WS out of focus, may be macro setting at DVinfo.net

Go Back   DV Info Net > JVC ProHD & MPEG2 Camera Systems > JVC GY-HD Series Camera Systems

JVC GY-HD Series Camera Systems
GY-HD 100 & 200 series ProHD HDV camcorders & decks.


Reply
 
Thread Tools Search this Thread
Old January 18th, 2007, 04:16 PM   #1
Regular Crew
 
Join Date: Jul 2006
Location: Houston, TX United States
Posts: 39
WS out of focus, may be macro setting

Greetings,

One of the gigs I have is to shoot broll of plays for a theatre in Houston. the camera holds up well in the theatre lighting and colors look gorgeous. However, when I set focus and zoom out wide I've noticed that everything goes a little soft. I decided to play with the camera today to figure it out before my next shoot. I set up in my living room (monitoring the camera on a large TV) and would zoom in on an object in the kitchen, set focus and then zoom out. Sure enough the shot looked very soft once in the WS. Eventually I found my way to turning the macro ring slightly away from it's default position and the wideshot came into focus. I zoomed in and set focus on another object in the kitchen, zoomed out and the wide appeared to be much sharper and in focus. I fine tuned the macro setting by watching a bright light source in a wide shot. When the light source appeared to bloom I would turn the ring in the other direction.

This in mainly something I wanted post incase some else is having the same issue with wide shots going out of focus. If your WS are misteriously out of focus, play the the macro. However, if anyone has any insight on why this is happening I would greatly appreciate it. Is there a way to calibrate your lense's macro setting so your shot is not utlizing the macro focus ring in it's off/locked position?

Thanks,
JC
John Carrithers is offline   Reply With Quote
Old January 18th, 2007, 04:43 PM   #2
Inner Circle
 
Join Date: Feb 2006
Location: Belfast, UK
Posts: 4,121
Sounds like your backfocus needs to be set.

Basically you set the macro ring to the default position, set the exposure so that the iris aperture is wide open. Zoom into a Sieman Star chart set up around 6 feet away, focus with the front focus ring, then zoom out to the wide end of the zoom.

Loosen the small screw on the backfocus adjustment (that's the ring where the macro is located - dont touch the macro). Adjust the backfocus ring until the bundle at the centre of the Siemans star is at it's tightest.

Zoom in again, check the focus with the front focus ring, repeat the backfocus adjustment. You should repeat this procedure until you can see no improvement, then tighten the screw on the backfocus ring. You should check that in tightening the screw you haven't accidentally knocked off the backfocus.

You'll find the instructions in the camera manual. You should check the backfocus regularly - with HD I check it everyday, or if there's a temperature change.
Brian Drysdale is offline   Reply With Quote
Old January 18th, 2007, 04:43 PM   #3
Regular Crew
 
Join Date: Jan 2006
Location: Toronto, CANADA
Posts: 65
Sounds like Back Focus Issue

Hi John,

It sounds like you need to properly set the back focus on your camera. Here is a thread that you might find useful. Download and print out the focus charts and follow the instructions and see if that doesn't resolve your focusing issues.

http://www.dvinfo.net/conf/showthrea...k+focus+charts

Michael Lafleur
Michael Lafleur is offline   Reply With Quote
Old January 18th, 2007, 04:57 PM   #4
Regular Crew
 
Join Date: Jul 2006
Location: Houston, TX United States
Posts: 39
Thanks for the help. I really appreaciate it. I thought it might be the backfocus based on some other information on this forum, but to tell you the truth I had know idea what it was or how to fix it. thanks again.
John Carrithers is offline   Reply With Quote
Old January 18th, 2007, 05:20 PM   #5
Regular Crew
 
Join Date: Jul 2006
Location: Houston, TX United States
Posts: 39
Brilliant. It worked like a charm, thanks so much.
JC
John Carrithers 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 > JVC ProHD & MPEG2 Camera Systems > JVC GY-HD Series Camera Systems

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 03:44 AM.


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