Effects of Software/Broweser/Website

[Stub Mandrel]

I'm going to upload a test image. It's not particularly goo, which is the point - it has a noisy background.

I'm then going to view it in several different programs, and on here, and take screenshots. This will eliminate any monitor differences and show if there are differences in how various programs display the same file.

[Stub Mandrel]

OK, here are the results. All these images are PNG so lossless comprssison.

Astra Image:

 

Firefox:

Paint Shop Pro:

Photoshop:

SGL (i.e. the image in the first post):

Windows Photo Viewer:

PhotoPaint:

 

[Stub Mandrel]

WOW!

The preview images showed very small differences, but once uploaded to SGL these differences have become huge!

Here's a comparison of two histograms (before uploading). Obviously some difference may be down to cropping, but...

 

[Aussie Dave]

I'm glad you did this test Neil. Any tests on facebook? I suspect it to be similar to SGL. From what I remember the older version of the SGL forum didn't have this issue, or was less noticeable.

[Aussie Dave]

I've also just noticed something. My avatar seems to be brighter. Maybe this has been an upgrade to the SGL code somewhere along the way.

[Stub Mandrel]

To round things off, the original image adjusted do it should look half-decent on here.

It's an annoyance to me that my carefull-honed(!) images look far noisier when uploaded to SGL.

[Grant]

It looks like you are just comparing the thumbnails that SGL generates - these are a resized version of the original image to make it fit within the page bounds of the forum. Do you still see the issue with the original, full size version of the image?

E.g. for the one above:

https://stargazerslounge.com/uploads/monthly_2017_04/NGC2903.png.a69793a7af4946ece2dcfb2245297928.png

I'll double check the thumbnail settings but I am pretty sure we have this set to the highest quality.

[Stub Mandrel]

22 minutes ago, Grant said:

It looks like you are just comparing the thumbnails that SGL generates - these are a resized version of the original image to make it fit within the page bounds of the forum. Do you still see the issue with the original, full size version of the image?

E.g. for the one above:

 

I'll double check the thumbnail settings but I am pretty sure we have this set to the highest quality.

It's interesting.

The SGL full-res does look better and darker, certainly better than the original looks when I display them both in photopaint on a pixel to pixel comparison!

I think the SGL preview images must exaggerate background noise, thereby exaggerating the difference between marginal images (like mine) an the really good ones.

To be honest I only click to see full res on a small proportion of images because of the time they take to display (2 meg connection).

It is clear that different packages do display images in different ways.

I have started looking into colour profiles - it's clear that the 'advanced' programs can make huge changes to the appearance of images to compensate for the end use, but how to use these? for example Photoshop can change the gamma and boost the saturation of monitor images quite apart from the colour profile used for rendering.

 

An aside, I work in publishing and 'retouched' photos sent to me look awfully over-saturated and garish when displayed on my PC, but look fine when printed.

[The Admiral]

I think it also needs to be remembered that some applications are colour managed, and others not. And that includes browsers. So if you produce an image in, say, the sRGB or the Adobe, colour space and the application isn't colour managed (i.e. takes account of the colour profile), then the appearance will not be predictable. Similarly, if your monitor is colour calibrated, I'm not sure whether all applications will use the monitor profile for display. I don't think that will account for all the differences though Neil, but it's certainly a big issue for reproduction work. Quite a minefield!

Ian

Edit. Ah, I see you're on to that one!

[Stub Mandrel]

It's boggling my brain!

I did recalibrate my monbitor a week ago.

This is useful:

http://cameratico.com/tools/web-browser-color-management-test/

I have ICCV2 and not ICCV4 according to the top two tests.

Ihe two bottom tests show no difference, showing I have good gamut and proper handing of web colours (I think).

 

AHA!

I loaded a colour management addon for firefox, and told it to use the calibrated colour profile from last week, and Lo! The images above now look darker and the noise is less objectionable. Or I'm imagining it...

I want to tell Photoshop to use the profile but the folder browser can't find the 'spool' folder in Wisystem32 although Firefox can...

I hat computers!

[Stub Mandrel]

Well this has got me playing with PSP.

Like PhotoPaint (also |Corel) it displays a much lighter image than Photoshop.

But it has some neat tricks that PS hasn't got - I'm keen to see how this will look when uploaded. If it has a 'brown & noisy' background I need to go back to the drawing board...