Mini35 Oscillating Ground Glass Idea

Les Dit · July 17th, 2004, 07:39 PM

You may recall from your school days that 3 points make a plane. So I recommend at least 3 support points. Otherwise it will flap around in funny ways.
After making mine with 3 , I would now use 4, because it allows more room for the glass. That needs 12 ball bearings and 4 shafts.

I posted pics of the one I made. ( see the DSC series in there )
http://home.earthlink.net/~lesd/hd/

Am I the only one to have done this?

My offer of providing pre machined kits still stands, $350 gets you all the stuff , without having to try to make it out of office supplies and kitchen junk ! ;)

-Les

Frank Ladner · July 18th, 2004, 12:01 AM

<<<-- Originally posted by Giroud Francois :
...the challenge is to find 4 really small ball bearing like you find in floppy drive or harddisk...-->>>

Giroud (and others): I have been looking around for bearings suitable for this project, as I am also wanting to build one of these. The hobby stores around here don't carry small enough bearings, and the suppliers I've found online seem to be for ordering in bulk. BUT, I do have access to a bunch of old floppy drives, hard drives, CD-ROM drives, etc that I can take apart. Would I find some of what I need in there, or is it built in a non-modular format to where the bearings couldn't be removed as a unit?

Thanks for you guys' help!

Justin Burris · July 18th, 2004, 12:29 AM

Giroud,

You are going with the vibrating version? Were you unsatisfied with the results of your static GG? It looked pretty good to me.

By the way, on your current static ground glass, how far can you stop down the lens before the grain starts to show?

Giroud Francois · July 18th, 2004, 02:23 AM

-yes i am happy with the static result but just for curiosity i want to try the moving one, because anyway if it is not ok , at least you can shut down the motor and get a static one.
-I think that 2 axis are ok due to the fact that all the stuff is vertical , wheith and distances are small, but you are right, 3 axis is safer and doesn't add much work.
for the parts like ball bearing, the problem ofgetting them from junk equipment is to find more than 2 or 3 parts with same specification. for those who make proto out of nothing like me, it can be ok if you do not plan to build more than one device and don't need for spare parts.
If we achive a good design, i think we could put our ressources together, each one providing what he can get easily and make a kit that contains all the hard to find parts.
list would be.
-8 small roller bearing +axis (30$ ?)
-2 aluminum tubes + sliding parts (20$)
- 2 macro lenses (2x5$)
- 50g of 1000 grit AO
..... add your items here.

Brett Erskine · July 18th, 2004, 02:54 AM

I was able to pick up bearings so small they wont even fit on the writing end of a pen. They are out there. I found mine at a r/c hobby store.

Les-
Im with you buddy. You, me and a few other people on this thread are making the same type of adapter. In fact Im the one that recomended changing the design to 4 shafts instead of 3 for the exact reason you just mentioned. I think people would be interested in the kits your willing to put together but make sure your not going to get yourself in trouble with P+S Technik. Since its only a part for the adapter you may not have any problems but check it out. If its a problem I know of some unique ways to move the GG that should get you around the patent.

Rai Orz · July 18th, 2004, 03:21 AM

Brett + Les,
how the the P+S work, you can see on this drawing. http://de.geocities.com/raiorz/vibro_old/vibro1.jpg. But don´t think you can go around the patent if you change the way you move it. The only statement in the P+S patent is that the use a moving GG. That means: They have a patent on all kinds of movings, rotation, slide, vibration and so on...

I had also made some different ways to move the GG. My company had checked the patent and we found a way to go around, but it is not in the way you move the GG.

PS: 3 point is the best, more or less and you have big problems..

Brett Erskine · July 18th, 2004, 04:23 AM

Why do you feel 4 points cause a problem?

Also is your design a no GG/front project system?

Giroud Francois · July 18th, 2004, 05:38 AM

my opinion is , if it works with 3 don't bother with 4.
For the kit, there is no problem as long as you sell it as a pack of general use parts. People can then do anything they want with after that. just do not put any explicit word or drawing into the description.
I like the design of the ver 2.1 but i think there is no point to move the motor out of the ring if we can put it on the same plate.
that way everyhting can fit in a closed tube.
should give something like this
http://www.giroud.com/minidv/vibro1.jpg
just replace one of the axis with the motor axis. you do not need the belt as the gg plate will act the same.
by viewing you drawing , i understand my idea is more complex to realize than your. Nice job.
as soon as i find the ball bearing i will start the stuff.

Rai Orz · July 18th, 2004, 06:54 AM

Brett, as Giround say: "...if it works with 3 don't bother with 4..." 4 can work, also 5, 6 or more, but why? It only cost power, work, $ and it can wedged.

Giround, well your idea will work. The only think is, you must found a small motor. The original motor can be on his place, because a prisma also need the space.

This way works also: Replace all 3 axis with motors and you don´t need a rubber belt. We found 3 identically constructed CD-ROM Motors have the power.

Les Dit · July 18th, 2004, 10:08 AM

The only reason I would use 4 shafts is to make it more compact.
On using the motor in place of the shaft, that can work, but remember that the little motors don't have ball bearings, and they may wear out fast because of the vibration motion.
I'm not worried about a patent issue, I am making a substrate shaker, not a GG shaker. It is also a parts set, you have to spend 15min putting the parts together. You can put some sandpaper in the middle and use it to file your finger nails, if you so desire!

Now, if you put GG in there, and sell it like that, you can get in trouble.

Static versions: I always warn people that still frames from these might look great, but the grain won't show on a still. Ask to see a slow panning shot of some out of focus scene. Look for the grain as a pattern that stays in the same place while the scene moves across the screen. It looks like a dirty lens cover. Mind you, I think it's possible to get good results with static methods, but my HD-10 JVC is harder to do this with. As the days of the web cam resolution cameras fade ( DV !) , moving GG will be a better look.

Frank Ladner · July 18th, 2004, 06:50 PM

I put together a 3D model of this device to show a family member (who's a machinist) so that he could get a good understanding of how the different parts of the device fit together. He is going to get it built for free / cheap. I just pay for materials.

http://www.frankladner.com/images/vibro_adapter_3D.gif

However, I am now thinking more towards the 4-pole version, since it would allow for a smaller unit.

Anyhow, I just thought I'd post it and maybe it would help some of the guys that are new to this project understand it better.

...now that I look back over the image, it may not be the best presentation...maybe a little confusing...but hopefully after comparisons are made from the various images/angles, it will fit together and make sense.

Thanks!

Giroud Francois · July 19th, 2004, 12:52 AM

that is a lot better.
But i still bo not understand why you add this plate in the middle with the ball bearings.
in theory just two plates, one static , one moving should be ok ?

Brett Erskine · July 19th, 2004, 01:33 AM

Excellent images! I dont want to speak for Franks design but your definately right in thinking that the concept will work with only two plates.

BTW Im also going with a 4 shaft system. Its not only smaller but its easier to build with less mass on the plate which will hold the GG.

The idea of having 3 or 4 motors instead of a pulley system introduces some possible problems you might want to consider. Each of thoughs motors will have to always be running at the EXACT speed for smooth/quiet motion and you just reduced your battery run time by 1/3 or 1/4th. Not to mention its also likely to be 3 to 4 times noiser. For these reasons Im making mine with a pulley drive.

Very nice work everyone. Were getting there.

P.S. Rai. I dont want you to give away your design if its going to turn into a money maker for you but could you at least give us a hint at the basic concept for the curious like myself? Being that I've been working on this project for over a year I've gone thru at least a dozen ways to make a mini35 like system work. My bet is on something similar to one of my design I posted awhile back. Its a adapter without any moving parts that is grainless (because there isnt any gg), flips the image right side up and works on the concept of front projection instead of rear projection. I decided against the design only because of light loss problems.

Rai Orz · July 19th, 2004, 04:30 AM

>The idea of having 3 or 4 motors instead of a pulley system introduces some possible problems you might want to consider. Each of thoughs motors will have to always be running at the EXACT speed for smooth/quiet motion and you just reduced your battery run time by 1/3 or 1/4th. Not to mention its also likely to be 3 to 4 times noiser.

No your wrong. We had build both, 3 axis with external pulley drive motor and 3 CD-ROM like motors instead the axis. and the last way was noiser and works with less power, because it work without a pulley. A CD-ROM motor is a 3-phase motor, it work with AC and you can connect every phase of the 3 (or more ) motors and with every puls all 3 motors move the exact same angle. But it will works also with 3 DC motors. The exact speed is given, because there is a little mecanical transmission over the moved platform, like the wheels on a old steam train are moved. Think on the pulley, it work also not exacty, but it work because there is also the mecanical transmission.

Brett, i know you design, but the light loss is the problem.

I know also a different design, maybe the best off all, but we can not >The idea of having 3 or 4 motors instead of a pulley system introduces some possible problems you might want to consider. Each of thoughs motors will have to always be running at the EXACT speed for smooth/quiet motion and you just reduced your battery run time by 1/3 or 1/4th. Not to mention its also likely to be 3 to 4 times noiser.

No your wrong. We had build both, 3 axis with external pulley drive motor and 3 CD-ROM like motors instead the axis. and the last way was noiser and works with less power, because it work without a pulley. A CD-ROM motor is a 3-phase motor, it work with AC and you can connect every phase of the 3 (or more ) motors and with every puls all 3 motors move the exact same angle. But it will works also with 3 DC motors. The exact speed is given, because there is a little mecanical transmission over the moved platform, like the wheels on a old steam train are moved. Think on the pulley, it work also not exacty, but it work because there is also the mecanical transmission.

Brett, i know you design, but the light loss is the problem.
I know also a different design, maybe the best of all, but we can not produce the necessary part. It is like a light-wave cable with 2 - 4 millions of threads, bundled on one side to the ccd format and at the other side to the 35mm format. It can mounted on the ccd and so it need no lenses.

We work since many years on different 35mm DOF solutions and other parts. (All for a movie production and it was before P+S make the adapter). I like to tell our last "secret", but this will cost my head. But i can tell some good and some bad ways. Maybe i can post some pictures of our older (but good working) parts. Also we can sell parts, that will be okay.

Frank Ladner · July 19th, 2004, 07:01 AM

Giroud: I thought at first about just removing the bottom plate. But then I thought about the pulleys where the belt is attached underneath. I figured that there would be tension from the belt squeezing the poles together and that they would need support. I guess this depends on how much slack there would be in the bearings. Likely none but would it wear things down faster not having a bottom support plate? (But then again, with the top plate for support, they couldn't be 'squeezed' in too much, eh?)

However, removing the MIDDLE plate, as you suggest, might work. I guess the pulleys would then be placed in the middle. That would simplify it and make it cheaper. Hrrrmm..... This sounds like something to try.

Thanks for the feedback, guys!

July 18th, 2004, 12:01 AM	#92
Frank Ladner Major Player Join Date: Aug 2003 Location: Poplarville, MS Posts: 453	Bearings from disk drives? <<<-- Originally posted by Giroud Francois : ...the challenge is to find 4 really small ball bearing like you find in floppy drive or harddisk...-->>> Giroud (and others): I have been looking around for bearings suitable for this project, as I am also wanting to build one of these. The hobby stores around here don't carry small enough bearings, and the suppliers I've found online seem to be for ordering in bulk. BUT, I do have access to a bunch of old floppy drives, hard drives, CD-ROM drives, etc that I can take apart. Would I find some of what I need in there, or is it built in a non-modular format to where the bearings couldn't be removed as a unit? Thanks for you guys' help!

July 18th, 2004, 10:08 AM	#100
Les Dit Major Player Join Date: Oct 2003 Location: Southern Cal-ee-for-Ni-ya Posts: 608	little motors, static screen frame grab trickery The only reason I would use 4 shafts is to make it more compact. On using the motor in place of the shaft, that can work, but remember that the little motors don't have ball bearings, and they may wear out fast because of the vibration motion. I'm not worried about a patent issue, I am making a substrate shaker, not a GG shaker. It is also a parts set, you have to spend 15min putting the parts together. You can put some sandpaper in the middle and use it to file your finger nails, if you so desire! Now, if you put GG in there, and sell it like that, you can get in trouble. Static versions: I always warn people that still frames from these might look great, but the grain won't show on a still. Ask to see a slow panning shot of some out of focus scene. Look for the grain as a pattern that stays in the same place while the scene moves across the screen. It looks like a dirty lens cover. Mind you, I think it's possible to get good results with static methods, but my HD-10 JVC is harder to do this with. As the days of the web cam resolution cameras fade ( DV !) , moving GG will be a better look.

July 17th, 2004, 07:39 PM	#91
Les Dit Major Player Join Date: Oct 2003 Location: Southern Cal-ee-for-Ni-ya Posts: 608	You may recall from your school days that 3 points make a plane. So I recommend at least 3 support points. Otherwise it will flap around in funny ways. After making mine with 3 , I would now use 4, because it allows more room for the glass. That needs 12 ball bearings and 4 shafts. I posted pics of the one I made. ( see the DSC series in there ) http://home.earthlink.net/~lesd/hd/ Am I the only one to have done this? My offer of providing pre machined kits still stands, $350 gets you all the stuff , without having to try to make it out of office supplies and kitchen junk ! ;) -Les

July 18th, 2004, 12:29 AM	#93
Justin Burris Regular Crew Join Date: Jan 2004 Location: Olympia, WA Posts: 54	Giroud, You are going with the vibrating version? Were you unsatisfied with the results of your static GG? It looked pretty good to me. By the way, on your current static ground glass, how far can you stop down the lens before the grain starts to show?

July 18th, 2004, 02:23 AM	#94
Giroud Francois Inner Circle Join Date: Feb 2004 Location: switzerland Posts: 2,133	-yes i am happy with the static result but just for curiosity i want to try the moving one, because anyway if it is not ok , at least you can shut down the motor and get a static one. -I think that 2 axis are ok due to the fact that all the stuff is vertical , wheith and distances are small, but you are right, 3 axis is safer and doesn't add much work. for the parts like ball bearing, the problem ofgetting them from junk equipment is to find more than 2 or 3 parts with same specification. for those who make proto out of nothing like me, it can be ok if you do not plan to build more than one device and don't need for spare parts. If we achive a good design, i think we could put our ressources together, each one providing what he can get easily and make a kit that contains all the hard to find parts. list would be. -8 small roller bearing +axis (30$ ?) -2 aluminum tubes + sliding parts (20$) - 2 macro lenses (2x5$) - 50g of 1000 grit AO ..... add your items here.

July 18th, 2004, 02:54 AM	#95
Brett Erskine Major Player Join Date: Dec 2003 Location: Anaheim, CA Posts: 445	I was able to pick up bearings so small they wont even fit on the writing end of a pen. They are out there. I found mine at a r/c hobby store. Les- Im with you buddy. You, me and a few other people on this thread are making the same type of adapter. In fact Im the one that recomended changing the design to 4 shafts instead of 3 for the exact reason you just mentioned. I think people would be interested in the kits your willing to put together but make sure your not going to get yourself in trouble with P+S Technik. Since its only a part for the adapter you may not have any problems but check it out. If its a problem I know of some unique ways to move the GG that should get you around the patent.

July 18th, 2004, 03:21 AM	#96
Rai Orz Regular Crew Join Date: Jun 2004 Location: Germany Posts: 136	Brett + Les, how the the P+S work, you can see on this drawing. http://de.geocities.com/raiorz/vibro_old/vibro1.jpg. But don´t think you can go around the patent if you change the way you move it. The only statement in the P+S patent is that the use a moving GG. That means: They have a patent on all kinds of movings, rotation, slide, vibration and so on... I had also made some different ways to move the GG. My company had checked the patent and we found a way to go around, but it is not in the way you move the GG. PS: 3 point is the best, more or less and you have big problems..

July 18th, 2004, 04:23 AM	#97
Brett Erskine Major Player Join Date: Dec 2003 Location: Anaheim, CA Posts: 445	Why do you feel 4 points cause a problem? Also is your design a no GG/front project system?

July 18th, 2004, 05:38 AM	#98
Giroud Francois Inner Circle Join Date: Feb 2004 Location: switzerland Posts: 2,133	my opinion is , if it works with 3 don't bother with 4. For the kit, there is no problem as long as you sell it as a pack of general use parts. People can then do anything they want with after that. just do not put any explicit word or drawing into the description. I like the design of the ver 2.1 but i think there is no point to move the motor out of the ring if we can put it on the same plate. that way everyhting can fit in a closed tube. should give something like this http://www.giroud.com/minidv/vibro1.jpg just replace one of the axis with the motor axis. you do not need the belt as the gg plate will act the same. by viewing you drawing , i understand my idea is more complex to realize than your. Nice job. as soon as i find the ball bearing i will start the stuff.

July 18th, 2004, 06:54 AM	#99
Rai Orz Regular Crew Join Date: Jun 2004 Location: Germany Posts: 136	Brett, as Giround say: "...if it works with 3 don't bother with 4..." 4 can work, also 5, 6 or more, but why? It only cost power, work, $ and it can wedged. Giround, well your idea will work. The only think is, you must found a small motor. The original motor can be on his place, because a prisma also need the space. This way works also: Replace all 3 axis with motors and you don´t need a rubber belt. We found 3 identically constructed CD-ROM Motors have the power.

July 18th, 2004, 06:50 PM	#101
Frank Ladner Major Player Join Date: Aug 2003 Location: Poplarville, MS Posts: 453	I put together a 3D model of this device to show a family member (who's a machinist) so that he could get a good understanding of how the different parts of the device fit together. He is going to get it built for free / cheap. I just pay for materials. http://www.frankladner.com/images/vibro_adapter_3D.gif However, I am now thinking more towards the 4-pole version, since it would allow for a smaller unit. Anyhow, I just thought I'd post it and maybe it would help some of the guys that are new to this project understand it better. ...now that I look back over the image, it may not be the best presentation...maybe a little confusing...but hopefully after comparisons are made from the various images/angles, it will fit together and make sense. Thanks!

July 19th, 2004, 12:52 AM	#102
Giroud Francois Inner Circle Join Date: Feb 2004 Location: switzerland Posts: 2,133	that is a lot better. But i still bo not understand why you add this plate in the middle with the ball bearings. in theory just two plates, one static , one moving should be ok ?

July 19th, 2004, 01:33 AM	#103
Brett Erskine Major Player Join Date: Dec 2003 Location: Anaheim, CA Posts: 445	Excellent images! I dont want to speak for Franks design but your definately right in thinking that the concept will work with only two plates. BTW Im also going with a 4 shaft system. Its not only smaller but its easier to build with less mass on the plate which will hold the GG. The idea of having 3 or 4 motors instead of a pulley system introduces some possible problems you might want to consider. Each of thoughs motors will have to always be running at the EXACT speed for smooth/quiet motion and you just reduced your battery run time by 1/3 or 1/4th. Not to mention its also likely to be 3 to 4 times noiser. For these reasons Im making mine with a pulley drive. Very nice work everyone. Were getting there. P.S. Rai. I dont want you to give away your design if its going to turn into a money maker for you but could you at least give us a hint at the basic concept for the curious like myself? Being that I've been working on this project for over a year I've gone thru at least a dozen ways to make a mini35 like system work. My bet is on something similar to one of my design I posted awhile back. Its a adapter without any moving parts that is grainless (because there isnt any gg), flips the image right side up and works on the concept of front projection instead of rear projection. I decided against the design only because of light loss problems.

July 19th, 2004, 04:30 AM	#104
Rai Orz Regular Crew Join Date: Jun 2004 Location: Germany Posts: 136	>The idea of having 3 or 4 motors instead of a pulley system introduces some possible problems you might want to consider. Each of thoughs motors will have to always be running at the EXACT speed for smooth/quiet motion and you just reduced your battery run time by 1/3 or 1/4th. Not to mention its also likely to be 3 to 4 times noiser. No your wrong. We had build both, 3 axis with external pulley drive motor and 3 CD-ROM like motors instead the axis. and the last way was noiser and works with less power, because it work without a pulley. A CD-ROM motor is a 3-phase motor, it work with AC and you can connect every phase of the 3 (or more ) motors and with every puls all 3 motors move the exact same angle. But it will works also with 3 DC motors. The exact speed is given, because there is a little mecanical transmission over the moved platform, like the wheels on a old steam train are moved. Think on the pulley, it work also not exacty, but it work because there is also the mecanical transmission. Brett, i know you design, but the light loss is the problem. I know also a different design, maybe the best off all, but we can not >The idea of having 3 or 4 motors instead of a pulley system introduces some possible problems you might want to consider. Each of thoughs motors will have to always be running at the EXACT speed for smooth/quiet motion and you just reduced your battery run time by 1/3 or 1/4th. Not to mention its also likely to be 3 to 4 times noiser. No your wrong. We had build both, 3 axis with external pulley drive motor and 3 CD-ROM like motors instead the axis. and the last way was noiser and works with less power, because it work without a pulley. A CD-ROM motor is a 3-phase motor, it work with AC and you can connect every phase of the 3 (or more ) motors and with every puls all 3 motors move the exact same angle. But it will works also with 3 DC motors. The exact speed is given, because there is a little mecanical transmission over the moved platform, like the wheels on a old steam train are moved. Think on the pulley, it work also not exacty, but it work because there is also the mecanical transmission. Brett, i know you design, but the light loss is the problem. I know also a different design, maybe the best of all, but we can not produce the necessary part. It is like a light-wave cable with 2 - 4 millions of threads, bundled on one side to the ccd format and at the other side to the 35mm format. It can mounted on the ccd and so it need no lenses. We work since many years on different 35mm DOF solutions and other parts. (All for a movie production and it was before P+S make the adapter). I like to tell our last "secret", but this will cost my head. But i can tell some good and some bad ways. Maybe i can post some pictures of our older (but good working) parts. Also we can sell parts, that will be okay.

July 19th, 2004, 07:01 AM	#105
Frank Ladner Major Player Join Date: Aug 2003 Location: Poplarville, MS Posts: 453	Giroud: I thought at first about just removing the bottom plate. But then I thought about the pulleys where the belt is attached underneath. I figured that there would be tension from the belt squeezing the poles together and that they would need support. I guess this depends on how much slack there would be in the bearings. Likely none but would it wear things down faster not having a bottom support plate? (But then again, with the top plate for support, they couldn't be 'squeezed' in too much, eh?) However, removing the MIDDLE plate, as you suggest, might work. I guess the pulleys would then be placed in the middle. That would simplify it and make it cheaper. Hrrrmm..... This sounds like something to try. Thanks for the feedback, guys!