Shutter speed for keying with blue screen?

VMP wrote on 6/20/2016, 9:20 AM
Do you have any advice when it comes to shutter speed when shooting for blue screen keying ?
I live in the PAL world so shooting 50i with the Sony HXR NX5, I set everything manually the shutter speed is set at 100. So kept the 'two times the frame rate' rule for the shutter speed.

Below is a sample video of the keying that've done with the setting mentioned above I am happy with it.
But I am curious about your experience.

There are basically no fast movements in this clip, as reference you can use his hand movement between 00:01-00:04 I don't mind some motion blur though.

All done within Vegas and BCC studio.




Thanks,
VMP

Comments

OldSmoke wrote on 6/20/2016, 9:54 AM
If you can, shoot progressive.

BTW: "two times the frame rate" we live in the digital age and that is no longer a must.

Proud owner of Sony Vegas Pro 7, 8, 9, 10, 11, 12 & 13 and now Magix VP15&16.

System Spec.:
Motherboard: ASUS X299 Prime-A

Ram: G.Skill 4x8GB DDR4 2666 XMP

CPU: i7-9800x @ 4.6GHz (custom water cooling system)
GPU: 1x AMD Vega Pro Frontier Edition (water cooled)
Hard drives: System Samsung 970Pro NVME, AV-Projects 1TB (4x Intel P7600 512GB VROC), 4x 2.5" Hotswap bays, 1x 3.5" Hotswap Bay, 1x LG BluRay Burner

PSU: Corsair 1200W
Monitor: 2x Dell Ultrasharp U2713HM (2560x1440)

videoITguy wrote on 6/20/2016, 9:59 AM
VMP, you forgot one key ingredient to the relative success of keying - the format/codec of your key footages.... makes a big difference on success quality - uncompressed 4-2-2 will do the trick.

Your twice frame-rate rule is fine, but by no means the spelling of best results.

In order:
1) Lighting, lighting, lighting
2) Format of key footage
3) the app/helper plug-in used to create and execute key
4) frame rate, shutter speed, (more light into each frame the better upto the point of motion blur happening
K-Decisive wrote on 6/20/2016, 10:10 AM
a bit random, but:
I do like to shoot 90 degree as apposed to 180 to reduce motion blur and get a better key, esp on (long) hair.

(I use AE instead of BCC, so I'm not sure if the same/similar plug-ins are avail.)

I then use RSMB (real smart motion blur, which is a third party add on) in After effects to re-simulate 'normal' motion blur after the keying process.

I would also like to recommend spill slayer, does a much better job of reducing spill then the stock spill reduction in Key-light.
VMP wrote on 6/20/2016, 10:57 AM
Thank you all for your feedback.

OldSmoke

That would be '1080/25P FH' right?
See Page 25 - HXR NX5 Manual
http://www.sony.nl/pro/support/attachment/1237485706131/1237485605281/operationmanual.pdf

However if I set it to 1080/25P FH the monitor displays jittery image like with 24fps.
50i is always as smooth as silk FPS wise. But I'll do some comparison test.

Why is that shutter rule only applicable for film cameras?

K-Decisive

Wouldn't shooting 90 degrees mean using the pan crop tool in Vegas to rotate the image?
In Vegas I have noticed that ANY change I make using the pan crop decrease the quality of the image/ pixelate it.
So I try to avoid using the pan crop tool In Vegas



H264 is the only internal codec available in the HXR NX5, I can however use an external recorder like the Atomos to record to Cineform e.t.c using the SDI 10 bit output.

But I must say that looking at many comparison images like the ones below, I am not convinced enough to take that extra step of adding the external recorder. I haven't come across noticeable grading limitations either. Somehow I like the look of the AVCHD/H264 coming out of my cam :- ).

AVCHD 4:2:0 vs Prores 4:2:2.
From blog: http://illuma.blogspot.nl/2013/08/c100-avchd-versus-atomos-samura-prores.html

Img


Comparison Cineform VS H264
Link http://s1117.photobucket.com/user/tonytony87/media/Cineform_Compare_zpsa781d093.png.html

VMP
K-Decisive wrote on 6/20/2016, 11:29 AM
sorry, by 90 degree shutter I mean 1/4 frame time. I have a BMCC, which uses 'film terminology instead of fractions of a second. For 25P that would be 1/100 second like you have. thx

edit: it looks like there's something funky going on with the recorder or maybe the output from the camera ( is interlaced). Normally cineform is a great codec.
OldSmoke wrote on 6/20/2016, 12:05 PM
VMP
Try 1280x720 50p.

Proud owner of Sony Vegas Pro 7, 8, 9, 10, 11, 12 & 13 and now Magix VP15&16.

System Spec.:
Motherboard: ASUS X299 Prime-A

Ram: G.Skill 4x8GB DDR4 2666 XMP

CPU: i7-9800x @ 4.6GHz (custom water cooling system)
GPU: 1x AMD Vega Pro Frontier Edition (water cooled)
Hard drives: System Samsung 970Pro NVME, AV-Projects 1TB (4x Intel P7600 512GB VROC), 4x 2.5" Hotswap bays, 1x 3.5" Hotswap Bay, 1x LG BluRay Burner

PSU: Corsair 1200W
Monitor: 2x Dell Ultrasharp U2713HM (2560x1440)

VMP wrote on 6/20/2016, 12:18 PM
K-Decisive,

Ah ok, yes I have in the past (and heard others doing it) turned the camera to capture vertical objects get better resolution.

That image comparisson is from a blog, I didn't do the test: http://illuma.blogspot.nl/2013/08/c100-avchd-versus-atomos-samura-prores.html

VMP
VMP wrote on 6/20/2016, 12:19 PM
OldSmoke, but that's less resolution than full HD, the camera can shoot 1920x1080.

VMP
OldSmoke wrote on 6/20/2016, 12:30 PM
The HXR-NX5 can only interlaced in 1920x1080 which can cause jagged edges which in turn are not desired for keying. Put it can Shoot 1280x720 at 50p which in many cases is superior and you won't notice the image difference. Give it a try. Use 1/50 shutter for a start to preserve light.

Proud owner of Sony Vegas Pro 7, 8, 9, 10, 11, 12 & 13 and now Magix VP15&16.

System Spec.:
Motherboard: ASUS X299 Prime-A

Ram: G.Skill 4x8GB DDR4 2666 XMP

CPU: i7-9800x @ 4.6GHz (custom water cooling system)
GPU: 1x AMD Vega Pro Frontier Edition (water cooled)
Hard drives: System Samsung 970Pro NVME, AV-Projects 1TB (4x Intel P7600 512GB VROC), 4x 2.5" Hotswap bays, 1x 3.5" Hotswap Bay, 1x LG BluRay Burner

PSU: Corsair 1200W
Monitor: 2x Dell Ultrasharp U2713HM (2560x1440)

VMP wrote on 6/20/2016, 2:09 PM
OldSmoke,

This is an image from page 25 of the manual mentioned above:

That highlighted setting is FX 1080P, Progressive 1920x1080.

Right?

VMP
OldSmoke wrote on 6/20/2016, 3:39 PM
VMP

Correct. 1080 25p but only 1080i 50fps. Since you don't like the look of 25p,
(However if I set it to 1080/25P FH the monitor displays jittery image like with 24fps.) I suggested to go for 720 at 50p which is full progressive 50 frames a second, not interlaced.

Also, what is your final delivery format and frame rate?

Proud owner of Sony Vegas Pro 7, 8, 9, 10, 11, 12 & 13 and now Magix VP15&16.

System Spec.:
Motherboard: ASUS X299 Prime-A

Ram: G.Skill 4x8GB DDR4 2666 XMP

CPU: i7-9800x @ 4.6GHz (custom water cooling system)
GPU: 1x AMD Vega Pro Frontier Edition (water cooled)
Hard drives: System Samsung 970Pro NVME, AV-Projects 1TB (4x Intel P7600 512GB VROC), 4x 2.5" Hotswap bays, 1x 3.5" Hotswap Bay, 1x LG BluRay Burner

PSU: Corsair 1200W
Monitor: 2x Dell Ultrasharp U2713HM (2560x1440)

VMP wrote on 6/20/2016, 4:22 PM
Ok thanks :-).

The final delivery will be Bluray's, VOD and DVD's if required.

VMP
OldSmoke wrote on 6/20/2016, 5:00 PM
So which frame rate do you deliver on BluRay? 24p, 50i or 50p?

Proud owner of Sony Vegas Pro 7, 8, 9, 10, 11, 12 & 13 and now Magix VP15&16.

System Spec.:
Motherboard: ASUS X299 Prime-A

Ram: G.Skill 4x8GB DDR4 2666 XMP

CPU: i7-9800x @ 4.6GHz (custom water cooling system)
GPU: 1x AMD Vega Pro Frontier Edition (water cooled)
Hard drives: System Samsung 970Pro NVME, AV-Projects 1TB (4x Intel P7600 512GB VROC), 4x 2.5" Hotswap bays, 1x 3.5" Hotswap Bay, 1x LG BluRay Burner

PSU: Corsair 1200W
Monitor: 2x Dell Ultrasharp U2713HM (2560x1440)

VMP wrote on 6/20/2016, 5:49 PM

I haven't made many BluRays yet but I was thinkig 50i.
Is there a widely compatible Bluray format, which is compatible outside the PAL world too?

VMP
OldSmoke wrote on 6/20/2016, 7:07 PM
Almost all PAL players will play a NTSC disc but almost no NTSC player will a PAL disc. That's a fact but don't ask me why.

I do mostly sort events, fast motion, I only supply BD in 1280x720 60p. 24p is awful and 1080 60i is just not as smooth as 720 60p. Meaning it really depends what your contents is, 24p may look very good if there is little to no motion or you apply motion blur where necessary. IN my opinion, progressive will always look better then interlaced. You could also try and render 1080 50i to 720 50p, Vegas does an excellent job converting it.
But since your majority is VDO or DVD, I would recommend shooting in 720 50p since you don't like the look of 25p. Vegas does a much better job converting from 720 50p to 480i for DVD then from 1080 50i.

Proud owner of Sony Vegas Pro 7, 8, 9, 10, 11, 12 & 13 and now Magix VP15&16.

System Spec.:
Motherboard: ASUS X299 Prime-A

Ram: G.Skill 4x8GB DDR4 2666 XMP

CPU: i7-9800x @ 4.6GHz (custom water cooling system)
GPU: 1x AMD Vega Pro Frontier Edition (water cooled)
Hard drives: System Samsung 970Pro NVME, AV-Projects 1TB (4x Intel P7600 512GB VROC), 4x 2.5" Hotswap bays, 1x 3.5" Hotswap Bay, 1x LG BluRay Burner

PSU: Corsair 1200W
Monitor: 2x Dell Ultrasharp U2713HM (2560x1440)

VMP wrote on 6/21/2016, 4:00 AM


Thanks OldSmoke!

VMP