EX1r - Should I use the default picture profile and edit in Post? at DVinfo.net

Silas Barker · January 21st, 2011, 03:44 AM

EX1r -

Should I use the default picture profile and edit in Post to how I want it?
Or use the Picture profile system?

I have already shot a bunch of footage with the default settings so will I be able to get it to look the same with post processing?

Thanks

Vincent Oliver · January 21st, 2011, 06:01 AM

The answer would be dependant on which profile you are using as your default. The CineGamma settings will capture more detail in highlight and shadow areas, which means you can do more with them in post production etc.

Alister Chapman · January 21st, 2011, 06:32 AM

Cinegammas are designed to be graded. The shape of the curve with steadily increasing compression from around 65-70% upwards tends to lead to a flat looking image, but maximises the cameras latitude (although similar can be achieved with a standard gamma and careful knee setting). The beauty of the cinegammas is that the gentle onset of the highlight compression means that grading will be able to extract a more natural image from the highlights. Note than Cinegamma 2 is broadcast safe and has slightly reduced lattitude than CG 1,3 and 4.

Standard gammas will give a more natural looking picture right up to the point where the knee kicks in. From there up the signal is heavily compressed, so trying to extract subtle textures from highlights in post is difficult. The issue with standard gammas and the knee is that the image is either heavily compressed or not, there's no middle ground.

In a perfect world you would control your lighting (turning down the sun if necessary ;-o) so that you could use standard gamma 3 (ITU 709 standard HD gamma) with no knee. Everything would be linear and nothing blown out. This would equate to a roughly 7 stop range. This nice linear signal would grade very well and give you a fantastic result. Careful use of graduated filters or studio lighting might still allow you to do this, but the real world is rarely restricted to a 7 stop brightness range. So we must use the knee or Cinegamma to prevent our highlights from looking ugly.

If you are committed to a workflow that will include grading, then Cinegammas are best. If you use them be very careful with your exposure, you don't want to overexpose, especially where faces are involved. getting the exposure just right with cinegammas is harder than with standard gammas. If anything err on the side of caution and come down 1/2 a stop.

If your workflow might not include grading then stick to the standard gammas. They are a little more tolerant of slight over exposure because skin and foliage won't get compressed until it gets up to the 80% mark (depending on your knee setting). Plus the image looks nicer straight out of the camera as the cameras gamma should be a close match to the monitors gamma.

Vito DeFilippo · January 21st, 2011, 09:23 AM

Great explanation, Alister. Thanks!

Silas Barker · January 21st, 2011, 01:29 PM

I meant that I had no picture profile on by default...... so would it be better to re-shoot what I have shot with a picture profile on, cinegamma probably, or can I still tweak it in post, like add contrast, crush blacks, etc?

Alister Chapman · January 21st, 2011, 04:15 PM

You can still tweak what you have in post. It depends on what you shot. A picture profile won't allow you to shoot things that you can't shoot with no PP on. All it does is optimise things for different scenarios and workflows.

No PP = Standard Gamma 3, Std Matrix, Default detail settings, Auto Knee.

Les Wilson · January 21st, 2011, 05:38 PM

Silas, do a couple experiments with default and some other settings you like. Then see if you can "tweak" the default footage to look the same.

In general, Iean to the philosophy to acquire footage in as true an image as possible and then grade it in post to look the way I want for that project....maybe match it to another camera. Look in the stickies in this forum and search the Picture Profile for posts about True Color. There's a set of them, one for the various gammas. I like TC with Cinegamma 4. YMMV

January 21st, 2011, 03:44 AM	#1
Silas Barker Major Player Join Date: Dec 2009 Location: Sacramento, California Posts: 577	EX1r - Should I use the default picture profile and edit in Post? EX1r - Should I use the default picture profile and edit in Post to how I want it? Or use the Picture profile system? I have already shot a bunch of footage with the default settings so will I be able to get it to look the same with post processing? Thanks

January 21st, 2011, 06:01 AM	#2
Vincent Oliver Trustee Join Date: Sep 2004 Location: Chislehurst, London Posts: 1,724	The answer would be dependant on which profile you are using as your default. The CineGamma settings will capture more detail in highlight and shadow areas, which means you can do more with them in post production etc. __________________ Eyes are a deaf man’s ears. Ears are a blind man’s eyes

January 21st, 2011, 06:32 AM	#3
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	Cinegammas are designed to be graded. The shape of the curve with steadily increasing compression from around 65-70% upwards tends to lead to a flat looking image, but maximises the cameras latitude (although similar can be achieved with a standard gamma and careful knee setting). The beauty of the cinegammas is that the gentle onset of the highlight compression means that grading will be able to extract a more natural image from the highlights. Note than Cinegamma 2 is broadcast safe and has slightly reduced lattitude than CG 1,3 and 4. Standard gammas will give a more natural looking picture right up to the point where the knee kicks in. From there up the signal is heavily compressed, so trying to extract subtle textures from highlights in post is difficult. The issue with standard gammas and the knee is that the image is either heavily compressed or not, there's no middle ground. In a perfect world you would control your lighting (turning down the sun if necessary ;-o) so that you could use standard gamma 3 (ITU 709 standard HD gamma) with no knee. Everything would be linear and nothing blown out. This would equate to a roughly 7 stop range. This nice linear signal would grade very well and give you a fantastic result. Careful use of graduated filters or studio lighting might still allow you to do this, but the real world is rarely restricted to a 7 stop brightness range. So we must use the knee or Cinegamma to prevent our highlights from looking ugly. If you are committed to a workflow that will include grading, then Cinegammas are best. If you use them be very careful with your exposure, you don't want to overexpose, especially where faces are involved. getting the exposure just right with cinegammas is harder than with standard gammas. If anything err on the side of caution and come down 1/2 a stop. If your workflow might not include grading then stick to the standard gammas. They are a little more tolerant of slight over exposure because skin and foliage won't get compressed until it gets up to the 80% mark (depending on your knee setting). Plus the image looks nicer straight out of the camera as the cameras gamma should be a close match to the monitors gamma. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

January 21st, 2011, 09:23 AM	#4
Vito DeFilippo Trustee Join Date: Mar 2006 Location: Montreal, Quebec Posts: 1,585	Great explanation, Alister. Thanks! __________________ . http://www.nosmallroles.com

January 21st, 2011, 04:15 PM	#6
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	You can still tweak what you have in post. It depends on what you shot. A picture profile won't allow you to shoot things that you can't shoot with no PP on. All it does is optimise things for different scenarios and workflows. No PP = Standard Gamma 3, Std Matrix, Default detail settings, Auto Knee. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

January 21st, 2011, 01:29 PM	#5
Silas Barker Major Player Join Date: Dec 2009 Location: Sacramento, California Posts: 577	I meant that I had no picture profile on by default...... so would it be better to re-shoot what I have shot with a picture profile on, cinegamma probably, or can I still tweak it in post, like add contrast, crush blacks, etc?

January 21st, 2011, 05:38 PM	#7
Les Wilson Inner Circle Join Date: Jan 2004 Location: Boca Raton, FL Posts: 3,014	Silas, do a couple experiments with default and some other settings you like. Then see if you can "tweak" the default footage to look the same. In general, Iean to the philosophy to acquire footage in as true an image as possible and then grade it in post to look the way I want for that project....maybe match it to another camera. Look in the stickies in this forum and search the Picture Profile for posts about True Color. There's a set of them, one for the various gammas. I like TC with Cinegamma 4. YMMV