Background Separation

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Good to know! Current set up is a ad200 pro, tt350 and large reflector
 
This was a speedlight attached to the curtain pole
 

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acrobatic_Citron said:
View attachment 375115

Hello, As you can see my hair is blending nicely into the black background. How best to seperate my head from the black background. Should I illuminate the back of myself or some light on the background. I'd like to keep it black if possible and this is in my flat so I may be limited by the space to achieve what I want. The background is the lencarta double sided foldeable
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well with a small amount of Post-processing you can easily separate yourself from the background even with the jpg I can get it done so with the raw it will be easy.
 
With this image/situation all you really needed to do is bring the exposure up a bit... as it is it's all a bit flat/grey/under IMO; except maybe the hand (which means the light is a bit too low/forward).

Since the BG is black and seems to be doing a good job of absorbing the light, you can probably add a fair bit more exposure on the subject w/o making it grey... If you add exposure by adding more light/power and it does affect the BG, just add a little more distance to it (if possible). But IDT you even really needed to do that, just change the camera settings...

Or as Chaz said, a quick/easy edit:
Untitled-1.jpg
 
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Awesome thanks! Yeah hand is def a hot spot. my xt30 doesn’t tether so I forget to look at the images in Play mode. i also shoot on film so tips to get right in camera help too
 
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acrobatic_Citron said:
Awesome thanks! Yeah hand is def a hot spot. my xt30 doesn’t tether so I forget to look at the images in Play mode. i also shoot on film so tips to get right in camera help too
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A lot to unpack here, and it’s a long time since I shot any film, but id imagine there’s plenty in that exposure to both drop the exposure on the hand and lift the hair.

I’d still rather do most of the work in camera though (I tend to step back from ‘right in camera’), and it just occurred to me that a small silver reflector could make enough difference to separate the hair too.

As always there’s more than one way to do things.
 
To avoid a new thread could I ask if you use two lights as your key light and how you mount them? Economies of scale means its much cheaper to buy 2 400w godox than 1 800w and having two would also give lots more flexiblity I assume.
Id like enough light to cover 4x5 at f22 (ideally with iso 100/125, foma, fp4) with 120cm softbox so trying to guage how much power I need to future proof myself, cheers
 
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Good question, I’d have to do some maths on the power settings. The f stop and iso are both miles away from my digital FF usage so it’s hard to comprehend. *

But I’ll clarify the term ‘key light’. It’s the main light source, any other lights aren’t the ‘key’.
The key light is your ‘sun’ and there’s only one of them.

* just done some quick mental maths and 400 might not be quite enough for f22 at 100 - but someone else might be able to test
 
Awesome thanks! Have you ever got two suns and put them on one stand for one mega sun? :D
 
In shots like this a silver reflector is often enough. Angle it to pick up some of the key and bounce it back as a hair light. You might need to tweak the key light position a little to deliberate ly light the reflector. The effect is subtle but I think that's what you want here.
 
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Phil V said:
* just done some quick mental maths and 400 might not be quite enough for f22 at 100 - but someone else might be able to test
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400w in a typical softbox should get real close to f/11 from about 1m... of course there's too many variables to say for certain.
acrobatic_Citron said:
Have you ever got two suns and put them on one stand for one mega sun?
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You can place two rectangular softboxes side by side to make a larger square (light a larger area). Or for more power you can place two heads inside a single softbox (e.g. Godox AD-B2), use multiple heads to light a single scrim, or point multiple softboxes at the same spot. The problem with using multiple modifiers as a single key is that it can create odd catchlights.
 
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2 square of course! Heres me thinking in Octos all the time. Just got a great deal on a Godox DP800II previous generatuon model but was £180!
 
acrobatic_Citron said:
Just got a great deal on a Godox DP800II previous generatuon model but was £180!
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Nice.
That strobe has a GN of 88m at ISO 100; 88 ÷ f/22 = 4m. Use a modifier that costs you 2 stops of light and you're down to 1m at f/22 (the size of the softbox doesn't much matter)... Not sure why you would be wanting to use f/22 though; are you shooting large format (4x5 film)?
 
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sk66 said:
Nice.
That strobe has a GN of 88m at ISO 100; 88 ÷ f/22 = 4m. Use a modifier that costs you 2 stops of light and you're down to 1m at f/22 (the size of the softbox doesn't much matter)... Not sure why you would be wanting to use f/22 though; are you shooting large format (4x5 film)?
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Yep I have a large format 4x5 cam and would rather purchase the correct light for everything now rather than buy and extra later
 
acrobatic_Citron said:
Yep I have a large format 4x5 cam and would rather purchase the correct light for everything now rather than buy and extra later
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f/45 is more normal for 4x5, so you're going to need a pretty powerful flash . . .
 
Garry Edwards said:
f/45 is more normal for 4x5, so you're going to need a pretty powerful flash . . .
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Even for portraits? My understanding is the "crop" factor for 4x5 is 0.3ish so f22 would be close enough to f8 which would be enough DOF for me
 
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acrobatic_Citron said:
Even for portraits? My understanding is the "crop" factor for 4x5 is 0.3ish so f22 would be close enough to f8 which would be enough DOF for me
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For a single person portrait I’d be happy with a lot wider aperture than f8.
 
Yeah f16 (5.6) in 4x5 is definitely an option then the model having to stay completely still becomes more important so using f22 gives them more room and also the lenses are designed for us at f16 and up
 
acrobatic_Citron said:
Even for portraits? My understanding is the "crop" factor for 4x5 is 0.3ish so f22 would be close enough to f8 which would be enough DOF for me
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Crop factor . . . it depends what you're comparing it to. An APS-size sensor has an area of about 330sq mm, full frame is 864, 6 x 7cm is 4200 and 5"x4" is 12827

Depth of field . . . Assuming a 210mm lens on a 5x4, the theoretical dof at a distance of 1m is just 6.9cm, or 31.4cm at 2m it is 31.4cm, which may be enough for your needs, but that depends on what you're trying to achieve. https://www.cambridgeincolour.com/tutorials/dof-calculator.htm

Bear in mind that accurate focussing isn't easy with 5x4, looking at a dim image on a ground glass screen.
acrobatic_Citron said:
Yeah f16 (5.6) in 4x5 is definitely an option then the model having to stay completely still becomes more important so using f22 gives them more room and also the lenses are designed for us at f16 and up
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I don't see the relevance of the model having to stay completely still, the flash will freeze any normal movement.
 
Garry Edwards said:
I don't see the relevance of the model having to stay completely still, the flash will freeze any normal movement.
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As dof is so shallow once Ive focused I don't want them moving their eye out of focus simply by hunching - although can always employ the string techinique. the 2m DOF looks good, I look forward to testing the composition to see what working subject distance Id want. Yeah gg focusing can be a pain but the room lights , dark cloth and also a teeny tiny LED they can hold to their face makes things much easier
 
Phil V said:
For a single person portrait I’d be happy with a lot wider aperture than f8.
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He's shooting on 5"x4". Some of the lenses used open up to f/8 or even f/6.3, but this is for focussing only. Quality below f/16 or f/22 is crap, and f/45 or f/64 is normal.
 
Garry Edwards said:
He's shooting on 5"x4". Some of the lenses used open up to f/8 or even f/6.3, but this is for focussing only. Quality below f/16 or f/22 is crap, and f/45 or f/64 is normal.
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I’d meant wider than f/22 (f8 equiv - not my maths)
 
I know you've all been waiting with ancipation

The 800DPII arrived, wow lighting starts to get heavy - glad I bought the lencarta heavy duty stand

At full power, 100ISO , 120 Lencarta soft box , double diffused in a 45/45 position I measured f22 at 100 ISO and f45 at 400 ISO

The soft box diffuser was about 120 cm from my face

So 400 iso is the way forward as itll allow for the bellow extension when I use it for portraits, thanks for all the help guys!
 
jlafferty said:
Wow, did it right! :) I’m envious.
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haha- i heard too many quality control issues with the Intrepid and the latest version was not out at the time. The chamonix is such a beatifully crafted piece , even if I stopped shooting I'd have it on the shelf as an ornament
I've thought about dabbling in 8x10 and if I do I will probably go Intrepid if buying new, the jump from 4x5 to 8x10 everywhere else is very expensive
 
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