Saturday, August 20, 2016

Re: [Avid-L2] Slate Form Needed

 

I can't prove you wrong but given what a traditional slate is for why would the same not apply for a dpx sequence?  All my typical show delivery files have slates with Network information, Series Title, episode title, TRT, Frame Rate, Progressive vs. Interlace, audio configuration, Record Date, Network NOC identification numbers that the network specifies to assist them in file tracking.

For my DPX Netflix deliveries there was no slate as they only want one second of black at top and bottom.  There file naming convention includes all the above data they are concerned with.  Now I'm fairly new to DPX files so I don't have a handle on what descriptive metadata is built into each frame but I bet there is plenty in there to tell the frame rate and color space info.  IIRC there must be fps type data as when importing a dpx into say Avid it would know what the actual running time should be and not just blindly import it like a targa sequence.  I haven't ever tried to bring in say a 23.976 dpx into a 59.94i project to see what really happens.  If I did the above and ama linked to the dpx sequence would Avid properly timewarp the clip to proper running time?

Meanwhile back to the slate question.  I see no reason not to include a slate like I would for a normal show master file along with bars and tone.  Of course the audio would be in separate file(s) given dpx doesn't support audio in most applications.  Someone on an earlier thread I think mentioned there was some dpx format that stored audio in metadata of the frames but it wasn't a format that seemed to have any practical support so I don't know if that is even possible but conventional usage has audio separate.  There may be color space, raster size and original scan type and frame rate data that would be more crucial to have in the slate information.  Perhaps the DPX bit depth whether it's 10,12 or 16 etc.. might be needed.  I'd find out from the folks you are delivering to what they want/need on the slate.



---In Avid-L2@yahoogroups.com, <bouke@...> wrote :

Hi David, been a long time!

Not in my best mood, but here is my take.
If a DPX sequence needs a visual alate, EVERYONE in the WHOLE chain is a moron.
(a text file next to the folder 'should' do the trick' )

Please someone prove me wrong….


Bouke

VideoToolShed.com
van Oldenbarneveltstraat 33
6512 AS  Nijmegen
+31 24 3553311
To send files, go here:

On Aug 20, 2016, at 06:41, David Dodson davaldod@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

I'm just a simple, unassuming offline editor. But to make a long story short, I have to create a slate for a DPX master for a feature. So what I'm needing to figure out is what all goes on this slate. Is there any kind of current template for this sort of thing? Any counsel or references would be most appreciated.

Thanks!

David Dodson
davidadodson@...
818-523-0905




Bouke

Edit 'B / VideoToolShed.com
van Oldenbarneveltstraat 33
6512 AS  Nijmegen
+31 24 3553311

__._,_.___

Posted by: bigfish@pacbell.net
Reply via web post Reply to sender Reply to group Start a New Topic Messages in this topic (3)

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Re: [Avid-L2] Slate Form Needed

 

Hi David, been a long time!

Not in my best mood, but here is my take.
If a DPX sequence needs a visual alate, EVERYONE in the WHOLE chain is a moron.
(a text file next to the folder 'should' do the trick' )

Please someone prove me wrong….


Bouke

VideoToolShed.com
van Oldenbarneveltstraat 33
6512 AS  Nijmegen
+31 24 3553311
To send files, go here:

On Aug 20, 2016, at 06:41, David Dodson davaldod@gmail.com [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

I'm just a simple, unassuming offline editor. But to make a long story short, I have to create a slate for a DPX master for a feature. So what I'm needing to figure out is what all goes on this slate. Is there any kind of current template for this sort of thing? Any counsel or references would be most appreciated.

Thanks!

David Dodson
davidadodson@sbcglobal.net
818-523-0905




Bouke

Edit 'B / VideoToolShed.com
van Oldenbarneveltstraat 33
6512 AS  Nijmegen
+31 24 3553311

__._,_.___

Posted by: Bouke <bouke@editb.nl>
Reply via web post Reply to sender Reply to group Start a New Topic Messages in this topic (2)

Have you tried the highest rated email app?
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this is the Avid-L2

.

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Friday, August 19, 2016

[Avid-L2] Slate Form Needed

 

I'm just a simple, unassuming offline editor. But to make a long story short, I have to create a slate for a DPX master for a feature. So what I'm needing to figure out is what all goes on this slate. Is there any kind of current template for this sort of thing? Any counsel or references would be most appreciated.

Thanks!

David Dodson
davidadodson@sbcglobal.net
818-523-0905

__._,_.___

Posted by: David Dodson <davaldod@gmail.com>
Reply via web post Reply to sender Reply to group Start a New Topic Messages in this topic (1)

Have you tried the highest rated email app?
With 4.5 stars in iTunes, the Yahoo Mail app is the highest rated email app on the market. What are you waiting for? Now you can access all your inboxes (Gmail, Outlook, AOL and more) in one place. Never delete an email again with 1000GB of free cloud storage.

this is the Avid-L2

.

__,_._,___

Re: [Avid-L2] Workflow for Indie Feature now Lot's of LUTS

 

Millivolts may describe the size of the container but not the quantity or value of the "information' contained within. It may be black, which is effectively "null" or every pixel could have a different value (maximum data). But even if every pixel has a different value, this may just be noise, also arguably a "null" set. 

More importantly, millivolts only quantify the video container after it becomes a video signal. Log operates on the data BEFORE it becomes video. It is a remapping of the raw sensor data into the video signal that maximizes the potential of the optical information represented in the video stream. 

Now, using the prior analogy, one can argue that there is less data in a Log signal than a Rec709 signal, at least from the point of view of a human viewer. But from the point of view of software that can manipulate the digital data, there can be information that would not have been captured in a Rec709 signal.

Granted, it may not be a lot more information, and it is not always better. The difference is only meaningful when comparing the two in optimized conditions. Hence, if you don't shoot Log correctly, you just make your life more difficult.

Cheers,
             tod 

On Aug 19, 2016, at 12:00 PM, bigfish@pacbell.net [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

The millivolts are a representation of the data whether it is compressed in a manner like LogC or some other choice or linear.  They are a direct representation of the binary numbers that have been stored to represent the image.  If there is less range to the millivolts then there is less detail or fewer steps in the actual levels being recorded.  It's a Look Up Table so the data values get remapped accordingly.  I know nature and humans perceive things in a log manner in both audio and video.  The math behind all the transforms is something I have lost the ability to cypher like I could back in my  engineering college years and even then I never got to the level of sophistication things like codecs and LogC transforms are doing in this case.

On my most Keep It Simple Stupid mode I would think if the math of the LogC transform used the full 700 millivolt range there would be more inherent detail to be had that could then be interpreted in a manner that is best for the particular system in use.  If limited to Rec 709 map accordingly and if going to Resolve or other systems that employ floating point math then remap to a much greater range from the full 700 millivolts of detail/steps of levels.

In my simplistic mind I understand that LogC will lessen the detail in the shadows and bright areas.  If I were to shoot in a controlled environment a calibrated Light Box with a perfect black to white ramp that in a pure Rec 709 world as a perfect diagonal line from 0 to 700 millivolts on my scope and then repeated that exact same thing only transforming the signal to LogC and then back to 709 emulating the LogC workflow would I not see more stair stepping in the diagonal line at the lower levels and upper levels as a result of the way the LogC favors detail in the mid tones?  I'm not saying that this scientific experiment is a true indication of something the viewer would see as bad when it comes to a real image but this is what the science I'm trying to understand suggests to me.


As you say, "The issue for us is not really whether log contains more information, but rather whether it contains more useful information."  This is where it gets into an even more grey area, no pun intended, for me.  I know LUTs aren't going to go away so I'm trying to dig as much under the hood so I can better trouble shoot and deal with the various footage I get.

I did stumble on to some actual camera bars from one of our Panasonic Varicam35 VLog shoots and looking at what appeared to be 100% bars I did see full 0 to 700 millivolts on the scope with or without the Vlog to Rec 709 LUT applied.  What I did see what a big difference in chroma with the unlutted material low in chroma and displaying a quadrature error.  Then with the LUT applied the vector dots were closer to the 100% boxes but there was still a fair amount of quadrature error.  I don't know exactly what the Camera Bars levels really are, would there be a different signal for color bars in 20/20 color space as opposed to Rec 709.  I would think so based on what I see when I look at my scope and toggle between differing color spaces in Avid projects but I don't know what the Varicam 35 generates as a test signal.  It was the first time I got a clip with some bars on it from the Vari 35 so I was excited but still left confused.

---In avid-l2@yahoogroups.com, <hoplist@...> wrote :

On Aug 19, 2016, at 1:28 AM, bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

When I see that I have 700 millivolts of range and it's now condensed into 500 to 550 millivolts of range there is clearly some detail being lost.

You cannot measure data in millivolts. That is a measure of the container, not a measure of the information in the container.

There is a revolution in data storage based on escaping preconceptions of the connection between "information" and the quanta of storage. Consider "a picture contains a thousands words." To fully convey all the information in a photo of a room would require many thousands of words, consuming many, many pages of paper and you could never convey all of the information in the picture. The picture is a more efficient way of conveying a certain type of information. And it is possible to convey that complete picture using a stunningly small amount of energy.

The issue for us is not really whether log contains more information, but rather whether it contains more useful information.

Cheers,
              tod
 


__._,_.___

Posted by: hoplist@hillmanncarr.com
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Re: [Avid-L2] Workflow for Indie Feature now Lot's of LUTS

 

LogC is a storage medium not meant to be viewed directly without a interpretive LUT or color correction placed on top. I call LogC "DBX for video".

Nice analogy. And yet, a surprising number of people seem to end up with (or even want?) that "Light My Fire" look. :-)


Jim "not too obscure here, right?" Feeley

jim feeley
pov media
word image sound





On Aug 19, 2016, at 12:41 AM, Tom McD ltr54@sbcglobal.net [Avid-L2] <Avid-L2@yahoogroups.com> wrote:


John,
For feature work yes shooting logC 
makes sense. For a lesser budget show with compressed post time that's a tougher decision. I've seen top DP's shoot both ways with equal success. People monitor and judge exposure by how the LogC signal looks. That by itself should tell you how uninformed people are of and how the LogC signal displays information.

LogC is a storage medium not meant to be viewed directly without a interpretive LUT or color correction placed on top. I call LogC "DBX for video".

Tom McDonnell
818-675-1501

Sent from my iPhone

On Aug 19, 2016, at 12:23 AM, Tom McD <ltr54@sbcglobal.net> wrote:

John,
LogC today is the fanboy rah rah of "must get every useless stop of unneeded range."  Honestly it's made shooting HD or 2k or 4K almost as easy as shooting film neg.


Tom McDonnell
818-675-1501

Sent from my iPhone

On Aug 18, 2016, at 10:28 PM, bigfish@pacbell.net [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

Well I am a colorist although my realm is not high end work for the most part.  Your gallon of milk analogy is not quite accurate but a good starting point.  In my world it's more like the gallon of milk is condensed to fit into a quart container in a manner that isn't always turned back into the original gallon but one with some curds in it.  When I see that I have 700 millivolts of range and it's now condensed into 500 to 550 millivolts of range there is clearly some detail being lost.  It's simply the fact that there are fewer steps with less range hence less detail.  As I said clearly the general consciences is it's more valuable to not clip or lose shadow detail.  In my perfect world it would be more effective to expose for the delivery color space.  In other words I shoot into the quart container, I color correct in the quart container and I serve in a quart container.  Then I'd be getting the full 700 millivolts of detail that Rec 709 affords.  At some point it's going to be in a quart container and having done it that way for decades I have a handle on things.  Now I get logC from the world of marginal cameras and the LUTs in a generic form or those I get from the field aren't very usable.  Like I said the Arri LogC, Panasonic V-Log, Sony S3 Gamut and other Sony incarnations have been pretty reliable but the cannons and God knows what others I will get handed have no consistency and whether that's because of improper exposure or just bad math in the LUTs I don't know.  I don't expect the LUT to be the final say but a decent starting point and with the latter cameras I've mentioned I always seem to be starting from scratch without a clear indication of what was intended in the field.

What I do know it using LUTs in Avid in the 4K world is a big performance hog but assume they are more tolerable in the HD realm.  Most of my HD LUTed work I pre-process in Resolve so I haven't w! orked with the Avid internal LUTs in HD much.

My experience and opinions are based in the real world I live in where I don't have enough time as it is and adding LUTs has not streamlined my end of the food chain hence I am less of a fan than those with bigger budgets and more time to spend fine tuning.  If I want to be theoretical then over all LUTs are great for not clipping things and having more latitude to tweak and correct for errors later but I'll take footage from the Camera people I've worked with for decades shooting without LUTs who know how to expose over LUTs most of the time. 

From earlier in this thread:
Pat wrote:
"I'd go even further than Tod and say shooting Log and not adjusting exposure accordingly is worse than straight Rec709.
Log is about trading bit depth in some areas of exposure to gain latitude. Don't need or use the latitude and you are just losing."

This comment speaks to what I'm talking about, especially, "Don't need or use the latitude and you are just losing."  So while I may be wrong if I'm trying to make the most pristine possible image given enough time to tweak.  I don't think I'm wrong in the arena I work in.  When I start getting into Resolve and other higher end color systems I may feel differently but with the turn around time of round tripping I have yet to work on those systems for the color end of things. 




---In Avid-L2@yahoogroups.com, <cutandcover@...> wrote :

It's almost comical how you are arguing in essence the exact opposite view of what these things are supposed to help you with. Or maybe not help you, but help someone else (like a colorist).

Log footage is not losing low/highlight info. It's retaining it! It's great at doing that if properly exposed. Think about it this way: 

- your shot is a gallon of water
- your camera can only hold a quart
- linear says pick a quart of the shot and put it in the camera, that's all you can take
- log says squish the gallon in, it will fit into the quart container if you do it my way
- in post, log says AAAAAAAHHHHH all this room is great I can stretch my quart back out to gallon size!

Compare the linear quart to the log gallon and see how much more you actually wound up with - the log is almost always more detailed and a better representation of the available light of the original shot.

LUT is a starting point ALWAYS. It is never really designed to be the end. So if you want a quick reconfiguration of the log footage into something reasonably linear, use a LUT - it's like a one-light.

Almost any colorist you or I know will either use a LUT and work from there, or abandon the LUT and work from scratch.



On Thu, Aug 18, 2016 at 4:44 PM, bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:
 

I am of the opinion that properly shot Rec 709 that is intended to be delivered in Rec 709 is technically superior to shooting LogC.  While this may be technically true it is not common practice these days as everyone has opted to shoot LogC under the assumption it's going to give me more to work with in post.  When you say it trades big depth in some areas of exposure I would think it trades bit resolution more so than bit depth.  In my basic understanding the top and bottom of exposure are rolled off so they have fewer steps or millivolts of data range at the top and bottom.  To me that would mean that a gradient would have more banding in the high and low exposure areas.  This is how I view it but please correct me if this is wrong.

From the most basic stand point when I get Arri LogC the un lutted range on my scope is typically 100 to 550/600 millivolts.  Right away the exposure modification of the sensor data has left a 100 or more millivolts of potential image contrast/detail at the top and bottom lost.  I realize the idea behind the LogC is to avoid clipping and try and take the data from the more optimal range of the sensor.  So once you've compressed the image contrast using the LogC math when you stretch it back out you are adding noise to some degree and I would assume the quantizing steps are stretched out so some subtlety of detail is being lost.  I have just assumed the lack of clipping etc... outways these inherent issue.  For me LUTs are pain than gain but I realize I seem to be in the minority in this area.  Every time I have to color correct just to get to a square one of the basic look it takes more time and time is not something I get much of.  In my experience the whole Log workflows get confused in many ways and as you say when things are not properly exposed in Log things are more work to correct.  Arri LogC, Sony S3 Gamut etc..., and Panasonic Vlog seem to play pret! ty nice but I've battled footage from Cannon c300 log that had no consistency so I could not apply a generic LUT to all the footage so it just became easier to drop Luts and color correct each shot.  That is where I have the most issue  with Luts in my world.



---In Avid-L2@yahoogroups.com, <pat@...> wrote :

I'd go even further than Tod and say shooting Log and not adjusting exposure accordingly is worse than straight Rec709.
Log is about trading bit depth in some areas of expisure to gain latitude. Don't need or use the latitude and you are just losing.

Pat from his mobile.




__._,_.___

Posted by: Jim Feeley <jfeeley@gmail.com>
Reply via web post Reply to sender Reply to group Start a New Topic Messages in this topic (16)

Have you tried the highest rated email app?
With 4.5 stars in iTunes, the Yahoo Mail app is the highest rated email app on the market. What are you waiting for? Now you can access all your inboxes (Gmail, Outlook, AOL and more) in one place. Never delete an email again with 1000GB of free cloud storage.

this is the Avid-L2

.

__,_._,___

Re: [Avid-L2] Workflow for Indie Feature now Lot's of LUTS

 

The millivolts are a representation of the data whether it is compressed in a manner like LogC or some other choice or linear.  They are a direct representation of the binary numbers that have been stored to represent the image.  If there is less range to the millivolts then there is less detail or fewer steps in the actual levels being recorded.  It's a Look Up Table so the data values get remapped accordingly.  I know nature and humans perceive things in a log manner in both audio and video.  The math behind all the transforms is something I have lost the ability to cypher like I could back in my  engineering college years and even then I never got to the level of sophistication things like codecs and LogC transforms are doing in this case.

On my most Keep It Simple Stupid mode I would think if the math of the LogC transform used the full 700 millivolt range there would be more inherent detail to be had that could then be interpreted in a manner that is best for the particular system in use.  If limited to Rec 709 map accordingly and if going to Resolve or other systems that employ floating point math then remap to a much greater range from the full 700 millivolts of detail/steps of levels.

In my simplistic mind I understand that LogC will lessen the detail in the shadows and bright areas.  If I were to shoot in a controlled environment a calibrated Light Box with a perfect black to white ramp that in a pure Rec 709 world as a perfect diagonal line from 0 to 700 millivolts on my scope and then repeated that exact same thing only transforming the signal to LogC and then back to 709 emulating the LogC workflow would I not see more stair stepping in the diagonal line at the lower levels and upper levels as a result of the way the LogC favors detail in the mid tones?  I'm not saying that this scientific experiment is a true indication of something the viewer would see as bad when it comes to a real image but this is what the science I'm trying to understand suggests to me.


As you say, "The issue for us is not really whether log contains more information, but rather whether it contains more useful information."  This is where it gets into an even more grey area, no pun intended, for me.  I know LUTs aren't going to go away so I'm trying to dig as much under the hood so I can better trouble shoot and deal with the various footage I get.

I did stumble on to some actual camera bars from one of our Panasonic Varicam35 VLog shoots and looking at what appeared to be 100% bars I did see full 0 to 700 millivolts on the scope with or without the Vlog to Rec 709 LUT applied.  What I did see what a big difference in chroma with the unlutted material low in chroma and displaying a quadrature error.  Then with the LUT applied the vector dots were closer to the 100% boxes but there was still a fair amount of quadrature error.  I don't know exactly what the Camera Bars levels really are, would there be a different signal for color bars in 20/20 color space as opposed to Rec 709.  I would think so based on what I see when I look at my scope and toggle between differing color spaces in Avid projects but I don't know what the Varicam 35 generates as a test signal.  It was the first time I got a clip with some bars on it from the Vari 35 so I was excited but still left confused.

---In avid-l2@yahoogroups.com, <hoplist@...> wrote :

On Aug 19, 2016, at 1:28 AM, bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

When I see that I have 700 millivolts of range and it's now condensed into 500 to 550 millivolts of range there is clearly some detail being lost.

You cannot measure data in millivolts. That is a measure of the container, not a measure of the information in the container.

There is a revolution in data storage based on escaping preconceptions of the connection between "information" and the quanta of storage. Consider "a picture contains a thousands words." To fully convey all the information in a photo of a room would require many thousands of words, consuming many, many pages of paper and you could never convey all of the information in the picture. The picture is a more efficient way of conveying a certain type of information. And it is possible to convey that complete picture using a stunningly small amount of energy.

The issue for us is not really whether log contains more information, but rather whether it contains more useful information.

Cheers,
              tod
 

__._,_.___

Posted by: bigfish@pacbell.net
Reply via web post Reply to sender Reply to group Start a New Topic Messages in this topic (15)

Have you tried the highest rated email app?
With 4.5 stars in iTunes, the Yahoo Mail app is the highest rated email app on the market. What are you waiting for? Now you can access all your inboxes (Gmail, Outlook, AOL and more) in one place. Never delete an email again with 1000GB of free cloud storage.

this is the Avid-L2

.

__,_._,___

Re: [Avid-L2] Re: Workflow for Indie Feature now Lot's of LUTS

 

I like the comparison to DBX and if it worked as seamlessly as DBX did, audio folks please tell me if I'm wrong in my limited understanding of DBX it did work in a uniform manner didn't it?  It's where it's not just a transform and untransform that I get frustrated.  Something like Dolby B IIRC for audio cassettes was painless and just an on off choice.  If every LogC to Rec 709 LUT worked as well as my experience with the Arri LogC to Rec 709 I wouldn't be so whiny about this.

Tom, when you say,  "Honestly it's made shooting HD or 2k or 4K almost as easy as shooting film neg." does that mean film neg was easy to shoot?  I'm not being sarcastic here but I never spent much time working with film other than some Film School projects at UCLA.  I know my news camera friends that grew up shooting reversal film really knew how to expose properly because that was very unforgiving as far as I know.  When you say as easy as film neg are referring to the number of allowable stops film neg has or is film neg much more adjustable in terms of color timing and printing or both.  I just never viewed shooting film as easy but always was more comfortable with a video camera and a waveform on set.



---In avid-l2@yahoogroups.com, <ltr54@...> wrote :

John,
For feature work yes shooting logC 
makes sense. For a lesser budget show with compressed post time that's a tougher decision. I've seen top DP's shoot both ways with equal success. People monitor and judge exposure by how the LogC signal looks. That by itself should tell you how uninformed people are of and how the LogC signal displays information.

LogC is a storage medium not meant to be viewed directly without a interpretive LUT or color correction placed on top. I call LogC "DBX for video".

Tom McDonnell
818-675-1501

Sent from my iPhone

On Aug 19, 2016, at 12:23 AM, Tom McD <ltr54@...> wrote:

John,
LogC today is the fanboy rah rah of "must get every useless stop of unneeded range."  Honestly it's made shooting HD or 2k or 4K almost as easy as shooting film neg.


Tom McDonnell
818-675-1501

Sent from my iPhone

On Aug 18, 2016, at 10:28 PM, bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

Well I am a colorist although my realm is not high end work for the most part.  Your gallon of milk analogy is not quite accurate but a good starting point.  In my world it's more like the gallon of milk is condensed to fit into a quart container in a manner that isn't always turned back into the original gallon but one with some curds in it.  When I see that I have 700 millivolts of range and it's now condensed into 500 to 550 millivolts of range there is clearly some detail being lost.  It's simply the fact that there are fewer steps with less range hence less detail.  As I said clearly the general consciences is it's more valuable to not clip or lose shadow detail.  In my perfect world it would be more effective to expose for the delivery color space.  In other words I shoot into the quart container, I color correct in the quart container and I serve in a quart container.  Then I'd be getting the full 700 millivolts of detail that Rec 709 affords.  At some point it's going to be in a quart container and having done it that way for decades I have a handle on things.  Now I get logC from the world of marginal cameras and the LUTs in a generic form or those I get from the field aren't very usable.  Like I said the Arri LogC, Panasonic V-Log, Sony S3 Gamut and other Sony incarnations have been pretty reliable but the cannons and God knows what others I will get handed have no consistency and whether that's because of improper exposure or just bad math in the LUTs I don't know.  I don't expect the LUT to be the final say but a decent starting point and with the latter cameras I've mentioned I always seem to be starting from scratch without a clear indication of what was intended in the field.

What I do know it using LUTs in Avid in the 4K world is a big performance hog but assume they are more tolerable in the HD realm.  Most of my HD LUTed work I pre-process in Resolve so I haven't w! orked with the Avid internal LUTs in HD much.

My experience and opinions are based in the real world I live in where I don't have enough time as it is and adding LUTs has not streamlined my end of the food chain hence I am less of a fan than those with bigger budgets and more time to spend fine tuning.  If I want to be theoretical then over all LUTs are great for not clipping things and having more latitude to tweak and correct for errors later but I'll take footage from the Camera people I've worked with for decades shooting without LUTs who know how to expose over LUTs most of the time.

From earlier in this thread:
Pat wrote:
"I'd go even further than Tod and say shooting Log and not adjusting exposure accordingly is worse than straight Rec709.
Log is about trading bit depth in some areas of exposure to gain latitude. Don't need or use the latitude and you are just losing."

This comment speaks to what I'm talking about, especially, "Don't need or use the latitude and you are just losing."  So while I may be wrong if I'm trying to make the most pristine possible image given enough time to tweak.  I don't think I'm wrong in the arena I work in.  When I start getting into Resolve and other higher end color systems I may feel differently but with the turn around time of round tripping I have yet to work on those systems for the color end of things.




---In Avid-L2@yahoogroups.com, <cutandcover@...> wrote :

It's almost comical how you are arguing in essence the exact opposite view of what these things are supposed to help you with. Or maybe not help you, but help someone else (like a colorist).

Log footage is not losing low/highlight info. It's retaining it! It's great at doing that if properly exposed. Think about it this way: 

- your shot is a gallon of water
- your camera can only hold a quart
- linear says pick a quart of the shot and put it in the camera, that's all you can take
- log says squish the gallon in, it will fit into the quart container if you do it my way
- in post, log says AAAAAAAHHHHH all this room is great I can stretch my quart back out to gallon size!

Compare the linear quart to the log gallon and see how much more you actually wound up with - the log is almost always more detailed and a better representation of the available light of the original shot.

LUT is a starting point ALWAYS. It is never really designed to be the end. So if you want a quick reconfiguration of the log footage into something reasonably linear, use a LUT - it's like a one-light.

Almost any colorist you or I know will either use a LUT and work from there, or abandon the LUT and work from scratch.



On Thu, Aug 18, 2016 at 4:44 PM, bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:
 

I am of the opinion that properly shot Rec 709 that is intended to be delivered in Rec 709 is technically superior to shooting LogC.  While this may be technically true it is not common practice these days as everyone has opted to shoot LogC under the assumption it's going to give me more to work with in post.  When you say it trades big depth in some areas of exposure I would think it trades bit resolution more so than bit depth.  In my basic understanding the top and bottom of exposure are rolled off so they have fewer steps or millivolts of data range at the top and bottom.  To me that would mean that a gradient would have more banding in the high and low exposure areas.  This is how I view it but please correct me if this is wrong.

From the most basic stand point when I get Arri LogC the un lutted range on my scope is typically 100 to 550/600 millivolts.  Right away the exposure modification of the sensor data has left a 100 or more millivolts of potential image contrast/detail at the top and bottom lost.  I realize the idea behind the LogC is to avoid clipping and try and take the data from the more optimal range of the sensor.  So once you've compressed the image contrast using the LogC math when you stretch it back out you are adding noise to some degree and I would assume the quantizing steps are stretched out so some subtlety of detail is being lost.  I have just assumed the lack of clipping etc... outways these inherent issue.  For me LUTs are pain than gain but I realize I seem to be in the minority in this area.  Every time I have to color correct just to get to a square one of the basic look it takes more time and time is not something I get much of.  In my experience the whole Log workflows get confused in many ways and as you say when things are not properly exposed in Log things are more work to correct.  Arri LogC, Sony S3 Gamut etc..., and Panasonic Vlog seem to play pret! ty nice but I've battled footage from Cannon c300 log that had no consistency so I could not apply a generic LUT to all the footage so it just became easier to drop Luts and color correct each shot.  That is where I have the most issue  with Luts in my world.



---In Avid-L2@yahoogroups.com, <pat@...> wrote :

I'd go even further than Tod and say shooting Log and not adjusting exposure accordingly is worse than straight Rec709.
Log is about trading bit depth in some areas of expisure to gain latitude. Don't need or use the latitude and you are just losing.

Pat from his mobile.


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