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Graham_of_Rainham
6th October 2015, 04:04 PM
There are often debates about the size an image should be for posting on the web. But with so many different screen sizes, resolutions, etc., what would be an optimum *???

There is a very big problem when viewing digital pictures on screens, that hardly ever gets considered.

Resolution matching...

If I post an image at 1024x768, it will look different on different screens, depending on the way the screen is setup and even which web browser I use.

I have a standard 1920x1080 monitor, with Firefox set at 100% scaling. If I have the window set at full screen my image should be around 253mm wide by 190mm high at the pixel pitch of my monitor; it often isn't.

Some people may well have their browsers set to different magnifications and will see varying sizes.

If I view the image with an Image Viewer, the pixel matching is 1:1 and the image is the exact size on the screen that it should be.

However; If I view that same image in a window on this forum the scaling is not 100%. The effect of the re-scaling can and will have an effect on the perceived image quality. Altering the window size can have differing effects depending on how the graphics board works with the browser and the web sites control systems for the various elements within the windows.

Have you ever noticed that the size of the adverts and banners don't change when you alter a window size :rolleyes:

I hear this a lot at clubs that I visit. The resolution of the monitors at their homes is different to that of the projector used at the club (1400x1050) and often they say it does not look as good.

SO: What size is this on your screen *???

http://fourthirds-user.com/galleries/data/500/4_x_3_inch_at_screen_dpi_WonB.jpg (http://fourthirds-user.com/galleries/showphoto.php/photo/29952)


WARNING: DO NOT USE A STEEL RULE TO MEASURE THINGS ON A SCREEN

Steambuff
6th October 2015, 04:32 PM
On my Dell SP2009W & 2007WFP set at 1680 x 1050 it is 4 3/16 x 3 1/8

(A lot smaller on my iPad of course ... and even smaller on my iPhone)

Dave

IainMacD
6th October 2015, 05:26 PM
105x85mm on my 1680x1050 resolution screen

Greytop
6th October 2015, 05:32 PM
95 x 72mm (give or take) on my 2560 x 1440 res screen.

Edit: Should have mentioned that its a Samsung S27B970 27 inch screen.

Ralph Harwood
6th October 2015, 05:48 PM
Hi there Graham!

On my Dell laptop with a 15.6" 1920x1080 screen it is showing as 2 3/4" by 2 1/8", using Chrome set at 100% zoom.

Cheers,

Ralph

peak4
6th October 2015, 07:30 PM
Using Maxathon browser set @ 100%
125 x 84 mm on my 1680 x 1050 HP2310i
and
121 x 91 on my 1024 x 768 Dell ultrasharp, both on the same PC as a dual monitor setup.

That is regardless of the window size, provided it's big enough to display the whole rectangle.

It does explain why people look a different shape on the two different monitors.

Couldn't tell you on the other PC as it's boxed up ready for a warranty repair collection. :(

p.s. same sizes using Firefox, Safari, Internet Explorer, and Opera, but it looks quite strange when you overlap the window across the two monitors, as the box is taller on the smaller screen.

Ralph Harwood
6th October 2015, 09:18 PM
Hi there Graham!

On my work pc it is 4 1/4" by 3 3/16" on an HP L1750 17" 1280x1024 screen, using chrome at 100%.

Graham_of_Rainham
6th October 2015, 09:58 PM
Previously I said: If I view the image with an Image Viewer, the pixel matching is 1:1 and the image is the exact size on the screen that it should be.


But that only applies for my monitor with a Pixel Pitch of 0.2475 mm

I use this pixel pitch to set the monitor dpi to 102.626 in Photoshop, so that my images are the correct size on the screen. Doing this, for me, makes for a better assessment of the image quality as I am looking at 1:1 pixel mapping and not some arbitrary re-sized image that may contain artifacts generated by the re-size processing.

Zuiko
6th October 2015, 11:18 PM
Oh dear, on my screen it is 6 x 4.5 inches! :eek:

bilbo
7th October 2015, 09:59 AM
5" x 3.75" in IE at 100%

Graham_of_Rainham
7th October 2015, 10:06 AM
Oh dear, on my screen it is 6 x 4.5 inches! :eek:

The real time to worry is when it's no longer a 4:3 ratio. I've actually seen some images that have oval wheels, where people haven't used "Preserve Aspect Ratio" :o

Naughty Nigel
7th October 2015, 01:11 PM
95 x 72mm (give or take) on my 2560 x 1440 res screen.

Edit: Should have mentioned that its a Samsung S27B970 27 inch screen.

Same on my Iiyama 27" screen using IE at 100%.

I believe my monitor uses the same panel as yours (as does the 27" Mac monitor).

OM USer
7th October 2015, 04:13 PM
3.2" x 2.4" on my 17" 1920x1080 laptop
4" x 3" on my Samsung 22" 1920x1080 monitor
both using Firefox 100% scaling and image does not change size as I change the window size.

Kiwi Paul
7th October 2015, 04:32 PM
4 1/4" x 3 3/8" on a 24" 1920 x 1080 HP monitor offshore and 3 1/2" x 2 1/2" on my Dell laptop 15" 3200 x 1800 both using Chrome at 100%

Paul

Graham_of_Rainham
7th October 2015, 05:00 PM
One of the main reasons for having the image on the screen or print being the correct size, comes from undertaking and reporting on defects. In addition to placing a forensic scale ruler in the shot, reproduction at life size (where possible) was required.

While most systems faithfully reproduce the pixel count, getting those pixels to display at the right size on the screen or print takes that bit more time and effort.

Projected images are virtually impossible to get the size right in all but a fixed dedicated presentation suite. Fortunately people readily accept larger than life images on the big screen.

The amount of variation in the sizes you have reported here, is entirely as I expected.

Life was so much simpler with film and 10"X8" prints. :rolleyes:

Dewi9
7th October 2015, 08:10 PM
Using Firefox on my HP LA2306x (1920 x 1080) I get 4.3" by 3.2" (in old money).

David

IanB
7th October 2015, 10:09 PM
100 x 75mm = 4 x 3 inches

same size screen [Dell] as Graham's and I use Chrome

However at 100% and with my screen set to high resolution the type is too small. Bit to do with born too long ago I guess. Type is sharp enough; just too small for my liking

Just for interest I will set the font on this line to that suits me with the screen at 100% (size 3

And I prefer the darker font
Just for interest I will set the font on this line to that suits me with the screen at 100% size 4

Thanks for the thread Graham; good forum management *chr

IanB
7th October 2015, 10:33 PM
RE font size: I should mention my reading/writing/typing is not the best and I'm dyslexic so the bigger and darker size preferences is to over come some of those short comings and frustrations. Typing/reading this on a 100% screen is near impossible for me.

The last bit is so much better for; however I don't expect this forum or any forum to be set to how I like; unless others can see the need also

Graham_of_Rainham
8th October 2015, 09:27 AM
I use Firefox, which has in the options the ability to change the browser font (size, type, colour, etc.) to whatever you want. Just have to uncheck the box that says:

"Allow pages to use their own fonts", in the Advanced options.

I don't know if other browsers have this, I expect they would.

That way you can have the window at 100% or whatever suits you and the text at whatever size best fits that.

*chr

Ross the fiddler
8th October 2015, 10:28 AM
My HP 17" (ProBook) laptop is 1600 x 900 & I like to view the page at 110% using G'Chrome which shows that box as 4 1/4" X 3 3/16" (108 x 80.5 mm).

Sorry, I used a steel ruler! :p

IanB
8th October 2015, 09:51 PM
Sorry, I used a steel ruler! :p

your measurements will be different due to ours/their temperature being different; we need to take the metal expansions into the equation :rolleyes: :D

raichea
8th October 2015, 10:59 PM
SO: What size is this on your screen *???


Not intended to be controversial, but I'm not sure I get the point here... The browser only knows about pixel dimensions. There's no attempt by the browser to try and make the image exactly 4"x3"... it simply displays it at 1:1 pixel ratio unless the user has changed the zoom factor, or the HTML for the page tells the browser to scale the image for display to fit a particular set of pixel dimensions.

Graham_of_Rainham
9th October 2015, 12:01 PM
Not intended to be controversial, but I'm not sure I get the point here... The browser only knows about pixel dimensions. There's no attempt by the browser to try and make the image exactly 4"x3"... it simply displays it at 1:1 pixel ratio unless the user has changed the zoom factor, or the HTML for the page tells the browser to scale the image for display to fit a particular set of pixel dimensions.


Indeed a 1024x768 image will be displayed with a 1:1 ratio at 100%. Or at least it should be. But as counting pixels is difficult, a simple way to see if the monitor is correctly displaying the image at a 1:1 ratio is to have a known size image and the right number of pixels to match the pixel pitch of the monitor. When you display a RAW image it is much bigger than most monitors will show at 100% so we zoom down or "scale to fit". Often zooming in and out to assess detail, etc.. By having photoshop set to the correct pixel pitch the zoomed image is faithfully displayed.

This was first noticed when most screens were 72 ppi and the newer screens 96 ppi. People started to comment on the different "look" of images. Most often this was seen when people had a bigger better monitor at home than the one on the laptop at the camera club.

Many will be perfectly happy working with the default settings in the editors and image viewers and actual size will be of no consideration. After all it's what it looks like to you and how you prefer to have it displayed that is by far the most important factor..

OM USer
9th October 2015, 05:18 PM
I'm sure Windows NT4 came with a display scaling option which put up a ruler on the screen and you could adjust the scaling until the markings on the on screen ruler matched a real one held up to it. I can't find any such option in 8.1.

pandora
9th October 2015, 07:40 PM
It is 4" x 3" on my laptop screen resolved at 1366 x 768

But thanks for raising this often overlooked issue.