Fog, Trees, Ferns w/re-post

I just posted this image in ES&S and received a comment about the compression of the image. I've not had that problem in the past, but Richard mentioned compression in my previous post here. Is there something I need to check in my processing, I've not changed anything that I can remember. It's not really a big deal the full size images look fine, I'd just like to figure out what I'm doing to the jpegs

Thanks for any thoughts!

Sweet!

When you save the jpeg, just resize with a "bicubic sharper" to your web resolution, then "save as" jpeg and pick a jpeg compression level of 9-10. That will eliminate most jpeg compression artifacts.

Thomas,

Its showing up here as well.

It has nothing to do with your RAW or PS processing, its your web presentation. At this size and with as much detail in these images, there is too much jpeg compression occurring in order to get the image under 200KB. The method Matthew suggests will no doubt serve up a quality jpeg, but the file size might be too big. It varies image by image.

Your only other choice is to present these types of images in smaller sizes, 600 or 640 pixels instead of 720.

Richard is correct, if your image host has a size limit (like NPN's hosting service does) then you are basically stuck either with tons of compression artifacts or else making the image dimensions smaller.

Here's a re-sized version does it look any better?

I think both look great, especially the foggy background that's clear enough to show some of the trees in the mist.

Thomas, here are a couple of thoughts on JPEG compression. First, I think some people confuse loss of detail due to resolution with JPEG compression. However, in your first shot JPEG artifacts are very evident. The second point is that depending on your monitor resolution, it may be difficult to notice artifacts. I have my screen resolution really cranked up high on my desktop making for a smaller overall image on my screen, but at lower laptop resolutions the artifacts are much more noticeable. Thirdly, make sure you maximize the file size for detailed images to limit the artifacts. In your first shot, the file size is only 74k vs. the 200k NPN limit. And as Richard pointed out, if you need to convey detail, a smaller image will allow you to overcome some JPEG issues balanced against loss of detail due to resolution. In your first shot you can really see the artifacts if you zoom into the image and look for the "noise" in the fog between the hemlock branches. There are large areas of artifacts all along the right side and also in the ferns along the bottom. The second shot is much better especially in the fern and in the rightmost hemlock. In the upper center hemlock there are still some artifacts visible in the fog, but there is not much you can do since you have maximized the file size (195k).

To add to Matthew's suggestion, instead of using "Save As" JPEG, I use "Save for Web" which also creates a JPEG but allows greater control over the amount of compression showing the resulting file size and also includes a preview window where you can check for artifacts. Hope this helps.

John

It's a great image and information as well.

Thanks all for the info, I'll print all this out for future reference!! Thanks again!