Ruler program for Mac

myotis

myotis

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Graham
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Can anyone suggest a ruler program to measure image sizes in inches, cm and pixels that will run on a Mac.

Happy enough to pay for one, but would appreciate a recommendation.

Thanks.
 
I'm not really understanding as image size really depends on the PPI it's output at.

The LR print module can measure in inch/cm and display the corresponding PPI as it is resized.
 
sk66 said:
I'm not really understanding as image size really depends on the PPI it's output at.

The LR print module can measure in inch/cm and display the corresponding PPI as it is resized.
Click to expand...

Thanks, but you may be thinking too deeply about this. I'm really just looking for for something that will make it easy to measure image sizes on the screen, rather than resting a ruler on the monitor.

Its just that most of the tools I've found also calculate the number of pixels within an image, which I thought might be useful, but its the ruler feature I really want.
 
If measuring in screen pixels is enough, you can just use the screen grab tool (shift+cmd+4)... press escape to not take the grab. It wouldn't be hard to apply a conversion factor to get inch/cm/etc if you really needed...
 
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Interesting problem. Like Steven, I’m having difficulty understanding what you want to do, or rather the “why” would be more helpful. I have had to do this recently where I converted a photo to a graphic and needed to print the result so that an added circle was 1 inch in diameter so I inserted the image into Apple Pages where I could resize it to exact measurements. Not sure that will help you though, it all depends on the “why” :(.
 
sk66 said:
If measuring in screen pixels is enough, you can just use the screen grab tool (shift+cmd+4)... press escape to not take the grab. It wouldn't be hard to apply a conversion factor to get inch/cm/etc if you really needed...
Click to expand...
I'm looking for something that is easier than physically putting a ruler against the monitor, as I said the pixels just seemed a useful addition. Among, other things, I want to be able to adjust images on screen so they are an exact size e.g 5" long.
 
sphexx said:
Interesting problem. Like Steven, I’m having difficulty understanding what you want to do, or rather the “why” would be more helpful. I have had to do this recently where I converted a photo to a graphic and needed to print the result so that an added circle was 1 inch in diameter so I inserted the image into Apple Pages where I could resize it to exact measurements. Not sure that will help you though, it all depends on the “why” :(.
Click to expand...

Thanks, I have a few different uses, where I currently physically put a ruler on the monitor, and I just wanted a suggestion for an application that would make it easier (and more accurate) to make measurements than using a plastic ruler, but that is all I want, a digital equivalent of 12" ruler. For example I sometimes want an image that is an exact dimension on screen, or to measure things on the screen to calculate proportions from online images.

I'm sorry this seems to have become so complicated, there are so many ruler applications available, that I was hoping for responses that would through up some consensus on which one to buy.
 
There’s the ‘Measure’ app in iOS 12 where you use the iPhone/iPad as a virtual ruler measuring things remotely (so it’s the equivalent of holding the ruler to the creek but at a distance) though I’m not sure that would work for you.
 
sphexx said:
There’s the ‘Measure’ app in iOS 12 where you use the iPhone/iPad as a virtual ruler measuring things remotely (so it’s the equivalent of holding the ruler to the creek but at a distance) though I’m not sure that would work for you.
Click to expand...

Thanks, I don't think my old IOS devices will run this, but it also seems to need you take a photograph with an IOS device rather than it measuring existing images on my Mac.

But I'm not short of apps to try, (e.g. https://www.ondesoft.com/rulers/) just trying to benefit from the experience of others, but so far it's obvious no one has used any, or even know what I'm talking about :-)
 
myotis said:
I'm looking for something that is easier than physically putting a ruler against the monitor, as I said the pixels just seemed a useful addition. Among, other things, I want to be able to adjust images on screen so they are an exact size e.g 5" long.
Click to expand...
If you use the screen grab function it tells you the size of area (length/width) selected in display pixels. On my MBPr set to the default display resolution (1440x) that equates very closely to 4px/mm or 100px/in (4.01/101 exactly).
Which means the reply button below is pretty much exactly 1inch on my display because it measures 101px wide. I even made a video for you...

View: https://youtu.be/NMfVFnTW-hI
 
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sk66 said:
If you use the screen grab function it tells you the size of area (length/width) selected in display pixels. On my MBPr set to the default display resolution (1440x) that equates very closely to 4px/mm or 100px/in (4.01/101 exactly).
Which means the reply button below is pretty much exactly 1inch on my display because it measures 101px wide.
Click to expand...
Thanks, for the effort, but this seems like more work, rather than less work, than just using a physical ruler, to adjust an image so it's exactly 5" long on screen.

It looks as if I can't avoid downloading and comparing a selection of on screen ruler programs :-(
 
myotis said:
Thanks, I don't think my old IOS devices will run this, but it also seems to need you take a photograph with an IOS device rather than it measuring existing images on my Mac.

But I'm not short of apps to try, (e.g. https://www.ondesoft.com/rulers/) just trying to benefit from the experience of others, but so far it's obvious no one has used any, or even know what I'm talking about :)
Click to expand...
You don’t take a photo with Measure but it uses the camera and you tap the end points you wish to measure and it ‘knows’ the distance from camera to them and can triangulate. I’ve only played with it and it’s pribably more for room measurements etc.
I think Steven is right about the screen grab as I use that all the time (maps in browser windows) though I usually the use Preview and annotate and save them.
 
myotis said:
Thanks, for the effort, but this seems like more work, rather than less work, than just using a physical ruler, to adjust an image so it's exactly 5" long on screen.

It looks as if I can't avoid downloading and comparing a selection of on screen ruler programs :-(
Click to expand...
Uhm... since 101px = 1" on my screen I would just make the image 505px long with any image resizing tool...
 
sphexx said:
I think Steven is right about the screen grab as I use that all the time (maps in browser windows) though I usually the use Preview and annotate and save them.
Click to expand...

This still seems complicated when all I want is a ruler that I can quickly move around the screen.

Having said that, this one looks promising. https://plumamazing.com/product/pixelstick/

It doesn't actually have an onscreen ruler, but you can set up the line to a specific length, and the other features give some useful tools beyond a simple on screen ruler.
 
sk66 said:
Uhm... since 101px = 1" on my screen I would just make the image 505px long with any image resizing tool...
Click to expand...

But, I did say that I have multiple things that I currently measure with a physical ruler, that was just one example. I really do just want a digital ruler, though as I said in my last post, this looks promising https://plumamazing.com/product/pixelstick/ and better than the program that I suggested in an earlier post.

Its more than just a ruler, but overall it offers features that seem well suited to the range of things I want to measure.
 
Yes, I’ve just been reading it web site and can’t see how it does what you want — without buying and trying it, which I’m not going to do ;)
 
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I’ve used Xscope, I’d need to check if it does inches, but it would have to know what dpi the monitor was. It is spendy; I’ve had it since the early days and used it for web and screen design.

EDIT: it measures in Pixels and Points.
 
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sphexx said:
Yes, I’ve just been reading it web site and can’t see how it does what you want — without buying and trying it, which I’m not going to do ;)
Click to expand...

While it doesn't have a physical replica of a ruler on screen, it does have a line that you can drag from one side of an image to the other side of it, with a read out of how long the line is.

OR, you can preset the line to a specific length and then adjust an image size to match the length of the line.
 
sphexx said:
This http://www.pascal.com/software/freeruler/ gives a floating ruler but I haven't worked out how to calibrate it to actual measurements :(
Click to expand...

Thanks for the effort your putting into this, but I've already found these, and many others. The point of my post was that given I was finding so many options, many when you follow them up turn out to be dead links or last updated many years ago, that I was hoping to find someone who was actively using something they knew still worked.
 
Pound Coin said:
I’ve used Xscope, I’d need to check if it does inches, but it would have to know what dpi the monitor was. It is spendy; I’ve had it since the early days and used it for web and screen design.

EDIT: it measures in Pixels and Points.
Click to expand...
Thanks, I found this but was put off a bit by the price, which was a bit more than I wanted to spend. Interesting it still only gives pixels and point. I was rather hoping for something that would self calibrate to the screen resolution and give cm and inches , but everything I've found so far needs calibration
 
myotis said:
Thanks, I found this but was put off a bit by the price, which was a bit more than I wanted to spend. Interesting it still only gives pixels and point. I was rather hoping for something that would self calibrate to the screen resolution and give cm and inches , but everything I've found so far needs calibration
Click to expand...

There's no way to auto calibrate - even if you did know the resolution, the pixel density of the display / monitor size, there are additional settings in the monitor to align, grow / shrink the screen etc and these are not readable by the system.
Like others I'm struggling to understand what you are looking to use the measurements for? There may be an easier solution if we understand that.
 
myotis said:
Thanks for the effort your putting into this, but I've already found these, and many others. The point of my post was that given I was finding so many options, many when you follow them up turn out to be dead links or last updated many years ago, that I was hoping to find someone who was actively using something they knew still worked.
Click to expand...
It’s an interesting problem but like David I feel you may need to think outside the box since we can’t see what your object is in doing this .:thinking:
 
myotis said:
Thanks, I found this but was put off a bit by the price, which was a bit more than I wanted to spend. Interesting it still only gives pixels and point. I was rather hoping for something that would self calibrate to the screen resolution and give cm and inches , but everything I've found so far needs calibration
Click to expand...

But that’s the point.

Your understanding of the size of a screen object appears to be flawed, your 5” image isn’t carved in stone anywhere, and that image would be 6 different sizes just on my products. Any image that you see now as 5” could easily be different in a second or 2. The 5” is a calculation of pixels divided by output resolution. It’s not ever been or will it ever be a 5” image except in that moment on your Mac.

Perhaps if you told us what problem your really trying to solve, we could help.
 
I cannot for the life of me fathom out what is trying to be achieved here.

why not open the image in preview, go to tools and type in the size you want in mm, cm, inches or whatever and it will be automatically set to that size.
 
sphexx said:
It’s an interesting problem but like David I feel you may need to think outside the box since we can’t see what your object is in doing this .:thinking:
Click to expand...
I just want to measure things on screen, which I currently use a physical ruler for, and as I was aware of on-screen rulers, it was suggestions for an on screen ruler I was asking about.

I thought it was a simple question, not a particularly interesting one, not one that required any out the box thinking, not one that required any detailed explanation, nor one that need me to explain the multiple things I measure on the screen, because, as I saw it, I just wanted a simple on-screen ruler. However, having looked at the extra features that programs like pixelshift offer, and that everything I've found seems to need calibration, I may well go for something more sophisticated than a simple ruler.

The on screen rulers you linked to were exactly the type of program I was looking for. But the point of posting wasn't to get someone to repeat the search I had already done and re-find the programs I had already found, but to try and benefit from peoples' experiences, because as I said, there are dozens of these types of programs available, and my hope was for help in identifying one that people were already happily using.

So, I was hoping for something like " I used to use x, which was free, but I now use y, which although not free, was worth the money because it crashes less often and it allows me to measure angles, which may or may not be useful to me" Or "I used to use program x, but since upgrading to High Sierra, it's stopped working and hasn't been updated for 5 years, I'm now using X".

I still appreciate, the effort you and David have gone to, but I really did think it was a simple question, that would have been easy to answer, or just ignored.
 
myotis said:
I just want to measure things on screen, which I currently use a physical ruler for, and as I was aware of on-screen rulers, it was suggestions for an on screen ruler I was asking about.

I thought it was a simple question, not a particularly interesting one, not one that required any out the box thinking, not one that required any detailed explanation, nor one that need me to explain the multiple things I measure on the screen, because, as I saw it, I just wanted a simple on-screen ruler. However, having looked at the extra features that programs like pixelshift offer, and that everything I've found seems to need calibration, I may well go for something more sophisticated than a simple ruler.

The on screen rulers you linked to were exactly the type of program I was looking for. But the point of posting wasn't to get someone to repeat the search I had already done and re-find the programs I had already found, but to try and benefit from peoples' experiences, because as I said, there are dozens of these types of programs available, and my hope was for help in identifying one that people were already happily using.

So, I was hoping for something like " I used to use x, which was free, but I now use y, which although not free, was worth the money because it crashes less often and it allows me to measure angles, which may or may not be useful to me" Or "I used to use program x, but since upgrading to High Sierra, it's stopped working and hasn't been updated for 5 years, I'm now using X".

I still appreciate, the effort you and David have gone to, but I really did think it was a simple question, that would have been easy to answer, or just ignored.
Click to expand...


People understand the question, they don't understand why measuring something on a screen with a ruler can be of any use for anything, and were hoping for an explanation (beyond "I want to measure something on my screen with a ruler").
 
What Phil says +1 :( and Ned +1 .
 
Phil V said:
Perhaps if you told us what problem your really trying to solve, we could help.
Click to expand...

Canon f1.8 said:
I cannot for the life of me fathom out what is trying to be achieved here.
.
Click to expand...

While I appreciate the responses, this has become horribly complicated.

I make measurements on screen for multiple purposes (including biological, and cartographic as well as occasionally photographic), with images displayed in a range of different programs currently the measurements are often made with a physical ruler held against the screen.

There are dozens of on screen rulers and measurement tools available, many recommended for graphic design purposes (hence my assumption there might be some users on this forum) as well as scientific uses, and I just want to replace my physical ruler with an on-screen one.

Many of the available programs seem to be old (but may still work fine), and as its such a simple tool, and they all look similar so it may not matter which one I use, but again there may well be one particular program which is recognised as "the best" or it may be that all the low cost or free programs have issues and people have learnt its worth while paying for something better

I did think this was a very simple question and that only people who used on-screen rulers would respond to it. I didn't think it needed any explanation of all the uses I put a ruler to, as it seemed straightforward that I just wanted some help in choosing between the many on screen ruler programs that are available.

I appreciate, maybe because people are unfamiliar with on-screen rulers, that there has been an effort to identify a specific problem, to try and find a solution, but I really do just want an on-screen ruler program.
 
There’s nothing biological on a screen that you could measure with a ruler ... except maybe fungus or arguably OLED screens ;) so I’m guessing you mean images of a biological nature - bats perhaps from your username - but the ruler would have to be in the original image to be of any use so I’m still struggling :thinking: :thinking::thinking: to see it :(.
 
myotis said:
While I appreciate the responses, this has become horribly complicated.

I make measurements on screen for multiple purposes (including biological, and cartographic as well as occasionally photographic), with images displayed in a range of different programs currently the measurements are often made with a physical ruler held against the screen.

There are dozens of on screen rulers and measurement tools available, many recommended for graphic design purposes (hence my assumption there might be some users on this forum) as well as scientific uses, and I just want to replace my physical ruler with an on-screen one.

Many of the available programs seem to be old (but may still work fine), and as its such a simple tool, and they all look similar so it may not matter which one I use, but again there may well be one particular program which is recognised as "the best" or it may be that all the low cost or free programs have issues and people have learnt its worth while paying for something better

I did think this was a very simple question and that only people who used on-screen rulers would respond to it. I didn't think it needed any explanation of all the uses I put a ruler to, as it seemed straightforward that I just wanted some help in choosing between the many on screen ruler programs that are available.

I appreciate, maybe because people are unfamiliar with on-screen rulers, that there has been an effort to identify a specific problem, to try and find a solution, but I really do just want an on-screen ruler program.
Click to expand...

Coming from an IT background, I’m struggling to think of a display I’d trust to measure with a ruler, it might work for comparison purposes, but if I wanted to know the size of a screen object, I’d be expecting to pay for software that was absolutely certain it knew the specifications of my screen.
 
Phil V said:
Coming from an IT background, I’m struggling to think of a display I’d trust to measure with a ruler, it might work for comparison purposes, but if I wanted to know the size of a screen object, I’d be expecting to pay for software that was absolutely certain it knew the specifications of my screen.
Click to expand...


Or in the days that I used to use biological imaging systems, calibrated to the camera...
 
Nawty said:
People understand the question, they don't understand why measuring something on a screen with a ruler can be of any use for anything, and were hoping for an explanation (beyond "I want to measure something on my screen with a ruler").
Click to expand...

Does it really matter, in terms of my question on choosing an onscreen ruler.

But as an example, although most of the time I'm working in programs with proper measurement tools, sometimes for speed, If I have a photograph of ten beetles and 20 seeds etc that includes a 100mm scale. I adjust the photograph size until the 100mm scale in the photograph is 100mm on the screen and then take direct measurements of the beetles or seeds with a ruler.

Or sometimes I want to resize multiple images on the desktop which have all been taken at different scales and I want them all to be at the same scale, or occasionally all at the same size (regardless of file resolution)

I just have occasions where an on screen ruler would be a useful thing to have available.
 
myotis said:
Does it really matter, in terms of my question on choosing an onscreen ruler.

But as an example, although most of the time I'm working in programs with proper measurement tools, sometimes for speed, If I have a photograph of ten beetles and 20 seeds etc that includes a 100mm scale. I adjust the photograph size until the 100mm scale in the photograph is 100mm on the screen and then take direct measurements of the beetles or seeds with a ruler.

Or sometimes I want to resize multiple images on the desktop which have all been taken at different scales and I want them all to be at the same scale, or occasionally all at the same size (regardless of file resolution)

I just have occasions where an on screen ruler would be a useful thing to have available.
Click to expand...
You could do that with most image editing programs. Certainly photoshop would make it simple.
 
Phil V said:
Coming from an IT background, I’m struggling to think of a display I’d trust to measure with a ruler, it might work for comparison purposes, but if I wanted to know the size of a screen object, I’d be expecting to pay for software that was absolutely certain it knew the specifications of my screen.
Click to expand...

I'm just looking for something quick and dirty for occasional use, across a range of uses, and obviously just hoping for a simple suggestion of an on-screen ruler that someone had experience of using.
 
myotis said:
Does it really matter, in terms of my question on choosing an onscreen ruler.

But as an example, although most of the time I'm working in programs with proper measurement tools, sometimes for speed, If I have a photograph of ten beetles and 20 seeds etc that includes a 100mm scale. I adjust the photograph size until the 100mm scale in the photograph is 100mm on the screen and then take direct measurements of the beetles or seeds with a ruler.

Or sometimes I want to resize multiple images on the desktop which have all been taken at different scales and I want them all to be at the same scale, or occasionally all at the same size (regardless of file resolution)

I just have occasions where an on screen ruler would be a useful thing to have available.
Click to expand...

It's only because we are interested :)

Phil V said:
You could do that with most image editing programs. Certainly photoshop would make it simple.
Click to expand...

Which is why we are all a bit nonplussed.
 
Phil V said:
You could do that with most image editing programs. Certainly photoshop would make it simple.
Click to expand...

Yes, but the reason why I didn't want to go into details of what I wanted to measure is because the many different things I do all have alternative solutions, but an on-screen ruler program floating over other programs gives me a flexibility that I want.
 
Nawty said:
It's only because we are interested :)



Which is why we are all a bit nonplussed.
Click to expand...

OK, and yes I know you can measure things in Photoshop, but a floating ruler lets me be independent of any particular program.

I don't really have a problem that needs solving, I just occasionally find being able to take rough and ready measurements of things useful, and an on screen ruler program would be easier than trying to physically measure it.
 
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