Blogging with photos

[angtomczak]

I have a blog where I mostly post photo's. I want to make sure I'm doing what should be done for optimum performance. I use Picassa to store the photos and link to the blog post.

What is an appropriate File Size and/or Dimension for web viewing?

Also, when I Save As JPEG from Photoshop Elements, which Image Options and Format Options should I choose?

What is the best way to reduce the size of my file? (I start with a raw file and am saving to jpeg after editing.)

Thanks.

[freybear3]

The Average Web Page - Preliminary Results

this site should be what your looking for, hope it helps

[wulf]

What is the date of that research? Near the top of the page it references research from 2006 and there is a reference at the bottom from 2008. In internet terms, that is a bit like "paleolithic" and "bronze age"!

My observation, working in the field of web development, is that the average desktop user has a large screen and pretty fast connection. However, in the last year or so there have been an increasing number of people accessing the web via devices like iPhones and netbooks. In other words, back to very small screens and slower connections, sometimes even involving a cost to the user if too much data is downloaded!

One of the reasons I started using Flickr as an online host for all my photos was because it provided the service of presenting versions of my photos at a number of different sizes. Their medium size - 500px on the longest side - is large enough to get a decent view of a photo even though it sometimes looks a bit small next to shots that are 800px wide on DPS.

For most cases, presenting a smaller preview image and giving the option of viewing it larger is a smart way to go. Casual visitors aren't hit with a slow-loading page and even those for whom screen size and connection speed are no issues can get an overview and decide what they want to view at full resolution.

Wulf

[angtomczak]

I just did a little test blog, and Flickr works much better!!! Thanks!

[angtomczak]

One more question.... What size should I be uploading? When I finish editing and save in JPEG, if I save at Maximum quality, then my photo's are 8 MB or more. I don't think I need to upload files that large, do I?

What pixel dimensions and resolution is adequate?

[wulf]

Size is up to you. Since Flickr gives me a range of options, I upload them full size - 3008x2000 is the max from my D40 although that is, of course, only a 6MP camera.

As for quality, it would be worth doing some research into what level of JPEG compression starts to noticeably degrade the picture. I've got a vague notion that attempts to save a JPEG image at 100% quality actually boosts the size of the file while moving down to the 85-95% range makes no visible difference (to casual inspection) while reducing the file size a lot. If you keep resaving a JPEG image, you lose quality each time but once or twice won't make a lot of difference.

Therefore, unless your images are very large, you should be able to get them weighing less than 8MB, which will make uploading them much faster.

Wulf

[dcclark]

I highly agree about flickr.

I typically upload photos to flickr at 95% jpeg quality, and they're usually in the 2.5 - 3 MB range. I have never been able to see ANY jpeg compression artifacts at this quality. I would suppose that going all the way down to 85% shouldn't show anything either, if you're worried. But then flickr gives you scaled versions, which takes care of the file size problem anyhow -- so it hardly matters if you upload a very large one, as long as you link to the smaller ones.

[wulf]

I've just done a quick experiment. I took a 500x500px crop from the centre of this photo (at Flickr large size - less quality than the original but looking pretty good to the naked eye), copied it several times (a non-destructive change) and then saved at varying levels of JPEG compression using The Gimp.

File sizes first:

100% quality - 168KB
90% quality - 51KB
80% quality - 33KB
70% quality - 26KB
60% quality - 22KB
30% quality - 13KB

By the time you get down to 30% you can see the compression artifacts but even there, not as much as I thought. Certainly 90% or even 80% looks acceptable even when zoomed in. It wouldn't be the quality of image you would want to print from but few people put images on the web so that other people can print them at wonderful quality!

Wulf

[angtomczak]

First, THANKS!

Second, what's the better way to go: Crop or Resize?

[dcclark]

Crop if you want to change the composition and content of the photo.

Resize if you want to literally make the image take up less space (fewer pixels, but containing the same actual image).

Cropping and Resizing are very different things, they're not really something you choose between.