Some advance function explained clearly! at DVinfo.net

Steve Quantrill · March 25th, 2009, 05:19 AM

I've only had my Canon for a week now and find the manual a bit pants in areas to be honest. Can anyone explain the following in simple steps if possible :p

1) What is Auto-KNEE and how is it adjusted on the camera. In manual it only refers to a chart that looks something like a curves filter.

2) How do you adjust colour settings and save them as a custom preset to the memory card and assign it to a custom button.

3) When people talk about crushing the Black, is this something that takes place in post or on the camera itself. If so how is this done and what are the benefits.

4) Where is the backlight option that people refer to, is this something that is a combination of a number of settings or simply a custom preset.

Real newbie here and advice would be appreciated for myself and others I reckon. Cheers

Greg Boston · March 25th, 2009, 05:31 AM

Auto Knee refers to an automatic compression circuit that alters the highlight roll-off (the knee), in response to the current scene. The curved line you referenced is the gamma curve, the shaped response of the sensors to light levels.

Crushing the blacks can happen in camera or in post... again, by manipulating the gamma response curve. Crushing blacks refers to the shadow portion at the lower end of the curve as being a faster roll-off. IOW, things that might normally be almost black, are rendered as black.

Can't help with 2 and 4 since I don't own that specific camera.

-gb-

Robert Dee · March 25th, 2009, 12:33 PM

Steve,

There's a good thread on here about presets that is usually stickied to the top of the XH-A1 forum which will work as a good starting point regarding adjusting how the camera natively records colour and the dynamic range. Coming from a post background, I think its best to get the broadest dynamic range in the camera and then push the whites/crush the blacks in post (This essentially is adjusting the contrast so the blacks are really black and the whites are blown out at the top end) If you do that in camera, you don't have any chance to change in post and even though the raw image looks a little flat, that gives the best data for colour correction. Once again, the thread on presets will go into this.

With regards to setting your own values for custom presets there are a couple of applications out there that will help. Canon has a PC app that will work - if you are on a mac, there is an app with an interface full of sliders but less functionality. I had no problems downloading from those in the thread, adding to a card and copying to the camera and I was new to it. Just make sure you follow the instructions clearly.

Nice to hear from a fellow Brighton resident.

Bobby

Steve Quantrill · March 25th, 2009, 03:29 PM

Thanks Robert. I do feel more comfortable, like you say recording the broadest range and then adjusting in post. I also read a few posts here against this process, something to do with that the compression and data is too large to play with so any work done on the camera is better. Depends on what your trying to achieve I guess. Also helps if you have a HD monitor to plug into live from the camera. I am a post man myself so I have to agree with you, and that's not just a Brighton thing! Great place! :p

Would you say it is best to go with the almost the factory preset (with some small adjustments) for the greatest range?

March 25th, 2009, 05:19 AM	#1
Steve Quantrill New Boot Join Date: Mar 2009 Location: Brighton Posts: 23	Some advance function explained clearly! I've only had my Canon for a week now and find the manual a bit pants in areas to be honest. Can anyone explain the following in simple steps if possible :p 1) What is Auto-KNEE and how is it adjusted on the camera. In manual it only refers to a chart that looks something like a curves filter. 2) How do you adjust colour settings and save them as a custom preset to the memory card and assign it to a custom button. 3) When people talk about crushing the Black, is this something that takes place in post or on the camera itself. If so how is this done and what are the benefits. 4) Where is the backlight option that people refer to, is this something that is a combination of a number of settings or simply a custom preset. Real newbie here and advice would be appreciated for myself and others I reckon. Cheers

March 25th, 2009, 05:31 AM	#2
Greg Boston Wrangler Join Date: Oct 2003 Location: DFW area, TX Posts: 6,117 Images: 1	Auto Knee refers to an automatic compression circuit that alters the highlight roll-off (the knee), in response to the current scene. The curved line you referenced is the gamma curve, the shaped response of the sensors to light levels. Crushing the blacks can happen in camera or in post... again, by manipulating the gamma response curve. Crushing blacks refers to the shadow portion at the lower end of the curve as being a faster roll-off. IOW, things that might normally be almost black, are rendered as black. Can't help with 2 and 4 since I don't own that specific camera. -gb-

March 25th, 2009, 12:33 PM	#3
Robert Dee Tourist Join Date: Jan 2009 Location: Brighton, United Kingdom Posts: 4	Steve, There's a good thread on here about presets that is usually stickied to the top of the XH-A1 forum which will work as a good starting point regarding adjusting how the camera natively records colour and the dynamic range. Coming from a post background, I think its best to get the broadest dynamic range in the camera and then push the whites/crush the blacks in post (This essentially is adjusting the contrast so the blacks are really black and the whites are blown out at the top end) If you do that in camera, you don't have any chance to change in post and even though the raw image looks a little flat, that gives the best data for colour correction. Once again, the thread on presets will go into this. With regards to setting your own values for custom presets there are a couple of applications out there that will help. Canon has a PC app that will work - if you are on a mac, there is an app with an interface full of sliders but less functionality. I had no problems downloading from those in the thread, adding to a card and copying to the camera and I was new to it. Just make sure you follow the instructions clearly. Nice to hear from a fellow Brighton resident. Bobby

March 25th, 2009, 03:29 PM	#4
Steve Quantrill New Boot Join Date: Mar 2009 Location: Brighton Posts: 23	Thanks Robert. I do feel more comfortable, like you say recording the broadest range and then adjusting in post. I also read a few posts here against this process, something to do with that the compression and data is too large to play with so any work done on the camera is better. Depends on what your trying to achieve I guess. Also helps if you have a HD monitor to plug into live from the camera. I am a post man myself so I have to agree with you, and that's not just a Brighton thing! Great place! :p Would you say it is best to go with the almost the factory preset (with some small adjustments) for the greatest range?