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We are opening an Amazon store selling women's pajamas and would like to take good photos of our merchandise.

We have 2 lens options: Nikon 50mm f1.8 or a zoom lens 18-105mm.

What would you recommend for lens selection and settings such as shooting mode, aperture, shutter speed so the images show perfectly all areas of the garment?

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    \$\begingroup\$ Product photography is all about lighting and very little about your camera. What do you have in the way of a lighting set up? \$\endgroup\$
    – Philip Kendall
    Commented Feb 17, 2015 at 14:10
  • \$\begingroup\$ I am conscious about lighting but my main concern is to pick the right lens and not having any blurring \$\endgroup\$
    – samyb8
    Commented Feb 17, 2015 at 15:44
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    \$\begingroup\$ The way you have no blurring is to stick your camera on a tripod. Nothing to do with your lens. \$\endgroup\$
    – Philip Kendall
    Commented Feb 17, 2015 at 16:06
  • \$\begingroup\$ Sorry for the misunderstanding, I meant depth of field. My fixed 50mm gives great DOF but that does not work for clothes \$\endgroup\$
    – samyb8
    Commented Feb 17, 2015 at 16:20
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    \$\begingroup\$ With a controlled still-life, don't set your lens wide open. Find out its sharpest setting, e.g. f/5.6, and use that. At the distance you need for a 50mm lense in APS-C, the depth of field you need (18 inches?) is well within range. use a tripod, no excuses. \$\endgroup\$
    – JDługosz
    Commented Feb 20, 2015 at 10:28

3 Answers 3

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Lens selection is largely irrelevant for this task since the end result will be fairly low-resolution, any mid length fixed (prime) or zoom lens should be fine so long as it gets everything in. Certainly both the proposed lenses will be good enough.

In this situation just about every other factor apart from the body & lens is actually what's important to getting a good image that will give you sales.

Getting a decent image depends entirely on the lighting. The settings you need to use in-camera also depend entirely on the light available. Without adjusting the light the main camera control you'll need is the Aperture, which controls your depth of field. Using a setting of f/8 or f/11 as recommended by Henk in Aperture Priority (A/Av) mode should get you the sharpness you need.

The tradeoff to 'stopping down' will be that to get the same amount of light requires longer shutter times or more power from the flash depending on how you're lighting the set. If you find you have blurry images then it is probably down to camera shake which you can fix with a sturdy tripod and either a remote release or the self timer.

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If your relying on your images to sell your product they need to be good. Better than your competitors. From your comments about lens choice i would say you have absolutely no idea what your doing. Harsh and i mean that in a nice way. Think about what you need to start with.- Accurate full spectrum lighting. If your colours are off you will be getting returns. Nothing worse than buying a shirt you thought was cream and its actually white or brown that is really black or has a pocket that was too poorly lit to see etc etc. Knowledge of how to expose black fabric , white fabric and maybe even fluoro all together and make it look consistent. Again returns and not looking professional. Remember how you look in front of your customers is everything. If you spend a little on having your photography done professionally you will sell more and more than cover the cost. You need to think carefully about that. For me personally when shooting this sort of thing. My setup is NEVER a set and forget. Im constantly changing this and moving that. Almost every shot. The only thing that stays the same is the result.

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Whenever possible, I use focus stacking to get around the finite depth of field. The highest F-number you can choose before the diffraction limit will cause unsharpness depends on the size of the pixels in your sensor, typically you'll start to be affected by it above F/6.

If you don't want to do focus stacking, then the optimal settings can be computed as follows. First, look up the pixel size r for your camera sensor. E.g. for my camera r= 4.2 micrometers. Let's denote the focal length by f, e.g. f = 50 mm. The aperture is the D = f/F where F is the F-number, e.g. F = 6.

If an object at distance d is focussed at distance x behind the lens, then the good old lens equations tells us that x and d are related according to:

1/x + 1/d = 1/f

A little algebra is needed to show that if an object at distance d1 is in focus then an object at distance d2 will create a spot on the image sensor of size

f^2/F |(1/d1 - 1/d2)|

Here one assumes that the dostances are much larger than the focal length. Then if the size of this spot is smaller than the pixel size, you will still have perfect focus for that object at distance d2. It is convenient to define the so-called hyperfocal distance H as:

H = f^2/(F r)

(this gives the minimm distance you need to focus on before all objects farther away than this distance are in focus)

Now suppose that we take a picture of a nearby object a distance d away such that d is much smaller than H (say d = few meters, and typically H is many dozens or even hundreds of meters). For such cases the formula for the depth of field (dof) reduces to:

dof = d^2/H

We can rewrite the formulas as follows:

H = 104 meters *(f/50mm)^2 *(6/F) *(4 micrometers/r) ---->

dof = 9.6 millimeters *(d/meter)^2 * (50 mm/f)^2 * (F/6) * (r/4 micrometers)

Unsharpness due to diffraction will start to occur at F numbers above:

F_diffraction = r/(2.44 lambda)

where lambda is the wavelength of light. When the green part of the spectrum starts to be affected by diffraction, then we really start to notice this. So, we can put lambda = 500 nanometers and write the formula as:

F_diffraction = 3.3 * (r/4 micrometers)

This is when the width of the interference pattern starts to become larger than one pixel, it will really become a problem when the width is two pixels wide, which happens at F = 6.6* (r/4 micrometers).

So, F = 6 is roughly the upper limit when considering how to optimize the variables that yileds an image capturing as much detail as possible. The optimal choice is obviously to put the object as closeby as possible and/or to use as large focal length as possible such that the entire object is still perfectly in focus. In that case, as much of the field of view is covered by the object, you thus have the maximum possible number of pixels covering the object.

Suppose that a piece of clothing has a length of L and you photograph it perpendicularly from a distance d away. Then points on the clothing will be between d and sqrt(d^2 + L^2/4) away, assuming that the thickness can be ignored relative to this range in distance in the perpendicular direction. The minimum dof you then need is thus given by:

[sqrt(d^2 + L^2/4) - d]/2

If the dof is just equal to this, then you are at the optimum:

[sqrt(d^2 + L^2/4) - d]/2 = 9.6 millimeters *(d/meter)^2 * (50 mm/f)^2 * (F/6) * (r/4 micrometers)

The exact solution of this equation looks rather unwieldy, but you can solve it approximately by using the fact that d will in practice need to be significantly larger than L/2. You can then expand the square root in powers of (L/d)^2, this reduces the equation to leading order to:

1/16 L^2/d = 9.6 millimeters *(d/meter)^2 * (50 mm/f)^2 * (F/6) * (r/4 micrometers) --->

1/16 L^2/meter^2 = 9.6 *10^(-3) *(d/meter)^3 * (50 mm/f)^2 * (F/6) * (r/4 micrometers)

d = 1.87 meter (L/meter)^(2/3)(f/50 mm)^(2/3) * (6/F)^(1/3) * (4 micrometers/r)^(1/3)

So, if it is 1 meter long, you need to be roughly 2 meters away to make sure everything is in focus. The smallest details visible on the clothing is given by d r/f (note that r/f is the angular resilution due to the finite pixel size and this nagle corresponds to a distance of of d times that angle = d r/f between points on the object). In the optimal case this is:

0.15 millimeters (L/meter)^(2/3)(50 mm/f)^(1/3) * (6/F)^(1/3) * (r/4 micrometers)^(2/3)

This means that for clothing of the order of 1 meter long, you are going to be limited by a resolution of a few tenths of a millimeter. The only way to beat this limit is to take pictures form closer by than allowed by the constraint of getting everthing sharp in one go, hence the need to do focus stacking.

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