black dots on DNG raws (A590is)

shinnen

169

« on: 03 / August / 2015, 22:21:34 »

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Hi,
I'm trying to save raw files with my JPGs. It seems, from the menu, that I have a choice of crw/cr2, or dng; and I'm not sure which it the best format. When I save in dng, I get black spots all over the dng image. I suspect that this has something to do with badpixels; and have created the badpixel.bin file, which doesn't seem to help. The question is, should I be bothering with dng or simply saving in crw/cr2, i.e. which is better? And, if dng is preferable, how do I deal with the black spots?
Thanks,
..... john

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reyalp

14111

Re: black dots on DNG raws (A590is)

« Reply #1 on: 04 / August / 2015, 01:07:47 »

Quote from: shinnen on 03 / August / 2015, 22:21:34

Hi,
I'm trying to save raw files with my JPGs. It seems, from the menu, that I have a choice of crw/cr2, or dng; and I'm not sure which it the best format.

Generally, DNG is recommended. The "CRW" that CHDK creates is just a dump of the sensor with no meta data. It isn't understood by many programs, and those that do need to be updated for each new sensor.

Quote

When I save in dng, I get black spots all over the dng image. I suspect that this has something to do with badpixels; and have created the badpixel.bin file, which doesn't seem to help.

Did you also set the DNG version to 1.1? badpixel.bin is only used with DNG 1.1. In DNG 1.3, the raw software is supposed to take care of the bad pixels, but most non-adobe software doesn't support this feature.

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Don't forget what the H stands for.

shinnen

169

Re: black dots on DNG raws (A590is)

« Reply #2 on: 05 / August / 2015, 16:11:57 »

Thanks reyalp. That was the key, using version 1.1 of badpixel.
Now I no longer have the black spots.
I'm finding, however, that the dng file (which I'm opening in Helicon filter .... abobe plugin) is a tad overblown wrt colour vividness. This is easily rectified, but if you know of a setting I can use to fix it, that would be nice.
Thanks again,
..... john

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reyalp

14111

Re: black dots on DNG raws (A590is)

« Reply #3 on: 05 / August / 2015, 16:29:27 »

Quote from: shinnen on 05 / August / 2015, 16:11:57

I'm finding, however, that the dng file (which I'm opening in Helicon filter .... abobe plugin) is a tad overblown wrt colour vividness. This is easily rectified, but if you know of a setting I can use to fix it, that would be nice.

There aren't any CHDK options to control how the color is rendered, this is the responsibility of the raw processing software. There is a a color matrix in the code, but it's not simple to adjust.

I don't know anything about helicon specifically, but with many raw programs you can either create a camera profile or save settings to re-use with other images.

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Don't forget what the H stands for.

shinnen

169

Re: black dots on DNG raws (A590is)

« Reply #4 on: 05 / August / 2015, 16:57:23 »

Hi reyalp,
Sorry for not getting back to you in time. I removed, and reinstalled Helicon Filter. It's been acting a little strangely lately, and I thought it might be having problems showing the DNGs; and that was the problem. Now it's running well, and showing the DNGs fine.
Thanks again for your help.
...... john

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