View Full Version : Totally Home-Made Oscillating Mechanism
Gev Babit February 25th, 2005, 03:43 AM This was all made at home with a $70 drill press and a home made lathe using a Wall-Greens $10 electric screwdriver. Here is some pictures and a video of the device in action.
http://www.papalico.com/rotoDrill1.JPG
http://www.papalico.com/rotoDrill3.JPG
http://www.papalico.com/Spinningplate.JPG
http://www.papalico.com/washers1.JPG
http://www.papalico.com/washers2.JPG
http://www.papalico.com/scale1.JPG
http://www.papalico.com/scale2.JPG
http://www.papalico.com/scale3.JPG
http://www.papalico.com/completedmech.JPG
http://www.papalico.com/completedmech2.JPG
http://www.papalico.com/completedmech3.JPG
Here is a video of the mechanism in action!
Small Version 11mb
http://www.papalico.com/Oscillatingsmall.mov
Large Version 24mb
http://www.papalico.com/Oscillating.mov
Brett Erskine February 25th, 2005, 04:12 AM Let me be the first to say congratulations! Its incredible you were able to make some of thoughs parts with that level of precision with a simple drill press and vise! I would have never been able to do that. It much have been a pain in the ass and taken a long time to do. So the big question....How well does it work in the end? Give us the details.
Is it quiet enough to still use the on camera mic or at the very least a boom mic close by?
I noticed that the GG mounting plate is pretty hefty. Is the extra mass creating a problem where it vibrates the whole camera slightly?
How did you find or create thoughs off set shafts that make the oscillating movement and what tools did you use to make three that were exactly the same?
How do you find the range of oscillating movement? Too big or not big enough or perfect to create a grainless image?
What the type of Battery? Motor?
Lastly can we see a short clip of some video shot with it?
Gev - great work!
Les Dit February 25th, 2005, 04:49 AM Looks cool so far!
Here is a good test to see if it will work : Run it and look at the side of the ground glass that is shiny(smooth). Use that surface as if it was a mirror, and look at something else in the room using that mirror with it running. Does the reflected image look perfectly still? Or does the image shake around a bit? If it's perfectly still, as if the motor was off, you are done ! If not, well, that's a show stopper.
-Les
Gev Babit February 25th, 2005, 05:23 AM Brett:
Hey thanks this thing took a long time I had to mill it with the drill. The piece that moves and with the ground glass has most of the aluminum cut out to keep it light. The shafts are made from regular stainless screws and they are soldiered together. To do this I made a template which sets one screw .7 millimeter off and then the two are tightened on the template and soldiered together. The template is very important because it makes everything precise and to ensure all the shafts are the same. The motor if I remember is from a vcr and is pretty quiet, there is very little noise but in the low mid range area so there is no annoying high pitch electric razor sound. There is some small vibration when you hold it in your hand but on a surface the vibration is almost fully gone. Its uses a 9v battery. I'll add some pics of the template and shafts.
Les: There is no movment on the z-axis as far as I can tell and this has been the main concern from building it in the beginning.
I have no footage shot cause there is no foundation and enclosure yet, I'm trying to make it so the whole mechanism moves to get the flange focal distance for various lenses. I'll try to get footage shot as soon as possible to post.
Gev Babit February 25th, 2005, 06:19 AM Here is the template used for making the shafts!
http://www.papalico.com/ShafttemplteCU.jpg
http://www.papalico.com/Templateoffset.jpg
http://www.papalico.com/screwsintempcu.jpg
http://www.papalico.com/mostparts.jpg
Leo Mandy February 25th, 2005, 07:52 AM Hats off to you Gav,
Utterly astounding. I could not do that if I tried, well made, it almost looks like it was factor machined! It looks like it works too - which is a huge step for use here because it opens up alot of doors! Keep us updated!
Sarena Valilis February 25th, 2005, 11:32 PM wow.... for the tools you had to work with DOUBLE WOW>>>>!!!
very nice job... your creativity on a budget is remarkable....
ive been finishing plans to do what you did and i have 4 mill and 2 lathes.... just havent gotten around to this project for myself...
but i must take my hat of to you and your creativity too...
only one or two suggestions to anyone who might follow in your footsteps.... harbor freight has cheap digital calipers on sale from time to time for around 15 dollars... might help those that dont have any mic's floating around... the second might be to try a TINY end mill instead of the drill bit... it might do the cut outs a little easier, but then again, you did a fantastic job without it....
im going to make my motor mount a little heavier duty. i am going to try and find some aluminum extrusion to use as a housing and just machine a lip around the edges of front and back plates to block light... (much less machining than tryin to machine a solid block....) hope some of this babble helps....
good luck and keep up the good work....
Gev Babit February 26th, 2005, 04:24 AM Thank you and I could not have done it without the help and influence of the people here that have contributed to this.
I didn't use a drill bit, hehe...It was a rotozip bit and dremel carbon cutter. If you look in the pictures you can see that its not a drill bit, that would have been very hard and would take a long time. Its very dangerous doing it this way so people who want to try it be careful, the secret is in the weight of the vice. To do milling you dont fix the vice on the drill press table, it moves freely, because of the weight the cutter doesn't move the metal. You move the vice very slowly toward the cutter and little by little milling it out. People who want to make the plates should use Duraluminum, it is very light and strong, don't use soft aluminum because it wears down.
Dan Diaconu February 26th, 2005, 07:06 AM So, ....... the madness is spreading faster than I thought!
CONGRATULATIONS!!!!!!!!!!!
You are there.
Les Dit February 26th, 2005, 11:24 AM So Gev, when are you going to shine a video camera through it instead of at it ;)
On my first version, I just hot melt glued the thing to a board with a lens rigged up in front of it. Works good for testing it out!
-Les
Gev Babit February 27th, 2005, 04:12 PM Thanks Dan but really thanks to the "Mini35 Oscillating Ground Glass Idea" thread.
Les I am working on it.......
Hey Brett what was the dust paint you were talking about in another thread?
I need to paint the mechanism and don't know what to use. I need something not shiny. Is it possible to find the paint they use for cameras?
Thanks,
Gev
Les Dit February 27th, 2005, 04:28 PM Gev, I recommend Krylon 'Ultra flat black' It's pretty much the least reflective paint that is still out there. The telescope people seem to love it for their construction projects.
-Les
Brett Erskine February 27th, 2005, 06:40 PM For most jobs I would go the easy and cheap route and do a ultra flat black paint like Les mentions but definately not with yours. You made yours out of smooth aluminum and paint doesnt like to stick to it even with a aluminum primer. The last thing you want is flakey paint in a device that normally needs to stay absolutely clean inside.
I plan on getting mine powder coated flat black when Im done. It looks real pro but more importantly it wont come off and ruin your shots. Check in your local directory for a shop that does it by you. Its more expensive than paint but you should be able to do all your parts for easily under $100.
Les Dit February 27th, 2005, 09:16 PM Interesting Brett. I've only used simple auto grey primer as a surface prep, and then the flat black. never had it come off. Maybe you got a bad can of Krylon ? I always clean the parts with acetone before paint. I've painted camera movements like this, and it seems to stick, even after getting oily.
How flat is powder coated flat black, when compared to the Krylon ?
-Les
Brett Erskine February 28th, 2005, 12:53 AM You can have powder coating done in multiple levels of non reflective black finish and various textures as well.
It's not so much that Krylon (or other flat black paints) wont stick, because they will...It's just that this kind of paint on smooth aluminum surfaces creates a thin shell-like layer that very much like the shell of an egg. Bump it and it will crack and large pieces will come off. If you rough up the surface of aluminum it will help a lot but still its not as good as powder coating. Think about all the other professionally made cameras and parts we have seen on the market. Do they paint the aluminum will black spray paint or do they have a unique texture to them...That texture is powder coating and there is a good reason why they have gone thru the extra effort and expense to use it.
Gev Babit March 1st, 2005, 01:07 AM Hey Brett thanks for the advive on the powder coating...
I have another question, do you have the Flange Focal Distance chart for
35mm lenses cause I found your post with the helpfull links and specifically this link "http://www.gregssandbox.com/gtech/filmfacts/flange.htm" that has the chart is dead.
Thanks,
Gev
Brett Erskine March 1st, 2005, 02:26 AM Oh damn. No I dont. And I didnt back up that page. Anyone else? You can figure it out by setting your lens to wide open and to the infinity focus mark. Point the lens at the far horizon and inch in your focusing screen. This will give you a pretty good idea what the flange focal length is. To find it exactly you need to now set the lens at the minimum focal distance thats marked on the lens. Set up a object at the same distance in front of the lens. This measurement should be from the object to the GG. Where the image appears to be perfectly in focus is your exact flange focal length for that lens mount. Measure carefully or make your adapter adjustable for back focus.
Les Dit March 1st, 2005, 02:33 AM I think with Nikon lenses, it's about 48 mm
Daves Spi March 1st, 2005, 03:45 AM Gev Babit: what did you use for holding the shafts ??? Some bearings, or some shaft sleeve or what ? I stick in this, do not know what to use for smooth movement of shafts in the plates...
Dogus Aslan March 1st, 2005, 11:53 AM internet is largeeeeeeeeeeeeeee:)
Camera mounts & registers:
http://www.a1.nl/phomepag/markerink/mounts.htm
Greg Boston March 1st, 2005, 12:29 PM FWIW, you can also buy do it yourself powder coating and aluminum anodizing kits from the internet. They aren't prohibitively expensive either. Do a google search and you'll find plenty of info.
Having seen your fine machining work Gev, I think these options would be well within your skill level.
-gb-
Gev Babit March 3rd, 2005, 03:38 AM Thanks Dogus & Greg!
Daves- I used ball bearings for the shafts and sandwiched the bearings between two plates. If you hammer in the bearings into the plate you might not be able to take them out or adjust them and they will get damaged, thats why I sandwiched them together between two plates. I am happy with this method, I can take the bearings out and adjust them whenever I wan't. The diameter of the bearing holes on the thin plates are 1mm less than the bearing, you tighten the three plates with small screws and nuts. Look at the pictures you can see how all the parts work. BTW I used two bearings for each shaft on the non-moving plate.
Gev
Daves Spi March 3rd, 2005, 03:47 AM <<<-- Originally posted by Gev Babit : Thanks Dogus & Greg!
Daves- I used ball bearings for the shafts and sandwiched the bearings between two plates. If you hammer in the bearings into the plate you might not be able to take them out or adjust them and they will get damaged, thats why I sandwiched them together between two plates. I am happy with this method, I can take the bearings out and adjust them whenever I wan't. The diameter of the bearing holes on the thin plates are 1mm less than the bearing, you tighten the three plates with small screws and nuts. Look at the pictures you can see how all the parts work. BTW I used two bearings for each shaft on the non-moving plate.
Gev -->>>
Thank you, I understand how it works, but I did not know that baerings can be so small... I'm building racing car, so I know just much bigger bearings :))) We are bulding SteadyCam, so we used the same technique in the arms... But had no idea about these small bearings... Going to build it next week... Thanks...
Les Dit March 3rd, 2005, 02:34 PM Gev,
Here is a tip for aligning and testing your device without a camera: Use a laser pointer and bounce it off the ground glass at an angle. Run the device, and view the spot the laser makes on a wall several feet away. The spot should not move around at all. If it is moving you will have image shake when you use it with a video camera.
Before you get too far into mounting a lens, etc, you might want to try this.
-Les
Sarena Valilis March 4th, 2005, 03:32 AM les,
although a good way to pick up misalignment, wouldnt that method exagerate the error that might not be as evident to a simple relay lens??
Les Dit March 4th, 2005, 05:05 AM Not really. Your eyes are very good at seeing image shake, and you really don't want any image shake at all. When the ground glass is moving, it should look motionless to the eye, unless you see the edges of the glass which are obviously seen to be moving. The shiny side of the GG should look like a static mirror. Trust me, I've had several attempts that 'looked' like it would work, but looked like crap with the video camera.
I finally got a version that works, which I plan on offering as a sub $500 kit, as I mentioned in another thread. I test with a HDV camera to make sure it will work on DV as well..
The laser test saves time, you don't end up wasting a bunch of time mounting up optics to a GG that is flapping around
-Les
<<<-- Originally posted by Sarena Valilis : les,
although a good way to pick up misalignment, wouldnt that method exagerate the error that might not be as evident to a simple relay lens?? -->>>
A.D.Wyatt Norton March 6th, 2005, 12:04 PM I finally got a version that works, which I plan on offering as a sub $500 kit, as I mentioned in another thread. I test with a HDV camera to make sure it will work on DV as well..
I don't want to cross-post, and you aren't having direct e-mail, so I'll just ask here that you make contact with me as someone truly interested in acquiring your kit when you're ready to make it available. I've seen in other threads that you're not too concerned with directly setting up for an XL. I wish you were, and I understand your disdain for SD resolution. HD is where it is all heading, I just wish the standards wars would conclude. I would be happy now if only I could have controlled DOF in shots, an artistic tool that I believe is the common desire drawing most of the people to all these Alternate Imaging Threads.
Les Dit March 9th, 2005, 01:48 AM So Gev, How did it look when the video was shot through the device ?
-Les
Gev Babit March 9th, 2005, 02:14 AM I did a really messy setup and taped it to a peice of wood. There was no image shake, it worked great....only problem is that the ground glass at 1500 grit is no good, resolution and projection wise. The mechinism works great the only thing is the optics that are not so good like the condensor and achromats. There are no hotspots or anything but it looks low res, maybe its my lens I dunno. But the mechnism works really well! I don't have any footage cause the ground glass has all these lines and spots, from touching it I guess, so I'm gonna get a new one and then see what happens!
Les Dit March 9th, 2005, 02:39 AM In my experience a fairly ordinary groundglass works pretty good. The motion of the groundglass hides any defects unless they are really big. Did the image look sharp without the condenser, just having the video camera shoot the ground glass directly? That would tell you if the condenser is blurring the image.
-Les
Gev Babit March 9th, 2005, 02:52 AM I didn't use a condensor cause it wasn't really doing anything, but the image is a little soft and looks low res. Maybe the condensor will make a difference but the one I have has alot of chromatic aberration, I dont want the yellow and blue fringe. I've noticed most of the adapters are soft, what does ps technik use to get it sharp like the camera is without the adapter? James' Micro35 is pretty sharp, sharper than most of the other ones on here.
Gev Babit March 10th, 2005, 03:17 AM Does anyone know if it is possible to control auto focus lenses? I have a nikon AF lens that I wan't to make a remote to control focus through the motor but I'm having trouble finding schematics or something that shows how the actual electronics work. I'm thinking of getting a cheap AF camera body and see if I can use the electronics to control the lens. A follow focus unit is
good but this method seems better. Any advice or tech info on this would be a great help. Thanks
Gev
Les Dit March 17th, 2005, 06:57 PM Any updates on your device? Did you run into any hotspot problems?
Gev Babit March 27th, 2005, 03:11 AM Hi, how is everyone?!!!
I have been working on it and solved the hotspot and optic problems by using a condensor. With the condensor I dont need to use a magnifying glass just the camera.
I have a question about optics though. Im trying to make a follow focus unit by moving the lens front and back instead of using the actual focus ring on the lens. Are there any optical problems by setting the lens to infinity and moving the lens forward and back. I will make sure that the lens doesnt go beyond the focusing distance that it is set by the manufacturer, i.e the closest my nikon can focus is 1.5 feet, I will not exceed that using this method. Instead of using the lens focus ring and custom gears for each type of lens ring, I will be able to move the lens forward/back with the mechanism and be able to make adapters for each kind of lens(i.e canon, nikon) to not exceed its focusing distance. Is there any optical issues?
Thanks,
Gev
Brett Erskine March 28th, 2005, 01:19 AM None that I could think of except the fact that the difference between infinity and minimum focus is often measured in a few mm when it comes to back focus. IF you decide to do this mechanism you can imagine the percision that would be needed in order for it to smoothly work properly. Also (as you noted) you would have to set the end marks for each different lens you use.
It's a interesting idea but I would recomend you not do it for simplicity sake. Perhaps you make the back focus adjustable for accurate focus purposes only. Just my two cents. Good luck.
Gev Babit March 29th, 2005, 11:57 PM Thanks Brett!
For me, at least, this seems easier cause each lens has different diameters, and the focus ring moves forward a little when you turn it. With this method I find it easier , and I can integrate it with the enclosure.
Here is a test model I built for testing and experimentation..
www.papalico.com/FollowFocus.mov
Dan Diaconu April 8th, 2005, 10:50 AM Gev,
I am sure you are aware of macro accessories for still photography that do just that. (it might save you some time of building it) One limitation (I think) would be "marking distances" (if need be) and speed in racking focus (if applies)
Otherwise, great job. You have focus with FF in one! Great! Keep it up.
Gev Babit April 10th, 2005, 03:14 AM Thanks Dan!
The macro stuff sounds interesting, where can I find those products from? Im looking for small sizes.
Thanks,
Gev
Dan Diaconu April 10th, 2005, 10:27 AM http://216.25.78.123/smallpics/olympus/104100.jpg
google for "macro rails" and once you know what to look for, check retailers on line or local second hand.
Leigh Wanstead April 11th, 2005, 03:24 PM Hi Gev,
Excellent work
Can you tell me what is the oscillate theory behind your device? I only know project image to the ground glass. I don't know how motor make your ground glass moving.
TIA
Leigh
Leo Mandy April 11th, 2005, 06:01 PM Gev,
What kind of condenser lens did you get and where did you get it? And if you don't mind me asking, how much did it cost?
Thanks
Radek Svoboda April 12th, 2005, 04:44 PM Gev,
You said originally that condenser had color fringing. Does fringing get better if you move condenser closer to screen?
The focusing with adapter is problematic because on telephoto you need to move lens a lot and on wide angle only very slightly.
Radek
Gev Babit April 13th, 2005, 02:34 AM Sorry for the late replys guys been busy.
Leigh: I put the link to the diagram from the oscillating thread that shows how it works. That should give you the basic idea of how it works, the difference between my adapter and that one is that I use two plates. I suggest you read the oscillating thread as it is explained, and there is alot more information in that thread that has helped me. Look at the pictures and footage of my mechanism in the beginning of this thread, you can learn about it there, I have explained how it works in detail. This is Rai Orz's Diagram from the oscillating thread and the thread itself.
http://de.geocities.com/raiorz/vibro_old/vibro1.jpg
http://www.dvinfo.net/conf/showthread.php?s=&threadid=27290
Mandy: I got a condensor from www.surplusshed.com.
In the menu choose "lensfinder" and put in this info. You dont need to put all the info just choose "PCX" lens and put minimun diameter to 48 and it should find it. Verify the results with the stock number.
Stock#: L8115
Type: PCX
Diameter: 48.0
Focal Length: 82
Coated: Y
$4.00
Mandy & Radek: The fringing problem does get better the closer you are to the ground glass. Although when you get too close, for me at least,1mm away, I got a barrel distortion like effect so you have to play with the distance from groud glass until there is no distortion or color fringing. Also experiment with the camera distance from condensor. The condensor works good enough that I didn't use an achromat (Im using the DVX100A).Unfortunatly I couldn't fully get rid of the chromatic aberration because as you move to the sides you see it more. The middle is fine but the sides are not so good. For me its not acceptable but maybe for you it will be. Its not that bad but its still there. I have to say that the condensor gave me the sharpest and brightest image from what I had tried before. The ccondensor works perfect except for the SLIGHT chromatic abberation, so for $4 you can try it and see....it can't hurt to try it and maybe it works for you. Later I got a focusing screen that I bought for 5 bucks that worked pretty good except there was a circle in the middle, so I decided to go with the Maxwell focusing screen and it works the best for me, I am very happy with it.
Here is the distance I used that worked the best for me with the Surplus Shed condensor.
25mm from Ground Glass. The flat side towards the Ground Glass. The condensor is supposed to be as close as possible but this gave me the best balanced image. The Camera was around 15mm away from the condensor. I should not that since the focal length of the condensor is 84mm the camera should be around 3 inches away. I used 15mm instead of 3 inches because I didn't want to use an achromat and make the adapter long. The achromat adds extra glass and distortion. These numbers worked for me, there was no vingeting, hotspot or distortion. The only problem, again, was the slight chromatic aberration. I used the DVX100A so you can get different results with different cameras. I suggest experimenting with the Condensor distance from Ground glass and the Camera distance from condensor to get the best picture and balance between hotspot, distortion, vingeting and chromatic aberration that works for YOU. Im not an optics expert, this is based on experimenting and my limited knowledge of optics.
Shawn Murphy April 13th, 2005, 09:31 AM Hey Gev,
Any samples/examples from your latest efforts?
thx.
Leigh Wanstead April 13th, 2005, 01:32 PM Hi Gev,
Thank you very much.
Regards
Leigh
Gev Babit April 16th, 2005, 01:05 AM No Problem!
I don't have any samples right now from the latest effort because It's not ready yet. I do have an image here from the condensor if anyone wants to see. I was using the ThorLabs 1500 grit ground glass, condensor and DVX100a. The lens is a nikon 50mm 1.4. The ground glass wasn't moving and it had a lot of dirt on it, as you can see.
www.papalico.com/Condensor.tif
-Gev
Daves Spi April 25th, 2005, 05:52 AM Hope I'll get good result too :) Your work is excellent...
http://web.datriware.com/gfx_photos/articles/p962.jpg
Hope the weight of DOF will absorb all vibrations :)
No Problem!
I don't have any samples right now from the latest effort because It's not ready yet. I do have an image here from the condensor if anyone wants to see. I was using the ThorLabs 1500 grit ground glass, condensor and DVX100a. The lens is a nikon 50mm 1.4. The ground glass wasn't moving and it had a lot of dirt on it, as you can see.
www.papalico.com/Condensor.tif
-Gev
Gev Babit April 28th, 2005, 01:57 AM Hey Daves, Thank you.
Bravo, that looks good!
If you are going to use a focusing screen try to keep the movment under 1mm. So if you offset the shaft by .5mm then you get 1mm of movment. Try to keep it around there or else you can get vibrations and the focusing screen will lose its effect if you move it too much. Congrats on making the mechanism, many people here are afraid to try it and don't think it can be done at home with these limited tool sets, but see you have. Looks Great, keep it up!
-Gev
Daves Spi April 28th, 2005, 02:07 AM Thanks,
my work is not so precise as your, I just wanted to try it and I made this in one day in hurry. I know if I would like to do it for second time, I will make more things much better. But unfortunately it does not work with any kind of fresnel lens, which i initialy plan it for. Once you get the lens move (even fresnel), you'll get perfect optical destabiliser. For GG works great.
http://web.datriware.com/gfx_photos/articles/p971.jpg
Hey Daves, Thank you.
Bravo, that looks good!
If you are going to use a focusing screen try to keep the movment under 1mm. So if you offset the shaft by .5mm then you get 1mm of movment. Try to keep it around there or else you can get vibrations and the focusing screen will lose its effect if you move it too much. Congrats on making the mechanism, many people here are afraid to try it and don't think it can be done at home with these limited tool sets, but see you have. Looks Great, keep it up!
-Gev
Les Dit April 28th, 2005, 05:32 AM Has anyone besides me and Dan posted a sample video of the orbital type adapter ? ( I posted 720P video a while back )
For me getting rid of the image shake/vibration took 3 attempts at a mechanism.
Now that I solved the stability, I still have to try the Maxwell screen, I just have been too busy with some other film projects to get to it.
For those of you with a device, and a memory of the old Wendy's ad:
"Where's the beef ? "
-Les
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