| Author | Thread |
|
|
09/06/2007 06:58:55 PM · #1 |
I noticed yesterday that when I increased the ISO on my 400D (in fine jpeg mode) the number of remaining frames decreased.
Just fired some test shots, keeping the exposure the same by increasing the shutter speed, and on ISO100 the file size is 1.97MB and by ISO1600 the same image is at 3.24MB.
Anybody know why this is the case? I am intrigued... |
|
|
|
09/06/2007 07:00:22 PM · #2 |
don't you think it takes space to store noise too.
:-))
Message edited by author 2007-09-06 19:00:32. |
|
|
|
09/06/2007 07:04:35 PM · #3 |
| It actually takes relatively much more space to store noise than image "content" because noise doesn't compress nearly as well. Which explains both the ISO effect on file size and also the NoiseNinja/NeatImage effect on file size, which goes in the opposite direction. |
|
|
|
09/06/2007 07:06:01 PM · #4 |
I never noticed this, I'm off to give it a try.
|
|
|
|
09/06/2007 07:07:31 PM · #5 |
| Ah, ok yeah. That makes sense. Although, doing the same thing in RAW the difference is less but still there (7.83 vs 8.44) I thought RAW files were uncompressed? |
|
|
|
09/06/2007 07:11:33 PM · #6 |
Originally posted by latentflip:
Ah, ok yeah. That makes sense. Although, doing the same thing in RAW the difference is less but still there (7.83 vs 8.44) I thought RAW files were uncompressed? |
Canon RAW files use lossless compression, which is of course less aggressive than lossy compression. So the effect is less, but still there. For instance, I have RAW files all the way from 8.4MB to 16.9MB. |
|
|
|
09/06/2007 07:14:13 PM · #7 |
| Bam, cheers kirbic I can sleep easy now. |
|
|
|
09/06/2007 07:18:41 PM · #8 |
If you change ISO and the first image has a blown out area (say blacks) and the second one shot at a higher ISO doesn't, then the second will compress less (be larger) because there's more detail in the photo.
This could be impacting file size.
|
|
|
|
09/06/2007 07:25:13 PM · #9 |
Originally posted by kirbic:
I have RAW files all the to 16.9MB. |
Braggart! ;) I can only get around 10.2MB!
Sorry for taking your quote out of context. |
|
|
|
09/06/2007 07:38:24 PM · #10 |
Originally posted by Dr.Confuser:
If you change ISO and the first image has a blown out area (say blacks) and the second one shot at a higher ISO doesn't, then the second will compress less (be larger) because there's more detail in the photo. |
What Philip was saying is that the image capacity was changing on the status screen. It was being lowered, thus, the deduction was that the higher the ISO, the larger the files. This is before any images are captured.
Message edited by author 2007-09-06 19:39:17.
|
|
Home -
Challenges -
Community -
League -
Photos -
Cameras -
Lenses -
Learn -
Help -
Terms of Use -
Privacy -
Top ^
DPChallenge, and website content and design, Copyright © 2001-2025 Challenging Technologies, LLC.
All digital photo copyrights belong to the photographers and may not be used without permission.
Current Server Time: 12/30/2025 11:16:04 AM EST.
