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800 pxl long dimension images

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prinothcat
 
Posts: 662

800 pxl long dimension images

Post Sat May 02, 2009 4:28 pm


Have any of you out there who use the 800 pxl largest dimension theory for Pbase uploads noticed that recently the upload sequence is now recompressing your original image... sometimes? It seems to be happening to me but I can;t tell why. It doesn't always recompress but when it does it makes the image look bad. Now do you suppose we need to upload an 800 pxl image and a full size to see which looks worse as the default original size?

dougj
 
Posts: 2276

Re: 800 pxl long dimension images

Post Sat May 02, 2009 6:10 pm


Chris, I keep mine under 800px and haven't noticed compression, although the quantity I've uploaded lately has been small.

prinothcat
 
Posts: 662

Re: 800 pxl long dimension images

Post Sat May 02, 2009 10:03 pm


Doug, I've been right on 800 pxl for my long dimension for a while now and have not had them recompressed until just last week. My latest have all recompressed. I guess I'll try 799 pxl .... :roll:

alangrant
 
Posts: 861

Re: 800 pxl long dimension images

Post Sun May 03, 2009 9:39 am


So what actually happens, do you end up with "large" and "original" both the same size? Or is the original being replaced by the recompressed version?

It's never happened me but I haven't uploaded anything for quite a while.
Alan
Travel Photos - http://www.pbase.com/alangrant
Balkanology: Explore Southeast Europe - http://www.balkanology.com/

dougj
 
Posts: 2276

Re: 800 pxl long dimension images

Post Sun May 03, 2009 10:17 am


Chris, I just tried one @ 799px and a Large size was not generated.

Yes Alan, 800px seems to be, or was, the threshold for generating a Large size option for viewing.

I wish we had the option to provide the available sizes, for now I have a note suggesting viewers select Original size.

prinothcat
 
Posts: 662

Re: 800 pxl long dimension images

Post Sun May 03, 2009 4:03 pm


I'm headed out to shoot some this afternoon and will play around some more to see what happens.

akmc_in_au
 
Posts: 921

Re: 800 pxl long dimension images

Post Mon May 04, 2009 3:58 am


prinothcat wrote:Have any of you out there who use the 800 pxl largest dimension theory for Pbase uploads noticed that recently the upload sequence is now recompressing your original image... sometimes? It seems to be happening to me but I can;t tell why. It doesn't always recompress but when it does it makes the image look bad. Now do you suppose we need to upload an 800 pxl image and a full size to see which looks worse as the default original size?


I uploaded about 50 images over the weekend; some were exactly 800 pixels on the longest size. (Typically portrait orientation shots, most of my landscape orientations were 1000 to 1200 though I think that there were a couple of 800's in there as well from memory.)

I didn't notice any compression happening on the Originals. I don't know whether this makes any difference, but most of mine were uploaded one at a time except for the first bunch where I used the advanced upload dialog to load about 5. (That took so long that I didn't try it a second time, aside from which it takes me a while to write up the captions anyway, so the single load option works fine for me.)

If you're using a zip upload, it might be an idea to try the single image upload option and see whether that makes a difference.

waggonerphotos
 
Posts: 176

Re: 800 pxl long dimension images

Post Mon May 04, 2009 11:30 pm


Chris, the problem I've been having, and I thought it might just be me, is that my images 800px on the long side after being uploaded to Pbase are loosing sharpness. I end up with images sized small, medium and original however the image quality has been degraded. The file size does not appear to have changed from what I uploaded which would be indicative of a change in compression quality. In short I don't understand whats happening. I've tried over sharpening my downsized image prior to upload but that is a guessing game with it's own problems. If this is similar to what you are experiencing and if you've found any solutions I would appreciate hearing from you?
Bob Waggoner
Photographs comprise the communal memory of our times. (Unknown)

dougj
 
Posts: 2276

Re: 800 pxl long dimension images

Post Mon May 04, 2009 11:57 pm


Bob, try downloading the original size photo, then compare this one to the one you uploaded. I haven't done this in awhile, but when I checked this awhile ago by subtracted the 2 Photoshop I determined there was no difference. It will be interesting to see if anything has changed. I'd do it now but I'm on my out to the office.

alangrant
 
Posts: 861

Re: 800 pxl long dimension images

Post Tue May 05, 2009 8:53 pm


Bob, maybe you already know this but very often when people think they observe a degradation in image quality it turns out to be because they have saved it in something other than the RGB colour space. Given that the file size has not changed I'd say it's almost certain that PBase has not modified your image, so that the difference is likely to be something to do with the context in which you are viewing it (e.g. in a non-colour-managed browser versus in Photoshop).
Alan
Travel Photos - http://www.pbase.com/alangrant
Balkanology: Explore Southeast Europe - http://www.balkanology.com/

waggonerphotos
 
Posts: 176

Re: 800 pxl long dimension images

Post Sun May 10, 2009 8:06 pm


Hey guys, thankyou for the suggestions, i have tried or incorporated all. The bad news is that they didn't correct my problem! The good news is that I have identified the problem! FIREFOX!!!! I have been using Firefox for a long time so I didn't think the problem was with my browser but it is. For some reason a thought occurred to me, to see if the pictures looked the same in Explorer. They don't! In explorer the pictures I was concerned about appear sharp as a tack, not so in Firefox.
The only thing I can think of right at the moment is that certain settings may have been reset to default with an upgrade.
Now starts the fun of tinkering with the Firefox Browser.
Bob Waggoner
Photographs comprise the communal memory of our times. (Unknown)

dougj
 
Posts: 2276

Re: 800 pxl long dimension images

Post Mon May 11, 2009 12:37 am


That's interesting Bob, I'm not aware of any settings in FF that would cause this sharpness effect in photos. Have you tried opening the photos in the browsers directly from your hard drive and comparing them?

prinothcat
 
Posts: 662

Re: 800 pxl long dimension images

Post Mon May 11, 2009 12:52 am


waggonerphotos wrote:.
The only thing I can think of right at the moment is that certain settings may have been reset to default with an upgrade.
Now starts the fun of tinkering with the Firefox Browser.

Somewhere I saw a color profile manager for Firefox. Unfortunately I do not remember where, but I bet it was from the Mozilla plugins page. This might help. I've stopped using Firefox, since I switched to a Mac, but may go back at some point.

waggonerphotos
 
Posts: 176

Re: 800 pxl long dimension images

Post Mon May 11, 2009 6:42 am


Either the computer or I (BY Mistake) set the view zoom to minus 1. Smaller picture - less detail.
When i did a view zoom reset, the picture became slightly larger and was every bit as sharp as what I was seeing in Explorer. The difference in viewing size is hardly noticeable until you start examining an image for fine detail. I really don't remember changing the zoom level but who knows? Just goes to show though that the smallest detail can change the final outcome when working with a digital image. Thanks again for the suggestions - they were helpful and by the way, the color management module for Fire Fox is available as a plug in.
Bob Waggoner
Photographs comprise the communal memory of our times. (Unknown)

dougj
 
Posts: 2276

Re: 800 pxl long dimension images

Post Mon May 11, 2009 8:56 am


It's good you figured out what was causing the problem. Zoom is easy to enable and there's no indication that it's in use.


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