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BMPCC, UV/IR Cut and exposure.


Turboguard
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So I've been shooting with the BMPCC since release and many times I've seen the red IR pollution in my footage but never really thought about it much further.

Today I picked up a HOYA UV IR Cut filter and right away did some tests. 

I definitely see a change in some of the footage, but what is mind boggling to me is, why can't I ever seem to get the colors and exposure right on this thing. I see footage from people using the BMPCC and it looks so darn amazing. Some stuff I've shot looks great, while others don't, I just can't seem to figure this out. Please look at the footage and tell me if you have any tips going further with blackmagic design's cameras.

Alas for this test, I changed it to BMD film gama, pushed and pulled gain and lift and a little shadow boost in DaVinci. Then encoded as ProRes 4444XQ and opened in Premiere to add another stop of exposure on all footage plus 380 saturation boost. And finally encode for PP's Vimeo 1080p setting. Let me know if I'm going about this the completely wrong way.

 

Thanks!

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You lose a lot of highlight detail. With raw, use ETTR with 100% zebra. Allow the sun (the perfect circle) and artificial light sources (zebra should appear within the sharp form of i.e, the light bulb) to clip, but never reflections. There is a lot of lost detail on the walls. Of course this could also be a matter of insufficient highlight recovery in Resolve. Use the luma waveform to see how your values are mapped.

You can of course deliberately lose detail. If, for example, you have faces in the sun at noon, it can be better to let the sky clip. The sky is always several stops brighter than anything else, and imo there is no point in trying to get an HDR image then. In extreme cases, you can even cause noise in sun shadows (even on faces) if you don't sacrifice the sky. We all know how a sky looks anyway. A professional DoP would bounce the faces but sometimes let the sky clip nevertheless. In Hollywood, as everyone knows, there is always blue sky, and not many things can be more boring.

 

Alas for this test, I changed it to BMD film gama, pushed and pulled gain and lift and a little shadow boost in DaVinci. Then encoded as ProRes 4444XQ and opened in Premiere to add another stop of exposure on all footage plus 380 saturation boost. And finally encode for PP's Vimeo 1080p setting. Let me know if I'm going about this the completely wrong way.

I think so. You can do everything in Resolve. The tools there are much better. Add saturation (and everything) with more nodes. Turn on soft clip. And if a Vimeo upload file is all you want, you can as well deliver in ProRes422 ...

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Wow! You've only just got a UV/IR cut filter - one thing you'll find with the Hoya is that you'll get a slight green tinge in certain conditions.

With the BMPCC exposure is key & ETTR is not always the best policy to take - or should that be over-ETTR.

I no longer shoot RAW with this, since the ProRes HQ is jaw dropping as it is & has significantly less moire etc... For ProRes you can push or pull 2 stops, so I put zebras to 80% and either hit it spot on or slightly clipping (as Axel said, this isn't HDR filming - its all to do with the look you're after or the conditions you find yourself in). This camera is also surprising in low light, it cleans up really nice, but I like the grain/noise that this camera produces - no need to add in post, just get it done in camera.

One thing that I have noticed recently, is that you really need to boost the saturation - go over the top & then pull it down.

Also, if you're in a pinch (timewise) then the Video mode is actually pretty damn good for colour rendition - this really surprised me, since at the beginning it wasn't that great (one of the Firmware's sorted it).

Video mode might be a good way to really hone your exposure skills - cripple the camera in order to force yourself to hit exposure pretty much spot on & make decisions about Shadows vs. Highlights. Then once you know how to get what you want, pretty much in-camera, then move to Film mode or Raw in order to really see how much you can go crazy.

The Screen is just there for focusing (I noticed you've got the Zacuto) & its fine for that - I punch in&out going by eye, rather than use peeking. The Zebras/Histogram obviously help with exposure, but again sometimes you've got to just trust your eyes.

The main thing to do is to test, test, test before you shoot something - you'll get no funny surprises.

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Thanks for the replies.

Okay, went back into DaVinci. Here's what I did (does it matter if I added it to my core node?). 

 

EDIT: First image (and in Vimeo clip) I have Highlight recovery on. When turned off the wall looks white again? Why does it do that?

Screen Shot 2015-08-13 at 11.16.09 AM.png

Screen Shot 2015-08-13 at 11.19.44 AM.png

What's going on with those pink highlights?

Check my images above, it looks like highlight recovery made my highlights more red, and I don't know the exact science behind that... Why would I ever use it if it just ruins my image?

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Wow! You've only just got a UV/IR cut filter - one thing you'll find with the Hoya is that you'll get a slight green tinge in certain conditions.

With the BMPCC exposure is key & ETTR is not always the best policy to take - or should that be over-ETTR.

I no longer shoot RAW with this, since the ProRes HQ is jaw dropping as it is & has significantly less moire etc... For ProRes you can push or pull 2 stops, so I put zebras to 80% and either hit it spot on or slightly clipping (as Axel said, this isn't HDR filming - its all to do with the look you're after or the conditions you find yourself in). This camera is also surprising in low light, it cleans up really nice, but I like the grain/noise that this camera produces - no need to add in post, just get it done in camera.

One thing that I have noticed recently, is that you really need to boost the saturation - go over the top & then pull it down.

Also, if you're in a pinch (timewise) then the Video mode is actually pretty damn good for colour rendition - this really surprised me, since at the beginning it wasn't that great (one of the Firmware's sorted it).

Video mode might be a good way to really hone your exposure skills - cripple the camera in order to force yourself to hit exposure pretty much spot on & make decisions about Shadows vs. Highlights. Then once you know how to get what you want, pretty much in-camera, then move to Film mode or Raw in order to really see how much you can go crazy.

The Screen is just there for focusing (I noticed you've got the Zacuto) & its fine for that - I punch in&out going by eye, rather than use peeking. The Zebras/Histogram obviously help with exposure, but again sometimes you've got to just trust your eyes.

The main thing to do is to test, test, test before you shoot something - you'll get no funny surprises.

Thanks for all your tips! I've been shooting in Film mode with screen set to Video. I am thinking about purchasing the SmallHD 501 so I can add different LUT's to somewhat balance my image before hand. I feel like such a newbie, but is that a good idea?

Very rarely you will have all channels clip evenly. And Turbogards highlights are particularly badly balanced, as his waveform confirms.

I didn't know you could shoot unbalanced highlights personally, how do you avoid something like that? I do see that the RGB's are all over the place.

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This is fun, I deleted all my changes and went back to only adjusting under the camera raw tab. I changed my initial WB to 4570 and got a green tone so change my tint +18, and also added the saturation in there instead of under my primary coloring. Things looked way better already, just not as saturated as I wanted so also added more saturation under my primary coloring tab. I'm just confused why the WB is so off in camera. Still looks like the IR/UV was a much needed purchase though. 

 

EDIT: What still boggles me is that white wall on the right hand side changing hue... What's up with that?

Screen Shot 2015-08-13 at 1.06.19 PM.png

 

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EDIT: What still boggles me is that white wall on the right hand side changing hue... What's up with that?

Screen Shot 2015-08-13 at 1.06.19 PM.png

 

It's a crap shoot with Blackmagic on what's going to be jacked up when you review the footage in post. I got so tired of it. I shot an entire music video with fresnels hitting the side of the lens for a cool effect. Monitored on a pretty big screen and it looked fine. I get home to start editing and added contrast, freaking grid lines started appearing out of nowhere. I'm in love with their image but I can't wait for the day when everything just runs smooth.

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It's a crap shoot with Blackmagic on what's going to be jacked up when you review the footage in post.

No it's not.  As was stated he clipped the highlights and as with any camera highlights rarely clip evenly.

You can of course deliberately lose detail. If, for example, you have faces in the sun at noon, it can be better to let the sky clip. The sky is always several stops brighter than anything else, and imo there is no point in trying to get an HDR image then. In extreme cases, you can even cause noise in sun shadows (even on faces) if you don't sacrifice the sky. We all know how a sky looks anyway. A professional DoP would bounce the faces but sometimes let the sky clip nevertheless. In Hollywood, as everyone knows, there is always blue sky, and not many things can be more boring.

I personally avoid clipping as much as possible.  I think one of the biggest problems with digital video is clipped clouds.  As you yourself pointed out weird things can happen when you clip.  Clipping less gives more room for smooth highlight roll off.  Of course there are times when you have to clip but I don't go crazy with it.  A bit of noise to me is less noticeable than badly clipped highlights.

What I find baffling is I use Prores HQ 99% of the time and I've never seen highlights like this guy is getting.  I wouldn't trade whatever noise I am getting for the terribly clipped highlights he's getting.

If I am shooting indoors with a window in the scene then I have to make decisions or in an extreme back lit situation.

I think everything in moderation.  I never set my zebras to 100%.  I give myself a little breathing room to avoid clipping just one or two channels unknowingly.  It's been stated numerous times that if you set zebras to 100% one channel may clip and the indicator won't necessarily give you are warning.  I also don't push things very far in low contrast scenes.  Unless it is a high dynamic range scene I don't push things right up to the clipping limit.

Turboguard should really just experiment.  Do exposures and take notes.  See what works.  Try and be methodical about it.  Honestly though going this long without a UVIR filter with a blackmagic pocket is a bit much.  Turboguard, you need to search the web for Blackmagic specific resources and experiment.

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Yes it is. Clipped highlights aside.

We are discussing clipped highlights in this thread.  You are making this guy's highlight problem seem common and unique to BMPCC.  I saw this guy's thread yesterday and I didn't respond.  The reason I didn't respond is I saw all that pink everywhere and I hadn't ever seen it before in a BMPCC clip.  I didn't have a solution because I wasn't familiar with the problem.  Lumping these shots in with a grab bag of other issues and claiming it's a common problem is a thorough misrepresentation.  I am not a pro nor an expert on the BMPCC.  But even with my inexperience and incompetence I never encountered massive fields of pink in multiple shots neither have I seen that result on other videos I've seen on the internet.  Either his camera is broken or it's being used in an unusual fashion.

And if you shoot raw and do an extreme ETTR on ANY camera you can't judge what the final image will look like till you process the raw files.  That has nothing to do with Blackmagic.

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We are discussing clipped highlights in this thread.  You are making this guy's highlight problem seem common and unique to BMPCC.  I saw this guy's thread yesterday and I didn't respond.  The reason I didn't respond is I saw all that pink everywhere and I hadn't ever seen it before in a BMPCC clip.  I didn't have a solution because I wasn't familiar with the problem.  Lumping these shots in with a grab bag of other issues and claiming it's a common problem is a thorough misrepresentation.  I am not a pro nor an expert on the BMPCC.  But even with my inexperience and incompetence I never encountered massive fields of pink in multiple shots neither have I seen that result on other videos I've seen on the internet.  Either his camera is broken or it's being used in an unusual fashion.

And if you shoot raw and do an extreme ETTR on ANY camera you can't judge what the final image will look like till you process the raw files.  That has nothing to do with Blackmagic.

I also commented that I've never seen that pink highlight situation, and added that in my experience it's a crap shoot on strange problems (never seen before) to pop up. I'm rooting so hard for Blackmagic b/c their image is stunning. I've owned a BMCC, and BMPCC. To me it just got so frustrating with oddball quirks that I haven't used them much lately unless it's a very relaxed schedule shoot, and/or I'm able to review the footage shot with a LUT.

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I agree with Aaron, it almost feels like I have to be lucky to not run into problems. Sometimes it works wonderfully, other times little stuff like this will pop up in certain clips. 

 

I will ill upload the RAW sequence in a bit and show you (whoever's interested) that I, according to the built in histogram and zebras (95%) exposed the image good with barely any clipping. I mean, the bars in the front are outside in the shadow but still black, so I really closed down for this one shot. Will be back in a bit.

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Thanks for all your tips! I've been shooting in Film mode with screen set to Video. I am thinking about purchasing the SmallHD 501 so I can add different LUT's to somewhat balance my image before hand. I feel like such a newbie, but is that a good idea?

I didn't know you could shoot unbalanced highlights personally, how do you avoid something like that? I do see that the RGB's are all over the place.

Yeah, the SmallHD 501 will help you since you'll be able to get an impression of what the final image will/might look like - but in the end, you'll be avoiding the issue of learning how your camera works.

The other thing i forgot to mention is the use of ASA & your choice can really help or hinder the shots.

I am assuming you're using ND filters?

The pink you're experiencing is what we all do when white object/things are way over exposed - normally happens when the sun (as in your case) is directly hitting a surface (the white wall).

As someone said - Zebras should never be at 100% with ProRes (70-80% when you're starting out & then maybe 90% once you're used to the camera). The BMPCC is not a DSLR & as with all cameras you need to learn how it works/behaves in certain situations - try, test & make notes.

Remember, at lot of info about ETTR is for RAW & not ProRes - in a well lit area/scene there is no need to ETTR, in a badly lit area/scene there are more benefits (but only by about 2 stops or so).

go to BMCUSER & do a search for things you're unsure about - ASA & ETTR should be your first stops.

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Yeah, the SmallHD 501 will help you since you'll be able to get an impression of what the final image will/might look like - but in the end, you'll be avoiding the issue of learning how your camera works.

The other thing i forgot to mention is the use of ASA & your choice can really help or hinder the shots.

I am assuming you're using ND filters?

The pink you're experiencing is what we all do when white object/things are way over exposed - normally happens when the sun (as in your case) is directly hitting a surface (the white wall).

As someone said - Zebras should never be at 100% with ProRes (70-80% when you're starting out & then maybe 90% once you're used to the camera). The BMPCC is not a DSLR & as with all cameras you need to learn how it works/behaves in certain situations - try, test & make notes.

Remember, at lot of info about ETTR is for RAW & not ProRes - in a well lit area/scene there is no need to ETTR, in a badly lit area/scene there are more benefits (but only by about 2 stops or so).

go to BMCUSER & do a search for things you're unsure about - ASA & ETTR should be your first stops.

Yeah, I know what you're saying and feel like I do have the hang of it. I've been shooting with it for about 2 years now. I don't shoot ProRes personally, and I have my Zebra's set to 95% and then try to avoid them even there because I've fucked up shots having them set to 100 and then using ETTR on top of that. For this specific shot, I shot 200 ASA cause I would clip so extremely on 400 and 800. And yes I was using ND, probably 7 extra stops (My speedbooster was set to "2" and I used the Sigma ART 18-35mm). I just have to be more careful I guess. Thanks everyone for your inputs.

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Yeah, I know what you're saying and feel like I do have the hang of it. I've been shooting with it for about 2 years now. I don't shoot ProRes personally, and I have my Zebra's set to 95% and then try to avoid them even there because I've fucked up shots having them set to 100 and then using ETTR on top of that. For this specific shot, I shot 200 ASA cause I would clip so extremely on 400 and 800. And yes I was using ND, probably 7 extra stops (My speedbooster was set to "2" and I used the Sigma ART 18-35mm). I just have to be more careful I guess. Thanks everyone for your inputs.

Just keep at it, you seem to be doing things ok - you might just need more/stronger ND & to stop down on the lens a little more.

I've been battling with trying to get a useable TimeLapse from the BMPCC & it proved a little tricky at first.

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Having the Zebra at 95% makes pretty much no difference from a hundred.  Better to go lower if you want to be safe.

I have been shooting with 100% Zebra, ETTR, Genus ND and No IR cut for years... Zero issues, no pink highlights, no pollution.

I do pretty much the same for prores as raw. 

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Having the Zebra at 95% makes pretty much no difference from a hundred.  Better to go lower if you want to be safe.

I have been shooting with 100% Zebra, ETTR, Genus ND and No IR cut for years... Zero issues, no pink highlights, no pollution.

I do pretty much the same for prores as raw. 

I keep hearing about this Genus ND (is it fader ND?), and I use Tiffen Vari myself. Should I maybe change?

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