Upload Test - at different sizes

[rpcrowe]

I did a test to see the quality of an image when I save it in JPEG and post it to my smugmug.com site. I am wondering what the perceptible difference in quality will be...

This image was posted to smugmug at full size from the A6400 camera and linked to this posting in the "original" size of 4000 x 6000 pixels...



This image was posted to smugmug at full size from the A6400 camera and linked to this posting in the X2 size of 640 x 960 Pixels...



This image was reduced in size when I posted it to smugmug.com at 1440 x 2160 pixels and linked to this posting in the 1440 x 2160 original size...



This image was reduced in size when I posted it to smugmug.com at 1440 x 2160 pixels and linked to this posting in the X2 size of 640 x 960 pixels...



I selected this image to test because of the detail of her costume...

[DanK]

and your conclusion is?

[rpcrowe]

I don't really see a substantial difference in any of the four images when viewed in the size posted. Of course, there is a difference when I go into lightbox and enlarge the image.

So, my conclusion is that in posting images to this site, I might as well go with the smaller size images, both from uploading to smugmug and in selecting a size for posting to CiC.

Am I correct, or are my old eyes fooling me?

[Rufus]

I am not sure there is perceptible difference even in Lightbox when the images are displayed at the same physical size on the screen. But the images with the larger number of pixels in the dimensions are displayed as larger images when expanded to actual size using the icon to the left of Lightbox's X-Close icon.

Which leads to me a question that I have wondered about for some time, namely why is that for some images posted to CiC the site shows the "expand to actual size" icon as active and others show it greyed out and inoperative?

[Manfred M]

Richard - I see no difference when looking at the four images displayed on the site. However, when Lightbox is used and the larger images are displayed, there is definitely a significant difference.

I find that the standard display size at CiC is reasonably effective for identifying issues that are easy to identify, but if one is looking at finer details, then the Lightbox view in very useful.

I think the answer is to pick a reasonably large image (around 2K pixels on the longest side) when posting. That way we get a good overall view of the image but still have an ablity to drill down into the work. The size I suggested also supports reasonably fast image load times; something that matters to people with slower internet connections.

[Shadowman]

I see the same differences as you do.

[pschlute]

Which leads to me a question that I have wondered about for some time, namely why is that for some images posted to CiC the site shows the "expand to actual size" icon as active and others show it greyed out and inoperative?

If the image that is linked to/uploaded has a size that is the same or smaller than the normal lightbox view size then it is already being displayed at "actual" size.

[Rufus]

If the image that is linked to/uploaded has a size that is the same or smaller than the normal lightbox view size then it is already being displayed at "actual" size.

That makes sense and is what I suspected but I wasn't sure how to tell if it is displaying at "actual" size. Thanks for clarifying.