Announcement

Collapse
No announcement yet.

Completely white background, how to?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Completely white background, how to?

    Hai gais! Lately, I've been doing a lot of shoots requiring a completely white backgrounds...I've been doing fairly well with consistent lighting but 2 hotshoe flashes aren't providing enough power to overexpose the white vinyl backdrops that I use.

    The way that I blow out my white backgrounds is dodging the highlights @ 10-35% opacity with the "preserve tone" unchecked. But when I open up levels and drag my midtones to the right, it still shows detail in the highlights...
    That and sometimes the background can have a color tinge to it and not be completely white. How do I make my backgrounds completely white without using the eraser tool or white paint brush?

  • #2
    Re: Completely white background, how to?

    Two external flashes, at full shot through an umbrella, softbox, or even bounced of large white v-flats are more than sufficient to blowout a background. It's all comparative to your mainlight. I don't know the exact ratio, 5:1 6:1? I have no idea, but raise your aperture drop your key lights, and it'll blow the background out.

    When you say white vinyl background.. is the background material vinyl, like that shiny stuff.. because if it is, your subject will have pretty darn far away from the background so that the light isn't reflected off onto the subject's shoulder.

    Once you've shot it right, simply use a raw converter to find white balance so you don't have any color shifts on the white, and it's probably a good idea to check for chromatic aberration. In photoshop you can manually find white balance by checking with numbers (if you don't know, you can search it).

    Sometimes you mess up, so photoshop is your friend. Create a levels adjustment layer, slide your shadows slider nearly a third of the histogram to the right. Make sure you have a duplicate of the original image and use your dodging tool, set to highlights (if its selected at shadows or midtones, this may be why your highlights aren't being totally blown out), opacity ususally 15 - 10 %, and just over and over trace around your subject. Try to be careful at this point, but if your brush hits the subject then it usually isn't that big of a deal. When done, make sure you delete your levels adjustment layer. Good luck.

    Comment


    • #3
      Re: Completely white background, how to?

      Originally posted by namphoto View Post
      Two external flashes, at full shot through an umbrella, softbox, or even bounced of large white v-flats are more than sufficient to blowout a background. It's all comparative to your mainlight. I don't know the exact ratio, 5:1 6:1? I have no idea, but raise your aperture drop your key lights, and it'll blow the background out.

      When you say white vinyl background.. is the background material vinyl, like that shiny stuff.. because if it is, your subject will have pretty darn far away from the background so that the light isn't reflected off onto the subject's shoulder.

      Once you've shot it right, simply use a raw converter to find white balance so you don't have any color shifts on the white, and it's probably a good idea to check for chromatic aberration. In photoshop you can manually find white balance by checking with numbers (if you don't know, you can search it).

      Sometimes you mess up, so photoshop is your friend. Create a levels adjustment layer, slide your shadows slider nearly a third of the histogram to the right. Make sure you have a duplicate of the original image and use your dodging tool, set to highlights (if its selected at shadows or midtones, this may be why your highlights aren't being totally blown out), opacity ususally 15 - 10 %, and just over and over trace around your subject. Try to be careful at this point, but if your brush hits the subject then it usually isn't that big of a deal. When done, make sure you delete your levels adjustment layer. Good luck.
      Thanks for the reply, I got my wording wrong. Atm, I'm lighting the background with 1 flash and the subject with the other flash thru an umbrella. I suppose I could increase my aperture but I'm usually shooting around f/5.6 and any wider, I'd risk having uneven focused body shots. :s then again I could increase ISO...the vinyl is porous and doesn't reflect much light, so spill isn't really a concern.

      I shot with a custom WB but it wasn't with 18% gray. I'll do a search about the numbers.

      The dodging way you described is exactly what I do but with heavier opacity and with levels adjustment but eliminating midtones to expose the data in the highlights. Yet still there's some artifacting in the shadowy areas that I dodged, I usually notice this when I tilt my screen. It's like spotting dust in my viewfinder

      I don't have much problems with CA, (thanks to L lens ) but I could see how that would add problems when dodging out the BG.


      Thanks for reply!

      I read somewhere you can pinpoint the beginning of the highlights and clip it via curves but I can't seem to find it again... Shoot!

      Comment


      • #4
        Re: Completely white background, how to?

        As Namphoto has already mentioned the ratio is important and an ideal high key setting would be 4 lights, for example if the subject reading is F8 then the two backlights burning the BG should be F11..
        There is a diagram here at:

        http://jerrycentral.com/2008/07/09/h...hting-diagram/

        Another method, easier if you have a sunny window to place the subject in front of it make sure it has net curains or even better a white silk blind to diffuse the light.
        Use fill flash, bump up the ISO and your bg should be burned out.
        Here's an example taken in a living room against a bright window with only fill flash...
        1/60 @ F4.5
        ISO 1600
        I underexposed the original so you can see the window, the covering is a net curtain and it worked...
        Regards,
        Gary...
        Attached Files

        Comment


        • #5
          Re: Completely white background, how to?

          Oh! Thanks for the link Algarve Images. If I'm not mistaken the diagram looks like there's only 3 light sources and a reflector. I'll be ordering some Alienbee's this week so lighting will be a lot more easier to manage.
          Good example picture too! But I don't think commercial photography would benefit from the light bleed :/ or 1600 ISO haha! Actually, that looks pretty clean.

          But since this thread is in the post production section, does anyone know any other alternatives or more efficient ways to correct imbalanced BG lighting?

          Comment


          • #6
            Re: Completely white background, how to?

            For the colour tinge, you could try with a Hue/Saturation Adjustment Layer:
            • pump up saturation to 100% to identify the colour cast/casts
            • Go to the 'guilty' colour/s and decrease the saturation completely and increase luminosity to 100%

            If necessary add a Selective Color Adjustment Layer go to the Whites and decrease the black completely.

            Of course, it would be easier if you could post the problem part of your image...

            Comment


            • #7
              Re: Completely white background, how to?

              Originally posted by Flora View Post
              For the colour tinge, you could try with a Hue/Saturation Adjustment Layer:
              • pump up saturation to 100% to identify the colour cast/casts
              • Go to the 'guilty' colour/s and decrease the saturation completely and increase luminosity to 100%

              If necessary add a Selective Color Adjustment Layer go to the Whites and decrease the black completely.

              Of course, it would be easier if you could post the problem part of your image...
              Thanks for the info! The pictures are on hold by the company I work for but I think I can swing an upload since I took them.

              Comment


              • #8
                Re: Completely white background, how to?

                Here's an unedited, resized and compressed image I took a few days ago for a website.
                When dodging out the highlights and edging into the underexposed areas there's some data left when I adjust my levels. Sometimes when I create marques and hit delete which leaves behind 255/255/255 RGB white, my background is subtly noticeable alongside the white deleted areas. It's not that bad but I'm really anal about pp'ing simple photos like this one.

                You can see (well I can at least @[email protected]) a yellowish tinge artifacting around the left girl if you tilt your screen slightly. Haha, I feel pretty goofy about such little details you can barely see.
                Attached Files
                Last edited by Bro Photo; 03-24-2009, 01:41 PM.

                Comment


                • #9
                  Re: Completely white background, how to?

                  Originally posted by Bro Photo View Post
                  Oh! Thanks for the link Algarve Images. If I'm not mistaken the diagram looks like there's only 3 light sources and a reflector. I'll be ordering some Alienbee's this week so lighting will be a lot more easier to manage.
                  Good example picture too! But I don't think commercial photography would benefit from the light bleed :/ or 1600 ISO haha! Actually, that looks pretty clean.

                  But since this thread is in the post production section, does anyone know any other alternatives or more efficient ways to correct imbalanced BG lighting?
                  Yep,
                  looks like 3 lights and thats good for me too as i've ordered 3 elinchrom's from UK.
                  The D3 is clean up to 1600 and usable at 3,200/6400 for smaller prints, at 800 ISO there is no visible diference from base ISO of 200

                  Comment


                  • #10
                    Re: Completely white background, how to?

                    Hi again,

                    using the Hue/Saturation at 100% saturation on your original you can see the different tinges in your background: yellow, red, magenta etc. and there are also a couple of patches of grey. (Attachment 1)

                    So, even before seeing your corrected version, I also opted for a selection and simply used a Levels Adjustment layer on the selected background.
                    (Attachment 2) from left: original, white background, adjusted luminosity particularly on the girls faces + lightly increased saturation.

                    After seeing your correction I used Hue/Saturation at 100% saturation on it and saw what you meant about the very light tinge specially around head and feet of the girl on my left. (Attachment 3)

                    Probably, the selection you made wasn't very accurate that's why those spots had retained a subtle colour cast. Reselected the background, I used a Selective Color Adjustment Layer (Attachment 4) and the tinge disappeared.
                    Attached Files

                    Comment


                    • #11
                      Re: Completely white background, how to?

                      You can use any type of lighting for the front. One light is good but you could also use a main plus fill. You can certainly do this with 3 lights.
                      JerryCentral

                      Comment


                      • #12
                        Re: Completely white background, how to?

                        Originally posted by Flora View Post
                        Hi again,

                        using the Hue/Saturation at 100% saturation on your original you can see the different tinges in your background: yellow, red, magenta etc. and there are also a couple of patches of grey. (Attachment 1)

                        So, even before seeing your corrected version, I also opted for a selection and simply used a Levels Adjustment layer on the selected background.
                        (Attachment 2) from left: original, white background, adjusted luminosity particularly on the girls faces + lightly increased saturation.

                        After seeing your correction I used Hue/Saturation at 100% saturation on it and saw what you meant about the very light tinge specially around head and feet of the girl on my left. (Attachment 3)

                        Probably, the selection you made wasn't very accurate that's why those spots had retained a subtle colour cast. Reselected the background, I used a Selective Color Adjustment Layer (Attachment 4) and the tinge disappeared.
                        Thanks a bunch, Flora. Very informative! I just didn't want to spend additional time trying to correct color casts...etc. Because I work with time sensitive projects. Even dodging out the highlights take a lot of time and I want to be as efficient as possible!

                        Comment


                        • #13
                          Re: Completely white background, how to?

                          Originally posted by Algarve Images View Post
                          Yep,
                          looks like 3 lights and thats good for me too as i've ordered 3 elinchrom's from UK.
                          The D3 is clean up to 1600 and usable at 3,200/6400 for smaller prints, at 800 ISO there is no visible diference from base ISO of 200
                          Nice, I own a 5D and it does nicely @ higher ISOs, too bad it doesn't have an integrated portrait grip and current AF/ISO performance... >.<
                          WTB 1D Mark III!

                          Comment


                          • #14
                            Re: Completely white background, how to?

                            Originally posted by Algarve Images View Post
                            As Namphoto has already mentioned the ratio is important and an ideal high key setting would be 4 lights, for example if the subject reading is F8 then the two backlights burning the BG should be F11..
                            There is a diagram here at:

                            http://jerrycentral.com/2008/07/09/h...hting-diagram/

                            Another method, easier if you have a sunny window to place the subject in front of it make sure it has net curains or even better a white silk blind to diffuse the light.
                            Use fill flash, bump up the ISO and your bg should be burned out.
                            Here's an example taken in a living room against a bright window with only fill flash...
                            1/60 @ F4.5
                            ISO 1600
                            I underexposed the original so you can see the window, the covering is a net curtain and it worked...
                            Regards,
                            Gary...
                            I looked at your web site ... Nice work. I did notice a few of your High Key shots showed a little flare that degraded your contrast. Flare is quite a problem with high key so make sure that you have a clean lens and use a lens shade. If your background is too bright it will make flare. We try to light the background until it just starts to blink with over exposure on the LCD. The Black cards are also helpful in shading the lens and keeping the background lights from spilling on the subject.
                            Attached Files

                            Comment


                            • #15
                              Re: Completely white background, how to?

                              Not to put too fine a point on it, but the secret is not so much in the light intensity ratio between subject and a white background, but in the light intensity difference between those two. That difference needs to be 2 stops. I.o.w. the white background needs to reflect 2 more stops of light into the lens than the subject does. You achieve that by throwing much more light on that background than on the subject. (But too much, and you get flare. It's a precise balance).
                              This is where spot metering – but better yet: a separate flash meter – comes into its own. OTOH: simple test shots (with a stand-in 'subject', like a mannikin) help you find the ideal lighting setup ahead of the actual session.

                              When there's no going back to the set to reshoot you can try to rescue the shot in PP. The simplest way I sometimes use, if the photo lends itself to it (wispy hair is a killer): make a copy. Open it. Precisely select the subject. Invert the selection, so that the background is selected instead. Overexpose (In PS/CS3: Image–>Adjustments–>Exposure) by 2 stops. Voila!
                              Last edited by W.Smith; 03-25-2009, 11:59 AM.

                              Comment

                              Related Topics

                              Collapse

                              • ilegales
                                Quicker way to seperate White shirts on white bkg
                                by ilegales
                                i am retouching some kids who are wearing white shirts and shot on a white background

                                i want to make the whole background pure white 255.255.255 but still to keep the small shadows from their bodies /chairs

                                i am currently using the replace colour but wanted to know if theres...
                                10-12-2009, 08:22 AM
                              • Sam Bacon
                                Pure white highlights... how?
                                by Sam Bacon
                                Hi, all

                                I have been always wondering what would be the straightforward technique for making highlights be pure white which is quite common such as:

                                http://www.viennapaint.com/work/pop....x=380&posy=510...
                                04-02-2009, 03:29 AM
                              • Lorlee
                                Dirty White Seamless
                                by Lorlee
                                Well the seamless was not actually dirty but boy it caught lots of color casts! I took this picture outside and the sun was behind me so I had to use my black fleece to keep the sun from shining through the seamless. Now I do not have a clean seamless. I have tried many different ways to get a more...
                                04-23-2010, 12:35 AM
                              • mantra
                                how can make this building white ?
                                by mantra
                                Hi

                                i watched many photos about interior pools or building , they are perfeclty white

                                for example in this picture , i shoot in raw , white balance

                                but i can't get it white
                                in the reality it's white

                                how can make it white ?
                                ...
                                01-31-2013, 12:01 AM
                              • meadowlark
                                Using white when colorizing
                                by meadowlark
                                Hello again,

                                When colorizing using a black and white photo do any of you have any tips for getting the white to look natural, or is there a subtle tint you add to the white that works well when colorizing? I am finding that just straight white isn't looking right or doesn't have enough...
                                07-08-2010, 07:36 PM
                              Working...
                              X