JPEG made smaller, colour goes to pot

  Morpheus© 09:20 29 May 2003

hi.i will try and put this like it is, i have taken some pics with a digital camera, the size they come out from the camera onto the PC screen are, and this is set by the camera, is 2240x1488,

so i put them into micrografx picture publisher, and reduce them down, with the sizing tool, the problem is that the images have marks on them, i guess from making them smaller, clear as a bell when full size.if i may be as bold, if you go here,

click here

and click on page 4, then look at the two bottom pics, and the faces, you will see what i mean. what am i doing wrong? thanks for any help.

  Gongoozler 09:38 29 May 2003

Hi Morpheus©. The pictures look like they have been reduced to a much lower number of colours or grey levels, so what should have been a gradual colour change becomes clearly stepped. Are you reducing the file size by increasing the jpeg compression factor? This always degrades the picture quality. If you are resampling to a smaller number of pixels you should retain the quality but with a smaller picture. I have never used Picture Publisher. My camera came with Pixela ImageMixer which I find useless. I use Corel PhotoPaint 7 (1995 version) and find that as long as I don't push the jpeg compression too far I get excellent results, and even IrfanView gives good results in resampling to a smaller image size. If you like, I'll e-mail you a picture that I have reduced in size.

  Morpheus© 09:44 29 May 2003

HI, even through i reduce them down, they are reduced even more by the web site.., if i may can i send you pic before i have messed with it. and ,yes, i would like to see a pic you have got at.....

  hssutton 09:59 29 May 2003

Looking at your photo's I see the max size is approx 12k 400x266 pixels. this is the problem. if this is the maximum size image allowed on this site go find another. The minimum size I would upload my images would be 50k @ approx 500x400 pixels. have a look click here And at the same time join us, you will be made very welcome.


  Morpheus© 10:17 29 May 2003

hi, the deed is done, thanks....but i think i should have made them smaller to start with, the site took them straight off the floppy disk..

  hssutton 10:46 29 May 2003

Hi Morpheus

From what you have just stated, methinks the problem started at your end. You say "the site took them straight off your floppy disk". Just how many did you have on the disk to start with. I couldn't fit one photo onto a floppy. Or did you mean Hardrive?.

  Morpheus© 11:01 29 May 2003

hi, there are two images on the floppy disk, just had a look and at the bottom of the image it has, on each one 403.5kb/9.54mb,and 1488x2240 BPP, whatever BPP is.. i am getting lost here :-(

  Morpheus© 11:03 29 May 2003

just to correct the above it has.

1488x2240x24 BPP

  Gongoozler 11:47 29 May 2003

Hi Morpheus©. BPP Is Bits Per Pixel. This is equivalent to 16.7 milliion colours. The picture you sent me looks good quality but has quite high jpeg compression. Corel PhotoPaint gives the jpeg compression factor as 150, where 2 is best quality and 255 is worst. I find 100 is good for average, and about 25 for good quality. The picture is reported as 1488 pixels wide by 2240 pixels high. It may be worth experimenting with fewer pixels and less aggressive jpeg compression if you want to reduce the file size without losing quality.

  Morpheus© 11:55 29 May 2003

thanks, i do have adobe photoshop, but too hard to understand...i will go back and try again..thanks for all the help, i will tick the box for now, and come back later, if i get stuck.. thanks again.

  anchor 12:31 29 May 2003

Just had a look at the pics, and would like to make the following comments:

The problem appears to me that firstly, you have saved them as gifs, which only allow 256 colours, and tend to be significantly larger than jpgs. Therefore, in order to reduce the file size to something reasonable, (about 270kb), you have had to compress them a lot.

Getting good image quality on the web is a balance between picture size and compression. I do recommend that you always use jpg`s for your web pictures.

I use the Paint Shop Pro 7 jpg optimiser, which allows you to see the results with various levels of compression. The problem I see in the girls faces is typical of too much compression. If I can help further, please contact me.

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