Mini 35 Competing Unit for a Lot Less $ - Page 2 at DVinfo.net

Go Back   DV Info Net > Special Interest Areas > Techniques for Independent Production

Techniques for Independent Production
The challenges of creating Digital Cinema and other narrative forms.


Reply
 
Thread Tools Search this Thread
Old June 23rd, 2003, 08:23 PM   #16
Permanently Banned
 
Join Date: Mar 2003
Location: Los Angeles, California
Posts: 265
Hi guys, I'm back from my trip. There is no vignetting. You use the GG in the film plane. There is no vignetting on film either. You vibrate the glass to the sides only. The image will not be perfect; you can claim it is a film look -- some of the grain. The vaibrations need very high frequency so the video frame sees always more than one spot. But we tried it and piezo drive does not work.
Joseph George is offline   Reply With Quote
Old June 24th, 2003, 03:43 AM   #17
Major Player
 
Join Date: Feb 2003
Location: Romania, Timisoara
Posts: 453
Whell, in film there is no vigneting but you're not interested in the light that passes throu the film...
Could you give me some info on the gg you use? Maybe the manufacturer? Thank you!
Cosmin Rotaru is offline   Reply With Quote
Old June 24th, 2003, 10:12 PM   #18
New Boot
 
Join Date: May 2003
Posts: 15
Hey joseph,

Why a piezoelectric drive as opposed to a vibration motor? What would you consider a high frequency (rpm)?
Jaime Roman is offline   Reply With Quote
Old June 25th, 2003, 06:39 AM   #19
Major Player
 
Join Date: Feb 2003
Location: Romania, Timisoara
Posts: 453
Hi all,
This is my own attempt, my little experiment on this mini35 homemade stuff...

This is the 50mm lens I use. For this test the iris was wide open at 1.8. (quite a fast lens - very narrow DOF at this opening)
http://www.dvinfo.net/media/cosmin/50mm%20lens.jpg

This is the fresnell I use. Is a book sign...
http://www.dvinfo.net/media/cosmin/fresnell.jpg

The little GG. I cut it from a fake CD. The kind of unusable look alike CDs that you find in bulk CD boxes. They're at the bottom and on top of the bulk, for protection.
http://www.dvinfo.net/media/cosmin/GG.jpg

The GG and fresnell makes a sandwich. There's about 2mm space between the two. If there's no space between them, the fresnell's rings becomes visible.

I use an old electric razor as a means for vibrating the GG/fresnell sandwich!
http://www.dvinfo.net/media/cosmin/razor.jpg

Here are all parts in an improvised homemade mini35 adapter. I'll have to do more experiments until I decide if it worth doing something stable and usable.
http://www.dvinfo.net/media/cosmin/setup.jpg

Now for the tests:

This is a pic using the camcorder's lens alone (canon XM2 - European PAL version)
http://www.dvinfo.net/media/cosmin/normal.jpg

Here's a pic using the homemade adapter with the GG not vibrating. Very grainy. I think I need a better GG.
http://www.dvinfo.net/media/cosmin/grainy.jpg

This is a pic with the homemade adapter. The GG is vibrating. I also modified a little the color curves.
http://www.dvinfo.net/media/cosmin/v...d%20curves.jpg

Here you can see a little demo clip (you need WMP9) that starts with a grainy look and than the GG starts vibrating and the grain almost disappears. I modified the color curves also, for the part were the GG vibrates. :)
http://www.dvinfo.net/media/cosmin/cosmin.wmv

Din anyone tried something else?
Cosmin Rotaru is offline   Reply With Quote
Old June 25th, 2003, 06:45 AM   #20
Obstreperous Rex
 
Join Date: Jan 2001
Location: San Marcos, TX
Posts: 26,900
Images: 513
Cosmin, these aren't loading for me. If you can send them to me by email, I'll be happy to put them on the DV Info server for easier access.
__________________
CH

Search DV Info Net | DV Info Net Sponsors | A Decade (+5) of DVi | ...Tuesday is Soylent Green Day!
Chris Hurd is offline   Reply With Quote
Old June 25th, 2003, 06:51 AM   #21
Major Player
 
Join Date: Feb 2003
Location: Romania, Timisoara
Posts: 453
I don't know... I can open the pics but the video is totaly unaccesible...
I'll send you an e-mail Chris, if you can help me with this.
Thanks!
Cosmin Rotaru is offline   Reply With Quote
Old June 25th, 2003, 07:02 AM   #22
Major Player
 
Join Date: Feb 2003
Location: Romania, Timisoara
Posts: 453
I've sent you the pics and the clip.

Cosmin
Cosmin Rotaru is offline   Reply With Quote
Old June 25th, 2003, 07:38 AM   #23
Obstreperous Rex
 
Join Date: Jan 2001
Location: San Marcos, TX
Posts: 26,900
Images: 513
See http://www.dvinfo.net/media/cosmin/ -- this should provide a clickable directory listing of these images and the video clip. It'll have to do until I can put a page together; I'm leaving momentarily for the L.A. Entertainment Technology World trade show.
__________________
CH

Search DV Info Net | DV Info Net Sponsors | A Decade (+5) of DVi | ...Tuesday is Soylent Green Day!
Chris Hurd is offline   Reply With Quote
Old June 25th, 2003, 08:35 AM   #24
Major Player
 
Join Date: Feb 2003
Location: Romania, Timisoara
Posts: 453
Have fun there, Chris!
And thanks!


I have updated the links on the original post. I hope now they're working!


Cosmin
Cosmin Rotaru is offline   Reply With Quote
Old June 25th, 2003, 10:07 AM   #25
Permanently Banned
 
Join Date: Mar 2003
Location: Los Angeles, California
Posts: 265
Edmund Scientific sells ground glass. The piezo elements would make it a nice reliable design. The image stays o the GG. It does not go through the GG. Frequency? I would say as high as possible -- couple hundred Hz and up.
Joseph George is offline   Reply With Quote
Old June 25th, 2003, 10:33 AM   #26
Major Player
 
Join Date: Aug 2002
Location: Melbourne, Australia
Posts: 730
Not exactly quiet heh heh, looks cool though.

Zac
Zac Stein is offline   Reply With Quote
Old June 25th, 2003, 10:35 AM   #27
Major Player
 
Join Date: Feb 2003
Location: Romania, Timisoara
Posts: 453
Hi Joseph,
have you seen my "setup"? You're probably doing it in some other way... In my setup the light has to go thru the GG. Some GGs would make smaller vigneting at the expense of loosing much of the light. If the GG is not that dense (it is more clear) it would transmit more of the light but with more vigneting. The fresnell always helps in the setup I'm testing...
Cosmin Rotaru is offline   Reply With Quote
Old June 25th, 2003, 10:41 AM   #28
Major Player
 
Join Date: Feb 2003
Location: Romania, Timisoara
Posts: 453
Well, it is an electric razor, Zac! :)
My wife didn't like the noise either! (It was like 2 o'clock in the night when I finally pushed the button!) I think it vibrates at 50Hz. This is what we have here: 220V at 50Hz. So the ancient razor I think it goes 50 cycles/second!
I'll do more testing. I'm not going to use the shaver in a final setup, though. :)

(is it "razor" or "shaver"? - English is not my native language...)
Cosmin Rotaru is offline   Reply With Quote
Old June 25th, 2003, 10:45 AM   #29
Major Player
 
Join Date: Aug 2002
Location: Melbourne, Australia
Posts: 730
They are called, electronic razors/shavers here... but I don't speak 'yank' so I am not sure what they call it. We already had quite a large discussion about flip flops.

I would love to see a schematic of this thing... i have a lot of parts sitting around, and am meeting with an engineer first thing next week, would be great to knock this thing together.

Zac
Zac Stein is offline   Reply With Quote
Old June 25th, 2003, 11:13 AM   #30
Major Player
 
Join Date: Feb 2003
Location: Romania, Timisoara
Posts: 453
Hey, I thought the pic would be enough to see what I did!
http://www.dvinfo.net/media/cosmin/setup.jpg
Just ask what is not clear from the pic, ok? I'll be happy to answer your questions!

O! The lens I'm holding goes on the camcorders lens. As close as posible. So I could zoom al the way in to the GG and still focus. If I just bring the camcorder close to the GG (in macro), I'm to close to the fresnell and out of its focal point. Way out! So that's translated into a BIG vigneting problem!
Cosmin Rotaru is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Special Interest Areas > Techniques for Independent Production

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 05:19 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network