D700 DxO RAW high iso artifacts

[tom_johnson11]

<p>Hi,<br /> I recently converted from a D300 to the D700. I shoot RAW and convert with DxO 5.3.1. At high iso (6400), the RAW conversion reveals/creates artifacts in the shape of little black dots. Has anyone else encountered this problem? Is it specific to DxO? Is there something wrong with my D700?<br /> <br /> Thanks for help!<br /> Tom</p>

[tom_johnson11]

<p>Here is an example at iso 6400, 100% magnification.</p><div></div>

[michael_alger]

<p>I also use DxO 5.3.1 and I have not seen these artefacts from my D700-6400Iso files yet. as tehre is not so much structure visible on your crop, could it be that you just exaggerated sharping?</p>

 

[elliot1]

<p>Check your original photo to see if you have any hot pixels. I have noticed that DXO sometimes turns them black as in your sample shot. At ISO 6400, the D3/D700's can have numerous hot pixels. If you could post the original RAW crop next to your DXO shot, it may be useful.</p>

<p>It could also be from a combination of overly aggressive noise reduction and sharpening settings. Which DXO preset did you use. Have you tried their new High ISO preset?</p>

<p>You can also send your sample image to DXO for analysis throug email or post the question on their public forum.</p>

[sprouty]

<p>I'd be more worried about those giant orange circles...</p>

[tom_johnson11]

<p>Michael - I do see it without aggressive sharpening as well (I noticed these first when I had sharpening turned off). You are right though in that sharpening makes them more visible, but I don't think that is the main problem.</p>

<p>Elliot - Noise reduction was actually quite low. If I reduce it further, the spots actually tend to become harder to see because the entire image becomes more noisy. I just used the standard the preset. <br>

I don't think it's hot pixels because these spots show up in different places for each picture.</p>

<p>Sp - :)</p>

<p>Overall, I am beginning to wonder if this is specific to my D700 as none of you appear to have suffered from this. </p>

[sprouty]

<p>Unfortunately I would tend to agree that it was your camera since they don't seem to be linked to a highlight or other artifact of the image and especially since they are moving around from shot to shot. <br>

But a simple method to confirm this would be to download a different RAW converter (I think most offer 30-day trials). Then if you still have the issue it's the camera, and if you don't, it's related to DXO.</p>

[elliot1]

<p>Tom, Can you post the identical crop from your original shot? does it have spots? Are the spots there in your original shot or only in the DXO processed shots?</p>

[elliot1]

<p>Tom, assuming the spots are not in your original shot, I suggest you try the High ISO preset and compare the results.</p>

[tom_johnson11]

<p>So part of the problem appears to be the camera, the other part might be DxO. I ran the files on Capture 1 (demo version) and no spots appeared. Yet you can see little marks if you know where to look in the processed Capture 1 file, and these turn into more visible black dots in DxO. So it is possible that something is wrong with sensor and that various software handle this differently - with DxO they become rather noticle black dots. I will contact contact DxO with this problem to see what they say. I ended up exchanging the camera for and new one which hopefully will work well.</p>

[tom_johnson11]

<p>For those how may still be following this, DxO replied that the problem was indeed a multitude of dead pixels. Their noise reduction made the dead pixels more apparent at high ISO. They also stated that their own D700 suffers from dead pixels, but much fewer than the one my camera had. </p>