect to this, I was wondering if anyone who has done the mod would be willing to temporally reverse engineer it, post pictures and also a fuller description (a lot to ask, I know). What confuses me in particular about the wiki description is that it seems to split the operation in two (the repair section also mentions shutter removal), which has left me unsure if both are necessary or if using either one has the same effect. In addition, the line “access the main drive gear, and "brake" it with your finger as you shoot>> 8,7,6,5,4,3,2,1,0fps” is not entirely clear to me. The combination of the word "finger" with "drive gear" fills my mind with images of gushing blood. Any elaboration on that would be appreciated. Thank you for any insight you might be able to provide. This forum has proved an invaluable source of information during these initial fumblings I’m making into the Super 8 format. Wiki entry: http://super8wiki.com/index.php/Nikon:_8x_Super_Zoom:_Disassembly
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