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Desmond Chan
07-26-2010, 08:17 PM
Hi all,

Yesterday I noticed that the file that I uploaded to BPN was reduced in size after the upload. The file I uploaded is 201Kb, but the file size shown in the "Manage Attachments " window says it's only 50+ Kb. I did an experiment today and uploaded a 521Kb file. After the upload, the file size in the "Manage Attachments" window says it's 112K, which is below 200Kb and so is "legal" and accepted for posting.

According to the guideline, the largest file size allowed for upload is 200Kb. It seems to me, based on what I've found now, it's not about the original file size of the image that I want to upload but what size it is after the upload. Is that right?

In case you're asking if it has to do with how I prepare the image file, I'd say not since if it's 200Kb in size then it's 200Kb in size no matter what you did to make that file that size.

So, what happens during the upload? Is that supposed to happen?


Desmond

John Chardine
07-26-2010, 08:24 PM
Not exactly Desmond (incidentally I have seen this behaviour before).

First, I find that sometimes jpegs out of Photoshop overshoot their predicted size. They do this all the time if you just Save as, and rarely but sometimes in Save for Web and Devices. If you overshoot the BPN limit, say to 201kb, there is an automatic and rather aggressive downsizer that kicks in and really compresses and degrades the image. To prevent this I shoot for about 195kb in Save for Web and Devices and I never overshoot.

Desmond Chan
07-26-2010, 08:36 PM
They do this all the time if you just Save as, and rarely but sometimes in Save for Web and Devices. [quote]

I have not used "Save as" for a long time now. I use "Save for Web and Devices" these days and always save it below 200Kb because of the file size guideline. Perhaps I got a tiny over-shoot yesterday :D

[quote] If you overshoot the BPN limit, say to 201kb, there is an automatic and rather aggressive downsizer that kicks in and really compresses and degrades the image. To prevent this I shoot for about 195kb in Save for Web and Devices and I never overshoot.

Aggressive it certainly seems to be. I did another experiment and uploaded a 86K file and the reduction does not seem to happen. Anyway, it does seem like we can upload file of actual file size bigger than 200Kb, even bigger than 500Kb and let BPN down-size it to 200 or lower :p How's that affect the final image quality I think I have to try it out to see.

Thanks John !


Desmond

Chris Ober
07-28-2010, 08:53 AM
The size limit is based upon the file size once saved to your local drive and not what Photoshop reports.
How does it affect it? That will depend on the size it's resizing from and the amount of detail in the image. Usually it's quite adverse.

Please don't make a habit of uploading larger size images and making the server/software resize it for you. The auto-resize is in place for those occasions somebody might decide to upload a huge resolution file, ignoring the guidelines or not checking them at all. It also keeps storage requirements down.

Axel Hildebrandt
07-28-2010, 08:58 AM
Desmond, as John I try to keep files smaller than 195 kB when I want to upload them to the BPN server. If they are downsized because of the file size they also lose sharpness.

Desmond Chan
07-29-2010, 12:59 AM
I found out the auto-file-shrink thing totally by accident. Except that time, I always keep the file size smaller than the maximum allowed. I was surprised that there was no error message telling me that the file was too large. Personally, I think giving out an error message and not allowing the file to be uploaded should be a better way to do it as far as controlling the file size is concerned. Now you are allowing "accidents" to happen :p

Ken Childs
08-01-2010, 10:02 AM
I found out the auto-file-shrink thing totally by accident. Except that time, I always keep the file size smaller than the maximum allowed. I was surprised that there was no error message telling me that the file was too large. Personally, I think giving out an error message and not allowing the file to be uploaded should be a better way to do it as far as controlling the file size is concerned. Now you are allowing "accidents" to happen :p
I have to agree with Desmond. In the long run, having these inferior quality images uploaded will probably end up using more server space because once the low quality image is noticed, the poster will most likely upload a corrected version.

Roman Kurywczak
08-01-2010, 10:24 AM
Another vote for just not allowing it! I liked it when it told me the file size exceed the limit.......can't upload.....we need to have that back I think!

William Malacarne
08-01-2010, 10:39 AM
I agree with putting it back the old way.....I very much would also like for people to not strip the EXIF data ftom the photos. One can learn so much more from it IMHO. If i am am not mistaken it requirs only something like 2K for it.

Bill

Grace Scalzo
08-01-2010, 11:00 AM
I give up. I'm trying to upload an image that is 120kb and bpn is uploading it as 30.4 kb. Sheesh. Frustrating.

William Malacarne
08-01-2010, 11:02 AM
I give up. I'm trying to upload an image that is 120kb and bpn is uploading it as 30.4 kb. Sheesh. Frustrating.

How many pixels across the bottom and on the side?

Bill

Roman Kurywczak
08-01-2010, 11:05 AM
Notified the "upper management":D......should get a response soon! Make sure you are not over 1024 on horizontal or 800 on the vert........seems to have same issue.

Grace Scalzo
08-01-2010, 11:05 AM
Ht- 864 w - 640

Grace Scalzo
08-01-2010, 11:06 AM
Thanks, guys. I guess that my ht of 864 was the problem.