Ruler program for Mac

I think in the old days this would have been a reasonable approach (to have a piece of software to do the work) as the dpi for monitors was reasonably standard. Nowadays, not so much as monitor dpi varies greatly and is very high in some cases (Retina screens)
 
sphexx said:
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 :(.
Click to expand...

Yes I do, and indeed photographs often include a scale, or photographed on a cm graph paper etc. But you can also often scale things from known sizes. That's what I meant by proportions in one of my earlier posts. e.g. for large scale images, you might have a recognisable make and model of car that you can find out the length of. Or include metre sticks across a landscape.

There are better tools than a ruler to do this with, but a simple ruler still gives an easily accessible first look. But I also do other things where I would find a ruler useful.
 
Phil V said:
You could do that with most image editing programs. Certainly photoshop would make it simple.
Click to expand...
Yes, but I want something free floating to use across programs. I have several options available, its the flexibility of quick access to a measuring device that is attractive
 
Pound Coin said:
I think in the old days this would have been a reasonable approach (to have a piece of software to do the work) as the dpi for monitors was reasonably standard. Nowadays, not so much as monitor dpi varies greatly and is very high in some cases (Retina screens)
Click to expand...
All the options I've found need calibrated to the monitor. Which I admit I was hoping to avoid, in my ignorance, I assumed the software would read the screen resolution and self calibrate, but they don't seem to do this.
 
myotis said:
All the options I've found need calibrated to the monitor. Which I admit I was hoping to avoid, in my ignorance, I assumed the software would read the screen resolution and self calibrate, but they don't seem to do this.
Click to expand...
Some of them seem to do that https://www.piliapp.com/actual-size/inch-ruler/ on my iPad detects that it is a 10.5 in screens and sizes the ruler accordingly. Of course it’s not floating (and iPad) so no good to you.
 
To be honest, I think your best solution is the one you currently use, ie, a ruler on the screen. The next stage may be to print an acetate with horizontal and vertical lines at “real” inches, but again that would mean holding the acetate against the screen. I’m not aware of an overlay program, but I thought might help others to understand what you need - if indeed my assumption is correct!
 
Stephen L said:
To be honest, I think your best solution is the one you currently use, ie, a ruler on the screen.
Click to expand...

Thanks. That's what I've done until now, as "proper measurements" are done in ImageJ, QGIS, or Photoshop. But I have a range of things I do where a quick and dirty measurement on the screen with a ruler is enough for what I want, and the easiest/quickest way of doing it.

I've known for years that on-screen ruler programs exist, often mentioned in tutorials on web design etc, and I have always meant to install one.

On Friday, I couldn't find my physical ruler, and I thought this was the sign to finally download an on-screen ruler. Only to find there are dozens and dozens of options. I thought I would save myself a bit of heartache and time by simply asking about what other people use.

In the end, I think I am going go for something a bit more sophisticated than just a ruler, as I've found programs with some extra features that could be useful.

Ondesoft Ruler https://www.ondesoft.com/rulers/ is self calibrating but I can 't get it to work on dual monitors (I have emailed support, but no reply yet. but it was/is weekend/holiday period).

Pixelshift https://plumamazing.com/product/pixelstick/ needs calibrated (I've done that now with the trial), but it doesn't show a ruler, just a line that you can preset to a specific size, or drag to make measurements.

I may well buy both, as they offer different feature sets beyond their basic measurement tools.
 
Since you posted originally I’ve been practising and I’ve found the screen grab system (which I have on a button on my mouse) to be an easy way to get pixel measurements and then use the Calculato app with the relevant factor set in memory to convert to inches etc. A real calculator would be better probably. In the car example you gave it would be particularly easy to measure the car in pixels and then the ‘unknown’ to get a proportion.

Since you mentioned beetles earlier I’ve been thinking that ants would probably have a novel solution to this problem given time — millennia unfortunately ;) — but it’s probably beyond beetles :(.
 
sphexx said:
Since you posted originally I’ve been practising ...

Since you mentioned beetles earlier I’ve been thinking that ants would probably have a novel solution to this problem given time — millennia unfortunately ;) — but it’s probably beyond beetles :(.
Click to expand...

Impressed to see you are still thinking about this, especially the idea of posting the problem on a forum populated by ants rather than photographers :)

However, as you suggest, I suspect the wait for an ants solution might not come quick enough for me, and as I mentioned in my last post, I'm just going to buy one of, or both, pixelstick and ondesoft rulers.
 
myotis said:
Impressed to see you are still thinking about this, especially the idea of posting the problem on a forum populated by ants rather than photographers :)

However, as you suggest, I suspect the wait for an ants solution might not come quick enough for me, and as I mentioned in my last post, I'm just going to buy one of, or both, pixelstick and ondesoft rulers.
Click to expand...
I was going to write that I am a longtime formiciplile but having made up the word, as I thought, it turns out that formicophilia is a thing and not at all what I meant - https://en.m.wikipedia.org/wiki/Formicophilia :( and come to think of it any attempt to play on the hymen in Hymenoptera will probably lead down a similar path.
 
Last edited:
You must log in or register to reply here.
Back
Top