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Ruben Arce

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Ruben Arce last won the day on May 23 2016

Ruben Arce had the most liked content!

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About Ruben Arce

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  • Birthday 09/15/1981

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  • Occupation
    Cinematographer
  • Location
    Salt Lake City
  • My Gear
    Ursa Mini 4.6k, Sony FS-700, Eclair NPR, CP-16R, Scoopic MS, Nikon R10, Nikon D810
  • Specialties
    Director of photography, Camera operator, photographer and editor.

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  1. I don't know if you tried using other manual lenses with the pocket and an external light meter before with different results, but in my experience the BM cameras are the ones who are not rated properly, I mean pretty much all manufacturers "lie" when it comes to ISO on their cameras. I have a BM Ursa Mini 4.6k and since I like using my external light meter I shot some tests to determine where middle gray was, long story short I determined that I had to use ISO 250 on my light meter when the camera is set to ISO 800 to get what I consider proper exposure. Manufacturers, specially at the time when those cameras came out were trying to under expose images to protect the highlights and sell the idea of a wider dynamic range. If you read the manual you will find a scale where they place "middle gray" at 38 IRE not at 50 IRE which is in the middle. I have a Sony camera from the same time period and with S-Log2 they were placing middle gray at 27 IRE, that sells the idea of higher ISOs on their cameras and help them to protect the highlights avoiding blown up highlights and making their cameras look "better". Most people don't use the middle gray method, they use false color, zebra, wave form scopes and that kind of stuff, most people don't use an external light meter these days and RAW and LOG formats allow them to say their cameras are rated at ISO standards, but it's tricky. The Meteor lens is not rated on T-Stops as you mentioned before, so add another factor there, I would say one third less of light maybe.
  2. I did the same thing a few years ago. I had some bulk Ilford HP4 and I wanted to test my Konvas 2M. I did loaded some film on a core, loaded the camera, shoot with it and everything was just fine. I just wanted to test the camera so I was more than happy with the results. I didn't shoot much, but I didn't get weird reflections coming back from the pressure plate or anything, just some nice sharp images.
  3. I read your post since the first day you posted it, I have been working on modifying camera mounts and the K3 is one of my prospects. I shot several times using M42 lenses with the K3, actually I used to have a set of lenses for the camera that now my friend in LA owns, it is perfectly possible as everybody told you here, but I didn't know if I wanted to try to say something when you are so reluctant to hear what people have to say, specially when every thing people told you here is right. You are kind of right on the info that you have about FFD but those people actually have it right. It's not that complicated really, and as you pointed the information is online, but if you don't want to accept that info I don't know what you can do. I shot 4 times using the K3 with my set of lenses: Zenitar 16mm f2.8, Vivitar 28mm f2.8, Super Takumar 50mm f1.4, I can't remember the brands on the other ones, but I had an 85mm f2.8, a 135mm f2.8 and a 200mm f4, so here is a setup from someone who had actually shot with a K3 and M42 lenses and here are a couple of HD samples of films shot with the K3, the first one is when the camera was regular 16 (cropped) and the second one converted to Super 16. All the lenses used on this two tests are m42 lenses desiged for still photography. https://youtu.be/StGgzgXf-rg https://youtu.be/bNXQs4DBOv0 Do I have experience with the K3? Well I converted the camera that I used to shot those films to S16 myself, I lubricated it and replaced the light seals, I bought the re-centering ring and I tried to adjust it to get it close the the appropriate FFD and I shot 4 rolls with the camera that are sharp and that let you see what the camera and the lenses can do. Every M42 lens that I had was different, they looked different and I wanted to move on to better cameras and lenses so I sold that one and the lenses. I recently got another K3 that I'm going to use to experiment with mounting lenses. The information that other fellow members presented was correct. The FFD of the M42 mount is 45.46mm and it is the same on 35mm still photography cameras and on the K3. Getting a camera serviced is extremely important, because a technician will adjust the FFD, and the focusing screen distance. You have been talking about the FFD as if it were the only important part of the camera and it is not. You may have a FFD perfectly measured and if your focusing screen is not at the right distance you are going to see images out of focus on the viewfinder. You can have a perfectly set FFD and focusing screen distance and if you don't know how to adjust the diopter you may get out of focus images. Now you think FFD is critical and it is, but the camera will still work if the FFD is not right on the spot. I did modify the mount on my K3 with sand paper and I never had the FFD adjusted and I did get sharp images every time, the difference is if the FFD is not set correclty you cannot trust the measuring distance (witness marks) on the lens so you cannot grab a measure tape measure at 10ft and then set the lens at the 10ft position and expect it to be right and your lens may not focus at infinity depending on where the actual distance is set. Focal Flange Distance is important, yes, because if it is properly set you can trust your camera and lens even when your eye is telling you something different and you can get images in focus even without a viewfinder. If your friend didn't get images in focus it may be because the focusing screen was not at the right distance, or because the diopter was not set correctly. I really recommend "The 16mm Camera Book" (Underdahl) you can learn a lot from that book and you can learn how a camera is actually tested. The best way to know if a camera is right on the spot even after being serviced (to make sure) is to shoot film. I do test my cameras at home shooting B&W film that I process and scan here. If FFD is correct, if the focusing screen is at the right distance and if the diopter is set using measurements and not your eye, you should have sharp images every time, and you should be able to tell by looking at the viewfinder. I'm not sure I want to have a discussion or conversation with you about this. I hope you get some useful information, you can see some samples, so you can see it's possible. I'm sure other members have footage but they didn't want to deal with your attitude. People here are very nice and very, very helpful please don't disrespect them.
  4. I don't think your footage looks terribly bad. 16mm film is going to look soft if you compare it to digital specially footage from DSLRs with big sensors to begin with. When it comes to exposure I have seen a lot of people assuming that they have a perfectly serviced camera running at 24fps and a 180° shutter. Tyler already mention this, but I'll put it in a different way... If you are using a Bolex that hasn't been serviced you don't know if it's running at 24fps for real (Not a crystal sync camera anyways) so you may be losing or adding some light there. You have to find what the shutter angle on your camera is. Shutter angle is different from one model to another. When it comes to Bolex cameras you are going to find numbers like 133, 144, 165, 170 & 190 degrees depending on the model, assuming you have a regular H16 Reflex bolexcolector.com states the camera has an actual shutter angle of 144° (1/60th) Now some people will tell you to meter at (1/80th) to compensate for the light lost on the prism. If you are assuming the camera has a 180° shutter (1/44th) you are losing a third of a stop there, if you are not compensating for the light that is lost on the prism, you are losing another third of stop there, so far you are underexposing by two thirds of a stop. Now let's say you are using lenses that are marked in F-Stops instead of T-Stops and you are not compensating for that (you typically lose another third there) you could be underexposing by a full stop at that point. Shutter angles vary from one camera to another, the K3 has a 150°some S8 cameras have shutter angles of 220° Profesional cameras 180° for example. After considering all those factors I give film a 1/2 of a stop of compensation (overexposure) to keep grain low and to keep some info in the shadows. Soft Image... You don't mention how you are judging focus. You may be adjusting the diopter to your eye and then focusing by eye, that's what you are supposed to do right? Well it's not a digital camera... What you see may not be exactly the same thing the camera is capturing, the Focal Flange Distance is very important and it it' not perfectly aligned you are going to get soft images, specially with wide angle lenses and small f stops. If you are sure the mount of the camera (FFD) is right on the spot then you can use a measure tape to set focus on a chart and then adjust the diopter to your eye. You can do this shoot some b&w film, process it at home and see the results. Some people will tell you to adjust the diopter at a point where you can see the "grain" on the focusing screen, but if the focusing screen is not at the right distance you are going to get soft images. I mentioned wide angle lenses are more prone to show this problems, since this lenses project a very shallow back focus image. The viewfinder on the regular H16 is very dark, and focusing a wide angle lens on a 16mm camera is not an easy thing even with better viewing systems. You may try putting a lot light on your subject for a moment just to make sure it really is in focus, but again if you are not sure the camera is right on the spot it's going to be complicated. Are you using adapters? There are a lot of factors that you have to consider when shooting film.
  5. I agree the cost of shooting film is kind of expensive, specially if we compare it to the no cost at all of shooting with your phone or a digital camera, but if you miss shooting on film, enjoy the process and have fun you could shoot Ektachrome 100 on a Super 8 camera, get it processed and project it at home. (still kind of expensive) You don't have to get the film scanned every time and certainly not at the highest resolution.
  6. Well if your camera was converted to S16 I think it's a good idea to use other lenses, so you can take advantage of the S16 area, but don't forget that you get a 3X crop factor with S16, so a 135mm is going to have a field of view of 405mm for example, if that's what you need great, and you can get some 8mm lenses with Nikon mount now, so I think it's a good idea. Focal Depth or focal flange distance is both easy and complex. It's easy because as long as you have a lens set to the proper distance (46.5mm for Nikon) the lens is going to work as intended. The difficult part is to get it there. I'm not a camera technician by the way, but I understand how those things work. So basically your technician has to adjust the lens so it is centered and then with proper tools set the focal flange distance properly, by measuring obviously and then when it's close to proper distance they use shims to extend the distance or they have to machine the part to reduce the distance depending on the case, so easy to understand it, not so easy to do it. A camera technician should be able to do it, specially one who can modify or make parts using a lathe or a CNC machine. I got a K3 with the only intention of converting it and modify it in several ways. I have some manual Canon lenses so in my case I want to go that way. I'm going to design mount and 3d print a prototype and if everything works fine I'll have it machined. I'll let you know how it goes.
  7. Nikon lenses are good. The lens that comes with the camera is not bad, it's actually kind of good, the thing is if you want to convert the camera to S16 the Meteor (kit lens) is not going to cover the S16 area below the 27mm position. Technically it is possible to convert the camera to Nikon mount since the focal flange distance of the Nikons is longer than the M42 one. I just got a K3 in like new condition, and I'm going to convert it to S16 and I'm going to try to give it a Canon EF mount. You can always use M42 lenses too, but to be honest if your camera is not S16 and if you don't need wider or longer lenses, I think the Meteor works just fine or better than other ones. Lenses designed to cover the 35mm full frame can cause internal reflections. I used M42 lenses with another camera and I didn't see any problems really, but you are adding another factor of risk.
  8. The system that moves the loop formers out of place is made out of threads, which in the best case scenario is at least 30 years old. If the system doesn't have enough tension the loop formers don't move far enough causing scratches and in "registration" issues. I would definitely remove the loop formers. I just got a K3 to play with and that's one of the first things I'm going to do with it.
  9. No problem Jack, Yeah cleaning everything will definitely help, specially the gate and the pressure plate. try cleaning the rollers with alcohol sprocket, by sprocket if you can't polish them. Removing the loop formers will make the camera "manual" to load. Is not difficult at all, just watch some videos on youtube, try loading the camera a few times with dummy film and run it trough it and you will get used to it. I used to do it in total darkness and a lot of people have done it too. A good trick to make sure the sprocket holes are properly engaged is to move the film with your fingers back and forth when the film is engaged in the rollers (sprocket) and make sure it is engaged on the puller when it goes trough the gate and pressure plate. That guarantees the film will stay in the same shape and loops are not going to change in size.
  10. I used to have a K3 that I converted to S16 myself, so I'm familiar with the camera. First of you have to clean as much as you can inside the film compartment. If you see dust I would start cleaning with a toothbrush, (carefully) then compressed air is a good idea. The stuff that you are seeing on top and bottom of the image is dirt accumulated on the pressure gate. If you are not familiar with removing the pressure plate, watch some videos on you tube to see how to remove the pressure plate and then clean the gate and the area. That stuff is massive and looks like emulsion accumulated on the gate after some time without a good clean. You can remove that stuff with a wooden or even plastic tooth picker. Never use anything made out of metal to clean the gate or any other parts of the camera really. You can use alcohol to clean the gate, the pressure plate and the rollers that touch the film. I can tell the camera was converted to S16. The scratches that you are seeing are on the area that was not designed to be used with film, so you will have to clean those areas that I mentioned before and ideally polish those pieces. If you camera has the loop formers that's another thing that you should remove. They are famous for scratching film. I don't think that's the case here but that's a good idea anyways. I had the same problem with my camera and as soon as I polished those parts the scratches were gone. I used a $10 dremel tool and polishing compound to do the job. Be careful with plastic parts, a rotating tool would damage those, so don't use it on plastic parts. I know this is not the ideal method, but if you don't want to spend the money getting the camera serviced that's a good work around.
  11. I did it before and never had any problems, I guess I need a new soldering pencil too. I just got another set of batteries, I was almost done with the project and my design looks great and I'm sure it will perform well. Technically I broke the seal the manufacturer had on the batteries so I lost the warranty. I saw some spot soldering machines for around $100 usd which is not bad at all, but they are heavy and bulky, so another set of batteries for now and I have some spare ones.
  12. If they agree to send the batteries your way try to get a few more. The point soldering is poorly done. I had to solder a few contacts because I was getting intermittent readings on the multi-meter, and a couple of batteries exploded in the process... I reordered and even when the seller is pretty close to my town it takes around a week to get the batteries in the mail.
  13. Well some people on this forum has been nice to answer my questions before so I'll share that info now. https://www.ebay.com/itm/2pc-9-6V-Custom-NiMH-2100mAh-Battery-for-Pk-6-Bare-Lead-NT8JY-Futaba-4NBL-BF-BP/272062528085?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649#shpCntId And for those who are not DIY oriented, I'm going to have those batteries for sale soon, so they can just insert them in their camera and start shooting. It will include charger 🙂
  14. I purchased two packs of batteries. They came soldered from the manufacturer, so I just used another connector (Thin, flat metal) from another rechargeable battery that I had and all set. The problem that I have right now which is not big is soldering the cables to the terminals before I screw the onto the plastic case, but I'll figure it out.
  15. Thanks for doing that Gareth, Well after a lot of time trying to find the parts and a lot of work, I'm almost done with my new battery. It has 16 AA, 2200mAh rechargeable batteries and I'm going to add a 30A fuse as specified on the camera's manual.
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