View Full Version : Oscillation Idea


Aaron Shaw
January 20th, 2005, 10:26 AM
Hey guys,

Something just occured to me last night when I was half asleep (seems I'm most creative that way...). I was pondering decent ways to change some of the current static designs into oscillating adapters without having to loose the optics tube (very useful thing really).

So while pondering various ways that this could be achieved it hit me: why use a mechanical device at all? Couldn't we build some sort of magnetic oscillator? If done correctly it would require no external power source. The only question in my mind is whether a large enough vibration could be introduced from conflicting magnetic fields to effectively blur the grain at higher shutter speeds.

What do you guys think? Am I just going crazy?

Cosmin Rotaru
January 20th, 2005, 11:42 AM
Plain magnets? No external power source? No ELECTROmagnets?
plain magnets will come into equilibrium no matter how you place them, unless you plan to shake the camcorder... :)

Aaron Shaw
January 20th, 2005, 11:52 AM
Electromagnets could be used of course :)

I'm not entirely certain it would. So long as there is a confliction of magentic fields these things will keep moving. Same as those annoying little table top things that constantly move due to magnets (hard to describe..).

James Hurd
January 20th, 2005, 11:56 AM
Vibration.

Aaron Shaw
January 20th, 2005, 12:02 PM
Vibration?

As in you think there will be too much?

James Hurd
January 20th, 2005, 12:47 PM
Yes sir. moving anything that's not properly balanced will create vibration. Through my tests, having something ~1mm off would create too much vibration..

Aaron Shaw
January 20th, 2005, 12:54 PM
Yes that is an excellent point. Anyway, it's something I may play around with just to see if it's possible.

If this were to be done without electromagnets someone would have to come up with a very creative means of keeping the glass in continual motion (as we can't shift the poles).

While we're at it though, anyone else have a good idea for how to mod these static adapters (using filter rings or more preferably the optosigma optics tube) to oscillate?

Cosmin Rotaru
January 21st, 2005, 02:07 AM
Aaron, "perpetum mobile" does not exist. The "annoying little table top things that constantly move due to magnets" are pseudo "perpetum mobile" (have a battery inside). Or they just stop after a while.

Aaron Shaw
January 21st, 2005, 11:10 AM
Oh quite right. I'm certainly not a believer in perpetual motion. I just think that the motion will last long enough for my purposes. I'll let you guys know if anything works decently.

Brett Erskine
January 22nd, 2005, 07:36 PM
I'm not sure how you want to put this together but dont forget how important its is that the GG doesnt shift even a single mm towards or away from its relationship to the 35mm lens other wise you'll see the focus shift on you as well. And your camera isnt going to be perfectly still when your using it so ask yourself what bumping around will do to this issue. I would think this would be hard to make work but then again I'm not seeing exactly how you plan on making it mechanically. Like the idea though. Could be completely silent.

Aaron Shaw
January 22nd, 2005, 08:53 PM
Yeah that's one of my main worries. I think this could possibly be solved by making sure the GG was tight in optics tube. Not so tight that it can't rotate but tight enough it won't shift back and forth.

I have a bunch of different drawings I made up of layouts. Many bad, some good. Brainstorming really. I think one possible solution would be to do something like this:

http://www.weet.us/magnet.GIF

If you laid this out right the magnet on the GG would possibly get trapped between each field of the other magnets and vibrate back and forth. I have no clue if it would work though. Ideas or comments?

[NOTE: I just made this in PAINT so it's crappy looking]

EDIT: back and forth as in back and forth between the two exterior magnets giving a sea type motion to the entire glass.

Dan Diaconu
January 23rd, 2005, 11:20 AM
Back and forth would give you two end points of the grain showing two spots (ends of race) but......
could THIS be what you are after?: (nice job Obin!)

http://dandiaconu.com/gallery/albums/35mm-lens-adapter-latest-vesion-on-Jan-22-2005/noise_level.wmv

and this?

http://dandiaconu.com/gallery/albums/35mm-lens-adapter-latest-vesion-on-Jan-22-2005/planeity.wmv

and in the end make it look like this?:

http://dandiaconu.com/gallery/35mm-lens-adapter-latest-vesion-on-Jan-22-2005/IMGA0125_1
http://dandiaconu.com/gallery/35mm-lens-adapter-latest-vesion-on-Jan-22-2005/IMGA0130_1
http://dandiaconu.com/gallery/35mm-lens-adapter-latest-vesion-on-Jan-22-2005/IMGA0137

From an "idea".... to have a working model in your hands is a loooong way. The only way to see how long, is to try it.

Aaron Shaw
January 23rd, 2005, 11:31 AM
Not entirely sure what you are saying Dan. I'm probably just really tired though.

I certainly realize that an idea to fully working piece is a long process. I never intended to claim otherwise! I was just proposing an idea to the board and all the comments have been helpful.

Brett Erskine
January 23rd, 2005, 12:14 PM
Shawn-
From the picture it looks like you just a few magnets shy of how a motor works.

Dan-
Simply put it looks like your done. FOV, brightness, noise level, etc look right on the money. So when are you going to sell them? Actually I was wondering about one minor thing though. That back clear dust productive filter - isnt it too close? What I mean is having it so close to the plane of the GG seems like you have to have it perfectly clean otherwise any dust, dirt or hair will become visable although it will be very much out of focus. Have you found that to be true?

Aaron Shaw
January 23rd, 2005, 12:18 PM
Yep, quite right Brett. A motor requires that you switch back and forth between + and - on each side (to keep the middle spinning around). This would only wobble. Maybe enough maybe not. Worth an experiment though!

Dan, I'm also interested in when you will sell these. I'm also quite interested in the internal setup. Not necessarily the vibration mechanism but the optics. I'm trying to design an adapter with maximum light efficiency and lack of distortion but if yours already achieves that (need to see the setup to see if it could be improved) then I'll just buy one of yours!

James Hurd
January 23rd, 2005, 12:27 PM
Dan,
How's the vibration? Could you shoot some video of the device setting on its end with the power on? What are you doing for a macro?

Thanks Dan!

Dan Diaconu
January 23rd, 2005, 12:46 PM
I will shoot and post more footage/stills today.

James Hurd
January 23rd, 2005, 01:27 PM
Thanks Dan!

Great work by the way!


james

Dan Diaconu
January 23rd, 2005, 08:27 PM
Fail? Pass?

http://dandiaconu.com/gallery/albums/35mm-lens-adapter-latest-vesion-on-Jan-22-2005/GELO_TEST.wmv


Did not get the chance to reply earlier. Brett, you are right about back filter (same with the front) but if they are not there, how can this be water proof? Inside is clean (on me) ouside is on you. Once I will finish al tests, I will start taking orders. But first, one must know what is there, right?

James Hurd
January 23rd, 2005, 09:09 PM
Dan,
You are too funny. Looks like the LED is working well!

What kind of price are you looking at? What about the macro?

Brett Erskine
January 24th, 2005, 12:35 PM
Dan-
About the filters> Yeah I had the same problem. The solution is just to extend the distance between the GG and the back filter. Try just nother inch or so. This will put any dust that is sure to get on the filter so out of focus that it will never be seen. Makes the adapter worry free otherwise you have to be absolutely perfect every time you remove it otherwise you could be in for a surprise when viewing it after the fact. Unfortunately this also means that your adapter would be about a inch longer and I can tell you were very interested in keeping this as compact as possible. The P+S Technik doesnt have this problem because it creates this needed gap between the outter glass and the GG by the crisscross light path the image takes in the prism. Anyways something easy to fix and consider.

Dan Diaconu
January 24th, 2005, 01:08 PM
Thanks Brett,
The back cover filter is just a....cover. One could remove it and replace it with a spacer (or take the filter out of the mount) but the waterproof is gone.
Dust has all ways been an issue in this field. But were there is a problem, there is room for solutions.
I had the same thing made with a mirror and a prism attached. I would not do it again. Size, weight, cost, etc. Besides, I had a spec of dust just on the surface of the prism (@0.4mm from the GG! what to do about it other than blow it with compressed air? I did not have in that design the filter behind SLR mount that I have now, that is true.
Anyway, why prism and mirror when you can flip it in post? (and mount two switches on the side of the monitor?)
I am always for new. I see this simple way to achieve the purpose with less trouble.

Filip Kovcin
January 25th, 2005, 07:16 AM
really funny with that jelly. in poland we call it GALARETKA. so your device passed great GALARETKA test. exellent!

i understand, that motor was working during the test, not just the led?

impresive.


filip


p.s.

dan,

can you show us how noisy s your device when close to mics?

thanks.

Dan Diaconu
January 25th, 2005, 10:52 AM
http://dandiaconu.com/gallery/albums/35mm-lens-adapter-latest-vesion-on-Jan-22-2005/noise_level.wmv

Filip Kovcin
January 25th, 2005, 11:33 AM
thank you Dan.