I have an Olympus E-PL2 and am taking photos in raw. I have the codec downloaded from Olympus, so I can view the photo with Picasa in Windows, and it looks fine but a few seconds after loading the image, it goes and does something in which it looks like it desaturates the whole photo. What is going on? I know there are many posts asking 'what is a good raw viewer' but I'm looking more for a solution for Picasa if possible since I use it for all my photo management.

  • I agree that this is effectively a duplicate (because the same thing happens in other software), but that one is specific to Lightroom and this one to Picassa.
    – mattdm
    Jan 8, 2012 at 3:28
  • indeed, i found it difficult to describe the 'problem' and didn't see a suggested match as I was posting my ?
    – pyInTheSky
    Jan 8, 2012 at 4:08
  • 1
    another similar question
    – nuc
    Jan 10, 2012 at 18:31

6 Answers 6


Sorry but you are confused. Picasa first shows you the JPEG preview that is embedded in RAW files.

It then loads the RAW data and lets it be converted by the codec. What you see then is the RAW file with default convertion.

In order to get something good from a RAW file, you have to work at it. IIRC there are questions here regarding matching the JPEG conversion and about why RAW files do not look so good by default.

  • 1
    Like this one: How can I reproduce the camera-internal postprocessing?
    – mattdm
    Jan 7, 2012 at 21:44
  • P.S.: +1 to this answer, but I don't think being confused is anything anyone has to be sorry about. :)
    – mattdm
    Jan 7, 2012 at 21:45
  • I'll accept your answer, but it's odd that you say it shows me the jpg and then the raw. I took the advice of another questioner and installed faststone image viewer, and the raw preview looks great, nothing at all like the picasa preview. Is it actually showing me a jpg preview and not the raw?
    – pyInTheSky
    Jan 8, 2012 at 3:57
  • 1
    Yes, the image shown is the embedded JPEG which is not ambiguous to render. The desaturation happens because colors and tones of RAW can be interpreted differently.
    – Zak
    Jan 10, 2012 at 1:40

Most RAW photos include a JPEG thumbnail (which is what you'll see initially); Then Picasa runs the RAW decoding (with different parameters to your camera), giving you your desaturated image.


We have this same question for Apple Aperture, Adobe Lightroom, Adobe Camera RAW, and possibly others I haven't found right now. In each case, the answer is the same: there is no such thing as displaying an "unedited RAW file". By definition, a RAW file is sensor data not in a useful form for display. The closest you might get is an RGBG matrix with linear color, which might look kind of like an image if you stand back and squint. Instead, what you're seeing initially is the embedded JPEG preview, and then when the preview changes, you're seeing the default conversion.

If you don't like the defaults, you can change them in most programs. In Picasa, I'm not sure you can very much.


One of the possible issues here is colour management. The raw rendition which you see after the initial delay may have no embedded profile, or you may need to set Picasa Color Management to "on" in View menu. It may be both issues, too.


It will be showing the jpeg preview (a jpeg preview is embedded in each raw file) until the RAw file fully loads up. All raw files need a little PP in order to look anything like the jpegs you get out of camera.

I remember it used to annoy me!


Picasa does not use the camera's settings for conversion of the RAW but instead its own algorithm. It is one of the worst converters out there, but you get what you pay for.

I started using Irfanview and have been quite happy with it. Picasa is where I do my organization.

  • The RAW data from different cameras, even from the same manufacturer, varies wildly in terms of colour points and more, and it's quite a task for any RAW editing software to support them all equally well. Picasa may have poor results in some cameras and great results in others. Other editors may have poor results in other cameras and great results with your camera. Big players like Adobe usually support all cameras (made up to the date the RAW editor was released) very well which is great if you have something like a recent version of Lightroom. Aug 5, 2013 at 5:34

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