Reducing size of jpg/jpeg

11th July 2007, 07:06
Hello All;
I wonder if I might ask a question regarding the Disc Size for jpeg/jpg.
The size here measured in KB, but mostly MB in my case

I often receive scans sent me roughly 3300x2100 pixels, and scanned at 600dpi. The size on disc is around 290-300KM.

However, when I scan photographs, same Postcard size, @ 600 dpi greyscale with unmask sharp ON. My size is as follows.
Roughly 3300x2100 same as those received, but the disc size for mine is around 2MB for grayscale, and more than double that for color. I notice too every once in awhile one of my big scans will change, and the filesize will have dropped to around 300-500kb.

Is there something I am doing wrong? Any help or direction here will be appreciated, and I thank you in advance.

K urgess
11th July 2007, 10:40
It all depends on the compression used when saving. It also depends on the ammount of detail in the picture. So the size will only be identical for the same picture if scanned at the same rate and saved with the same compression. Even then that's not guaranteed.
The more compression used the more detail is lost as the software averages pixels and juggles colours.
It all depends on what size you want to view or print at.
Best thing to do is experiment until you get it right. Good thing about electronic/digital pictures is you can always start again if you c*ck up.
Check what your scanning software can do and that the settings are consistent. If you scan to save and then scan to email your software can change all the parameters to make the picture size right for emailing.
Hope this helps

Pat Thompson
11th July 2007, 11:00

For your information Uncle Bill, aka Microsoft, have a free utility called Photo Resizer available from the Microsoft web site in the power tools section. I allows you to scan pretty much to whatever size you want but to reduce the picture down to various sizes for e-mailing and for use on the web. Naturally as Marconi Sahib states there is a quid-pro-quo in the picture quality department. But is is free and you can play with it to see if it soes it for you.


Pat Thompson

PS Uncle Bill giving things way for free...whatever next.


11th July 2007, 11:10
Change your scans to 300 dpi and under. You don't need that kind of quality for uploading. There should be a settings on the scanner software to let you adjust that.

Pat McCardle
11th July 2007, 11:44
Use PICASA 2 it's free & easy to use when resizing, editing etc. Free download from GOOGLE

12th July 2007, 07:06
Thank you all for your help here it is most appreciated, and I will try and do everything you have told me about. I have to tell you though these PCs I own seem to have a mind of their own.

Earlier tonight I sent an email with attachment jpg of 1.7 meg to my other email address on my laptop from my desktop by way of Ma Bell not through a network. It arrived and opened the same size 1.7m. I then deceided to send this same ship image [1.7m] to a good friend. In the email attachment window it showed it as 670kb. Now that is hard for me to understand. After sending it I went to the Sent folder, and there it was at 670kb.

I often scan my pix as tiff files or as photoshop files, and eventually put them on a DVD. I don't mind the size here as I want [hope] to keep them for the future. I also edit them, removing spots and what have you, and that even makes them bigger. Again that is not my problem. To work with them for reference I have been known to reduce the actual size down to 1280 wide to fit my monitor screen. This, of course, also reduces the file size which is great. I just haven't figured out yet a standard approach to keep the picture size big while reducing the filesize to acceptable levels.

I think you gentlemen have hit the nail on the head with your advice, and in the coming days I will experiment with all your ideas.

Thank you all ever so much.