CR2 files of star images are very noisy

[Sameer]

Hi

Recently upgraded to Windows 10 and have just installed Irfanview as it has been my preferred image viewer for a long time.

I am encountering and issue when displaying raw CR2 files of star images - they appear very overexposed and very noisy. An example is attached. This issue did not exist on Windows 7, the files themselves are fine and display at a normal level of exposure on Windows 10 default image viewing software, as well as in the software I use to process them. Irfanview also correctly displays images that are not of stars - I assume this is because irfanview is attempting to correct range and is treating the star images as being dark images that need to be brightened, and there's probably some tick box I need to untick to alleviate this issue. But that's just my assumption.

Windows 10 64-bit, IV 4.57.

[Bhikkhu Pesala]

The attached image is a JPG image. We need the original CR2 file. Check your IrfanView Settings, for Plugins. You may be loading an embedded preview image or half sized image. File types not supported by the forum can be uploaded to filebin.net or DropBox, and a link added to your post.

[Jacal]

The current version of IrfanView can not display the embedded jpeg images from CR2 photos, it looks to be a bug - link. What you see, is the actual raw image (half-sized, if I remember correctly), which is supposed to be noisy and distorted and 'weird'. I did not report this to the developer, I have switched to the previous version. I am sorry for that.

[Sameer]

The attached image is a JPG image. We need the original CR2 file. Check your IrfanView Settings, for Plugins. You may be loading an embedded preview image or half sized image. File types not supported by the forum can be uploaded to filebin.net or DropBox, and a link added to your post.

Hi, I have attached the RAW file here ; https://filebin.net/gfqckg0sqr963coa

I have also attached two other files - one is how IrfanView displays the image (and also how it saves is as a jpeg) and the other is how it is displayed in any other software.

[Sameer]

The current version of IrfanView can not display the embedded jpeg images from CR2 photos, it looks to be a bug - link. What you see, is the actual raw image (half-sized, if I remember correctly), which is supposed to be noisy and distorted and 'weird'. I did not report this to the developer, I have switched to the previous version. I am sorry for that.

Is my post above similar to the issue you experienced? Would you recommend stepping back to 4.56?

[Bhikkhu Pesala]

If I don't try to load the embedded preview image, the full sized image loads, but it is still very noisy, as in your screenshot.
Try to use the Canon plugin gives an error.

I recommend using a different program for working with RAW image, one that is designed for the task. IrfanView is a swiss army knife, when what you need is a proper screwdriver.

[Sameer]

If I don't try to load the embedded preview image, the full sized image loads, but it is still very noisy, as in your screenshot.
Try to use the Canon plugin gives an error.

I recommend using a different program for working with RAW image, one that is designed for the task. IrfanView is a swiss army knife, when what you need is a proper screwdriver.

IrfanView used to work fine and I am used to its interface for navigation/zoom etc. I don't use it to process the images, just to view them.

Would a previous version of IrfanView work?

[Bhikkhu Pesala]

I installed IrfanView 4.56 32-bit with its plugins in C:TEMP\IrfanView 4.56\ and the image looked mostly black, as in your Normal screenshot. I guess the thing to do is revert to 4.56 if that best suits your needs, and submit a bug report to Irfan Skiljan. Let us know what he says.

[Jacal]

@Sameer: As said, ver. 4.57 is broken, it can not display the embedded jpeg images from CR2 files, which should be the default behaviour. These embedded images are heavily processed in-camera, with curves, noise reduction, sharpening, lens distortion correction etc. applied after demosaicing the raw data. The editing "recipe" is written in the metadata, that only the Canon's raw editor, DPP, can read. The raw image itself looks ugly and noisy: Eek! Your 'normal' and 'irfanview' samples are both OK, the first one being a jpeg preview and the second one the raw image, rendered via the raw plugin. There is nothing wrong with your CR2, it is a bug in the new IV version. (Don't try the old crw plugin, it only supports some very old camera models.)

@Bhikkhu Pesala: I see no way to load the preview file; can you, please, try with my testing cr2 file: link (29,5 MB). It has actually "this is jpeg" written on the preview.