I realize that the vertical dimension can not be as large as the horizontal dimension.... But, why is it that the vertical dimension viewed on a vertically oriented image is less than the vertical dimension shown on a horizontally oriented image.  I would think, either way, that the vertical dimension would be the same.

Peter F. 

The reason horizontal images always show larger on a screen is because monitors are wider than they are taller. There is simply not enough pixels to display a vertical image larger without introducing a scrollbar which is a big no-no in maintaining good viewer experience.

On your specific resolution, and given that you have a bookmarks bar enabled in your browser window which takes away vertical space, you have a suboptimal experience. But you can still click the image to see larger details in the Dim-the-Lights view.

Your viewers will all have different screen resolutions so even if you optimized it somewhat for your specific screen, it will not look good for others, which is what we are all concerned about.

Take a look at your site on different screen resolutions and you will see that the experience is very good, at least this is what our customers are telling us.

Peter, part of the reason that you will find a vertical, or portrait oriented image may be smaller along the vertical access as a horizontal, or landscape oriented image, is because the Zenfolio 'system' creates display images at certain resolution sizes, then chooses the most optimal display size to display in the given screen real-estate.  It does not create an image on the fly sized to whatever screen real-estate is available.

The reason for pre-choosing set display sizes is for greater speed in displaying images.  The images have already been created rather than the viewer waiting on a display image to be created for 'exactly' their particular available screen viewing area.

For that reason, you can see a smaller image in what looks like you should have more room for image, and as you slowly increase the screen real-estate, suddenly you will get the next size larger image that will fill the area.

Hope that helps and doesn't confuse!

 Thanks, Kevin.  I was beginning to get the idea but your reply has helped.  I have noticed that in spite of the mis-matched sizes, when I hit the F11 button to maximize the screen, the vertical shots "catch up" with the vertical dimension of the horizontal images.

Thanks.

Peter

yes.  every little think works together in a browser to 'eat up' screen realestate.  Part of the game of web design, is trying to minimize those effects.