View Full Version : Film Back for HVX - Matchmoving
Film_is_dead
08-03-2007, 11:38 AM
I'm trying to do some matchmoving ang I can't find the film back dimentions. I think they are the same as the CMOS chip dimensions?
Thank you for any help! ;-)
The best way is to phone to Panasonic's tech support line. But here is my own calculation: HVX200 1/3" CCD( it refers to the diagonal measurement of the 16:9 native sensor)
1/3" CCD that means 0.333 inches and equal 8.467 mm
Normally, when they say 1/3" CCD actually means 2/3 of it
So 8.467mm mutiply by 2/3 = 6 mm ( we got the diagonal )
Next, with a basic Hypotenuse Z power of 2 = X power of 2 multiply Y power of 2
16/9 = x/y
y =9x/16
x = 16y/9
let replace y by 9x/16
6 x 6 = x power of 2 multiply (9x/16) power of 2
x = 5.223 mm
y = 5.223 mutiply by 9/16
y = 2.938 mm
To prove it 5.223 / 2.938 is 1.777 which is 16:9 aspect ratio
To answer your question x = 5.223 mm, y = 2.938 mm ( close enough )
CerpinTaxt
08-06-2007, 11:26 AM
Hi, I'm doing some matchmoving myself. I used the CCD- sizes from this URL
http://www.dpreview.com/learn/?/Glossary/Camera_System/sensor_sizes_01.htm
1/3" --> 4.8mm x 3.6mm 4:3
6.4mm x 3.6mm 16:9
works fine for me so far.
I got another problem. I don't have the focal length but only the z-values like Z21, Z67 etc. Is there a table where I can get these values in mm?
I read that you can switch the display from z to mm-values. Maybe someone who has a HVX200 could give me the focal length in mm for the following z-values?
z00 (probably 4.2mm), z01, z06, z08, z09, z10, z16, z19, z21, z25, z32, z41, z46, z52, z53, z54, z55, z60, z67
Thanks in advance
someday
08-09-2007, 04:08 AM
Film_is_dead, i like your nick...
In this world goods are murdered.
I looked at 300 trailers yesterday. Almost all had were made witout film. They looked like youtube with less compression.
I really miss the poesy of 35mm and 70mm film.
Look at "Lost in translation" and how a 35mm Arri and Aaton footage can look.
We will have to wait for 20 years to get the film poesy with digital technology.
It's the same paradigm shift that happened in the audio domain when studios started to produce digitally.
The sound was crappy and we needed 20 years to get good sounding digital music.
BTW i wait going IMAX cinemas, the only true film survivor.
.
Film_is_dead
10-04-2007, 08:03 AM
Thank you all for your excellent replies and help.
I use an HVX200 with a super fisheye from Century Optics (now a Schneider company). It has very good quality and I get an angle equivalent to 9.75 mm in 35mm format or 1.35 in HD format. I get this by multiplying 4mm (widest setting for HVX) by 0.3 (adjustment coefficient for the fiisheye).
I get barrel distortion and because it's Very specific I found out that no package can undistort it for 3D object addition in 3dsmax I use. So I created a Max file that I project the previously rendered 3D on a plane distorted to match the barrel backround for the HVX and works ok.
The problem now is that due to the nodal pan shot I see that the 3D objects "rotate" in the scene.. When it's in the center area it rotates less but in the corners ir wants to rotate more and slide more (M.Jackson moonwalking style).. Anyone had this problem before?? I am sure it happens in any lens but it get very extreme with a fisheye. For now I have to animate the 3D objects individualy and it's time consuming with 70% good results.
thank you all for your replies.