Making a White Backdrop

I've been doing a lot of reading on this and the following thread brought up some questions.

https://photography-on-the.net/forum/showthre​ad.php?t=747171

TMR Design wrote in post #8579061
That solution is to take a reflective reading from your background. By taking reflective readings there is now a constant that isn't there with incident readings. A reflective reading that is 4 stops more than your incident subject exposure will render as pure white. Never Fail! If you're shooting your subject at f/8 incident then all you have to do is make sure that you're evenly lighting your background so that you're reading f/32 reflective. If you're shooting at f/4 incident then your background needs to be f/16 reflective. It always works.

1) How exactly do you take a reflective reading?

TMR Design wrote in post #8579061
There's quite a bit of light returning from the background to the subject and it's wrapping. If there's wrap then there's also a lot of light in the subject area that is causing the loss of contrast and potential lens flare.

Use your light meter intelligently and use a combination of incident and reflective metering to nail your subject and background exposures. Background exposure is equally as important as subject exposure. You don't want to clip your highlights on your subject so why would you let them clip on the background?

2) I understand wrapping. Is clipping the same thing, or is either more/less pronounced?

3) Is there any way to do this without a light meter?

I imagine that to get it right it'll take experimentation, but I find most things I do hold true to that. Basic knowledge is still a requirement, and I think that's what I need to get started right.

Thanks for any comments!

Reflective is what you do in camera vs incident, where you meter from the subject position.

Wrapping is basically light flair. it is not clipping but often clipping is a result. It is just excess light to the point it washes out color/detail on the subject. Clipping is simply too much light to record detail, however it is generated.

Yes it can be done without a light meter. It is known as chimping. Shoot a image. look at it on the camera, adjust a light, shoot another, look at it, adjust aperature, shoot another, look at it , adjust the light again, shoot another, look again, adjust again..... you get the point. Even a cheep light meter will save you time. If you are going to do something like this ofter, they are well worth the money.

Muuraija wrote in post #8579876
I've been doing a lot of reading on this and the following thread brought up some questions.

https://photography-on-the.net/forum/showthre​ad.php?t=747171



1) How exactly do you take a reflective reading?



2) I understand wrapping. Is clipping the same thing, or is either more/less pronounced?

3) Is there any way to do this without a light meter?

I imagine that to get it right it'll take experimentation, but I find most things I do hold true to that. Basic knowledge is still a requirement, and I think that's what I need to get started right.

Thanks for any comments!

Hi Muuraija,

You can take reflective readings two ways. One is with a handheld light meter. Light meters give you the ability to take incident readings and reflective readings. When taking reflective readings you want to use a spot metering mode if available and if not then you want to make sure that you get close to the background and meter a small area. A light meter without spot metering such as the Sekonic L-358 is still measuring 54 degrees so if you're too far from the background or have the meter oriented incorrectly you'll be metering too large an area and throwing off your readings.

If you're using the reflective spot metering mode of a camera then make sure the area of the viewfinder used for spot metering is completely covering the area you want to meter and you still want to get close and narrow that area as much as possible.

The reason you don't want too large an area is because if you're metering the entire white background and have areas with gradients or that are less than pure white then those areas will affect the reading. When I use a handheld light meter to spot meter the background I meter the center and then take readings on the sides and corners to ensure even lighting.

Wrap is when light comes back to the subject area and creates highlights on the subject that are not being created by the subject area lighting. On women with long hair you don't tend to see it as much but when they have short hair or you're shooting men with short hair then you'll tend to see it on the neck and cheeks, and if their ears are exposed you'll see it on the ears. With a woman wearing a sleeveless top or a skirt you'll also see it appearing on the arms and legs and it can almost look like edge lighting but out of control edge lighting and usually too hot to be confused with an edge light.

Wrap will occur when there is so much light bouncing off your background and returning to the subject area. Most often you can reduce or eliminate wrap by pulling the subject further away from the background but if you've ever experimented with this you'll see that if you just obliterate the background with light then eliminating the wrap can mean that you have to have your subject 15 or 20 feet from the background. This is why it's important to have the correct amount of light on the background.

The last thing you want is to be bullied around by the light. You want to be in control of the light and not the other way around.

Clipping is when you're overexposed (or underexposed) to the point of exceeding what can be displayed or captured by the camera's sensor. In the case of white clipping it's extreme overexposure. If you're looking at the histogram you'd see it slamming up against the right side.

You can do this without a light meter. It's not impossible. But the light meter really simplifies things and if this is something you have to do on a regular basis or in different locations and scenarios then the light meter will prove to be invaluable and you'll kick yourself for not getting one sooner.

You can experiment to find out where pure white is actually occurring by taking a shot of your white background with the lighting you'll be using and then open that image in a raw editor. Use the eyedropper or equivalent tool to look at the values at various parts of the shot. This will tell you if you're lighting is even and will tell you how close you are to pure white. If you've got a center hot and muddy gradations on the edge or corner then you need to even out the lighting. Once you have even lighting then you can increase or decrease output for the correct level. Once you find the level that is just under pure white (255 in Photoshop) then slowly increase the level until all 3 channels (RGB) are at or just exceed 255. That's pure white and any more light is clipping and only hurting the shot.

This is my all time favourite online tutorial. It has 5 full pages that cover everything from layout, to metering, to post.

http://www.zarias.com/​?p=71

Muuraija wrote in post #8579876
I've been doing a lot of reading on this and the following thread brought up some questions.

https://photography-on-the.net/forum/showthre​ad.php?t=747171



1) How exactly do you take a reflective reading?



2) I understand wrapping. Is clipping the same thing, or is either more/less pronounced?

3) Is there any way to do this without a light meter?

I imagine that to get it right it'll take experimentation, but I find most things I do hold true to that. Basic knowledge is still a requirement, and I think that's what I need to get started right.

Thanks for any comments!

The metering section has a lot to be desired.

The metering, like everything else on that tutorial, is simple, yet VERY effective. That's exactly why I like it. I've people try to explain complicated metering with pages and pages, and don't get nearly the same results.

TMR Design wrote in post #8583006
A light meter without spot metering such as the Sekonic L-358 is still measuring 54 degrees so if you're too far from the background or have the meter oriented incorrectly you'll be metering too large an area and throwing off your readings.

I didn't know there was such a thing.

(Spot metering on a light meter. I guess I made the assumption that raising and lowering the dome would do. Isolate the light source.)

I learned something today...

-Mario

drisley wrote in post #8584085
The metering, like everything else on that tutorial, is simple, yet VERY effective. That's exactly why I like it. I've people try to explain complicated metering with pages and pages, and don't get nearly the same results.

Unfortunately drisley, generically recommending 1.5 or 2 stops above subject exposure is effective because it's too much light. That's why it works and it doesn't teach photographers how to evenly light a background. Anyone can throw light at a white background and render it white when the amount of light is far too much.

Zack openly admits that he is not a technical guy and he is demonstrating what works for him but not really teaching anything about how he arrived at those values. So when people read and follow the tutorial they are not learning anything other than how to follow someone else's method that works but it's not teaching the real technique that should be learned.

As I mentioned in the thread that was linked to, I do like Zack and I respect him as a photographer, but if you're going to tell someone to meter 1.5 or 2 stops over subject exposure you should know why and understand what you're doing. Additionally there is a big difference between 1.5 and 2 stops. One might be rendering white while the other is clipping.

Metering and setting levels shouldn't be so random and generic and Zack says nothing about starting with pure white. If I have a background that is not as white as the one Zack uses then my levels will be different.

If you're picking up a light meter then why take incident readings and have no idea of how much light needs to fall on a background to render it white when you can take a reflective reading and know exactly how much light needs to reflect from that background to make it pure white. One way is guessing and the other is not.

I don't know why people fight this when it's painfully obvious.

m3rdpwr wrote in post #8584145
I didn't know there was such a thing.

(Spot metering on a light meter. I guess I made the assumption that raising and lowering the dome would do. Isolate the light source.)

I learned something today...

-Mario

The L-358 will take reflective readings but with 54 degree coverage. You can add a spot metering accessory that will give you 5 degree coverage. The L-758DR has a built in 1 degree spot meter.

I think Robert has hit the nail right on the head. Its so important to have the light spread evenly across the background and say you subject is f/8 the background should be 1 1/2-2 stops up from that and EVEN across it and the only effective way to know that is a reflective meter reading.If you do it right you can get no more than a half stop up and down and across the entire B/G. If I have the room I like to shoot the light through the back side with two lights. That was you won't have any unwanted light spilling on the subject. So if I do a flash/incident of the subject and it reads f/8 then I would want the B/G to read 11.5 or 16 flash/reflective. That would put the subject at zone V and the white should be zone VII which is 2 stops up which is white.

I've read books like Scott Smith's wonderful "Studio Lighting Made Simple", I think you did too TMR, then went on to read other more advanced lighting books, and tutorials, until I got a good understanding of everything technically. However, when time came to shoot, my results were less than impressive.

So, I really like the KISS principle from the link I showed. It's affordable, and easy to understand, and I get much better results now than I ever did.

I guess it's good, perhaps, necessary to know the technical details, but some people can go overboard. I know many photogs that know every in and out about lighting a scene technically correct, own thousands of dollars worth of strobes, but their real-world results are often uninspiring. Anyway, I just thought I would add that tutorial to the mix, since it's long been my favourite.

Then again, I re-read the original post, and yes, the info TMR provided is way more on topic and helpful I think.

drisley wrote in post #8583927
This is my all time favourite online tutorial. It has 5 full pages that cover everything from layout, to metering, to post.

http://www.zarias.com/​?p=71

Wow, thank you for this link!!!!

drisley wrote in post #8584284
I guess it's good, perhaps, necessary to know the technical details, but some people can go overboard. I know many photogs that know every in and out about lighting a scene technically correct, own thousands of dollars worth of strobes, but their real-world results are often uninspiring.

Nothing is more uninspiring than a poorly crafted image.

Gentleman Villain wrote in post #8584848
Nothing is more uninspiring than a poorly crafted image.

Now that is the truth.

Thank you everyone for your thoughts. Now I have have to try and make what I'm learning into something like art. Wish me luck!