BMPCC 3D LUT appear overexposed at DVinfo.net

Frank Grygier · March 21st, 2015, 08:39 AM

When I apply a LUT or use FilmConvert in Premiere CC the footage appears way over exposed. I get similar results when using Raw or Prores. Any thoughts.

Gary Huff · March 23rd, 2015, 07:42 AM

How are you exposing your image?

Chris Medico · March 23rd, 2015, 07:58 AM

It could be that you have exposed your image above the design.

I also would like to know what tools you are using to measure exposure and what values you are exposing to.

Frank Grygier · March 23rd, 2015, 11:42 AM

I generally use the histagram on the Pocket Cinema Camera and 100 zebras for the highlights.Is it critical to expose to the right for the best results wen using a LUT. Any thought on VisionColor ImpulZ? - 35mm Film Emulation LUTs

Thanks

Chris Medico · March 23rd, 2015, 12:32 PM

Can you post some images that show where you are exposing things?

Do you have a grey card? That is an essential tool to shooting LOG or RAW.

Chris Medico · March 23rd, 2015, 12:56 PM

I just checked out some examples on their website and they are setting skin tones between 40% and 60%.

Where are your skin tones falling on your exposure?

Chris Medico · March 23rd, 2015, 01:01 PM

Here is what I measure.

Frank Grygier · March 24th, 2015, 01:23 PM

Thanks for your guidance. I will get a screen shot for you this evening.

Frank Grygier · March 24th, 2015, 01:24 PM

So skin tones are about middle grey?

Gary Huff · March 24th, 2015, 05:53 PM

Quote:

Originally Posted by Frank Grygier

So skin tones are about middle grey?

No, they should be around 60IRE.

Frank Grygier · March 24th, 2015, 09:11 PM

Got it.
Thanks for putting me on the right track.

Gary Huff · March 24th, 2015, 09:12 PM

Actually, I should clarify that 60IRE is for Rec.709. So once you de-log the footage, it should ideally be in that range.

Chris Medico · March 25th, 2015, 03:30 AM

The thing to do is to buy a grey card and do some exposure tests. That will allow you to know exactly what you should expose to for the best results with your LUT of choice.

As an example when I shoot S-LOG the design for that curve is for mid grey to be at 38IRE. If I stay close to that my LUT works well. LOG isn't RAW so that exposure won't work for you.

With a $20 grey card and a few hours playing around with your camera you'll be able to get it dialed in just right and have a great method for nailing your exposure on set. Remember to keep the card square to the lens. Don't tilt it up or down. Straight at the lens.

Frank Grygier · March 25th, 2015, 08:38 AM

I do have a grey card but have neglected to use it. I have been relying on zebras and histogram.I will do some testing and get back to you all with the results. I can see now that I am overexposing the footage.

Thanks to you all. It is great to have this forum.

Alex Humphrey · June 16th, 2017, 02:34 PM

I'm on a different camera currently, but I'm finding the same answer for 709 Log as well as raw cameras is an incident light meter. Middle grey 35-40 IRE seems to be the most common middle ground on most cameras, 709, Log, and raw.. so maybe try it out or meter a grey card to read around 35%-38%. My Lumu ($59 at amazon) light meter ball that plugs into my iPod touch and $29 Cine Meter II app work well, though a real light meter that doesn't have a iPod touch running an app would be better, but more expensive.

March 21st, 2015, 08:39 AM	#1
Frank Grygier Regular Crew Join Date: Feb 2006 Location: Austin,TX Posts: 125	BMPCC 3D LUT appear overexposed When I apply a LUT or use FilmConvert in Premiere CC the footage appears way over exposed. I get similar results when using Raw or Prores. Any thoughts. Last edited by Frank Grygier; March 21st, 2015 at 08:42 AM. Reason: mix spell

March 23rd, 2015, 07:42 AM	#2
Gary Huff Inner Circle Join Date: Jan 2013 Location: Austin, Texas Posts: 2,006	Re: BMPCC 3D LUT appear overexposed How are you exposing your image?

March 23rd, 2015, 07:58 AM	#3
Chris Medico Inner Circle Join Date: Aug 2006 Location: Efland NC, USA Posts: 2,322	Re: BMPCC 3D LUT appear overexposed It could be that you have exposed your image above the design. I also would like to know what tools you are using to measure exposure and what values you are exposing to. __________________ http://www.LandYachtMedia.com

March 23rd, 2015, 11:42 AM	#4
Frank Grygier Regular Crew Join Date: Feb 2006 Location: Austin,TX Posts: 125	Re: BMPCC 3D LUT appear overexposed I generally use the histagram on the Pocket Cinema Camera and 100 zebras for the highlights.Is it critical to expose to the right for the best results wen using a LUT. Any thought on VisionColor ImpulZ? - 35mm Film Emulation LUTs Thanks

March 23rd, 2015, 12:32 PM	#5
Chris Medico Inner Circle Join Date: Aug 2006 Location: Efland NC, USA Posts: 2,322	Re: BMPCC 3D LUT appear overexposed Can you post some images that show where you are exposing things? Do you have a grey card? That is an essential tool to shooting LOG or RAW. __________________ http://www.LandYachtMedia.com

March 23rd, 2015, 12:56 PM	#6
Chris Medico Inner Circle Join Date: Aug 2006 Location: Efland NC, USA Posts: 2,322	Re: BMPCC 3D LUT appear overexposed I just checked out some examples on their website and they are setting skin tones between 40% and 60%. Where are your skin tones falling on your exposure? __________________ http://www.LandYachtMedia.com

March 23rd, 2015, 01:01 PM	#7
Chris Medico Inner Circle Join Date: Aug 2006 Location: Efland NC, USA Posts: 2,322	Re: BMPCC 3D LUT appear overexposed Here is what I measure. Attached Thumbnails __________________ http://www.LandYachtMedia.com

March 24th, 2015, 01:23 PM	#8
Frank Grygier Regular Crew Join Date: Feb 2006 Location: Austin,TX Posts: 125	Re: BMPCC 3D LUT appear overexposed Thanks for your guidance. I will get a screen shot for you this evening.

March 24th, 2015, 01:24 PM	#9
Frank Grygier Regular Crew Join Date: Feb 2006 Location: Austin,TX Posts: 125	Re: BMPCC 3D LUT appear overexposed So skin tones are about middle grey?

March 24th, 2015, 09:11 PM	#11
Frank Grygier Regular Crew Join Date: Feb 2006 Location: Austin,TX Posts: 125	Re: BMPCC 3D LUT appear overexposed Got it. Thanks for putting me on the right track.

March 24th, 2015, 09:12 PM	#12
Gary Huff Inner Circle Join Date: Jan 2013 Location: Austin, Texas Posts: 2,006	Re: BMPCC 3D LUT appear overexposed Actually, I should clarify that 60IRE is for Rec.709. So once you de-log the footage, it should ideally be in that range.

March 25th, 2015, 03:30 AM	#13
Chris Medico Inner Circle Join Date: Aug 2006 Location: Efland NC, USA Posts: 2,322	Re: BMPCC 3D LUT appear overexposed The thing to do is to buy a grey card and do some exposure tests. That will allow you to know exactly what you should expose to for the best results with your LUT of choice. As an example when I shoot S-LOG the design for that curve is for mid grey to be at 38IRE. If I stay close to that my LUT works well. LOG isn't RAW so that exposure won't work for you. With a $20 grey card and a few hours playing around with your camera you'll be able to get it dialed in just right and have a great method for nailing your exposure on set. Remember to keep the card square to the lens. Don't tilt it up or down. Straight at the lens. __________________ http://www.LandYachtMedia.com

March 25th, 2015, 08:38 AM	#14
Frank Grygier Regular Crew Join Date: Feb 2006 Location: Austin,TX Posts: 125	Re: BMPCC 3D LUT appear overexposed I do have a grey card but have neglected to use it. I have been relying on zebras and histogram.I will do some testing and get back to you all with the results. I can see now that I am overexposing the footage. Thanks to you all. It is great to have this forum.

June 16th, 2017, 02:34 PM	#15
Alex Humphrey Major Player Join Date: Mar 2007 Location: california North and South Posts: 642	Re: BMPCC 3D LUT appear overexposed I'm on a different camera currently, but I'm finding the same answer for 709 Log as well as raw cameras is an incident light meter. Middle grey 35-40 IRE seems to be the most common middle ground on most cameras, 709, Log, and raw.. so maybe try it out or meter a grey card to read around 35%-38%. My Lumu ($59 at amazon) light meter ball that plugs into my iPod touch and $29 Cine Meter II app work well, though a real light meter that doesn't have a iPod touch running an app would be better, but more expensive.