Advice please white bg

[Hell on earth]

Hi, so I need some sensible advice please
This is as shot 125. f9
bg lit all round at f11 on vinyl white bg

Could not go any brighter as would (has a little) blow the the white on the costume and the red out of gamut
Painting the bg and shadows out, makes it look like a cut-out
See photos here http://www.talkphotography.co.uk/threads/little-keira-another-added.520740/

So what to do ? to brighten the bg and not have it looking like a cut out

View attachment 2173

H

 

[boyfalldown]

increase the power on the background a little, and bring the boy forward from it as well. Don't increase it so much you start to get light wrapping the subject though, but bringing him forward will help with this. Bringing the white & highlight slider up in LR as part of your PP will help with tiding the background after. If you have to use a brush or cut out afterwards then increasing the feather on the brush to between 5-10pxls will help get rid of the cutout look

 

[Hell on earth]

Ok good advice but I'm limited to space

I tried the sliders but they blow the reds out with the white fur :shrug:

H

 

[boyfalldown]

If you're really limited a hi lite is possibly the answer, but you'll need to clean the floor up in pp

 

[Hell on earth]

If you're really limited a hi lite is possibly the answer, but you'll need to clean the floor up in pp

Yes, I'm on the look out for one, this red on the gamut is and would still be a problem other than making it darker hmm


Thanks
H

 

[TG.]

I tried the sliders but they blow the reds out with the white fur :shrug:

H

Using a layer mask could solve this, that way the red stays intact, and you just adjust the white to what you want.

 

[sk66]

Looks like you're about 1/2-1 stop shy. Reduce the power of the main and open up the aperture to compensate...

Looks like you might need to flag the BG lights off of the kid...it's going to be hard keeping the white trim from blending into the BG.

 

[Hell on earth]

Using a layer mask could solve this, that way the red stays intact, and you just adjust the white to what you want.

I'm not sure as to how to do that ?
H

 

[Hell on earth]

Looks like you're about 1/2-1 stop shy. Reduce the power of the main and open up the aperture to compensate...

Looks like you might need to flag the BG lights off of the kid...it's going to be hard keeping the white trim from blending into the BG.

I've often read on here and elsewhere, not to use more than a stop between the bg and the main, had problems before with the bg light hitting the subject and lens flair, flagging would help but would have to expand the bg in post so then more blending, not ideal
The white trim was also a reason not to go to high on the bg lights
As boyfalldown said use a hi-lite but they are not cheap and you still have a problem cleaning up the floor Hmm

H

 

[Pookeyhead]

I've often read on here and elsewhere, not to use more than a stop between the bg and the main, had problems before with the bg light hitting the subject and lens flair, flagging would help but would have to expand the bg in post so then more blending, not ideal
The white trim was also a reason not to go to high on the bg lights
As boyfalldown said use a hi-lite but they are not cheap and you still have a problem cleaning up the floor Hmm

H

There's not really much to be done if you don't have room. The only ideal way is to separate background lights from subject lights.

Flagging aint a big deal, even if you end up with stuff in the frame, as the background should be white.... just clone them out.

yes.. BG shouldn't be more than one stop more, or it can flare, lower contrast, or wrap around the subject. If lit properly, there's no reason why the background needs to be metered any brighter than the subject lights. After all, white things in a well exposed photo should be white. People only like to blast it out because they're too lazy to retouch. White objects in a photo should NOT be R255, G255, B255... they should still have detail and texture.

 

[Hell on earth]

There's not really much to be done if you don't have room. The only ideal way is to separate background lights from subject lights.

Flagging aint a big deal, even if you end up with stuff in the frame, as the background should be white.... just clone them out.

yes.. BG shouldn't be more than one stop more, or it can flare, lower contrast, or wrap around the subject. If lit properly, there's no reason why the background needs to be metered any brighter than the subject lights. After all, white things in a well exposed photo should be white. People only like to blast it out because they're too lazy to retouch. White objects in a photo should NOT be R255, G255, B255... they should still have detail and texture.

Thanks
H

 

[sk66]

It doesn't really matter what you metered the BG at, it's not *at* a stop above the subject... if anything it's slightly less than the subject. I'm suggesting bringing the lighting *down* to get your ratio, not hit the BG harder; there *is* a difference....Turning the levels down in this case takes advantage of the inverse square law for the BG as a light source (to the subject/camera). You could turn the main light off and it's not going to change the character/effect of the BG lights significantly.

In fact, maybe you should turn off the main so you can see exactly what the BG lights are doing (don't change your exposure). Good lighting is built up in "layers" with each layer contributing a specific part... In this case, due to limited space, each "layer" isn't very "specific" in what it's doing. The main is probably helping to light the BG and the BG/BG lights are lighting the subject and throwing shadows. Lowering the power levels of the lights (and compensating w/ camera exposure/ lighting distances) can help make them more "specific."

Flare, contrast, wrap issues, are not caused by the lighting ratio as such. It's caused by too hot a light source (the BG) from too close (to the subject/camera).... it's the inverse square thing again... It's usually caused by too small of lighting (not enough spread) being used to where the center has to be driven well above white for the edges of the BG to be white... it's the "extra" from the center that causes the issues. The camera doesn't "see" anything beyond white *at the BG*, but it sees it coming back at it...

I hope this makes sense...

 

[Hell on earth]

It doesn't really matter what you metered the BG at, it's not *at* a stop above the subject... if anything it's slightly less than the subject. I'm suggesting bringing the lighting *down* to get your ratio, not hit the BG harder; there *is* a difference....Turning the levels down in this case takes advantage of the inverse square law for the BG as a light source (to the subject/camera). You could turn the main light off and it's not going to change the character/effect of the BG lights significantly.

In fact, maybe you should turn off the main so you can see exactly what the BG lights are doing (don't change your exposure). Good lighting is built up in "layers" with each layer contributing a specific part... In this case, due to limited space, each "layer" isn't very "specific" in what it's doing. The main is probably helping to light the BG and the BG/BG lights are lighting the subject and throwing shadows. Lowering the power levels of the lights (and compensating w/ camera exposure/ lighting distances) can help make them more "specific."

Flare, contrast, wrap issues, are not caused by the lighting ratio as such. It's caused by too hot a light source (the BG) from too close (to the subject/camera).... it's the inverse square thing again... It's usually caused by too small of lighting (not enough spread) being used to where the center has to be driven well above white for the edges of the BG to be white... it's the "extra" from the center that causes the issues. The camera doesn't "see" anything beyond white *at the BG*, but it sees it coming back at it...

I hope this makes sense...

I metered both, bg at f11 subject at f9. ok not a full stop but the bg was above the subject not less, they were metered separately, bg with the main off and so on
If the main were adding to the bg, would that have in fact, made the bg brighter ? but I don't think it did due to fall off
The lighting looks fairly even (taking away the shadows where the floor rippled) which is what I find strange

H

 

[sk66]

How did you meter the BG? I would spot meter it from the camera's position. If you did an incident reading, that could be the issue... because the lights are hitting the BG at an angle the light isn't all going back to the camera. But if spot metering remember it's going to assume the BG is gray.
Yes, the main should make the BG brighter if it's spilling onto it, and I'm pretty certain it is... If the lights are 4ft from the subject, and the BG another 2ft away (1.6ft to be more precise), you would have 1 stop of falloff (it works just like aperture stops, just make it ft instead of f/) but it would still add something.

 

[Richard King]

WHyy do you want a white background? Infact this chap would have looked better with some things of interest in the shot..

 

[Hell on earth]

How did you meter the BG? I would spot meter it from the camera's position. If you did an incident reading, that could be the issue... because the lights are hitting the BG at an angle the light isn't all going back to the camera. But if spot metering remember it's going to assume the BG is gray.
Yes, the main should make the BG brighter if it's spilling onto it, and I'm pretty certain it is... If the lights are 4ft from the subject, and the BG another 2ft away (1.6ft to be more precise), you would have 1 stop of falloff (it works just like aperture stops, just make it ft instead of f/) but it would still add something.

L/m to the Camera from the bg and from subject

 

[Hell on earth]

Why do you want a white background? Infact this chap would have looked better with some things of interest in the shot..

Well yes a bit boring but thats what they wanted, I did say it's a little boring but ...

I did not have any props, this was an after shot a few days after I did a family shoot, where the lady just came to me on the off chance to get the kid in the outfit

H

 

[sk66]

L/m to the Camera from the bg and from subject

An incident reading then... with the dome on? I honestly suspect that's the problem (because the BG lights are on a shallow angle due to not enough space between the subject/BG).
Metering the BG should be a reflectance reading, particularly in this situation. You could just put the incident meter close to the BG and pointed at it, but the dome might make it read a little higher.
The reason the BG should be a reflectance reading is because it's a flat surface. The difference being that a subject (that's not flat) will reflect at least some of the light directly back to the camera so an incidence reading works. If a flat surface is lit more directly an incidence reading can also work.

 

[Hell on earth]

An incident reading then... with the dome on? I honestly suspect that's the problem (because the BG lights are on a shallow angle due to not enough space between the subject/BG).
Metering the BG should be a reflectance reading, particularly in this situation. You could just put the incident meter close to the BG and pointed at it, but the dome might make it read a little higher.
The reason the BG should be a reflectance reading is because it's a flat surface. The difference being that a subject (that's not flat) will reflect at least some of the light directly back to the camera so an incidence reading works. If a flat surface is lit more directly an incidence reading can also work.

Thanks for that, I've never seen or read that before
Just the other day on Creativelive there was a studio lighting show on and they were taking the light reading the same way I do

Garry Edwards one of the members on here does the same here

 

[Phil V]

Thanks for that, I've never seen or read that before
Just the other day on Creativelive there was a studio lighting show on and they were taking the light reading the same way I do

Garry Edwards one of the members on here does the same here

Presumably though, those readings were done in plenty of space, whereas the advice above is to get round the incorrect meter reading due to the lack of space. You can see that there's no way the background is getting as much light as the subject? You appear to think that because your meter says it was getting plenty of light that it must have been, clearly it isn't, which is why you asked the question.

The easiest way to measure your background lights is to shoot and check your LCD with blinkies turned on, with a little practice and note taking you ought to be shooting this setup without taking readings. In expensive studios with camera monkeys the lights and apertures are fixed so the camera monkey only has the picture to worry about.

 

[Hell on earth]

Ok Thanks Phil

H

 

[coldpenguin]

I think unfortunately you are getting just what Gary is saying in the second half of the second film. Your background is too close to the subject (for the position of the lights at least) and you are getting spill from the background onto the subject. You may not have a lot of room, but if your focus can take it, you might be able to strech that child 2' furthet forward and still have it in frame.

As to recovering the photo that is taken, in photoshop (as that is what I have, I am not sure of the other tools), I would create a new adjustment layer, contrast/brightness or levels. Then create a layer mask. Blank everything out on that layer. Then paint in the brightness to the background. Set the values to be large/over exagerated so you can see where you have painted easily, then dial back the values or fill/opaqueness once complete.
Alternatively, for a 'dreamy' look, I use smart select on the foreground item. Then I use contract 10px, feather 20px, then delete/clear (maybe invert first depending on what exactly you have selected).

If you would allow an edit on that photo, it should take 5 minutes to demonstrate.

 

[Hell on earth]

I think unfortunately you are getting just what Gary is saying in the second half of the second film. Your background is too close to the subject (for the position of the lights at least) and you are getting spill from the background onto the subject. You may not have a lot of room, but if your focus can take it, you might be able to strech that child 2' furthet forward and still have it in frame.

As to recovering the photo that is taken, in photoshop (as that is what I have, I am not sure of the other tools), I would create a new adjustment layer, contrast/brightness or levels. Then create a layer mask. Blank everything out on that layer. Then paint in the brightness to the background. Set the values to be large/over exagerated so you can see where you have painted easily, then dial back the values or fill/opaqueness once complete.
Alternatively, for a 'dreamy' look, I use smart select on the foreground item. Then I use contract 10px, feather 20px, then delete/clear (maybe invert first depending on what exactly you have selected).

If you would allow an edit on that photo, it should take 5 minutes to demonstrate.

Thanks yes go edit can you do screen shots of process ?

H

 

[boyfalldown]

Let me know if you want to get rid. This is just a minute in LR and it needs tidying up, especially on the white fur and his boots. There are also adjustments needed still to finish mopping up the BG. An adjustment brush +1 exposure auto masked with 7 pxl feather. Then the following adjustments

exposure +.25
whites +25
highlights +1

 

[Hell on earth]

Let me know if you want to get rid. This is just a minute in LR and it needs tidying up, especially on the white fur and his boots. There are also adjustments needed still to finish mopping up the BG. An adjustment brush +1 exposure auto masked with 7 pxl feather. Then the following adjustments

exposure +.25
whites +25
highlights +1

Thanks for that
I've done it that way before but had the feather much higher, so not doing a very good job of it
Leave it up as may help others

H

 

[sk66]

Quick and dirty..
Duplicated layer and then Image>adj>shadows/highlights to recover detail in suit trim. Invert mask and paint in as desired.
Levels adjustment setting white and black points... I selected some of the lighter shadows as the white point. Mask off areas of suit that blow out.
Second levels adjustment, this time ONLY for the BG and selecting darker shadows as the white point... invert mask and paint in where desired.

I generally use a soft brush with a low flow...

Other's photos by sk66 on Talk Photography

 

[Hell on earth]

Quick and dirty..
Duplicated layer and then Image>adj>shadows/highlights to recover detail in suit trim. Invert mask and paint in as desired.
Levels adjustment setting white and black points... I selected some of the lighter shadows as the white point. Mask off areas of suit that blow out.
Second levels adjustment, this time ONLY for the BG and selecting darker shadows as the white point... invert mask and paint in where desired.

I generally use a soft brush with a low flow...

Other's photos by sk66 on Talk Photography

Great stuff thanks
H

 

[coldpenguin]

All a lot better than my attempt.
First problem I had, was when I put it into photoshop, I ended up with a red cast.
View attachment 2426
No matter which colour profile I assigned.
So first call was to add a new adjustment layer, Layer -> New Adjustment Layer, Levels. I selected Auto, (well, this is only a demo).
View attachment 2427
Next, I did a quick selection using the quick selection tool (similar to the magic wand). (Press W in photoshop 4). I saved the selection, and this is what it looked like. The better your selection, the better the end result, but givin that this is a quick demo, the quick selection is plenty good enough (and is often good enough for anything other than hair or pale yellow/white fluffy stuff).
View attachment 2428
Now use select inverse, and do a Layer -> New Layer. You should end up with a white background, with a transparent child.
Now select, inverse again.
Now, I go to selection -> Modify -> Expand
I used a value of 15 pixels, this is too much for the resolution this photo is currently at, but the exagerated shadow is useful as a demo.
I then used selection -> Modify -> Feather
Select inverse once final time (for some reason, I don't find the contract quite as effective as expand)

Now, create a layer mask on the layer which was just white with a transparent child. Your layer mask should be a black child, with a white background.
View attachment 2429
Not yet quite what you want I guess (the values I used were exagerated to show the effect), although I have printed several images out like this, it works well I think in Acrylic blocks
Now do Layer -> New -> Group
It should put your shadowy layer into a group. Now create a new layer mask for the group. Turn it completely black. Then use the gradient tool (hidden by the fill tool usually), and I selected foreground to background. I clicked about midway through the thigh, going straight up.
This enables some of the white masking, making it look like the floor is dissapearing into the wall.
View attachment 2431
Try to imagine the above picture with only about a third as much 'shadow' behind the child.

 

[coldpenguin]

View attachment 2432
This is what the layers panel should look like, if successful

 

[HoppyUK]

I've only skimmed the thread, so apologies if this has been covered.

Whatever your metering method, the background is not over-exposed. I only use a meter for rough setting up and always set final exposure with reference to the LCD, histogram and blinkies. This is the most accurate way of judging what is actually on the sensor and the blinkies will tell you when the background is over-exposed.

There's no avoiding the fact that pure white backgrounds are difficult, more so in a small working area. As mentioned, a HiLite is probably the best idea, but even then you need to do some careful set up tests, getting the background as even as possible, setting ratios carefully, moderating wrap, controlling flare etc. You'll likely still need to do some cleaning up in post processing.

Blinkies are an invaluable aid, and you should also do some tests there. Blinkies flash on over-exposed and blown areas, but they also flash on areas that are on the brink of blowing. You need to establish by experiment exactly how much headroom you've got above the blinkies threshold. It will probably be around one stop, but varies according to camera, the picture styles pre-sets applied, and post processing regime.

 

[sk66]

I'm not really understanding how a HiLite is easier/better...
I've seen plenty of examples with a ton of wrap/flare using one. I do understand how it might be easier to light more evenly, but no hugely so. Is it just that the light on/from the BG is automatically more controlled so you don't have to?

 

[boyfalldown]

I'm not really understanding how a HiLite is easier/better...
I've seen plenty of examples with a ton of wrap/flare using one. I do understand how it might be easier to light more evenly, but no hugely so. Is it just that the light on/from the BG is automatically more controlled so you don't have to?

You don't need the amount of space with a Hi Lite you do with another white background. Of course if your lights are set with far too much power you'l still get wrap/flare but its a lot easier to set it up properly. Esp in limited space

 

[HoppyUK]

I'm not really understanding how a HiLite is easier/better...
I've seen plenty of examples with a ton of wrap/flare using one. I do understand how it might be easier to light more evenly, but no hugely so. Is it just that the light on/from the BG is automatically more controlled so you don't have to?

Main advantage of Hilites is they can be used in a much smaller space, particularly width, and are easy to light evenly. You still need to control wrap and flare, and in the absence of generous working distance, that has to be done with screens and flags etc. It's certainly not a case of just throwing it up and blasting away.

Edit: crossed post with Hugh

 

[Phil V]

Well I would have said what they said too.

It's not some kind of magic bullet, as it would seem sometimes by the recommendations. However, the amount of space required to light a white background traditionally is huge, both width and background separation. Both those can be done in a much smaller space with a hi lite. I haven't got one btw, but I do have a large space when I use a white bg so I don't need one.

 

[sk66]

Seems to me the separation requirement would (should?) be the same for a given luminance from either method... And what's the minimum width requirement for a single adult; maybe 10ft? Probably less if the BG was lit with modifiers... Or you could backlight a silk if width is an issue (but that cramps the length more).

Is a Hilite any good as a full length softbox? I mean, you can buy a 5ft x 6ft softbox for less money... I'm not saying one way or the other; I haven't used one. But the whole idea seems a bit like a gimmick to me. It makes more sense to me if you were going mobile; strobist style. Then I could see it.

IMHO, there is no substitute for having a suitable studio space if doing studio work...

 

[Phil V]

Seems to me the separation requirement would (should?) be the same for a given luminance from either method... And what's the minimum width requirement for a single adult; maybe 10ft? Probably less if the BG was lit with modifiers... Or you could backlight a silk if width is an issue (but that cramps the length more).

Is a Hilite any good as a full length softbox? I mean, you can buy a 5ft x 6ft softbox for less money... I'm not saying one way or the other; I haven't used one. But the whole idea seems a bit like a gimmick to me. It makes more sense to me if you were going mobile; strobist style. Then I could see it.

IMHO, there is no substitute for having a suitable studio space if doing studio work...

It's not simply a matter of separation, it's light placement. I'm not doing the maths in thread, but if you've got a 3m wide bg, and you're cross lighting it with 2 lights at an angle of 45deg, and you want to avoid any of that light spilling onto your subject, that creates a space requirement that of 3metres plus, most pros would be aiming for 5.

You can mitigate that with specialist bg reflectors and with flagging, but basically the hi lite removes the need for proper studio dimensions for lighting rather than separation. As you say, mostly for mobile or typical home size set ups.

 

[Pookeyhead]

An incident reading then... with the dome on? I honestly suspect that's the problem (because the BG lights are on a shallow angle due to not enough space between the subject/BG).
Metering the BG should be a reflectance reading, particularly in this situation.

Err... no. A reflectance reading off a white background will render the background 16 to 18% grey. Think about it.

Thanks for that, I've never seen or read that before

No... I doubt you have... because it's wrong.

Invacone on (incident) and meter back to camera, just as the guy in the video above is doing.


This is lit the same way the guy in the vid was doing it, which is the way I was taught decades ago, and the way I've been doing it since.... reliably for decades too. This is literally straight off camera, as you can see by the crap on the studio floor.

And another thing: Over-exposing backgrounds. There is absolutely NO need to do this if you meter correctly. Meter for your background, and then use that as the shooting aperture, and meter the subject lights accordingly. Over exposing the background is crap for 2 reasons. 1 - the background starts to make the background behave as a light source, and it will destroy fine detail like hairs etc, and also, if you go too far, the light will start to wrap around the subject... you'll be BACKLIGHTING... or RIM LIGHTING the subject. 2 - white should never be R255, G255, B255..... NOTHING in a well exposed photograph should be. If anything is pure white, then you've over exposed IMO (only specular highlights from shiny things, or street lights in long exposures etc are acceptable as pure white IMO). The shot above is probably around R251, G251, B251 on the background. This is correct. If I printed this with a white border, you could still see where the image ends and teh paper base starts. This is how it should be. A pure white RGB255 background has no detail, and looks bloody awful when printed.

For this reason, making a background white in post process also looks crap (You're photographers, learn how to light!!) it will just be a featureless void. If you wanna argue, then you're also arguing against some pretty big heavy weights, including Ansel Adams here, and I doubt ANY of us in here, no matter how advanced can say they know more about producing a well exposed image that that guy did.

A correct incident reading for your background will always produce perfect results if you know what you're doing (and it's lit evenly). You just need space between your model and the background, and flag off the lights so they don't interfere with one another. The image above is proof of this. It's white... it has not destroyed any fine detail... if you zoom in you can see the texture of the backdrop and it will not be RGB255.

I appreciate that sometimes you don't have the room to separate the model from the background, but with careful flagging, you can still get away with it. Plus, I'd rather have soft, well controlled shadows than have people floating in a sea of RGB255... it just looks rubbish when printed.

 

[sk66]

Of corse a reflectance meter reading is for 18% gray.... I mentioned that and that it needs to read ~ 2 stops above if you want it to be white (because white is ~ 2 stops above gray). An incidence reading is also for 18% gray, but it is subject independent.

 

[Pookeyhead]

Of corse a reflectance meter reading is for 18% gray.... I mentioned that and that it needs to read ~ 2 stops above if you want it to be white (because white is ~ 2 stops above gray). An incidence reading is also for 18% gray, but it is subject independent.

but you said....

An incident reading then... with the dome on? I honestly suspect that's the problem (because the BG lights are on a shallow angle due to not enough space between the subject/BG).
Metering the BG should be a reflectance reading, particularly in this situation.

You suggested a reflected reading, which is not good advice. If the angle of lighting to the background is sharp due to space limitations, then just meter back to the lights, not the camera. The best way to render white as white is to measure the light falling on it with an incident reading. I've shot in hugely tight spaces in such a way, and never, ever had a problem.

I can't think of any good reason to use a reflected reading off a white background.

In fact...if the lights were at an acute angle, and you took an incident reading back to camera, that would far more likely result in over exposure of the background, not the other way around.

 

[HoppyUK]

<snip>

And another thing: Over-exposing backgrounds. There is absolutely NO need to do this if you meter correctly. Meter for your background, and then use that as the shooting aperture, and meter the subject lights accordingly. Over exposing the background is crap for 2 reasons. 1 - the background starts to make the background behave as a light source, and it will destroy fine detail like hairs etc, and also, if you go too far, the light will start to wrap around the subject... you'll be BACKLIGHTING... or RIM LIGHTING the subject. 2 - white should never be R255, G255, B255..... NOTHING in a well exposed photograph should be. If anything is pure white, then you've over exposed IMO (only specular highlights from shiny things, or street lights in long exposures etc are acceptable as pure white IMO). The shot above is probably around R251, G251, B251 on the background. This is correct. If I printed this with a white border, you could still see where the image ends and teh paper base starts. This is how it should be. A pure white RGB255 background has no detail, and looks bloody awful when printed.

For this reason, making a background white in post process also looks crap (You're photographers, learn how to light!!) it will just be a featureless void. If you wanna argue, then you're also arguing against some pretty big heavy weights, including Ansel Adams here, and I doubt ANY of us in here, no matter how advanced can say they know more about producing a well exposed image that that guy did.

A correct incident reading for your background will always produce perfect results if you know what you're doing (and it's lit evenly). You just need space between your model and the background, and flag off the lights so they don't interfere with one another. The image above is proof of this. It's white... it has not destroyed any fine detail... if you zoom in you can see the texture of the backdrop and it will not be RGB255.

I appreciate that sometimes you don't have the room to separate the model from the background, but with careful flagging, you can still get away with it. Plus, I'd rather have soft, well controlled shadows than have people floating in a sea of RGB255... it just looks rubbish when printed.

Agree... but also disagree.

The pictorial effect being discussed is the one that customers demand. Call it the 'Venture look' if you like, but it's pure white, and plenty of wrap is all part of it. What you, or I, or quite a few other respected posters on here might prefer, is to miss the point.

So a small degree of deliberate over-exposure of the background is necessary. And in one sense at least it makes things easier because it's very hard to get perfectly even exposure over the background in a typical small/domestic studio, so the trick is to get it 'just' blown directly behind the main subject, and then clean up the grey bits in post processing. That's a heck of a lot easier to do if it's all 255/255/255.