Carl Looper Posted September 1, 2013 Share Posted September 1, 2013 (edited) This is a Forum (designated space for public expression), the people are here to discuss, whether its a Prof., student or child... And should not be the place for personal unnecessary hustle and bastle, please guys... Yeah, I don't know if Benjamin's gonna come back. He got pretty angry with me. I'm assuming the penny finally dropped and he got the picture. I hope so. He'll be far better off with a correct model of what's going on rather than all that rubbish about crop/format factors that he otherwise finds so compelling. The irony is that a crop factor is designed to actually undo the error which results from misinterpreting focal lengths as corresponding to a field of view. An alternative to crop factors is just not to entertain the error in the first place. And even if maths isn't your cup of tea, there are some rules of thumb (that follow from the math) you can use without any maths at all. 1. All lenses of the same focal length (regardless of the format for which the lens was otherwise designed), will give the same field of view, when used on the same camera. So for example, if, on a Super8 camera, a 15mm lens designed for that camera seemed like a normal lens to you (through the viewfinder), then you can interchange that lens with any other 15mm lens, made for any other format, and it will give you (shock horror) the same "normal" angle of view: the one you thought of as a normal one. And if a normal lens to you, on a Super8 camera, were actually 7mm, nothing would change. Every 7mm lens you put on the Super8 camera will give back to you a "normal" angle of view. It is for precisely this reason I said it doesn't actually matter what you consider normal. If a 100mm lens, on a Super8 camera, looks normal to you, then 100mm lenses are the ones you should use. The only cavaet is that if the lens was designed for a smaller format the resulting image might not completely cover the Super8 frame. 2. Any lens, regardless of focal length, and regardless of the format for which the lens was otherwise designed, does not have a field of view. What? Yes. A lens doesn't have a field of view! This is probably the hardest one to get one's head around. The reason is that field of view is not a property of the lens. The focal length of the lens controls the size of the image that is otherwise falling on the film/sensor. It doesn't control field of view. Field of view is a result of using a frame of a particular size that crops the image. But insofar as you can't readily vary the size of the film (!) you can vary the focal length instead. Has the same effect. This is why you can't put field of view markings on a lens, because the lens doesn't have a field of view. It does, however, have a focal length, so one can put the focal length on the lens. Indeed on a zoom lens, without focal length numbers printed on it, you wouldn't even have any way of looking up a correpsonding angle in your look up table. To what lens setting would any of the angles correspond? Or reciprically you would have no way of setting your zoom lens according to any angle you've looked up in your look up table. C Edited September 1, 2013 by Carl Looper 1 Link to comment Share on other sites More sharing options...
Carl Looper Posted September 1, 2013 Share Posted September 1, 2013 The focal length of the lens controls the size of the image that is otherwise falling on the film/sensor. It doesn't control field of view. Field of view is a result of using a frame of a particular size that crops the image. But insofar as you can't readily vary the size of the film (!) you can vary the focal length instead. Has the same effect. I should really say that it is both lens and frame size that control field of view. Neither a lens, nor frame size, on their own, controls field of view. Carl 1 Link to comment Share on other sites More sharing options...
Erkan Umut Posted September 1, 2013 Share Posted September 1, 2013 Carl, many thanks for your invaluable posts! You know this business very well, I have no doubt for it! What you can do is to write a simplified book about optics. Will be perfect for us interested in optics and wanted to go deep. Why not? Many books about the subject are f*cking difficult for filmakers, except some good webs and papers... Link to comment Share on other sites More sharing options...
Carl Looper Posted September 2, 2013 Share Posted September 2, 2013 Carl, many thanks for your invaluable posts! You know this business very well, I have no doubt for it! What you can do is to write a simplified book about optics. Will be perfect for us interested in optics and wanted to go deep. Why not? Many books about the subject are f*cking difficult for filmakers, except some good webs and papers... Yeah - a book that would be cool. While I might be okay with optics, I'm not so hot on mechanics - still learning. I still recall the day (not that long ago) I postulated a completely incorrect model of how a claw mechanism worked and Dom Jaeger pulled me up on it and as I recall I got pretty angry with him. Not about the mechanics (Dom was entirely correct) but the way he put me in my place, which got my back up. But that side of things passes. What is more important is the information. And Dom knows what he's talking about. And I didn't. C Link to comment Share on other sites More sharing options...
Carl Looper Posted September 2, 2013 Share Posted September 2, 2013 Here's an interesting problem. And my apologies in advance for not posing any problems in relation to mechanics or the new Super8 camera. The horizontal field of view, of the human eye, is almost 180 degrees. (ref. http://en.wikipedia.org/wiki/Human_eye#Field_of_view) Why then don't we see, in everyday life, the "extremely converging lines" that we otherwise see in photographic images made with fields of view far less than this? The answer is that the photographic image is being re-transformed within a second optical system - that of the human eye (and brain) of the audience. The eye is an optical system and can be taken into account. There is the particular perspective (field of view) of the camera, and then there is the additional field of view (of our eye) in which the camera's field of view is being re-observed. To restore the image to an otherwise matched perspective, all we have to do is move our eyes in closer to the image until the image frame on our retina matches the same field of view that the camera had. The result of this adjustment is that the image will no longer possess what we might have otherwise described as "extremely converging lines". We would have to stand further back again to restore that sense of hyper perspective. And all of this is done without in any way altering the original photography or the photographic image. We are just altering the optics of the last stage - the relationship between eye and photographic image. In other words the perspective/field of view is not just a function of the lens and film format but also a function of how close or far way we are when observing the result. Are we sitting up the front of the cinema or the back? Are we right up close on our computer monitors or further back. One will get a different sense of perspective as a result. What is actually more interesting than any notion of "normal" perspective is changes in perspective. Differences in perspective. For example, going from a wide angle view to a tighter view. Or vice versa. Someone up the front of the cinema will appreciate this difference/change as much as someone up the back. Carl Link to comment Share on other sites More sharing options...
Carl Looper Posted September 2, 2013 Share Posted September 2, 2013 Of course a filmmaker such as Ozu almost exclusively used the same field of view for all of his shots. He didn't like changes in field of view. What he did like was "upsetting" your orientation with respect to the world he was otherwise creating. Upsetting your point of view rather than your field of view. But it was incredibly well structured "upset". He'd rearrange the scene, from one shot to another, in such a way that you couldn't tell quite tell it was altered. The result is that you couldn't quite locate yourself with respect to the scene. But this wasn't the objective. At the same time the scene would maintain a complete sense of narrative continuity. Indeed it even appeared to have complete spatial continuity. The real result was a sense in which one achieved a kind of transcendental view of the unfolding scene. One was transformed into a kind of spirit, as if in multiple places at the same time, rather than in different places at different times. C Link to comment Share on other sites More sharing options...
Alan Rencher Posted September 2, 2013 Share Posted September 2, 2013 Please move this discussion to a different thread. Everytime I come back, I try to look for the posts regarding the camera, but all I see are the focal length / format debate over several pages. 1 Link to comment Share on other sites More sharing options...
Carl Looper Posted September 2, 2013 Share Posted September 2, 2013 The discussion on focal length/ format was to resolve questions around lenses for the new camera. I suspect that discussion has completed. Here's Lasse's contribution - for which you might be looking: Hi All, It's incredible how much this thread has evolved during the last month or so - thanks for the many replies it confirms us in the belief that there's a need for a new camera. I'll keep replies short and to the point this time as I'm travelling abroad. We will only do C-mount. CS mount is not an option due to the design of our 45 degree oscillating mirror shutter. The other mounts mentioned will not be implemented either due to lack of space etc. We have tested the following lenses with our camera so far... Schneider Optivaron 6-66mm Zeiss Tevidon 10mm Cooke Kinetal 9mm Pentax 8-48mm For those interessted in buying used lenses I can reveal that we actually bourght the Schneider lens on eBay for a bargin and had that collimated later on. Regards Lasse Link to comment Share on other sites More sharing options...
Matt Stevens Posted September 10, 2013 Share Posted September 10, 2013 So resurrecting this thread... Many scanners do not have a wide gate, so the right section of the negative will but cut off in the scanning process for this camera. Pro8mm and Cinelicious, plus a few others, have widened gates for their scanners. But they are the most expensive places to go. Many will want cheaper options. So what needs to happen is the display needs to provide an overlay so that you can see where the 4X3 image is and understand where at the left it will be cut off. That way people can still shoot for 4X3 scanners or telecine bays. Is this making sense? I hope I am being clear. Obviously this would be a firmware thing die the display output. Link to comment Share on other sites More sharing options...
Erkan Umut Posted September 13, 2013 Share Posted September 13, 2013 So resurrecting this thread... Many scanners do not have a wide gate, so the right section of the negative will but cut off in the scanning process for this camera. Pro8mm and Cinelicious, plus a few others, have widened gates for their scanners. But they are the most expensive places to go. Many will want cheaper options. So what needs to happen is the display needs to provide an overlay so that you can see where the 4X3 image is and understand where at the left it will be cut off. That way people can still shoot for 4X3 scanners or telecine bays. Is this making sense? I hope I am being clear. Obviously this would be a firmware thing die the display output. Matt, This is making sense for sure! You got very good point. This is the pro way should be added... Link to comment Share on other sites More sharing options...
Lasse Roedtnes Posted September 13, 2013 Author Share Posted September 13, 2013 Hi Guys, You will have the option (in the settings menu) to choose from two different gate settings - with the wide gate you see on-screen a bigger rectangle of where the image will be - on the normal gate option you will see a smaller section as you would expect. Regards Lasse 1 Link to comment Share on other sites More sharing options...
Matt Stevens Posted September 13, 2013 Share Posted September 13, 2013 OK awesome. Great news. You are thinking of everything. :) Link to comment Share on other sites More sharing options...
Bill Rodgers Posted September 18, 2013 Share Posted September 18, 2013 Hi Guys, You will have the option (in the settings menu) to choose from two different gate settings - with the wide gate you see on-screen a bigger rectangle of where the image will be - on the normal gate option you will see a smaller section as you would expect. Regards Lasse Impressive stuff Lasse. :) Link to comment Share on other sites More sharing options...
Premium Member Dom Jaeger Posted September 18, 2013 Premium Member Share Posted September 18, 2013 Great work Lasse and your team, to have gotten so far. For what it's worth (2 cents?) my only suggestions would be to drop the pin registration and add an optical viewfinder. I don't know what sort of pin registration you're using (and never seen a high speed Mekel) but a sprocket-driven loop and pressure plate alone would be a vast improvement over traditional Super 8 steadiness, no need to introduce potential problems with film shrinkage or perf variation by using a registration pin. There's also the issue of added noise, unless you go to the extra expense of adding pitch control to the movement. But perhaps it's not a proper registration pin that fits the perf length, just a sort of stop pin to prevent the film advancing past where the claw positions it (which makes more sense for a high speed camera). Pulling focus off a video split monitor can sometimes be tricky even with state-of-the-art splits for pro film cameras. You need a very good camera in there to judge best focus, and a decent monitor. If you're outside in sunlight you need a deep shade to see the screen. It seems a bit crazy to have a reflex mirror without an optical finder. A simple rotating prism or mirror could switch between viewfinder and monitor out if you wanted to avoid the traditional split prism. Link to comment Share on other sites More sharing options...
Lasse Roedtnes Posted September 18, 2013 Author Share Posted September 18, 2013 Hi Dom, Thanks for your view. It's true that old films, for example from the freezer, can shrink and thereby cause jamming in the mechanism however we have not had any issues with the films we've been using so far which have all been new films from Wittner/Kodak. The trouble with optical viewfinding is that we considered this too complex/expensive to make since it involves many optical components and you also need to have diopter adjustment for people with glasses etc.,but more importantly the current design has been underway for several years now and we had to draw the line somewhere to finish the product - otherwise it would be "just a never ending pipedream" like some people stated, a one off prototype which couldnt be manufactured in volume. What we have now on the other hand is a design that can actually be manufactured and is designed with that in mind. Best regards Lasse 2 Link to comment Share on other sites More sharing options...
Anthony Schilling Posted September 18, 2013 Share Posted September 18, 2013 I've ignored this thread long enough thinking it was another pipe dream. But am quite happy and suprised to see something materializing. I don't know how much I would pay? but if it makes it to production, I will probably have to have one. I like the registration loop which is essential for professional shooting. I like the crystal sync and quiet motor for sound, and i like a wider gate. The things i would like to see are slomo between 54-64fps, and instead of a built in intervalometer like a lot of the older cameras... just having a jack that can run with any intervolometer. Also the ability to have open shutter for time exposre would be nice. As far as sound goes, That's cool that you can record audio with the camera itself. I'm not sure what the sound quality would be but will come in handy for certain things. I guess if you decide to record with a seperate unit (I just ordered one last night) you have crystall sync and a quiet motor and that's great too. Link to comment Share on other sites More sharing options...
Erkan Umut Posted September 19, 2013 Share Posted September 19, 2013 If you still need for an optical VF, then you have a limited alternative using the zooms having own VFs like Angenieux, etc. Please bear in mind that these optics are quite old, e.g. might have contrast loss and coating problems due to their age. Link to comment Share on other sites More sharing options...
Nicholas Kovats Posted September 19, 2013 Share Posted September 19, 2013 Check out this pricey alternative to the "dog ear" optical viewfinder concept as referenced by Erkan. P+S Teknik actually made an optical viefinder in a Sony B4 bayonet mount (FFD = 48mm). Another forum member, Alexander Kirch had previsouly posted his own unit for sale this past spring. It eventually sold for just over 1,000 EUR (9,000 EUR new) i.e. http://www.aa-w-transfer.de/download/IMG_7568.JPG MTF Services (UK) manufacture a B4/C Mount (FFD = 48mm/17.52mm) adapter, i.e. http://www.lensadaptor.com/b4-23-c-mount-adaptor I would recommend a 15mm rail system with lens support for such a setup. If you still need for an optical VF, then you have a limited alternative using the zooms having own VFs like Angenieux, etc. Please bear in mind that these optics are quite old, e.g. might have contrast loss and coating problems due to their age. 1 Link to comment Share on other sites More sharing options...
Nicholas Kovats Posted September 19, 2013 Share Posted September 19, 2013 Here is an Australian YouTube video illustrating the P+S Technik B4 optical viewfinder in action, i.e. This precision optical viewfinder (OVF) replaces the entire standard IMS to B4 assembly also manufactured by P+S Technik. Here is a picture of forum member Alexander Kirch's personal unit, i.e. http://www.aa-w-transfer.de/download/IMG_7563.JPG Note that P+S Technik employs former Arriflex engineers. 2 Link to comment Share on other sites More sharing options...
Nicholas Kovats Posted September 19, 2013 Share Posted September 19, 2013 I am not sure of the exact dimensions of the Lilliput monitor depicted in Lasses's original posting but check out the P+S Technik Universal Finder Option for 5-6 inch screens. It has diopter adjustment i.e. http://store.pstechnik.de/home/finder-option-for-5-6-displays-loupe/ While not optimal relative to a WYSIWYG OVF it does improve focusing/framing for the operator. I would recommend a higher resolution mini-LCD screen than the "stock" Lilliput referenced above. 1 Link to comment Share on other sites More sharing options...
Erkan Umut Posted September 20, 2013 Share Posted September 20, 2013 By the way, I am not familiar with the "dog ear"s. The external VFs might cause the problems due to camera body dimensions. Also, the old dog ears might split the light beams heavily, causing the loss for the transmitting optics to monitors, thou this might overcome with the gain increase, when the both are used. Instead of utilizing the registration pin, the "claw retardation" might be an affordable alternative. If the claw rests well enough time during the standstill period while the shutter is open for the exposure, it will act as a reg-pin, very old solution for easier mechanical design (like ARRI 35, 1937, etc.). Why reg is important? You gonna show your picture on big theaters' large screens. Super 8? The tests show that up to about 80fps will cause no problems in a compact camera for 35mm film, as ARRI released the 35 IIC HS model. Then, the thickness of the film gate, the lateral and side guides, the pad pressure all should be applied very precise. If you attempt to use an HS "snap-on" magazine on the regular speed gate or vice versa, you will get out-of-focus pictures for sure, thou this is not the case for the latent camera we discuss here. Link to comment Share on other sites More sharing options...
David Nethery Posted September 20, 2013 Share Posted September 20, 2013 By the way, I am not familiar with the "dog ear"s. I've always read it referred to as 'dog leg' viewfinder. 1 Link to comment Share on other sites More sharing options...
Guest Glenn Brady Posted November 11, 2013 Share Posted November 11, 2013 . . .let’s assume the following semi-professional camera existed on the market to be put under the christmas tree this year. It's a little more than six weeks until Christmas. Any news? Link to comment Share on other sites More sharing options...
Lasse Roedtnes Posted November 12, 2013 Author Share Posted November 12, 2013 Hi All, It's been a busy few weeks since our last update and time hasn't stood still ! We've been busy incorporating the great feedback we got from this forum - so big thumbs up to everyone that participated in making this the "people's camera" One of the most noticable things we've incorporated is an integrated side-monitor that allows for point and shoot operation without the "external monitor" so that the camera is not so bulky. Below you'll see the latest photo of our camera (with both external monitor and side monitor attacted) Please notice that the grey and red parts shown are 3D printed PLA plastic - this will be aluminium later on but to save time and cost we decided to 3D print these elements during our design phase. Because we need to have new parts made for the side monitor at our metal works partner and we are waiting for a new hardware revision to come back from assembly, we will sadly not make it under the christmas tree in 2013 (Unless christmas lasts till easter outside the nordics too) ;) We will be launching our webpage with more detailed information next month (December) there will also be links to two interviews we've given to respected german magazines where you can read more about us and our camera - we will launch our webpage together with the articles coming out. When launching our webpage you can expect to see sample footage shot with the camera as well as deep technical information and other cool stuff. There will (hopefully) also be videos that are not shot by us on the webpage together with their feedback on the camera's operation etc. - we are right now scrambling to pull everything together. Our goal is that the camera will be available for preordering in January/February via an escrow service such as Indiegogo or similar with expected delivery in March/April - we need to accept a minimum of 10 preorders in order to start production with our mechanical sub contractors as well as electronics subcontractors. As a special appriciation to those who preorder we will do a "one off" and allow people to have the camera anodized in either Red, Blue or standard Black (see below) - they will also get their name incorporated into the firmware upon booting the camera and if they please have their name/company name displayed on our webpage as people who helped this camera make it from being a "pipedeam" to a full grade production camera. We are right now targeting a pricetag of 2.500€ euro including 25% Danish value added tax - for companies purchasing inside the european union with a valid tax number that equates to 2.000€ euro. For sales outside the european union the value added sales tax is also removed, so the total should be 2.000€ euro (2.695$ USD) I know i've said it before but stay tuned! - It's going to be great Regards Lasse & Tommy 1 Link to comment Share on other sites More sharing options...
Matt Stevens Posted November 12, 2013 Share Posted November 12, 2013 More exciting news. I must say, it still seems like a fantasy that something like this could happen. But I guess it is. :) Link to comment Share on other sites More sharing options...
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