How large might realistic handgun targets appear on a computer?

I enjoy target shooting, and I enjoy photography. I've recently wanted to take photos of targets, such that the target people see in a forum such as this one, appear the same size that they do to the shooter.

I'll post here what I think I need to do - if anyone an point out something I'm not considering, please do so.

Suppose I want to show a 3" target, which is 15 yards from the shooter. 15 yards can be converted to 540 inches, so I'm doing all this in the same units, inches.

My reasoning is that a 1 1/2" target, half as far away (7 yard, or about 270 inches) would look the same as a 3" target twice as far out. It's all proportional.... perspective.

If that is true, then if you're viewing this target on a computer monitor say, 14 inches away from your eyes, which is about 1/40th of the distance to the actual target, I should make the size on your computer monitor 1/40th of 3", or roughly a little less than 1/10th of an inch.

Any math genius out there who would want to confirm or correct this?


Note: this thread was prompted by my wanting to show a 14" USBR target so it would look realistic on a computer monitor - would look close to what the shooter was seeing. I did it by "guess", and got this:
...but I'd like to do it properly. What I did here is still much too big.

That's good information to work with. So, there's screen size, screen resolution, and how far away the screen is from someone's eyes.

More variables to work with. Anything else?

If I take all those factors into account, and if someone says they are looking at an xx inch monitor with yyy pixels per inch, at zz inches away from them, I can now calculate how wide (in real inches) a given target should take on their screen. With everything factored in, it's just mathematics.

Just as an example, let's say on a 15" monitor at 18 inches away from their eye, with a 1024 pixel wide monitor, it would mathematically be 1/10th of an inch. All I would need then, is an app that adjusts the zoom size for that image, such that a ruler on front of the screen would help them make the image just the right size.



(I used to know all about this sort of stuff with film photography, which focal length lens to use, and how many inches from one's eye the print had to be to replicate what the person (in this case, a camera) saw, so that both look identical. That was a lot more complicated than what I'm trying to do here.)

primalmu said:

If you're going to have to have people use a rule to adjust the page zoom... '''Again, I think your endeavor is fruitless.

Click to expand...

Nope, I didn't want to do it that way; I just want to find a way to make the image (not the screen) show up realistically.

Think of it this way. Suppose I was in a gymnasium or something similar, and I hung up a target 15 yards (or whatever) from me. Instead of my shooting gear, I put my 15" (or whatever) laptop on the table. I then took a photo of the target, and displayed it on my laptop. I want a control, somewhere, somehow, to make the laptop screen show the target at the same size (relative to my eyes) as I then looked at the target. No larger, no smaller.

Before I even start on that, I need to define how large the target would appear to be. I suppose the next time I go to the range, I can keep drawing the outline of a target on a piece of paper, adjusting the size such that when the paper was held 15" (or whatever) in front of me, both the paper sketch, and target, appeared to be the same (to my eyes).

Twiki357 said:

I know that you can’t do it. There are to many variables from one computer to another.......

Click to expand...

I disagree. I may need to create a program/app that allows me to scale the size of any image up or down, and use that as an image viewer. I know that technically, I can do this, but I don't know if I know enough about programming to ever make a program like this. Maybe I'll find something that already does this.

There is a home design program called "Sweet Home 3D" that does this nicely - you can download and try the free version if you want. That's overkill, but I can draw my target accurately in the top box, and the lower window will allow me to scale the target to any size I want, and even to look at it from a different angle if I wish to. ......thanks - because of what you wrote, it made me think of this. Maybe that is an easy way for me to start out.

MrBorland said:

If you just want to adjust the image size, try flanking the entire

link with {resize=X]...{/resize]. The top image below is full size, where underneath it, it's been resized to x=100 (note that { should actually be a [, but it doesn't show up for some reason when I use a [ in this demo). .......

Click to expand...

Brilliant!!!!! If I calculate "X" as needed, that might be the perfect way to do what I'm looking for!!!!

I never knew of the "resize" tool....


Since people move their head in and out as they work on a computer, I don't need to do this very precisely. Maybe I can find a browser similar to one I used ages ago, that lets me type something in one window, and instantly see the result in another window.

Or, type the line in just the way you wrote it, and allow people to click on "preview post", put in a pre-calculated definition for "X" and instantly see the adjusted target as soon as they click "Preview Post". THANKS!!!!

Test

Original size image as posted yesterday:





BrBorland's test, with X=50
[resize=50] [/resize]


BrBorland's test, with X=75
[resize=75] [/resize]



BrBorland's test, with X=100
[resize=100] [/resize]



BrBorland's test, with X=1000
[resize=1000] [/resize]


Hmmm..... The "preview" command doesn't work, but the posted response is just what I wanted. I just need to use maybe "100" for targets 15 yards away, and based on all the other factors, tell people how close their eyes need to be to the screen.


MrBorland - THANK YOU once again.

Hmmm.....
using Google Chrome for a browser, it shows 4 images at different sizes.
using the old Windows Explorer (which I never use) I get 4 full-size images
using Edge, the new browser that comes with Windows 10, it shows 4 images at different sizes.
using Google Chrome on my iPhone, it shows 4 images at different sizes.

I've deleted all my other older browsers, and started using Google Chrome on all my computers and phones (which also allows me to sync all of them).

Joe_N said:

Right now I am viewing the images on an 8" tablet and they all display the same size. They all fill the screen horizontally in portrait orientation and fill the screen vertically in landscape orientation. Is that what you were attempting to accomplish?

Click to expand...

Nope. which tablet are you using? If it's Android or iPhone, just install Google Chrome for a browser. That should fix this (and any other changes that old browsers don't recognize).


..........a next step will be to add the appropriate amount of "blur", so it looks the way it does while concentrating on a gun's front sights maybe one of you can post a target photo here, so I can use your target, not mine.

PJSprog - I'd like to be able to create (and/or post) a photo that looks just like what my eye actually sees at the range, for many purposes, which now include posting here. Think of a webcam, mounted behind the rear sight. Sort of.




Sunray - yep, I've got, and use, Photoshop all the time. Yes, I can do all the above myself, but as everyone pointed out, there are too many variables.

For anyone with a recent browser, such as Google Chrome, MrBorland's suggestion does just what I wanted.

Back in my film days, with Contax, Nikon, and Leica cameras, the 50mm lens was "normal" (natural view), the 35mm was wider angle, and anything from 85mm up was considered telephoto. This was on a full 35mm image, 24mm x 36mm in size.

Now that everyone has gone digital, the 50mm lens is considered normal only on full frame sensor cameras (same sensor size as 35mm film). For other cameras, with small sensors, they usually give out "equivalent focal length", so people will be able to relate to the numbers. A 35mm lens on an ordinary DSLR with the usual sensor, not full-frame, will create an image that is similar to what a 50mm lens will get with a full frame sensor.


What most people don't realize, is that a "normal" 50mm lens will give a realistic view when an 8 x 10 print is held out at a normal viewing distance. All the other focal length lenses can also give a "normal view" when held closer or further away. Even a "fisheye" lens can create a "normal" looking image when the print is held almost directly in front of the eye. It all gets very long and complicated. That's why some people say a wide angle lens makes a room look larger. I can explain more, if anyone is interested.


Most people I meet have no interest in stuff like that. Hardly anyone seems to care any more. Just press the button and upload to whatever social site you use.....



Back to your comment - I agree. If you took a photo with a 43mm lens, and showed the resulting picture filling up the screen of a 15 inch monitor, and viewed it from a normal viewing distance from a laptop, the picture would seem very realistic, and the target would appear close to the way it appeared to someone's eye. I think a 50mm lens would make it slightly larger, making it a tiny bit more accurate.

(Of course, if I were to do that, people here in the forums would yell at me for posting such a huge photo!!! )