SX40 HS noise issues - General Help and Assistance on using CHDK stable releases - CHDK Forum supplierdeeply

SX40 HS noise issues

  • 8 Replies
  • 3995 Views
SX40 HS noise issues
« on: 30 / April / 2012, 21:53:43 »
Advertisements
Maybe someone can give me an idea of what I am doing wrong with my settings or something as to why I am having such huge noise issues.

https://picasaweb.google.com/lh/photo/il3VLP12qhnxBNAtrgBWPiYEbQCJQWBRNxH9Tr84-ng?feat=directlink

https://picasaweb.google.com/lh/photo/HntRvm71FQ0Fvrcth5cTwSYEbQCJQWBRNxH9Tr84-ng?feat=directlink

<table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/HntRvm71FQ0Fvrcth5cTwSYEbQCJQWBRNxH9Tr84-ng?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/-4t855d2myaU/T5ieG-gW-9I/AAAAAAAAA_s/zuYJfEZhG4U/s144/SND_0102.jpg" height="108" width="144" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/103611472445026220209/20111128?authuser=0&authkey=Gv1sRgCLDIldLF0PKNYQ&feat=embedwebsite">2011-11-28</a></td></tr></table>

Re: SX40 HS noise issues
« Reply #1 on: 30 / April / 2012, 22:44:42 »
what was the exp.
and what was the iso set at?

*

Offline philmoz

  • *****
  • 3450
    • Photos
Re: SX40 HS noise issues
« Reply #2 on: 30 / April / 2012, 22:49:16 »
The images look underexposed with the exposure pushed way up in post processing.

You need to somehow capture more light.

If you want to capture star trails use a much longer exposure (and dark frame subtraction).
If you want to capture the night sky, capture multiple images and stack them (e.g. http://keithwiley.com/astroPhotography/imageStacking.shtml).

Phil.
CHDK ports:
  sx30is (1.00c, 1.00h, 1.00l, 1.00n & 1.00p)
  g12 (1.00c, 1.00e, 1.00f & 1.00g)
  sx130is (1.01d & 1.01f)
  ixus310hs (1.00a & 1.01a)
  sx40hs (1.00d, 1.00g & 1.00i)
  g1x (1.00e, 1.00f & 1.00g)
  g5x (1.00c, 1.01a, 1.01b)
  g7x2 (1.01a, 1.01b, 1.10b)

Re: SX40 HS noise issues
« Reply #3 on: 30 / April / 2012, 22:51:11 »
20 seconds and iso was set at 610. I also have noise like this in just normal photos I take, that arnt low light.


Re: SX40 HS noise issues
« Reply #4 on: 30 / April / 2012, 22:52:05 »
what do you mean pushed way up post processing?

*

Offline philmoz

  • *****
  • 3450
    • Photos
Re: SX40 HS noise issues
« Reply #5 on: 30 / April / 2012, 23:21:18 »
what do you mean pushed way up post processing?

It looks like you adjusted the exposure and/or brightness setting in whatever program you used to process the image.

Post the unedited JPEG from the camera for comparison.

Phil.
CHDK ports:
  sx30is (1.00c, 1.00h, 1.00l, 1.00n & 1.00p)
  g12 (1.00c, 1.00e, 1.00f & 1.00g)
  sx130is (1.01d & 1.01f)
  ixus310hs (1.00a & 1.01a)
  sx40hs (1.00d, 1.00g & 1.00i)
  g1x (1.00e, 1.00f & 1.00g)
  g5x (1.00c, 1.01a, 1.01b)
  g7x2 (1.01a, 1.01b, 1.10b)

*

Offline philmoz

  • *****
  • 3450
    • Photos
Re: SX40 HS noise issues
« Reply #6 on: 30 / April / 2012, 23:25:40 »
I also have noise like this in just normal photos I take, that arnt low light.

If you are processing RAW/DNG files from CHDK then you will see more noise than the camera JPEG because the files are saved before the camera does any noise reduction on the image.

You need to do your own noise reduction on the images in whatever tool you are using to process the images.

If you think the noise is excessive it would help to post the original camera JPEG and CHDK RAW/DNG files to a file share site (and post a link here).

Phil.
CHDK ports:
  sx30is (1.00c, 1.00h, 1.00l, 1.00n & 1.00p)
  g12 (1.00c, 1.00e, 1.00f & 1.00g)
  sx130is (1.01d & 1.01f)
  ixus310hs (1.00a & 1.01a)
  sx40hs (1.00d, 1.00g & 1.00i)
  g1x (1.00e, 1.00f & 1.00g)
  g5x (1.00c, 1.01a, 1.01b)
  g7x2 (1.01a, 1.01b, 1.10b)

Re: SX40 HS noise issues
« Reply #7 on: 02 / May / 2012, 10:50:27 »
those are the orignal raw dng files....


*

Offline philmoz

  • *****
  • 3450
    • Photos
Re: SX40 HS noise issues
« Reply #8 on: 03 / May / 2012, 00:37:01 »
those are the orignal raw dng files....

Where are the DNG files? The only files I can see linked to are JPEG images converted from the raw files.

To help understand what is going on we need actual sample .DNG and .JPG files direct from the camera without any processing. You will need to upload them to a file sharing site like box.com and post the link here.

It would also help to understand your workflow when processing the raw files, what editor are you using, what settings etc.

Phil.
CHDK ports:
  sx30is (1.00c, 1.00h, 1.00l, 1.00n & 1.00p)
  g12 (1.00c, 1.00e, 1.00f & 1.00g)
  sx130is (1.01d & 1.01f)
  ixus310hs (1.00a & 1.01a)
  sx40hs (1.00d, 1.00g & 1.00i)
  g1x (1.00e, 1.00f & 1.00g)
  g5x (1.00c, 1.01a, 1.01b)
  g7x2 (1.01a, 1.01b, 1.10b)

 

Related Topics


SimplePortal 2.3.6 © 2008-2014, SimplePortal