Oscar Spierenburg
March 20th, 2005, 10:12 AM
I thought about another existing 90° mechanism. How about a guitar tuning mechanism. Or maybe on for a contrabass or something.
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Oscar Spierenburg March 20th, 2005, 10:12 AM I thought about another existing 90° mechanism. How about a guitar tuning mechanism. Or maybe on for a contrabass or something. Dan Diaconu March 20th, 2005, 03:03 PM http://www.qtcgears.com/e-store/DPGears.htm Oscar Spierenburg March 20th, 2005, 06:03 PM Bottom left: Worms & Worm Gears, is exactly a guitar tuner. Dan Diaconu March 20th, 2005, 10:01 PM yes......but are you changing careers? is it not 3 or 4 more suitable for FF? Could you rack from one end to the other of the lens in one second using the worm gear? (without a motor that is) Oscar Spierenburg March 21st, 2005, 07:08 AM Dan, you'd better tell me. I was just wondering what could be used and is ready made (and not expensive) So if you turn the first axes, the second one (after 90°) should turn in the same amount, or more? Dan Diaconu March 21st, 2005, 08:33 AM "Dan. You’d better give me a fish and don’t teach me how to fish".... It is all a matter of ratios. What is the gear diameter on the lens? How much is active (out of it)? What is the gear diameter on the engaging gear?... In how many turns should I turn from close to >< (infinity)? In one turn or less. Say you have a 90mm dia on the lens and close to >< is spread on 180 deg (so, only half) Equivalent dia of the lens is? 45mm. Now, if your engaging gear was 45 mm dia, you would need a 1:1 ratio in the miter gear. Right? But if you do not have the exact above figures, how should I know what would work to lead you to the desired result? Start with gear on the lens and the engaging gear of the FF, the rest will follow. Now you can go "fishing".... If the two lens (filming and viewfinder) were counter rotating from close to >< you could figure two diameters that will engage with each other and keep the distance in sink (but that would be toooo much to calculate...) Oscar Spierenburg March 21st, 2005, 10:36 AM Can you make that a fried fish instead? I was just asking stupid questions find a way for many people, not only me(I have a weird setup anyway), to get the basic elements of a FF from ready made stuff. So the best thing to look for is probably a 1:1 ratio (It looks like that's what Cosmin used) I also wonder how a professional FF deals with different lenses? Dan Diaconu March 21st, 2005, 11:21 AM >>>>>Can you make that a fried fish instead?<<<<< Sure can. what would you like on the side signore? *smile* and relax, no pun intended...hey?*smile* and enjoy the ride. >>>>I also wonder how a professional FF deals with different lenses?<<<<< Derz an artuc.... arctic.... hmmm ... an arm... that moves in and out to reach different lens diameters. Recent lens designs like Zeiss superspeed have the same dia at the same distance from the mount (aint that swell?)*smile* life is short. (......hmmm....artuculite?) Oscar, der aint no stupid questions, OK? Is just that there are too many variables to provide a "formula" that works. I forgot to add, you should consider the distance from "rods" to lens as well. (the nightmare's just B gun) I want to make sure you understand I admire your 2 camera idea and implementation as well as all the hard work involved to make it happen. I did not make fun of you OK? Just average, "no name" entertainment...*smile* (I like that) Oscar Spierenburg March 21st, 2005, 11:56 AM Right! Make that "Dan, you’d better give me a fishing rod in stead of a fish" ...maybe I can make a FF out of it. Many thanks for your replies, you know a lot. I'll be experimenting with this in a few days. For me, thats always the best way. Rafael Cruz March 21st, 2005, 01:33 PM first i think that Dan Diaconu's work is amaizing , and i really wan t to try to make a FF , i have this miter gear that i think could be modified, also my rig is an fx1 with a mini35 i have the original 15mm rods of the adapter but i also made 2 long aluminum rods to support a long argeniux zoom lens, maybe i could use the argeniux arri base for the FF as well , Dan let me know what you think of the gear that i have: http://www.reggaetonmusictv.com/mitergear/miter_gear_ruler.jpg http://www.reggaetonmusictv.com/mitergear/miter_gear_side.jpg http://www.reggaetonmusictv.com/mitergear/miter_gear_bottom.jpg Dan Diaconu March 21st, 2005, 02:00 PM But I ain't got no fishing rods nor fish here (somthg's fishy though) ....always good for a laugh.... thanks guys. almost 4goat : *smile* Now: I'd still go with the CMOS thing (in your shoes) and a FF for one lens only. You'll make it somehow, I know. Rafael, all you may need is da right (or the left?) gear to go on the lens (instead of the one mounted now) or you could engage that one to another one to go on the lens and you're there. What you have for 15mm rods might be the best thing you need to mount it. Good luck. Daniel Skubal March 21st, 2005, 02:07 PM Has anyone considered a "strap on gear" for the lens ring?... something similar to a zip-tie but with larger teeth? I don't even know if they make them but it'd definitely be worth looking into. Just standardize the teeth, and then you can build an any-camera follow focus without having to worry about the lens ring. Rafael Cruz March 21st, 2005, 02:11 PM great, thanks Dan, also i have canon ef and nikon still lenses to use with the mini35. is it better to fix some kind of gear ring to them? are this rings comercially available? what could i use for it ? what about plastic ones? Daniel Skubal March 21st, 2005, 02:30 PM You can order these rings from the manufacturers of pre-existing products, but the rings sell for between 100-200 dollars. Plus, if add on a micro35 or any lens for that matter, the ring becomes useless and you have to buy another one to fit that specific lens. I would much rather have a disposable/adjustable strap to save me from that problem Dan Diaconu March 24th, 2005, 12:24 AM Rafael, the Nikons I have mod have four different dia (out of seven lens) so, I had to do custom fitting rings. However, the outer dia I made is the same for all. A pain, but awesome to work with now. I also had to take them apart (one by one) and re-do the greasing job which was good for still lens but not adequate for "in take" focus roll speed (they were stiff) Now, they have the Zeiss moves....hehehe.... Same for a FF I played with today. Made in China, sold here for $ Can 1200 (about US$950) Stiff (well... compared to the one I made and the standard) and therefore solicitting in use. (small "details" that add up when one looks at a certain product and questions the price like I do) There were other two inconveniences but I would prefer to move on and follow Shannon's advice and make one (the way I would like to use it) available for a decent price that will address those issues as well. Working on it.... Matt Kelly March 27th, 2005, 11:02 PM <<<-- Originally posted by Daniel Skubal : Has anyone considered a "strap on gear" for the lens ring?... something similar to a zip-tie but with larger teeth? I don't even know if they make them but it'd definitely be worth looking into. Just standardize the teeth, and then you can build an any-camera follow focus without having to worry about the lens ring. -->>> What about nylon or thin plastic rack (& pinion) gears? Do you think you could get one flexible enough that you can just bend it around the lens and you could either glue it or screw it in place? If there was anything like this, then you could probably make it into something that can be strapped onto any lens, like daniel's saying, but i'd think it would need some hella grip to keep from slipping around. Daniel Skubal March 27th, 2005, 11:39 PM <<<-- Originally posted by Matt Kelly : <<<-- Originally posted by Daniel Skubal : Has anyone considered a "strap on gear" for the lens ring?... something similar to a zip-tie but with larger teeth? I don't even know if they make them but it'd definitely be worth looking into. Just standardize the teeth, and then you can build an any-camera follow focus without having to worry about the lens ring. -->>> What about nylon or thin plastic rack (& pinion) gears? Do you think you could get one flexible enough that you can just bend it around the lens and you could either glue it or screw it in place? If there was anything like this, then you could probably make it into something that can be strapped onto any lens, like daniel's saying, but i'd think it would need some hella grip to keep from slipping around. -->>> Do they make gears like that? For most lenses, the built-in focus ring is rubber, so if you could just make a locking mechanism like a watch (where it folds back and clips in), or maybe even just a pin system... I'm no engineer but I believe standardizing the gear strap and making it adjustable would be optimal for making a DIY FF Also, the gear strip wouldn't be required to go all the way around because most focus systems only have a 120-270 degree turn radius, so as long as the strap device was opposite to the ff gear, there would be no confrontation. Matt Kelly March 27th, 2005, 11:55 PM This is the sort of thing i was thinking about http://www.machined-plastic.com/rack.htm The green gear isn't the best example, but i bet something similar to it could work. Daniel Skubal March 28th, 2005, 12:42 AM Ohh! Yeah I think that would work... that was actually what I was "looking" for when I originally posted the idea. Hmm... I think this may be something worth pursuing. I mean... a 1$ piece of plastic versus a 350$ crafted product... I think it's worth a try. Matt Kelly March 28th, 2005, 12:53 AM Well if you want to try it, go for it. I'm definitely going to try my hand at building a set of rails for a follow focus, but at the moment i'm working on a mini35 adapter first... so it'll probably be weeks before i plan out measurements and gear ratios for the follow focus. Lemme know if you have any progress. Also... any tips on making a follow focus? I've seen some homemade ones involving miter gears, but i have no idea if they work anything like the real thing. i.e., one hand turn of the follow focus should pretty much give you full range of focus turn on the lens. don't know much about gearing either, other than what i've done with legos. :) Oscar Spierenburg March 28th, 2005, 05:42 PM <<I also had to take them apart (one by one) and re-do the greasing job which was good for still lens but not adequate for "in take" focus roll speed (they were stiff)>>> Dan, is any normal grease fast enough for an FF. I wonder if it is grease in (slow) lenses. I searched a long time for the right grease to redo my arri tripod head. When I put sticky resin instead of grease, it gave exactly the slow moves it needs. Is it resin they put in there originally? Dan Diaconu March 28th, 2005, 10:20 PM The "ideal" FF (as well as the "blamed" as expensive ones) should not have any more friction than required in the bearings (not much) The Cavision that I have looked at was stiff (when compared to "normal") That alone (aside from stiff lens) can make the difference between being "soft" or slow to reach focus and "right on" during a "fight scene" or fast moving objects in and out (towards and away) from the lens. The resin in the head is OK (for a while) as the closest to original. In the lens, there is "normal grease" for the job they were meant to do. However, that makes them "slow" compared to the way the cine lens turn. I had to clean them all with WD40 and replace it with some stuff I saved from other mechanisms I had worked with. I am sure there is commercially available somewhere, but I did not need, so I do not know. End result is what matters and they turn EASY. Brian Valente May 19th, 2005, 10:49 PM Hi Everyone, I am adding to this post to inform you Redrock Micro (the micro35) is intending to build a low-cost, high quality follow focus. We are soliciting input from you on what you want in this product. We have already started a thread on input that can be found here: http://redrockmicro.com/forum/viewforum.php?f=15 We hope you will visit and tell us what you want. Redrock's intention is to offer this to digital filmmakers everywhere with the philosophy of high quality products at revolutionary prices. Those of you who are familiar with the (soon to be released) micro35 can fully appreciate what this means. Thanks Brian Courtney Lana May 20th, 2005, 02:51 AM Alls i'm sayin' is dis..........If someone comes up with a DIY way to make a follow focus that FUNCTIONS the way a follow focus should, and makes the plans availbale........they will be sittin' pretty. And I don't understand why nobody has not done this yet. People always complain about wanting an Internet Business and don't know what to do?? Well here it is...here's your opportunity. Shannon put it out there for you. That's alls i'm sayin' *smile* - Shannon W. Rawls Most of the problem comes to the fact that most people of here don't know how to machine. So they have to take their design ideas to someone and let them create it. Machinist charge, I'm sure, alot. I don't know exactly, but I'd guess at least $60/hour. Fortunately for myself, I've got many years experience in machining. This past week I've been buying metal and various other things to do a few projects, one of them a 35mm adapter. Another one is a rail system - no big deal there. Another is a matte box with barn doors and a filter holder. Another is a follow focus and yesterday I picked up 50 bright white LEDs (at 15000 mcd a piece) to make one of those LED cam-lights....kinda like the light rings that are made now. I was surprised at what aluminum costs. My first outting I picked up some at a scrap yard for kinda cheap. About $0.70 a pound. Two days ago I picked up some for $0.35 a pound and I'm going back for more. Also picked up some stainless rod, 1/2" dia., for $1 a pound. So far I've spent under $20 for material and I've got enough to do most of these projects. Now I just have to sit down, plan, and start machining. Like I said, lucky for me I know how to do all this stuff. But if you were to pay someone to machine it for you, I can see very quickly how the price skyrockets in no time flat. Court Robin Davies-Rollinson June 27th, 2005, 08:51 AM These are a couple of pix of the follow-focus rig that we made up for the FX1. It uses a "strap" gear mounted on a specially machined alloy holder. The right-angle gear drive was purchased from Maplin UK for only 17 GBP!!! http://img.photobucket.com/albums/v137/robind-r/Followfocus1.jpg http://img.photobucket.com/albums/v137/robind-r/Followfocus2.jpg Robin Daniel Skubal June 27th, 2005, 10:25 AM Oh wow! How is the motion on it? Pretty smooth? What about the strap gear? Where'd you find that at? All-in-all, how much did the ff cost? I assume the machined alloy drove the cost up quite a bit Robin Davies-Rollinson June 27th, 2005, 10:40 AM The motion is very very smooth - and makes finding focus a breeze. Especially as you can set up a mark and return to it (which after all is the point of the rig...) It only really cost me 18GBP and a few bottles of wine, since I had it made up by a pal in the BBC mechanical workshops here in Cardiff. He takes a real delight in making up bits of gear like this. My next project is to try and interest him in a mini-35 adaptor .... ;-) Robin Aaron Shaw June 27th, 2005, 02:19 PM Very cool! Any chance you could post your design? I'm sure others would be quite interested. Robin Davies-Rollinson June 27th, 2005, 02:58 PM Aaron, I'll do my best. There weren't any real drawn-up plans, merely a case of adapting bits and pieces that were available to us. The hardest bit (at least, I thought it would be..) was to find the right-angle gear drive. I did a Google search and came up with : THIS (http://www.maplin.co.uk/Free_UK_Delivery/Bevelled_Gearbox_43541/Bevelled_Gearbox_43541.htm) Once we had that, it was just a case of mounting it to the 15mm rods that I already had for the Arri matte box. We found a spare slider for the rods and machined a block to hold the gearbox, with slots to allow the gears to be moved up to the lens gear ring as required. I'll take some more pix as soon as I get a chance to show the parts in more detail. I'm very happy with it and have already been using it on some docs that I'm shooting for the BBC as well as for one of our commercial channels. Robin. Aaron Shaw June 27th, 2005, 04:16 PM Awesome :). I know how building things goes so no worries! Eniola Akintoye September 8th, 2005, 04:46 PM So is it possible for you to make some for different camcorders and sell?????. A lot of people can not afford $800 for a FF which I presume is the price for cheap ones. With the enormous amount of Indie guys looking for cheap camera accessories, could you make some and sell? With a price of like $70 or something, I think it would not be bad adding some 5 zeros to 6 zeros in your bank account....what do you think? Also in regards to the adapter, what have you been able to come up with? Dan Diaconu September 8th, 2005, 06:15 PM You may be interested to get a closer look at this items: http://dandiaconu.com/available_products.htm Leo Mandy September 15th, 2005, 02:31 PM I am also interested in the cheap design system. Going to look for the mitre joint tomorrow! Also Dan, is there a reason you used the redish blossom knob for your kit? Giroud Francois September 15th, 2005, 04:02 PM ok , lets be creative. the problem: so many lenses, so many diameters. forget about gears, too difficult to pruce, almost impossible to get one size fits all. solution: Gear belt. just cut the length needed to wrap your lens. need to fix it ? use velcro. no need for a pulley yet. you just need a second gear belt that goes over the one on the lens. they are theeth over theet on a big length so no risk for slippage. the width of each belt can cover even the biggest displacement of lens. now the pulley. Again for universal mount we will do it in a way it has an adjustable position so you can make the belt streched (tended ?) properly. The rest is easy, you can use any right angle (but do we absolutely need right angled ?) device you will find to transmit the rotation to the button. (i have seen really nice plastic gear for potentiometer). some cheap plastic motor offers good source for right angle shaft http://www.hobbyengineering.com/SectionM.html#IX1209 and Dremel has is own http://www.hobbylinc.com/htm/dre/dre575.htm if you relly wants gear, see alltronics http://www.alltronics.com/images/23Z027.jpg for 5$ this stuff is more than 3 inches diameter. Dan Diaconu September 15th, 2005, 05:53 PM [QUOTE=Mandy Leo Also Dan, is there a reason you used the redish blossom knob for your kit?[/QUOTE] http://www.speedtv.com/_assets/library/img/large/55271_lexus.rx.interior.web.jpg http://www.cars.com/features/2001overview/lexus/images/ls430_interior_292x178.jpg http://www.rodmillen.com/images/Concept/Lexus_interior.jpg http://www.aaton.com/galbums/cameras-high-rez/xtr_prod_front.jpg http://www.filmcamerakit.com/Pictures/Cameras/Aaton/Aaton%20LTR%2032.jpg http://www.dvinfo.net/sony/images/cinetech/cinetech3.jpg http://www.dvinfo.net/canon/images/cinetech4.jpg http://www.dvinfo.net/canon/images/cinetech7.jpg http://www.dvinfo.net/sony/images/cinetech/cinetech1.jpg 'nough? I guess is only a matter of taste. I like wood (blasphemy in a plastic and Al world, I guess...) but plastic and Al knobs are almost finished. Noah Yuan-Vogel September 15th, 2005, 09:26 PM for those of us looking for a really cheap solution, I was at the hardware store today and noticed a $15 hand drill that transfers rotational motion like a bevel gearbox would. I'd imagine there is a way to mount it and attach a gear to go together with some kind of gear band on a lens. Just an idea. Anyone know where to get some kind of strap with gear teeth on it? Plastic ties like the ones that you slide through a hole on one end and have to be cut off have some notches in them, so maybe something like that could be strapped to a lens? Someone mentioned such a thing, but I am not sure where to get them. If they are cheap you could just attach one to each lens and leave them on. Wayne Morellini September 16th, 2005, 03:04 AM Good thinking, when ever it breaks, throw it away and put another on for a few cents. That would make it cheap to do for zoom and iris as well on a SLR lens. The ring tie straps should be in office stores, and various trades stores that use them, I forget where I got mine from. The nob on the strap could also be used as a leaver that could hit stops for direct hand control. For instance, mount one main strap and cut to knob, mount another secondary strap next to it with some sort of attachments (even more micro ring tie loops) sticking out over the main strap, that the knob will hit for a stop. You could even use ring tie loops as adjustable stops. But it would depend on the lens configuration allowing it. Diagram top view (laid out flat, because of no curves in text graphics): Secondary strap with main stops "()" and adjustable stops "(o)" over lapping main strap (),,,,,,,(o),,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,(o),,,,,,,,,,,,,,,,,,,,,() (),,,,,,,(o),,,,,,,,,,,,,,,,,,,,,,,@,,,,,,,(o),,,,,,,,,,,,,,,,,,,,,() Main strap with "@" knob. You could make the adjustable stops by tyeing two straps on top of each other on the secondary strap, one tight on lens and the other loss to allow the stop rings to slide, both firmly tied to each other by loops used as the main stops. Like this (side view of secondary strap) (),,,,,,,(o),,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,(o),,,,,,,,,,,,,,,,,,,,,() (),,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,() Leo Mandy September 16th, 2005, 07:28 AM Isn't there a worry about using electronic and battery powered motors (dremels or otherwise), that you are going to strip the gears in the SLR or the gears that are purchased? Oscar Spierenburg September 16th, 2005, 07:53 AM Just a thought I had some time ago: If you put a flexible axes (from a dremel or another drill) on one side through a ring that mounts on the non moving part of the lens, so it is parallel to the lens, and you put a gear on that end of the axes that touches the lens (with a strap on it), so if you turn the other end of the axes, the lens would move with it. Because the thing is flexible you can mount the other end ( with a knob and markers) anywhere you want, like on the tripod or in the hands of a focus puller. If this is not clear at all, I'll draw it. Giroud Francois September 16th, 2005, 09:02 AM i found it back... http://www1.conrad.de/xl/1000_1999/1800/1830/1839/183992_RB_00_FB.EPS.jpg about 20$ but goes around 10$ if you order at least 20 more info at the bottom of this PDF http://www.produktinfo.conrad.com/datenblaetter/175000-199999/184007-da-01-ml-Umsetzer_649_66_de-en.pdf Giroud Francois September 25th, 2005, 12:18 PM just received the part for my cheap FF. some pictures here big plastic potentiomenter button with mark http://www.giroud2.com/divers/button.jpg http://www.giroud2.com/divers/scale.jpg the right angled drive (6mm axis version) http://www.giroud2.com/divers/angle.jpg the full stuff with a pvc rod and metal parts http://www.giroud2.com/divers/full.jpg will add a pulley and some gear belt, et voila... Obin Olson September 25th, 2005, 08:29 PM good, looks like we have a taker, go man go...if it works on the Letus setup with the micro35 rail system I will buy it..I need one bad..;) make sure it works on Nikon 35mm lenses Leo Mandy September 26th, 2005, 07:19 AM Looking great. I found an old printer on the weekend with the turning knob, I am going to use that and I am looking for the gears as well! Are you going to do a tutorial for this? PArt lists? Suppliers and all that jazz? Giroud Francois September 26th, 2005, 10:58 AM basically , if you are going to the easy way (buy parts and assemble them), you should stick to one technology (the electronic potentiometer in my case), because all parts are sharing the same sizes. You can find thousand of button for potentiomenter with 6mm standard axis and most of time you do not even need to buy them, just find some electronic surplus. look at http://www.conrad.de (where i order my parts) and on top of screen paste these numbers into the field "Artikelnr.-Suche" 184007 183731 183504 183771 183797 You need to add a white plastic disc (for the marking), a 3 inches of aluminium corner to mount all the parts, the gear and gearbelt, few screws. The deluxe version would add a little motor (i already found one in my drawer, but the origin is unknown, so cannot purchase more). i am sure that goldmine-elec should have the little marvel. for sure you can find equivalent or same parts/supplier anywhere in the world. Yes ideally, somebody would build one kit to proof feasability and then order all parts in big quantities (50 or 100 items) to build a kit with instructions. unfortunately, even if the kit cost only 50$, it makes 50x50=2500$ +overhead to manage orders and send kits. It is for instance out of my capability or my will. David Delaney March 8th, 2006, 07:49 AM Richard, how exactly did this work? I can't figure out how the strongboy gives you the 90 angle? I use this on a homemade 35mm adapter, with a canon 1.8 lens. It fits right in with the under $200 total cost . shallow depth of field on minidv for less than $200. http://www.tabletools.com/tabletools/showdetl.cfm/595/zyliss_strongboy.html |