View Full Version : Flash Banding
Pete Cofrancesco September 4th, 2019, 04:29 PM I’m thinking of filming an upcoming wedding with the Sony A7iii. I’ve been brushing up by watching some behind the scenes videos on Youtube.
A recent video I was watching I noticed some really bad flash banding (if that’s the right term) using the Sony A7. Is this a known issue or is there a shutter or frame rate setting that eliminates or minimizes this effect?
You can see what I’m talking about at the reception entrance 8:50
https://m.youtube.com/watch?v=pEfhgIw3Vkw&t=556s
Jeff Pulera September 5th, 2019, 01:38 PM You're going to get that with most any camera these days really. The old CCD camcorders would get a flash across the entire frame, but the newer CMOS sensors used the last several years read out the data top to bottom sequentially rather than all at once, so you get a flash across just part of the image rather than the whole frame.
I believe there is a software plugin to repair that if so inclined
Thanks
Jeff
Pete Cofrancesco September 5th, 2019, 04:10 PM If the whole frame flashed white it look more natural than those weird white bars. I don't remember seeing them on my Canon 70/80d
Jeff Pulera September 6th, 2019, 08:45 AM When I went from a Sony VX-2000 (Mini DV) with CCD sensor to the FX-7 (HDV) camera with CMOS sensor for weddings maybe a dozen years ago, that is when flash-banding started for me. Very annoying, yes, ruins slow-motion shots for sure!!!
CCDs had a "global shutter" that would read out the entire frame of video in same instant, thus any flash applied to the entire frame. CMOS sensors use a "rolling shutter" that reads out the image data line by line, thus the bent vertical lines during fast pans. Like shooting out a car window, the telephone poles lean over to one side, or airplane propellers are weirdly bent/warped, because the subject continues moving while being scanned into the frame of video so it's at different places in different parts of the image.
So basically what you want is a camera with "global shutter" which is unfortunately a rarity these days.
From WikiPedia-
Rolling shutter is a method of image capture in which a still picture or each frame of a video is captured not by taking a snapshot of the entire scene at a single instant in time but rather by scanning across the scene rapidly, either vertically or horizontally.
Thanks
Christopher Young September 6th, 2019, 11:01 AM A recent video I was watching I noticed some really bad flash banding (if that’s the right term) using the Sony A7.
Probably the least painful and quickest solution to flash banding correction is to use Sony's "Catalyst Browse" which you can download and then use its Flash Band Correction tool. I haven't used it in Catalyst Browse but I have used it in Sony's older Content Browser software and it did a surprisingly decent job. Catalyst Browse is a free tool so maybe give it ago. Otherwise there are a number of Flash Band plugins around though don't have any experience with them.
Chris Young
Sydney
https://www.sonycreativesoftware.com/catalystbrowse
Chris Harding September 6th, 2019, 07:51 PM When I was still shooting on my Sony EA-50 I also had to use the Content Browser software for wedding receptions on a regular basis to rid the footage of banding. However when I moved over to Panasonic the problem vanished ...not sure if they have inbuilt firmware to deal with the issue but both cameras were CMOS and as far as I know Sony actually make Panny's sensors. I wonder if it's a sensor size issue as my current cameras are only 1"sensors and my Sony's used APSC sensors???
Christopher Young September 7th, 2019, 02:07 AM You are 100% correct Chris. Panasonic did indeed introduce flash band correction in camera about ten years back. They called it "Advanced Flash Band Compensation (FBC)" All late model Sony professional video cameras also have this function now. To the best of my knowledge I don't think any of the Panasonic or Sony mirrorless cameras have this flash band function.
Reference to it in this Panasonic brochure.
https://pro-av.panasonic.net/en/sales_o/broch_pdf/aj-px270.pdf
Chris Young
Chris Harding September 7th, 2019, 06:32 AM Thanks Chris
Always a fountaIn of knowledge!! A year or so back I was shooting weddings on my Panasonic FZ1000 bridge cameras with the 1" Sony sensor and never had any banding issues at all. I try to keep my wedding shoots down to live broadcasting the afternoon ceremony only and then heading home! The 1:00am finish time at wedding receptions as well as multiple camera edits every week got to me so I dropped out of the rat race!!
Pete Cofrancesco September 7th, 2019, 10:31 AM You are 100% correct Chris. Panasonic did indeed introduce flash band correction in camera about ten years back. They called it "Advanced Flash Band Compensation (FBC)" All late model Sony professional video cameras also have this function now.
Thanks I'll have to try that out.
It occurred to me I have a flash so I could test my current cameras out. To my surprise both my Canon 70d DSLR (aps c sensor) and Panasonic UX90 camcorder (1" sensor) exhibited similar flash banding, although they seem more natural because the banding takes up most of the frame. I'm guessing the banding is narrower on the A7 because it can't capture as much due to the resolution and sensor size.
I saw this video which had a good explanation.
https://youtu.be/ivnp2l712eI
Pete Cofrancesco September 7th, 2019, 10:46 AM Thanks Chris
The 1:00am finish time at wedding receptions as well as multiple camera edits every week got to me so I dropped out of the rat race!!
I don't blame you. I only do a wedding here and there because of all the time and stress that goes into it. I'm still debating how many unmanned cameras, batteries etc...
Chris Harding September 8th, 2019, 02:13 AM Hey Pete
I just do ceremonies now (only do receptions for special friends) and use just one camera on a 3 wheeled dolly and basically live broadcast and edit on the fly eith on camera or through my computer and livestream studio ...it essentially means I can pack up at the end of a ceremony and I'm done ..no editing !! Too many people here and buying discount cameras and advertising themselves as "wedding videographers" and charging next to nothing!! Took a while to educate brides what a live broadcast is but they are getting the idea and it's a lot easier than spending the entire day shooting and the following week editing!!
David Barnett September 8th, 2019, 05:55 PM I don't blame you. I only do a wedding here and there because of all the time and stress that goes into it. I'm still debating how many unmanned cameras, batteries etc...
I'd recommend considering how many locations/travel etc is involved. All at one location, outdoor ceremony, you can probably do 3+ cameras. Bridal prep at a hotel, mass at a catholic church, photos at a park, reception at a venue/country club? Don't break yourself setting up & breaking down too much gear. You'll find it's not the cameras that are the problem, its the tripods, and factor in, wedding timelines almost always run late. So if it says 'Arrive at venue at 6', figure you'll arrive at 6:30, need to rush in & unpack, shoot the venue, tables, cake, details, and get your other cameras up & ready for 7pm Introductions. Things like that.
There's also insurance, and tripping hazards in the dark, which is why I'm also somewhat stubborn on only 2 tripods, 1 unmanned. People run all over at these to take a photo with their Iphone. If you have a GoPro or small DSLR you could use for a trick shot once or twice in the highlights vid bring it, otherwise I don't recommend 3 cams if shooting solo but that's just my suggestion, maybe at the church but you'll find sometimes they leave pretty quick while you're still packing up.
Pete Cofrancesco September 8th, 2019, 08:55 PM I'd recommend considering how many locations/travel etc is involved. All at one location, outdoor ceremony, you can probably do 3+ cameras. Bridal prep at a hotel, mass at a catholic church, photos at a park, reception at a venue/country club? Don't break yourself setting up & breaking down too much gear. You'll find it's not the cameras that are the problem, its the tripods, and factor in, wedding timelines almost always run late. So if it says 'Arrive at venue at 6', figure you'll arrive at 6:30, need to rush in & unpack, shoot the venue, tables, cake, details, and get your other cameras up & ready for 7pm Introductions. Things like that.
There's also insurance, and tripping hazards in the dark, which is why I'm also somewhat stubborn on only 2 tripods, 1 unmanned. People run all over at these to take a photo with their Iphone. If you have a GoPro or small DSLR you could use for a trick shot once or twice in the highlights vid bring it, otherwise I don't recommend 3 cams if shooting solo but that's just my suggestion, maybe at the church but you'll find sometimes they leave pretty quick while you're still packing up.
I hate shooting solo. You’re right about guarding against wrangling too much equipment. This one is “easy” because it’s all at one venue. I know what I want just a matter of planning it out right and fighting the urge to do too much. Wouldn’t it be nice if I could just shoot with one camera on a monopod and only deliver a highlight movie?
My main concern, I’ve never tried shooting with two full frame mirrorless cameras, especially how to handle using the second unmanned with that shallow dof. Closing down the aperture only buys you so much latitude and you can’t trust it on auto focus. I usually just use a camcorder as my unmanned then I don’t have to worry about time limit, battery life, or focus. I still could use the camcorder but then you get two unmatched looking cameras.
The two difficult situations to shoot solo that require a 2nd camera are the ceremony and the toasts. For the ceremony I like over the shoulder for both the bride and groom and wide safety. For the toasts you need one of the couple and the other on the speaker.
Yeah and moving between the various parts of the wedding...
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