Slightly Off Colors with a Very Inexperienced OperatorColor JVCHD Church
Posted 12 June 2013 - 08:12 AM
I have no training in cinematography. I started volunteering at my church about 8 months ago. At that time, they needed a camera operator, so I filled the position. I really enjoy working the cameras each week, but every time a problem arises, it takes me a good few days of studying online to be able to solve what's most likely a simple solution.
This time, the problem is that the technical director constantly tells me that "camera 2's" colors always seem off. Now, both cameras are exactly the same: they are both JVC-HM750CHU, both on the same tripod with the same settings, sat 4 feet from each other.
I'm not sure how the colors could go off as the lighting is always the same, the positioning is always the same, and no one ever touches the settings(although there are other camera operators, so I can't say that with complete certainty)
There aren't any professional cinematographers who can help with this issue, and embarrassingly enough, I know the most about them, solely due to my fascination with the art. The only signs we have are a Star Chart and a Pontdumonde color chart, but we don't have a wave form/vectorscope as I've seen "instructional" videos use.
I know when I signed up, they said that if I don't receive any answers that its probably because what I post can't be answered in a few lines, but I'm not really looking for step-by-step instructions on how to solve this. What I really need is just for someone to tell me that there's no way to fix this with my current equipment/knowledge, a link of someone else explaining the techniques required, or Anything really...
I truly do appreciate any advice anyone has to offer, and I apologize if I posted this in the wrong board or if it did not meet topic requirements. Thank you very much for your time.
Posted 12 June 2013 - 09:06 AM
Presumably you've tried white balancing the cameras on a bit of white card, or something? If they're nearby each other, you can do it more or less simultaneously, so there shouldn't be any concern over things being inconsistent.
If they still don't match, check you don't have any sort of colour options loaded into them. I'm not intimately familiar with 750, but it'll certainly have a variety of black and white level, gamma, matrix and colorimetry options. Exactly which of these you need to look at rather depends on the exact characteristics of the mismatch you're seeing, so I can't be more specific. Can you grab some images demonstrating the problem and post them?
You are of course not using any automatic features - they can't be expected to produce consistency between cameras. Likewise, is it something as trivial as different exposure settings, such as iris, shutter, or automated anti-flicker features? Are you using the same lenses on both cameras?
Oh, and, edit: sometimes, ostensibly identical cameras actually don't produce identical output. Sensors can vary, which is where we start tweaking those internal settings.
Posted 12 June 2013 - 09:32 AM
Thank you so much for the extensive reply! I neglected to mention the fact that we white balance every week.
We are using the same lens for both cameras. All the settings are set to manual and were last adjusted long before I started working there some 8 months ago.
Unfortunately, I cannot get any images until Sunday at the earliest. The cameras stay locked up until then. I can understand that seeing the color differences could lead a trained eye to noting the lack of or over saturation of a certain color or aspect. I know the settings you're talking about, but they're fairly extensive and in a language I'm not familiar with that it scares away from playing with the options.
I am very appreciative of your help. Thank you very much for your insight.
Posted 12 June 2013 - 10:00 AM
I just had a quick skim through the manual.
The first thing you could try is to simply hit the "status" button and look at what it says after "Setup File" in the viewfinder. Both the cameras should be identical. If a bullet point is displayed by the name of the currently-selected setup file, changes have been made. This may not entirely diagnose the problem as I'm not sure exactly what's stored in a file and what isn't, but it would exclude a lot of things.
Beyond that you're just going to have to dive in and have a play. Setup files represent both a way to store the current setup and a way to recall a factory setup (probably several different factory setups, in fact), so it should be possible to play nondestructively. You're unlikely to do much damage as it doesn't sound like you're in a situation where you need them set up in any particularly outlandish fashion. Most of the selection of factory options will probably produce images that are acceptable to you. Usually they just include slightly punchier, more saturated, or mellow and desaturated options, etc., which are unlikely to be objectionable.
Make sure one of them hasn't mistakenly been switched into auto white balance, too. Oldest one in the book. Often they'll still let you take a white balance, but won't actively use it until you select a non-auto option. The 750 manual also mentions that you can assign fixed auto-white (FAW) to any of the Preset, A, or B functions on the physical white-balance switch. Check this hasn't been done. It may say "FAW" or similar in the viewfinder if this is the case.
Most of the camera paint options (in the "camera process" part of the menu system) seem to have a "normal" setting. This is the sort of thing that would usually be stored in a setup file, but it may be worth a quick look through.
I could go on but it's better that you go and have a look, or better yet spring the cameras from prison, take them home, and spend a few hours getting into them in a relaxed environment. I suspect it's probably simpler than any of these issues, anyway.
Posted 12 June 2013 - 10:09 AM
Where are you seeing this mismatch? Is it live in the room on a monitor? Or are you talking about a mis-match once the footage has been brought to the edit. If it's just sitting there in the monitor, it could be a monitor problem.
Else Phil nails everything with cameras.
Posted 12 June 2013 - 11:26 AM
First thing is to make sure the difference isn't between the two monitors... if you could feed the same image to both monitors, that would be a fast way of seeing the difference. I'd also then put both zooms on the same camera to see if the color of the lens matches.
If the monitors aren't the problem, nor the zooms, I'd also see if the two cameras match when a preset white balance is used versus one you created manually.
You also have to make sure all internal settings are the same in terms of the color matrix, gamma, knee sat, etc.
Posted 12 June 2013 - 12:16 PM
Posted 14 June 2013 - 12:05 PM
Here's a great way to get pro with any camera. Take it home with the manual and read every page! The camera settings being set 8 months ago is the first problem. Once you get a chance to read the book cover to cover you will gain the confidence to get in and adjust settings as well as understand them. Simple things like black shading and setting white balance will not be overwhelming. You may just want to reset both camera to factory and set up your own look as well!