How do I change background color to white?

If you only need to lighten the background a little you can use the Dodge tool. It's found in the Adjustments panel; then Adjustments drop down menu > Quick Brushes > Dodge (Lighten). For your product I expect ticking the Detect edges box will make it quite easy. After brushing the background you can you the slider to increase or decrease the effect.

Hope this helps.

Lucrosus,

Welcome to the user-supported Aperture discussion forum.

If you truly had a white paperboard, then it sounds more like a photography issue than a digital management issue.

When you use automatic exposure on your camera, it generally tries to make the image have "18% gray" overall. So, if you take a photo of a pure white paperboard, your camera will make the exposure such that it is "18% gray" and not actually white. Your camera, rather than you, chose the exposure, making it underexposed according to you. You didn't want 18% gray -- you wanted white.

If your paintbrush is a small part of the picture (and it probably is no more than 1/4 of the pixels of the photo), the light from the paperboard was factored into the automatic exposure much, much more than the light from the brush. So, you may want to try moving the exposure slider to the right.

On the other hand, if there is any cast of a color in your gray, it may be a white-balance issue. Try using the "dropper" in the white-balance adjustment to choose the background color and see what Aperture makes of that. I have a feeling this won't accomplish what you want, though, as gray is simply a shade of white.

nathan

As well as the dodge tool how about increasing the overall exposure a stop or two and then using the burn tool to bring the paintbrush back up? The shadow is not too distracting - in fact it may even add a feeling of depth. Perhaps bring the blue slider down a little, and experiment with other adjustments.

Hi Lucrosus.

As nathan points out, this is really a photography question, not an Aperture question: the problem is with your original, and the solution lies there. The best advice I can give you is to talk to a photographer who specializes in product shots.

That said, there are at least a few things you can do in Aperture to get closer to the effect you want.

First, the paper is showing as blue, not gray. It also varies in blueness from bottom to top (the top is lower in luminance and bluer).

A White Balance adjustment can help. In the example below, I set to white balance to an area between the two brush handles.

In general, one can force the over-exposure (over exposure = white) by changing the white point using some combination of the Exposure slider and the Curves and Levels Bricks. In your capture, the reflection off the ferrule is the brightest part of the picture. Adjusting the white point so the paper is appears white completely over-exposes the ferrule. The solution using Aperture is to apply the adjustments as needed for the paper, and then +brush away+ the adjustment from the area where it is undesirable.

Here is a quick-and-dirty attempt to get you closer to what you want:



The darker areas of the paper are still blue. And the shadow under the brush hasn't been touched.

If you want to completely cut-out your brushes from the background, and show them on an opaque background of any color -- that's a job for Photoshop or another image editing program. My sense of this remains, however, that your time would be better spent improving the source photographs rather than attempting to fix them in PP.

Was the original import JPG or RAW? If its JPG you'll be extremely limited in the adjustments you can make especially to white balance. Looking at the image you posted I'd say it' mostly a white balance issue.

Can you retake the shot? If so take it in RAW you'll have much more latitude once you're back in Aperture. If you can't take RAW what type of camera are you using and what are your choices for white balance? What was the lighting setup?

If you're camera has a custom white balance setting that would be the way to go. If not take a series of shots with each of the white balance setting you do have. Remember this only applies if you are shooting JPG, if you can shoot in RAW none of this matters.

Played around a bit. Unfortunately when you try to drive the background to white the overall picture gets somewhat harsh and the noise increases. If you can't retake the shot you might have better luck in an image editing application, PS, The GIMP, etc. You probably could do something with layers.

When creating Apple books (well in fact it was a Bob book but I did it in Aperture and exported it) I found a nice tip using Curves. I'm not in front of Aperture now so forgive me if this is slightly vague. I used curves to effectively reduce the opacity of an image and turning it slightly whiter (if that makes sense). Anyway using this technique you can turn an image completely white if you take the effect to the extreme and then just brush in the effect (with detect edges ticked).

So go in to curves and expand it. Grab the 'curve' at the bottom left of the graph (where the x and y axis meet) and drag it vertically upwards. If you go to an extreme you will be left with a horizontal curve and the photo will turn white. This gives the reduced opacity effect I described above.

Additionally you can grab the slider on the bottom right of the curve (along the x axis)and drag it to the left. The highlights will start to get blown out. Once the grey area is white stop, it will look a bit odd. But you then want to brush this effect in just to the grey areas. The rest of the photo ie the brushes will now remain unaffected.

If its still showing slightly blue just go to the B&W brick and brush that in to the white / blue area. This will give you a completely white background and the brushes will be unaffected. (Note you may want to zoom in to ensure your brushing in is accurate). I can try and have a go tonight if I remember.

Ok, I have carried out the adjustments I described and all looks good with a white background and the paintbrushes unaffected. But not sure how to link the image to this forum. I can send it somewhere if someone wishes to see the result.

Regards

Sent.....