Universal items to show size in photos?

I often add some sort of item to a photo to show the relative size of a thing. It's sort of a visual ruler.

For me, it used to be a Swiss army knife, but those come in different sizes too. And nobody carries them now. My various pocketknives are various sizes.

A standard Bic lighter or Bic stick pen is pretty universal. So is a business card.

In Canada, $1 and $2 coins (loonies and twonies) are understood, but that doesn't travel well across borders.

Ideally it's something that is usually close at hand. I have seen a golf ball used. Effective, but I probably won't have one when I need it.

What universally understood items would you suggest?

It obviously depends on the level of precision needed, but I often just use my hand. I have big hands. so that might confuse things, but most of the time my need is rough enough that a hand is a hand is a hand. And I never leave it back home or in the car!

There is an online group that I frequent that has the running joke of requiring a banana-for-scale in all photos. It is amusing but useful!

A usa or Canadian quarter make a good size indicator.  They both seem internationally recognized but it helps to have a traditional coin with the caribou, not one of the special issue ones.  I think they are a fraction of a mm different which is not important for most photos.

They are also very light weight and for a long time, useful for pay phones, so there would always be a couple in my pocket at all times.

I also use a coin. Hands and feet are too variable, in both length and width. The best thing I've found for real accuracy, is a ruler with both imperial & metric measurements. However, even though a 6inch one is small, it's just not something I'm likely to have in hand every time I need it.

I suppose it depends on what you're showing, but I do a lot of work in the area of forestry and environmental stuff and the classic is the Bic stick pen (or whatever standard simple single-use pen), it works well to show the size of tree trunks or stumps, ant nests, cutter heads, tires, tools, etc.

Golf or tennis balls are good references, if not easily available everywhere. And for smaller things, paperclips, keys and coins (despite size variations) are usually pretty good.

In geology, the classic is a rock hammer, with the point left touching the item of interest. Talk about things the average person doesn't carry! I've seen photos where even with an actual scale, the geologist throws in a rock hammer, too.

A coin (or several coins), a clip board, a water bottle, a hard hat, a pen, a pencil, a cell phone, a standard sized field book, business cards, credit card sized cards (like say, a library card), and a compass are all items i've seen used. Standard field books and compasses often have a scale on the cover for this purpose.

I've beeen known to use my index finger or my hand in a pinch, and have seen photos labelled with "and a [person in X profession] for scale".

Very creatively, sometimes people use an actual ruler too.

Great topic!
For something giant (trees, mountains) - a person.
A deck of cards.
I love photos with rulers when buying things like scions.
A banana is very universal.

Great replies!

A discarded CD/DVD is a universal size.

What about the ubiquitous 5 USG/20 litre plastic pail? Does that play well in Europe?

Perhaps eyeglasses/sunglasses could be a rough scale? They vary, but by  how much?

A digital wristwatch?

In Canada and the US, the red "Solo cup" and its knock-offs are pretty much a standard, recognized size.

And how about battery packs from name-brand battery powered tools?

The ones I generally see are tape measures, the yellow ones and quarters.

For large items, I try to use a 4’ level. It is chunky enough to show up well in a photo.  For smaller items, I grab whatever is handy…pen, coffee cup, etc … just as long as it has some universal relevance.

As I am usually photographing plants, imagine that, I will use my shoe, including my shoe size. or finger with ring size.

r ranson wrote:A usa or Canadian quarter make a good size indicator.  They both seem internationally recognized but it helps to have a traditional coin with the caribou, not one of the special issue ones.  

FYI - The British 10 pence piece is essentially the same diameter as the Canadian Quarter, it even has the Queen's (new ones, likely the King's) head on one side. The only obvious difference is that the 10 pence is thicker.

Someone pawned 4 of them off in our change bowl for eggs, in case you're wondering how I know... Anyone know anyone travelling to England?

Jay Angler wrote:
FYI - The British 10 pence piece is essentially the same diameter as the Canadian Quarter, it even has the Queen's (new ones, likely the King's) head on one side. The only obvious difference is that the 10 pence is thicker.

Excellent!

Side story -- there's a Filipino coin that's the same size as a Canadian loonie but only worth 13c. I got it as change -- made me annoyed until I realized it fit in the slot that unlocks grocery carts. Since it has no edges it's easy to pull out after unlocking. I drilled a hole, added a lanyard, and unlock a bunch of carts for other people while I'm there.

Jay Angler wrote:

r ranson wrote:A usa or Canadian quarter make a good size indicator.  They both seem internationally recognized but it helps to have a traditional coin with the caribou, not one of the special issue ones.  

FYI - The British 10 pence piece is essentially the same diameter as the Canadian Quarter, it even has the Queen's (new ones, likely the King's) head on one side. The only obvious difference is that the 10 pence is thicker.

Someone pawned 4 of them off in our change bowl for eggs, in case you're wondering how I know... Anyone know anyone travelling to England?

I was thinking of digging through my coin collection to see what coins I have that are the same size as the American Quarter (I think I might have a Canadian one, living as close to the boarder as we are), but I don't think I have any British pence pieces.

I went and dug through my coin stash and aligned them by size. A lot of the 10 cent coins are similar to many 1 cent coins...but there's also a bunch of other coin amounts down there.

The 25 and 20 cent pieces are largely similar, and there's a bunch of 1 dollar sized coins. But, some are worth 10 dollars/pesos or other denominations. It doesn't help that a lot of coins are now made with collectable fronts and backs. American quarters all used to have George Washington on the front, and an eagle on the back. But, now a lot of the backs are pictures of states, national parks, famous women, etc. Coins are hard!

I saw hands mentioned, but not toes.  The big toe is pretty universal in size, yes?;-)

I'd produce a photo of mine for example, but these days it's NSFW....likely to induce adverse reactions in the observer.  Ha!

Photo from  favorite Monty Python skit.....(source:  https://pythonluv.blogspot.com/2014/08/episode-21-archaeology-today.html  )

Nope. Toes are not universal. My sister has long skinny toes. I have shorter, middle-sized ones, my husband has middle length,  but very wide toes.  I have a friend with toes half the length of mine that are half again as wide - all this including the big toe. In fact, my ex's big toes were freaking ginormous...

My 10cents  worth,

Thumb, the bit with the nail is one inch, c.2.5cm, pretty much universal I believe.
When smoking, I used lighters, cigar boxes also useful for carrying harvested seeds.
Feet not so good as sizes vary a lot, eventhough one foot is 12 inches.

Sometimes, size is not shared: omg you should have seen it! like the fish that got away - I don’t fish

As mentioned, it’s what is immediately available to give others an idea of dimensions.

Blessings
M-H

marie-helene kutek wrote:My 10cents  worth,

Thumb, the bit with the nail is one inch, c.2.5cm, pretty much universal I believe.

I wonder....

I just realized: AA and AAA batteries are universal in size. I usually have a 1-AAA flashlight in my pocket.

Edit: To qualify, they are universal in length. Their girth can vary quite a bit.

Douglas Alpenstock wrote:I just realized: AA and AAA batteries are universal in size. I usually have a 1-AAA flashlight in my pocket.

I believe 9v are, as well.