Dark corners on footage? at DVinfo.net

Go Back   DV Info Net > Special Interest Areas > Wedding / Event Videography Techniques

Wedding / Event Videography Techniques
Shooting non-repeatable events: weddings, recitals, plays, performances...


Reply
 
Thread Tools Search this Thread
Old May 9th, 2006, 09:06 AM   #1
Regular Crew
 
Join Date: Oct 2003
Location: San Diego
Posts: 34
Dark corners on footage?

Would someone please explain to me why I'm getting dark spots in the corners of my video footage. I'm using a one chip Sony camera and the only thing on the lens is a UV filter. I do zoom in sometimes. Here is a short movie and you can see what I mean about the dark spots in the corners.
http://homepage.mac.com/richsheikh/weddingday/

Rich
Rich Sheikh is offline   Reply With Quote
Old May 9th, 2006, 09:34 AM   #2
Wrangler
 
Join Date: Apr 2003
Location: Philadelphia, PA
Posts: 2,898
I'm unable to view QT where I'm logging in from but from your description what your describing is lense vignetting.

http://www.vanwalree.com/optics/vignetting.html
__________________
Glen Elliott
Cord 3 Films
Glen Elliott is offline   Reply With Quote
Old May 9th, 2006, 09:38 AM   #3
Major Player
 
Join Date: Jan 2006
Location: Ogden, UT
Posts: 349
Looks like slight vignetting from the UV filter. The lens is wide enough (or the filter sticks out far enough) that it is barely getting into the corners of the imaging area. On a regular TV you wouldn't even notice these because of the overscan. And even on this clip online it was difficult to pick out, certainly not a big distraction.
Mike Oveson is offline   Reply With Quote
Old May 9th, 2006, 10:19 AM   #4
Major Player
 
Join Date: Feb 2006
Location: Surrey, UK
Posts: 680
Hi there, I can certainly clarify that you won't see those minor black areas on TV screens as I get those from my new wide-angle lens! I knew I should have bought the Sony-branded one instead! :)

You could always crop the movie slightly if you're worried about the way it looks in websites.


Just out of interest, I've noticed that some clips that are posted (as with yours) show scenes dissolving but with the end frame remining static! is that deliberate? Each to their own obviously, but I find it distracting, does anyone else? Sorry I really don't mean to offend, I'm just curious?
Richard Wakefield is offline   Reply With Quote
Old May 9th, 2006, 10:20 AM   #5
Regular Crew
 
Join Date: Mar 2006
Location: Salt Lake City, Utah
Posts: 29
I wouldn't have noticed the vignetting if you hadn't pointed it out, but what I'd do is shoot a white wall at full wide zoom with and without the UV filter. That way you'll find out if it's the filter or the lens itself. If it's the filter you might try a photo store—I think there are thinner filters available that might solve your problem.
Francois Camoin is offline   Reply With Quote
Old May 9th, 2006, 11:58 AM   #6
Major Player
 
Join Date: Jun 2004
Location: Oxfordshire, UK
Posts: 416
Quote:
Originally Posted by Richard Wakefield
Just out of interest, I've noticed that some clips that are posted (as with yours) show scenes dissolving but with the end frame remining static! is that deliberate? Each to their own obviously, but I find it distracting, does anyone else? Sorry I really don't mean to offend, I'm just curious?
I think you'll find that's how iMovie does cross-dissolves - it removes the need for handles on the clips, but causes the out-going frame to freeze during the dissolve - which you may find OK, you may not...
__________________
Martin at HeadSpin HD on Blu-ray
Martin Mayer is offline   Reply With Quote
Old May 9th, 2006, 03:08 PM   #7
Major Player
 
Join Date: Feb 2006
Location: Surrey, UK
Posts: 680
Ah, that explains it! I'm not familiar with iMovie...I can also see that would make sense for quickening edit times too.
Oh, and sorry for deviating from the vignetting thread!
Richard Wakefield is offline   Reply With Quote
Old May 9th, 2006, 04:02 PM   #8
Major Player
 
Join Date: Sep 2003
Location: Rego Park , NYC
Posts: 649
There are two types of dissolves in iMovie...one is the straight cross dissolve..and the other is the "overlap" where the last frame from the previous clip is "frozen" and then fades while the new section comes in.

Depends on what you want.

Sometimes you want to "freeze frame" a moment and make it linger.
John C. Chu is offline   Reply With Quote
Old May 9th, 2006, 04:09 PM   #9
Regular Crew
 
Join Date: Oct 2003
Location: San Diego
Posts: 34
Thanks everyone, I don't believe its IMovie because I've used that cross desolve many times within other movie projects and don't have that problem. It seems to happen when I zoom in while shooting. Thanks to you all, I now suspect vignetting from the UV filter. I'll try a test and see what happens.
Rich Sheikh is offline   Reply With Quote
Old May 9th, 2006, 05:17 PM   #10
Major Player
 
Join Date: Jun 2004
Location: Oxfordshire, UK
Posts: 416
Quote:
Originally Posted by Rich Sheikh
Thanks everyone, I don't believe its IMovie because I've used that cross desolve many times within other movie projects and don't have that problem. It seems to happen when I zoom in while shooting. Thanks to you all, I now suspect vignetting from the UV filter. I'll try a test and see what happens.
I wasn't suggesting iMovie was resonsible for your vignetting - rather that it was responsible for the cross-dissolve behaviour Richard Wakefield had noticed.

I think it's the UV filter too. Simple question - are you always at the widest zoom setting when it occurs? If so....
__________________
Martin at HeadSpin HD on Blu-ray
Martin Mayer is offline   Reply With Quote
Old May 9th, 2006, 05:21 PM   #11
Regular Crew
 
Join Date: Oct 2003
Location: San Diego
Posts: 34
You know, I'm not sure. I'll run that test also. Thanks
Rich Sheikh 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 > Wedding / Event Videography Techniques

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 12:24 PM.


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