Image artefacts using fastReadoutMode

Once again, sorry if this is off topic here:

Using a Nano-M2590, I get this strange vertical artefact if fastReadoutMode is active:

Compare with result when fastReadoutMode is Off:

Is this inevitable, or is it related to some other property that needs modifying?

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Hi @Ben

This has to do with the Fixed-pattern noise of the cameras sensor and unfortunately, as far as I know, there is nothing you can do about it. The intensity can be affected by exposure time, gain or environment temperature.

Of course you can try to remove the artifacts by using a flat-field correction. :cvb: provides you with the CreateFlatfieldCorrectedImage function which is part of the :cvb: Image Manager.

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OK; so there’s going to be a tradeoff between transport and processing in there.

I haven’t managed to determine which dll I need to gain access to CreateFlatfieldCorrectedImage etc. from C#?

Yeah it’s not yet implemented in the new .NET wrappers, and it seems that it’s also missing in the old C-style .Net API… Atually it should be there :thinking:
I will follow up this matter and keep you informed!

In the meantime you can call the function directly from the CVCImg.dll Here is the signature:

cvbres_t CreateFlatfieldCorrectedImage ( IMG ImageIn ,
IMG ImageFlat ,
IMG ImageDark ,
double Gain ,
IMG & ImageOut

You can find it in the CVB documentation (%CVB%Doc/CommonVisionBlox.chm).

Don’t stress for me. The way it looks right now it’s going to be less hassle to just accept the limitations of not activating fastReadoutMode (though I have no idea what the performance penalty is).