Semantics of "100% crop"

[Aberaeron]

I can't agree. I am a scientist by profession. So is my wife. Any person who is not familiar with the terminology will automatically assume that 100%crop is confusing as it sounds like "the whole image". A 50% crop would be half chunk of the original image to anyone not familiar.

That is just the way it is. You have to understand that being familiar with a term does not make it a good choice of words. Truly it is counterintuitive.

In fact the process of 100%crop is not that simple to explain.

All of us have needed to learn the meaning and usage of terms such as 100% crop when we came into digital photography. We all managed to do that, but with a whole lot less kicking and screaming.

Dave

 

[John Michael Winterbourne]

Sorry, that's just silly. If I asked about what "100% crop" means in my professional work-place (Forestry, Agri-environment), no-one would think I was talking about one of the easier digital photography concepts to take on board. A crop is something that's planted, looked after, and harvested? Surely? And just in case you think I'm being unnecessarily confrontational, you might like to know that "whole crop harvesting" (=a 100% crop?) was briefly a contentious issue in UK forestry in the 1980s.

But this is semantics which = where words come from and what they can mean now. I think that the idea of "cutting" is probably fairly important, from way back. Probably why a regular poster on here has taken recently to suggesting people take a pair of scissors to a photograph/piece of paper to see what difference it makes to the appearance of the cut-out portion. Answer? None.

If I want to harvest my wheat crop, I cut it. But in a different professional environment - let's say hairdressing - what would a "100% crop" mean there?

I think it really is time you gave up on this.

 

[cookedraw]

Ok, my display have 300+ pixels per inch so what you call "100%crop" makes little sense for any other use than editing, it looks very good viewed at pixel per pixel ratio.

 

[xroxer]

(sigh-facepalm) I would obviously make it clear I'm talking about photographs. "Here is the original photo, please make a 50%crop and give it back to me". As I said, very counterintuitive.

 

[Aberaeron]

(sigh-facepalm) I would obviously make it clear I'm talking about photographs. "Here is the original photo, please make a 50%crop and give it back to me". As I said, very counterintuitive.

It looks to me as if you both agree. 50% of a crop is half of the full crop. Why some idiot decided otherwise in photographic terms must be one of life's many mysteries. That's if indeed the definition or its interpretation really is different within photography.

On my iMac, using photos, I consider a 100% crop to be a 100% magnification [double size] cut to fit the original frame. It must be right, because it says so on the slider at the top of the Photo app screen.

So even within photography it means different things to different people. Even to those that consider these things to be worthy of spending brain energy on.

 

[cookedraw]

(sigh-facepalm) I would obviously make it clear I'm talking about photographs. "Here is the original photo, please make a 50%crop and give it back to me". As I said, very counterintuitive.

It looks to me as if you both agree. 50% of a crop is half of the full crop. Why some idiot decided otherwise in photographic terms must be one of life's many mysteries. That's if indeed the definition or its interpretation really is different within photography.

On my iMac, using photos, I consider a 100% crop to be a 100% magnification [double size] cut to fit the original frame. It must be right, because it says so on the slider at the top of the Photo app screen.

So even within photography it means different things to different people. Even to those that consider these things to be worthy of spending brain energy on.

seriously, stop, just stop and think people... we all understand how the terminology is used, but this is not what the thread is about really.

100% magnification is 1x magnification, 200% magnification is 2x , 400% is 4x..

This is how it is.

So a crop with half of the frame remaining should be either :

1. 200% crop ( where the 200% indicate the magnification ratio if viewed at full screen )

2. 50% crop ( a crop with 50% of the original image left after discard of 50%)

--
" Use the shutter button on the headset cord " - Leonardo Da Vinci

 

[chuxter]

Just semantics and not very important but I was wondering the following:

The term 100%crop initially confused the heck out of me. I read some old dpreview threads on it and found that while I understood the definition it still seemed a very poor choice of terminology.

Interesting that you would pick that one of the hundreds of senseless terms that the "photographic guild" use w/o thinking. Note that I formerly was a member in good standing of the "photographic guild"; I learned the language from my father, who was also a guild member.

All "guilds" are like this. Ever try to communicate w/ a plumber or electrician? How about your friendly auto mechanic? We had a lively discussion last week about the terminology involving bikes [not w/ a motor]. These "bike guild" members have a VERY strange language and are proud of it! Try Googling "crank", "cog", and "cassette". And they call the number of "speeds" available, the number of "gears" in spite of not having a SINGLE gear. ;-) Add a motor to a bike and the language is totally different!

This is actually a good metaphor...

You have the front cog and the rear cog , a group of rear cogs is called cassette, if the cassette have 6 cogs it is a 6 speed cassette, if the cassette have 10 cogs it is a 10 speed cassette.

If the chain is on a 40 teeth front cog and a 20 teeth rear cog, the gear ratio is 2 to 1, or 2:1 , or 200%.

One 360° crank on the front cog equals 720° on the rear cog.

Now move the chain to a 10 teeth cog on the rear cassette while keeping the chain on the 40 teeth front cog and you have a gear ratio of 4:1.

Just like "shutter speed" is nonsense [it is correctly called "exposure time"], a "gear ratio" is correctly called a "drive ratio", especially when no actual GEARS are involved...like if sprockets/chains or v-belts are the mechanisms that deliver the motion.

My Prius has a CVT. It uses a metal V-belt between two pulleys that change their spacing [under control of the computer]. It is incorrect to refer to a Prius having a "gear ratio", because it doesn't. It also doesn't have a "sprocket ratio" or a "cog ratio" or a "belt ratio". It, like all machines of this type, has a "drive ratio" which is independent of the details of the design.

It is perfectly correct and 100% logic. The bicycle is also 100 year old in more or less unchanged form so it is not a surprise that science caught up to marketing terminology.

The bicycle goes back a long way. Some people say it was invented by Caprotti in 1493. But it was intended to be made of wood. In 1886, Swift made a "Safety Bicycle":



https://en.wikipedia.org/wiki/History_of_the_bicycle

It looked very similar to what we ride today [it didn't have any gears either].

So, I'd say the bicycle is at least 130 years old.

In contrast, the motorcycle was invented in 1894; Hildebrand & Wolfmuller became the first series production motorcycle, and the first to be called a motorcycle. So, the motorcycle is at least 116 years old. In contrast to the bicycle, a motorcycle HAS gears, thus "gear ratio" is OK.

I prefer motorcycles because they don't have "cassettes"...I had a car once that had a cassette player.

 

[Gerry Winterbourne]

Problem is that it is counterintuitive to a newbie. Let me ask around work (full of PhD really smart people) and ask "what do you think 100%crop means"?

OK. So these people are trained to use sense and logic rather than just rely on instinct and intuition.

I suspect that every single person will be initially confused as it sounds like "the whole image".

I doubt if they'd be confused. But they probably would be puzzled, which is different. Their puzzlement would come from not knowing the terminology of a new (to them) subject.

Being logical they would try to work out what the term means by braking it down into the two parts "100%2 and "crop". The first thought about 100% is that it means "all", "all of" or something like that but it is also used to denote a fraction - specifically 1/1 in contexts where other fractions might also be considered. Hmmm ... that's not helped so far.

So "crop" - clearly this is related to cutting. What do photographers cut? Pictures. So crop probably means a part cut from a picture. Right. So now we go back to 100%. Well, if it means all (of) and we're thinking of cutting out a part, 100% means uncropped (because that's what all of the picture is).

Being not only sensible and logical these smart people probably see photographers as perhaps not quite so smart but certainly not idiots. So they say to themselves "if 100% means all of the picture = uncropped, then 100% crop would mean uncropped crop, which is nonsense and as photographers aren't idiots it can't mean that".

At that point they would realise that just from the plain expression it isn't possible to work out what it does mean but it is easy to work out that it certainly can't mean "the whole image".

I then will ask them "what do you think a 50%crop means"? At that point logic will tell them it means 50% of the image has been cropped away.

And they will say "but as we can't work out what 100% crop means you'll have to tell us" and then the meaning of 50% crop is immediately obvious.

See the problem!!!

There isn't one.

What there is is the plain fact that in virtually no sphere in which technical terms are instantly understandable without some basic knowledge of that sphere and some explanation of the term.

"Quantum" just means "amount" in Latin. Without a lot of background knowledge how could anyone infer what quantum physic means just from looking at the words? Does that make the term stupid?

As I said in an earlier post, "lens" just means "lentil" in Latin. Without a lot of background knowledge how could anyone infer what photographic means just from looking at the words? Does that make the term stupid?

I could use up the 6000 word allowance here with similar examples.

 

[chuxter]

I then will ask them "what do you think a 50%crop means"? At that point logic will tell them it means 50% of the image has been cropped away.

And they will say "but as we can't work out what 100% crop means you'll have to tell us" and then the meaning of 50% crop is immediately obvious.

This where I, for one, get confused. Although you didn't say so, I assume you are implying that you don't think that xroxer's understanding is correct [if so, why would you and others be arguing w/ him?]. I know that you are quite intelligent and knowledgeable. But I can't make sense of your above sentence. It is not immediately obvious that a 50% crop is NOT what xroxer says; it's half of an image [not sure WHAT half, but the simple definition is that it is cropping to half of the original image size]. It's not even obvious after I think about it really hard. I can't imagine it being anything else...

Which brings us back to what does the term "100% crop" mean? And that meaning must give clarity to "50% crop" and "200% crop".

 

[xroxer]

LOL, the problem is not that we haven't learned the meaning. The problem is that the terminology is counterintuitive. The reason that people will get "confused" is because they know what "crop" means already, and they know what "%" means already and logic tells them that %crop means a 'percentage of the original image is cropped'.

This is how it is. I guarantee everyone I ask will have the same issue. My wife did. My father who is also getting into photography did. "That is just STUPID" is what I hear when I tell them what it actually means.

The term was poorly chosen. You can hold onto the belief otherwise as tight as you wish.

 

[Gerry Winterbourne]

I then will ask them "what do you think a 50%crop means"? At that point logic will tell them it means 50% of the image has been cropped away.

And they will say "but as we can't work out what 100% crop means you'll have to tell us" and then the meaning of 50% crop is immediately obvious.

This where I, for one, get confused. Although you didn't say so, I assume you are implying that you don't think that xroxer's understanding is correct [if so, why would you and others be arguing w/ him?].

No. xroxer's point throughout this thread is that although he understands what we mean by 100% crop he considers it a foolish expression. We (or, at least, I and several others) are not debating his understanding of the term but his condemnation of it.

I know that you are quite intelligent and knowledgeable. But I can't make sense of your above sentence.

You have to take it in the context of what I had written above. In brief, xroxer said that a clever person would just think that 100% crop means the whole image; I said that a clever person could not without being told work out any meaning for it; but once being told what 100% crop means it's obvious what other %age crops mean.

It is not immediately obvious that a 50% crop is NOT what xroxer says; it's half of an image [not sure WHAT half, but the simple definition is that it is cropping to half of the original image size]. It's not even obvious after I think about it really hard. I can't imagine it being anything else...

Until this thread I'd never seen the expression 50% crop. That's because, I imagine, that the idea has no practical utility.

Which brings us back to what does the term "100% crop" mean?

It means (as xroxer has acknowledged throughout) a crop - part rather than all of - from an image viewed at 100% in pixel terms - that is, each image pixel gets one sensor pixel. Another way of saying it is full resolution but that takes longer to type.

This, of course, has great practical utility. People are always posting 100% crops here to illustrate some point about full-resolution images without posting the whole image at full resolution.

And that meaning must give clarity to "50% crop" and "200% crop".

Which is what I said but you failed to understand.

 

[Gerry Winterbourne]

LOL, the problem is not that we haven't learned the meaning. The problem is that the terminology is counterintuitive. The reason that people will get "confused" is because they know what "crop" means already, and they know what "%" means already and logic tells them that %crop means a 'percentage of the original image is cropped'.

Logic and intuition are different.

This is how it is. I guarantee everyone I ask will have the same issue.

How do you ask? (This is like framing opinion polls). If you present someone with a true 100% crop and say "this is a 100% crop - do you understand what that means?" my experience is that every photographer understands immediately. Or, to put it another way, in hundreds of posts here where people have presented 100% crops I have never seen a response "what do you mean".

My wife did. My father who is also getting into photography did. "That is just STUPID" is what I hear when I tell them what it actually means.

The term was poorly chosen. You can hold onto the belief otherwise as tight as you wish.

Ok. Give me an alternative that is clear, unambiguous and precise but also brief enough for frequent use.

 

[LynniePad]

I doubt if they'd be confused. But they probably would be puzzled, which is different. Their puzzlement would come from not knowing the terminology of a new (to them) subject.

Being logical they would try to work out what the term means by braking it down into the two parts "100% and "crop". The first thought about 100% is that it means "all", "all of" or something like that but it is also used to denote a fraction - specifically 1/1 in contexts where other fractions might also be considered. Hmmm ... that's not helped so far.

So "crop" - clearly this is related to cutting. What do photographers cut? Pictures. So crop probably means a part cut from a picture. Right. So now we go back to 100%. Well, if it means all (of) and we're thinking of cutting out a part, 100% means uncropped (because that's what all of the picture is).

Being not only sensible and logical these smart people probably see photographers as perhaps not quite so smart but certainly not idiots. So they say to themselves "if 100% means all of the picture = uncropped, then 100% crop would mean uncropped crop, which is nonsense and as photographers aren't idiots it can't mean that".

At that point they would realise that just from the plain expression it isn't possible to work out what it does mean but it is easy to work out that it certainly can't mean "the whole image".

That's was my analysis some posts ago, but then I'm intelligent as well as logical (and flexible).

Intuition can get you into strife. The controls on my Sony a7 were "too intuitive" and fooled me into thinking that they were doing something completely different to what I had thought.

Rather embarrassing; I should have RTFM.

 

[cookedraw]

I then will ask them "what do you think a 50%crop means"? At that point logic will tell them it means 50% of the image has been cropped away.

And they will say "but as we can't work out what 100% crop means you'll have to tell us" and then the meaning of 50% crop is immediately obvious.

This where I, for one, get confused. Although you didn't say so, I assume you are implying that you don't think that xroxer's understanding is correct [if so, why would you and others be arguing w/ him?].

No. xroxer's point throughout this thread is that although he understands what we mean by 100% crop he considers it a foolish expression. We (or, at least, I and several others) are not debating his understanding of the term but his condemnation of it.

I know that you are quite intelligent and knowledgeable. But I can't make sense of your above sentence.

You have to take it in the context of what I had written above. In brief, xroxer said that a clever person would just think that 100% crop means the whole image; I said that a clever person could not without being told work out any meaning for it; but once being told what 100% crop means it's obvious what other %age crops mean.

Ok, so what is other %age crops ?

It is not immediately obvious that a 50% crop is NOT what xroxer says; it's half of an image [not sure WHAT half, but the simple definition is that it is cropping to half of the original image size]. It's not even obvious after I think about it really hard. I can't imagine it being anything else...

Until this thread I'd never seen the expression 50% crop. That's because, I imagine, that the idea has no practical utility.

Which brings us back to what does the term "100% crop" mean?

It means (as xroxer has acknowledged throughout) a crop - part rather than all of - from an image viewed at 100% in pixel terms - that is, each image pixel gets one sensor pixel. Another way of saying it is full resolution but that takes longer to type.

This, of course, has great practical utility. People are always posting 100% crops here to illustrate some point about full-resolution images without posting the whole image at full resolution.

And that meaning must give clarity to "50% crop" and "200% crop".

Which is what I said but you failed to understand.

 

[xroxer]

How about:

"What is a 100%crop of a photograph?"

I predict the answer will be "It means the entire photograph - no cropping". The point I tell them that is wrong the confusion sets in. The point I explain to them the true meaning is the point I usually get "well that is stupid".

Intuitively or logically or whatever it makes more sense to use %crop to mean the amount cropped. Not perfect but much better IMO.

Let's compare both definitions using one example:

Example - I take a photo and send it full size to a friend and he emails back asking for me to send him a 50%crop.

My definition - I crop out 50% of the photo from the original attempting to keep subject matter in and send it.

Your definition - I first resize the original photo (50% scale reduction) and then arbitrarily select a crop size, and then crop attempting to keep subject matter in and send it

 

[LynniePad]

Let's compare both definitions using one example:

Example - I take a photo and send it full size to a friend and he emails back asking for me to send him a 50%crop.

My definition - I crop out 50% of the photo from the original attempting to keep subject matter in and send it.

Your definition - I first resize the original photo (50% scale reduction) and then arbitrarily select a crop size, and then crop attempting to keep subject matter in and send it.

I can't recall seeing reference to such a circumstance as a 50% crop.

There's an immediate problem with a so-called 50% crop...

• Your definition - 50% of the photo is presumably by area, or scaling both axes by a factor of 0.707.
• The conventional definition - 50% scale reduction is a factor of 0.5, leading to 25% of the original area.

Why would it be any more difficult to crop the down-scaled image so as to retain the subject?

 

[xroxer]

When you first scale you lose information and detail. If you crop from the original the crop retains all the detail from the original.

According to my definition a 50% crop will have 50% of the pixels from the original but that area of pixels will have full information form the original.

Loading…

richditch.wordpress.com

 

[LynniePad]

When you first scale you lose information and detail. If you crop from the original the crop retains all the detail from the original.

According to my definition a 50% crop will have 50% of the pixels from the original but that area of pixels will have full information from [that part of] the original.

You seem to be slowly getting your head around this, but it really is such trivial stuff that I can't be bothered with it any longer.

 

[chuxter]

I then will ask them "what do you think a 50%crop means"? At that point logic will tell them it means 50% of the image has been cropped away.

And they will say "but as we can't work out what 100% crop means you'll have to tell us" and then the meaning of 50% crop is immediately obvious.

This where I, for one, get confused. Although you didn't say so, I assume you are implying that you don't think that xroxer's understanding is correct [if so, why would you and others be arguing w/ him?].

No. xroxer's point throughout this thread is that although he understands what we mean by 100% crop he considers it a foolish expression. We (or, at least, I and several others) are not debating his understanding of the term but his condemnation of it.

I know that you are quite intelligent and knowledgeable. But I can't make sense of your above sentence.

You have to take it in the context of what I had written above. In brief, xroxer said that a clever person would just think that 100% crop means the whole image; I said that a clever person could not without being told work out any meaning for it; but once being told what 100% crop means it's obvious what other %age crops mean.

It is not immediately obvious that a 50% crop is NOT what xroxer says; it's half of an image [not sure WHAT half, but the simple definition is that it is cropping to half of the original image size]. It's not even obvious after I think about it really hard. I can't imagine it being anything else...

Until this thread I'd never seen the expression 50% crop. That's because, I imagine, that the idea has no practical utility.

Which brings us back to what does the term "100% crop" mean?

It means (as xroxer has acknowledged throughout) a crop - part rather than all of - from an image viewed at 100% in pixel terms - that is, each image pixel gets one sensor pixel. Another way of saying it is full resolution but that takes longer to type.

This, of course, has great practical utility. People are always posting 100% crops here to illustrate some point about full-resolution images without posting the whole image at full resolution.

But, Gerry...there is no way to make a 1-for-1 pixel transmission. DPR resizes every crop [within limits], so there is no way to post a 100% crop.

On my computer, where I have control of things, I don't get a 1-for-1 pixel display unless I specifically ask for it. Not all editors or display apps have this ability. And when I do, it's not close to what we see on DPR. AFAIK, DPR doesn't have a 1:1 viewing facility.

I may be missing something? Is there a way for me to send an image to DPR and have it display at 1:1 on every monitor out there? If not, then the idea of a 100% crop is silly because the 100%ness gets lost in transmission.

 

[chuxter]

I can't recall seeing reference to such a circumstance as a 50% crop.

If there are only 100% crops, then what is the "100%" for? If all crops are 100% crops, why not just call them "crops"? :-0

I know there are other kinds/sizes of crops, but I don't know what you "100% crop" folks call them?

I'm dyin' to know...