Please see the exchange between me and Kristina on this photo of mine to understand what I mean about thsi loss of quality on uploading, that I've only just become aware of:

http://andrewgould.aminus3.com/image/2007-10-26.html

I'll write to Jason on aminus3 support about the issue. I feel that there should be a requirement to limit uploads to a width of 800 pixels, or at least it should be made clear that there can be a quality loss if the image is wider.

Don't know if there's a limit for height because I'm not exceeding it with my uploads in portrait orientation, but will ask about this, too.

I'll report back here when I have an answer.

Interesting exchange between you and Kristina! You said your jpeg was much sharper before uploading. One question I have is how did you save your jpeg before uploading! Did you Save for Web (older version of PS such as PS7) I believe newer versions of Photoshop have a Bicubic Smoother in the resizing dialogue. Saving as Bicubic like you would for printing, will wreck an image for the web. But, you probably know this anyway!

Another suggestion is for you to upload your photo here using the Add Image to Post at the bottom of the text area in these messages. It will only show a large thumbnail on these posts but when you click on the thumbnail it will show up as a large photo on Image Poster. Then we can see if it is an am3 problem if it is sharper on here.

I'm interested to know what response you get from Jason!

_________________
You don't take a picture - you make a picture - Ansel Adams
http://annesgallery.aminus3.com

Andrew
I have noticed the problem before and decided not to upload pictures bigger that 800px in width. I believe that the AM3 application resize method cannot be as good as Photoshop or any pro application for image processing.
Like Anne, I'll be glad to see the big version attached here to check the difference too.

_________________
It's life that is important not just living, it's the happiness that matters not just smiling.
http://bsurprised.aminus3.com/

There has been some confusion over our image upload processes which the FAQ does not currently cover so I'll explain it here (and maybe one day update the FAQ too)

Andrew's observations are correct... images greater than 800 pixels are resized to 800 pixels for the large image. We do not have a limit on the height of images although I've never personally tried anything much bigger than 2000 pixels.

Probably the worst thing to do is upload an image that is very close to 800 pixels like 802 as the image gets very distorted based on the small pixel adjustment.

In addition to resizing, we apply some compression which is why people have observed a 500k image becomes < 100k after upload.

The reason for resizing and compressing is because we are paying for disk space which can add up quickly as our membership grows. As many of you are aware, we are in the process of creating a pay premium package in order to offset our costs.

We recognize that image quality is a top priority for many members and (as of now) the premium package will offer better image quality and the option to display sizes larger than 800 pixels. Unfortunately I can't provide a date when this will be available at the moment. Free members will still get the same quality images available today which is we feel is quite acceptable in most cases.

_________________
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Jason Kravitz
Aminus3 co-creator, admin
and community relations guy
http://jason.aminus3.com

Firstly, thanks to Anne and bsurprised for the suggestions and offers of help.

I do my resizing with Photoshop CS3 (same as CS2) Image Processor. After sharpening and resizing, I chose either jpeg compression 11 or 12 (the latter being the highest). These jpegs look just as sharp on my 15.4"supersharp laptop before upload as the original 8 megapixel TIFFs.

Furthermore, we now have Jason's confirmation that uploading larger than 800 pixels in width will cause a loss in image quality, so I don't think I need to upload any photos here for checking.

If anyone wishes to confirm that this is a real problem, just try uploading a larger than 800 mp wide file, right click and copy it to your desktop, delete it from aminus3, then compare it to the preuploaded version on your pc. You're sure to see the difference immediately (as long as this photo prepared for upload was suitably sharp, of course). It will certainly be very clear in photos that have lines and edges or signs in them.

I do hope that you'll be able to add something about this to the FAQ sooner rather than later, Jason, so that others won't upload for months before realising that they could have posted images that are considerably sharper.

I decided to come back here and add what is below after commenting on the latest photo by Manuela -(10th Jan 2008) -- http://manuela.aminus3.com/ -- where she mentions the problem of reduced quality when uploading landscape format photos wider than 800 pixels.

This reminded me that I had only recently realised that it's not just the width that's important when uploading. If you check the properties on any photo on aminus3, you'll see that it will be barely over 100kbs. The solution is to be sure that your photos are no larger than about 100kbs so that they will not be further reduced in the upload process. It seems to me from my tests in uploading that this reducing of file sizes by aminus3 also leads to inferior quality on the screen.

I feel very strongly that there should be guidelines regarding this in the aminus3 FAQ. It would be even better if they had some mechanism in place to actually prevent photos from being uploaded at sizes and/or weights that are unsuitable.

Hi Andrew and those watching this thread. My apologies - a new FAQ entry was long over due. There is not too much science to the upload process but I hope it will clear some things up for everyone.

(note you can access this by clicking on the link in this post or from the support page on your individual blog)

_________________
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Jason Kravitz
Aminus3 co-creator, admin
and community relations guy
http://jason.aminus3.com

Thanks for the new FAQ, Jason.

I think it's very reasonable that you would want to compress large files due to the storage space that they take up, but don't understand why even an 80kb file would go through this process. It's obvious then that I was wrong to assume that uploading at 100kb or less would ensure no reduction in quality.

As the FAQ article mentions, compression is a percentage of all files regardless of size. We don't have any rule that says if a file is smaller than a given size, it will not be compressed.

Given our plan to support 100% uncompressed images for premium members, it seems unfair to have a loophole (like images under 100k are not compressed) as there is less value added for the people that choose to pay for this feature.

_________________
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Jason Kravitz
Aminus3 co-creator, admin
and community relations guy
http://jason.aminus3.com

Thanks for the reply, Jason, but I don't see why you'd consider that a "loophole". It just doesn't seem necessary to compress what is already very small, and future premium members would still have a huge advantage over those who could only upload at 100kb or so.

Having said that, I don't want you to think of this as a serious criticism as to the way aminus3 is run, as I really do appreciate what the site offers.

Andrew.

I'm back after thinking the situation over a little more...

The only thing that does worry me about this situation is that it seems to me that on uploading, it is impossible to know how much to reduce the file weight so as to have the best sharpness possible under the circumstances.

(note: Andrew and I have been talking via email as well so I'll paste my email reply to him which somewhat addresses these concerns)

As I've stated before, we believe that with the current upload process,
most images still look quite good. Comparing an image to an
uncompressed original will often result in noticeable differences.
However, I don't look at other member photos and think that they could
be better because I have not seen the original. There are many
excellent looking photos every day and all these photos (including my
own) are going through the same upload process.

I think for a lot of members, the settings are good enough for their
needs. For those that demand the best, we will offer a way for them to
showcase their work as it is meant to be seen, without any alteration.

_________________
~~~~~~~~~~~~~~~~~~~~~
Jason Kravitz
Aminus3 co-creator, admin
and community relations guy
http://jason.aminus3.com

Quote:

I do my resizing with Photoshop CS3 (same as CS2) Image Processor. After sharpening and resizing, I chose either jpeg compression 11 or 12 (the latter being the highest). These jpegs look just as sharp on my 15.4"supersharp laptop before upload as the original 8 megapixel TIFFs.

Just another note on the above subject Andrew! I have quoted a piece of your post that I noticed earlier. This is because you mention setting the compression at the highest level before saving. But, if you are working with the resampling set at Bicubic in the dialogue, then your photos will be just as sharp as your tiff files, but for print only.

For web use, when you have the resampling set to Bicubic, the interpolation changes the color pixels to compensate for the different size resulting in a photo that will not look sharp on the web on any site. Before I knew this, even photos posted on my personal web site - where there was no compression put on them - they didn't look so good as the originals. In earlier versions of Photoshop like my own version 7, I have to go to the File menu and Save For Web, where the next window sorts out the photo to bicubic smooth which makes it just as sharp or unsharp as the case may be, as it was in the larger file version on my computer. I believe I read in a Photoshop Tutorial which was actually meant for Photoshop CS2 and CS3 users, that instead of having to go to the File menu to Save For Web, that CS2 and CS3 have the option in the resizing window to change the Bicubic to "Bicubic Smoother".

So I am wondering if you have not been doing this, but saving as you would for printing.

_________________
You don't take a picture - you make a picture - Ansel Adams
http://annesgallery.aminus3.com

Sorry for the delay in responding, Anne.

When you use the Image Processor in Photoshop CS2 or CS3, there's nothing to choose from in resampling as far as I can see. I've never used the Save for Web option, as I've read that it removes the EXIF information.

I will, however, look into this resampling business, so thanks for the advice.

You will only lose the EXIF info when Saving For Web if you set too much JPEG compression. There is an option there (in mine it seems to be the default) at High 60%.

In ordinary saving, the resampling fills in the spaces created when you change the resolution down to 72 dpi from say 300 dpi. the pixels it creates are full of color like red etc. which stops the image looking too "thin" as a print. But really looks terrible if viewed on the web! Results in a loss of sharpness look, even though it still looks OK before you upload it. If you view the pics with a magnifier in your Browser tools you can see all these pixels filled in with color.

Anyway, good luck with that - it is in the Adobe Tutorials somewhere if you go into Help and look for it!

I am going to post on the new Forum from now on. Aminus3 Forum

_________________
You don't take a picture - you make a picture - Ansel Adams
http://annesgallery.aminus3.com

Thanks for the reply, Anne. See you on the new forum...