Which lens for a vacation?

One of the frequently asked questions I hear is, "What lens(es) should I bring with me on my vacation?"  In this post, I would like to suggest how you can narrow down your choices.  I am also going to discuss the cameras and lenses that I will bring for my upcoming vacation to Italy.

CHOOSING YOUR EQUIPMENT FOR A VACATION

I think that in order to choose the right combination of equipment, we should consider our requirements, then examine the characteristics of the equipment and compare them with how well they match our requirements.

I believe our requirements depend not just on our personal preferences, but also on the nature of the vacation. 
- What kinds of photos do you want to take? For example, scenery, environmental portraits, selfies, portraits, group shots, animals, small objects, underwater, night time photos, etc.?  These will dictate the focal lengths (and possibly camera(s)) that you need.  You may want to look at travel photos of the location you're visiting to get ideas of the kinds of shots you want to take.
- Is it more of a vacation, or a photographic trip?  If it's more of a vacation, we become less sensitive to image quality. 
- Is it for a short trip or a long one?  The longer it is, the more likely you'll need something versatile. 
- Is it a casual trip or a once-in-a-lifetime trip?  If it's once-in-a-lifetime, we are more likely to prioritize focal length coverage and image quality than convenience and cost.
- Are you going by yourself or with your family?  That could affect what kinds of focal lengths you need, and how important convenience is to you. 
- Are you on your own time or are you on a tour with a schedule?  That could affect how important convenience is.

To choose the equipment that will fulfill those requirements, we need to consider their characteristics:
- image quality, which is dependent on the sensor(s) and lens(es);
- low light capability, if you will be taking photos in low light conditions. This is a function of the high ISO noise capability of the sensor(s), the maximum aperture of the lens(es), the low light autofocus capability of the camera, and image stabilization (if any);
- convenience, which is dependent on the size and weight of the cameras and lenses, the range of focal lengths available at any given time (zooms vs. primes), and the number of cameras and lenses you are bringing;
- video capability, if that is important to you;
- cost, if you're purchasing equipment specifically for the vacation.

(For simplicity, if low light is one of your requirements, you can collapse image quality and low light capability because they largely overlap.)

Of course it would be great if you could have it all: a small, lightweight camera that covers a wide range of focal lengths, with exceptional image quality even in low light.  Realistically, you'll have to weigh these characteristics and prioritize, based on your requirements.

EXAMPLE: CASUAL TRIP
On a casual trip, image quality would not be as important to me.  In my case, I would bring the Sony a6000 with Sony 18-105 f4, or the Olympus Stylus 1.  Both are convenient and cover a wide range of situations, from scenery to portraits to wildlife.

If shooting at longer focal lengths is not important, I would also consider a Sony a6000 with its compact 16-50 PZ kit lens, or a Samsung NX500 with 16-50 kit lens.

EXAMPLE: TRIP TO ITALY
As for my upcoming trip to Italy, it's a vacation, not a photographic assignment.  On the other hand, it's not likely that we'll get the chance to go back there again in the foreseeable future. Because of this, I would give a higher priority to image quality and focal length coverage.  I'm willing to sacrifice some convenience.

In order of priority, I plan to take these kinds of shots, and here are the 35mm equivalent focal lengths usually associated with them (of course there are exceptions):
- environmental portraits. 24-36mm.
- architecture.  ultrawide.
- scenery. 24mm or wider. Alternatively, telephoto for compression.
- selfies (hey, I'm honest).  24-36mm.
- street. 24-50mm.

If I had an unlimited budget, I would want a 24-70 2.8 on full frame, or the Sigma 18-35 1.8 and an APS-C body. For ultrawide, I would like a fast ultrawide such as the Nikon 14-24 2.8 on full frame, or Tokina 11-16 2.8 on an APS-C body. I'd also want a Sony RX10, Panasonic FZ1000, or Olympus Stylus 1 to cover longer focal lengths, just in case.

In the real world, I don't have those lenses (other than the Stylus 1).  Here are the bodies and lenses I am bringing to cover those ranges.  I brought them to Disney's California Adventure to test how well the combination would work:

1. Sony a6000 + Sony 16 2.8 with ultrawide converter (24mm equivalent; 18mm with converter) for scenery and architecture.  

It can also be used for environmental portraits and street photography.

2. Samsung NX500 + kit lens for general photos and 20 2.8 (31mm equivalent) for environmental portraits, selfies, candids, and street photos.

3. I would also bring the Stylus 1, just in case I need a longer focal length.

short telephoto shot from mezzanine level

300mm equivalent

I'm bringing a small tripod for low light and slow shutter shots. The one I'm bringing is the Joby Gorillapod Hybrid.  I also got extra quick release plates for each camera.

I don't expect to use flash, but I have a small flash for each (the Sony HVL-F20M and the Samsung clip-on flash). They won't take up much space.

Even with all those, I would still have space for one more lens.  I was torn between the Sony 18-105 f/4 OSS for versatility and the Sony 35 1.8 OSS for low light.  I ultimately chose the 18-105 because I think for low light shots, I would be indoors and would want a wider focal length, therefore the 35 1.8 won't be as useful (24 1.8 would be much better but I don't have that lens).  That means I'll have to rely on the Sony 16 2.8 or 20 2.8 for low light.  An aperture of f/2.8 is not that great but it's acceptable I guess.

Finally, I still have space for a Fuji W3 3D camera, which I'm also bringing along.  I know most people think 3D photos are gimmicky, but I enjoy shooting with the W3 and the unique challenge of composing for 3D.

I just uploaded a video of the equipment I'm bringing.  Note: I've changed my bag into a small sling-type camera bag, which I think has the right size for mirrorless cameras (the bag measures 13" x 7.5" x 16" or 31.4 x 17.5 x 39.1cm).

P.S. Since I will be on vacation, I probably won't be posting anything until around the second week of June.

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