iView Media Pro - Why does the Compression reading change for similar photos?

[DavoMrMac]

So many questions, and I thought this one might also need some help from an iView user.

With my Canon 20d some of the JPEGS are 1.9Mb, some 2.2Mb, some even 2.5Mb. The RAW files range from 7Mb to 9.7Mb. The only thing that may have been changed is my aperture setting, but in some cases this is the same and the file sizes still differ.

In iView Media Pro, there is a listing under the images information called 'Compression' and this differs from like 1:6 to 1:16, with the JPEGS having a higher amount of compression.

Why does iView report the compression ratio as different on images that were shot with the same settings? any help is appreciated.

[PacAce]

Compression is not a function of the camera setting used but the actual content of the file.

[DavoMrMac]

PacAce, thanks for the reply.

Just been admiring your retouching of an image on another thread - excellent job.

Your response to my question, I do not fully understand (sorry). Could you explain in a bit more detail with perhaps an example so I can get my head around it.

Thanks.

[PacAce]

PacAce, thanks for the reply.

Just been admiring your retouching of an image on another thread - excellent job.

Your response to my question, I do not fully understand (sorry). Could you explain in a bit more detail with perhaps an example so I can get my head around it.

Thanks.
Thanks for the complement.

Re the JPGE compression, instead of my trying to explain it, I think this link will do a better job of it:

http://www.photo.net/learn/jpeg/

[DavoMrMac]

Thank you, greatly appreciated.