A Photography forum. PhotoBanter.com

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » PhotoBanter.com forum » Digital Photography » Digital Photography
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Image re-sizing



 
 
Thread Tools Display Modes
  #1  
Old April 1st 05, 02:02 PM
Eos
external usenet poster
 
Posts: n/a
Default Image re-sizing

Sorry for what might be an obvious question to most but I would
appreciate a little advice on re-sizing an image.
I currently have an image which is appreox 3.4 mb which I have been
asked to send via e-mail at 100k.
Using photoshop I go to Image size and adjust the pixel dimension to
340 x 252 and save the JPEG at highest quality (12) and 72 pixels/inch.
However although the image is very good when I send the image it
appears quite small. Saving the image at a lesser image quality for a
smaller file increases the size dispalyed but the image is noticeably
poorer when dispalyed.
I am a little confused however in that I have an e-mail which has been
sent to me which has various pictures attached.
These are reasonable quality (on monitor),display a larger image when
opened, yet are only 30-40k in size !
I would appreciate therefore any (easy) advice as to the best method to
produce a 100k image which is going to give the best quality but yet be
dispalyed at a reasonable size when sent.
( I understand quality v size is probably a trade off ) but your help
is appreciated as to date I havn't really had to bother in reducing
files for this purpose.

Rob.

  #2  
Old April 1st 05, 02:30 PM
Bas v.d. Wiel
external usenet poster
 
Posts: n/a
Default

On Fri, 01 Apr 2005 05:02:39 -0800, Eos wrote:

snip
I would appreciate therefore any (easy) advice as to the best method to
produce a 100k image which is going to give the best quality but yet be
dispalyed at a reasonable size when sent.
( I understand quality v size is probably a trade off ) but your help
is appreciated as to date I havn't really had to bother in reducing
files for this purpose.

Rob.


Size versus quality is an inevitable tradeoff. There is no easy way to
tell how much quality you have to sacrifice to get to a certain file size
since the complexity of the image plays a major role in the amount of
compression you can achieve while retaining acceptable visible quality. Of
course reduction in pixel size will always help while maintaining visible
quality so that's a good start. What's the minimum required pixel size for
your recipient? Once you have that, save the picture at that size and
start increasing compression (=reducing quality) until you get a file that
fits inside 100KB. My personal experience is that images don't suffer a
whole lot when using Photoshop's JPG compression setting 8 but still
compress quite well. Usually you can even go a few steps further down, but
editing the resulting JPG will be out of the question because of very
noticable compression artifacts. So do your editing on the orignal and
compress that.

Hope this helps

Bas
  #3  
Old April 1st 05, 02:30 PM
Bas v.d. Wiel
external usenet poster
 
Posts: n/a
Default

On Fri, 01 Apr 2005 05:02:39 -0800, Eos wrote:

snip
I would appreciate therefore any (easy) advice as to the best method to
produce a 100k image which is going to give the best quality but yet be
dispalyed at a reasonable size when sent.
( I understand quality v size is probably a trade off ) but your help
is appreciated as to date I havn't really had to bother in reducing
files for this purpose.

Rob.


Size versus quality is an inevitable tradeoff. There is no easy way to
tell how much quality you have to sacrifice to get to a certain file size
since the complexity of the image plays a major role in the amount of
compression you can achieve while retaining acceptable visible quality. Of
course reduction in pixel size will always help while maintaining visible
quality so that's a good start. What's the minimum required pixel size for
your recipient? Once you have that, save the picture at that size and
start increasing compression (=reducing quality) until you get a file that
fits inside 100KB. My personal experience is that images don't suffer a
whole lot when using Photoshop's JPG compression setting 8 but still
compress quite well. Usually you can even go a few steps further down, but
editing the resulting JPG will be out of the question because of very
noticable compression artifacts. So do your editing on the orignal and
compress that.

Hope this helps

Bas
  #4  
Old April 1st 05, 05:59 PM
Scott W
external usenet poster
 
Posts: n/a
Default

How well an photo will compress depends on the content of the image,
lots of sky or an photo with the background out of focus will compress
more then a photo that is sharp and has lots of detail, like grass,
sand, trees.

Normally 100K would be good for about an 640 x 480 image but might be
able to go up to something like 800 x 600, this depends on how much
detail is in the photo. The best thing to do is to try saving it at
different sizes and see how they look. Do "Save For Web" this
strips off the EXIF data which will save some room and it allows find
control on the quality used to save the photo.

Scott

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
how to put the border around a headshot? Millenium Photographing People 38 December 22nd 18 01:26 PM
(pixle per inch) ppi is only 72 HELP Ian Hurst (Troyka) Digital Photography 12 December 22nd 04 02:27 AM
I started a 35mm B&W darkroom forum me In The Darkroom 153 December 20th 04 05:37 AM
8Mp Digital The Theoretical 35mm Quality Equivelant Matt 35mm Photo Equipment 932 December 17th 04 10:48 PM
IMAGE MANAGEMENT AND CREATIVITY HAS NEVER BEEN EASIER so get it for just £2 Amethyst Other Photographic Equipment 0 December 14th 03 03:28 PM


All times are GMT +1. The time now is 01:15 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 PhotoBanter.com.
The comments are property of their posters.