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I've noticed that only within the last 2 or 3 days when uploading photos to the Auctiva site the original files sizes of larger images (800x600 up to the 1024x768 maximum allowed) are now being sharply reduced below the level necessary for sharp resolution at those larger sizes. 800x600 pics need a file size of around 100KB to look sharp. The upload process is now compressing the file sizes to less than half that, resulting in noticeably "fuzzy" pics when viewed full size (100%). The only solution seems to be to upload smaller sizes of about 640x480 so the loss of sharpness is not noticable, but then we supersize to smaller, much less impressive images with much less detail. The ability to display large sharp supersized photos of high resolution is very important; they are a powerful selling tool and give us a competitive edge in our listings. This file reduction seems to be happening regardless of which downloader is used, and is a very recent development, a temporary one I hope. Anyone else notice this?
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If you are using any kind of internet accelerator to speed up your web surfing one of the things they do to make things faster is crunch images to a much lower quality so that they download faster.

Some ISP's do that for you automatically such as AOL. If you use AOL there is a setting you can change to turn that feature off.

Only people with those programs running would see fuzzier images. If you post the URL to one of your full size 1024x768 images here we can tell you if it looks fuzzy to us and how many bytes the image is and you can compare that to what you are seeing.
Thanks for the ideas. However, after a few tests I've discovered: if I attempt to upload an image larger than the maximum allowable 1024x768, Auctiva will predictably downsize it to that size (common knowledge), but the FINAL file size will be much smaller than if I reduce the image size to 1024x768 BEFORE uploading. If I do that then the file size will not be reduced at all when uploading, resulting in a larger FINAL file size, and a noticeably higher quality photo. Moral: For best results: size your pic to 1024x768 or smaller (768x768 for square pics) before uploading, then the software will leave it alone.
From what I can guess the green background of the felt you take your pictures with uses a lot of colors and shades. That probably results in an image that doesn't compress as well while still leaving a good quality image with the compression levels we use.

One thing you could try would be using a more solid color material. Perhaps a white sheet. If you did that and the background color was more of a solid it would compress perfectly leaving a almost all the rest of the space of the image for the item. So you'd end up with a sharp image, and still have it be a small # of bytes so that it downloads fast for buyers viewing your items.

That's the goal you want to shoot for. Great looking images that are sharp, but are still as small as they can be # of bytes. Since they only need to download it if they click the supersize link though it's probably ok for the image there to be a little bit bigger.
Jeff,

I tested your idea of using a plainer backround, and you are correct. A plain white backround resulted in a whopping 40% smaller file size (starting at the JPG compression stage within my camera) than the textured green backround I have been using, yet retaining about the SAME level of picture quality in the subject area when viewed onscreen.

You indicated that this is possible because, compared to the "green" picture, relatively more compression was taking place in the plain white backround area, leaving the subject area less compressed. Makes sense. This 40% file size advantage, and equal quality, held throughout my further downsizing, allowing for smaller file sizes to upload. (It also allows for a little more latitude to use a little larger file size anytime you want better quality, or a larger picture). One more trick...good to know.

Thanks for helping to clarify an often confusing subject. Yes, Auctiva is a gem--great work! Smile
Wow, 40%. That's pretty good. If you still want to use green I think that would work too but maybe a more solid material. Like maybe some green silk, although that may have some shine to it which may tend to cause some gradients in the green. Black may work as well.

I actually found the green you used to be unique in that most sellers use black or white. So if you think that helps you might be able to find a fabric that gives a more solid green and you can keep that 40% size reduction and still keep the color that works for you.

I think it has to do more with the green being felt or wool or something so there seemed to be a lot of shades of green. When the software that crunchs images is shrinking them it looks at pixels next to eachother. Whenever it finds a few in a row that are exactly the same or close enough that the human eye can't tell the difference it combines them all into 1. Thus maybe 5-10 pixels get converted to 1 giving a 50-90% space crunch. That's the simple explanation anyways. There are many different algorithms for image shrinking and I'm no expert by far. I just know that when there are a lof similar colors near eachother the image can be shrunk down a lot.
The impressive 40% reduction in file size is probably atypical. For comparison purposes I wanted to emphasize any differences between the two backrounds, so I had more backround showing than I normally would. I would normally crop this extra backround out of the pic, which would result in a less dramatic difference.

I believe the effect is still significant enough to consider when trying to achieve an optimum balance between smaller file size vs. acceptable picture quality. Of course other considerations often can't be ignored; for example, some subjects photograph much better with certain backrounds. In the end, it's the most EFFECTIVE photos we are after. The more techniques we can use to achieve that the better.

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