Neat Image Calibration Images for Canon Rebel XT.

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ranjit - 25 Dec 2005 19:49 GMT

Hi guys,

I am trying to shoot the calibration target image from the Neat image
software to make a noise profile from RAW. The one available there
works for adobe camera raw, but I use capture one. I saw some one by
name of Alan Bremner who made that profile which has 93% to 96%
quality. The ones which I make are not crossing 74% at all Sad

I found some posts in this forum with the person with same name so I am
hoping it is the same person and he can help or if there is some one
else here who has done calibration image shots on canon rebel xt, can
you please explain how you went about it or even better if you can send
the RAW images taken so that I can convert and make the right profile,
i would greatly appreciate it.

Thanks,
Ranjit

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Alan Bremner - 27 Dec 2005 16:49 GMT

>I am trying to shoot the calibration target image from the Neat image
>software to make a noise profile from RAW.

Hi,

I printed the calibration target onto thin card and photographed that
at the various combinations of ISO/shutter speed that I required. I
taped or pinned the target to a wall and used a tripod to ensure some
consistency, and took care to make sure that the target was slightly
out of focus as recommended. The latter isn't easy at small apertures
so I shot quite a few images indoors by available light in order to
restrict DoF.

>The ones which I make are not crossing 74% at all Sad

I found that using the manual fine-tuning adjustments gave better
results than the auto-calibration. The latter method often resulted in
75-85% quality whereas a spot of fine-tuning often increased this
significantly.

>can you please explain how you went about it

I hope the above helps. The most important thing appears to be the
defocusing to prevent paper texture confusing the calibration process.

>or even better if you can send the RAW images taken so that I can
>convert and make the right profile, i would greatly appreciate it.

I wish I could! Unfortunately I lost them a few weeks ago in a hard
disk crash and because they weren't 'proper' photographs I had never
included them in my backup regime.... :-(

Al

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ranjit - 28 Dec 2005 20:04 GMT

Thanks Alan,

Let me give it a shot again. Hopefully this time I might get good
results. I didnt get what you meant by "A spot of fine-tuning". Did you
do anything special than selecting the region on the image manually ? I
mean did you use any of the bars on the right hand side ?

Thanks,
Ranjit

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Alan Bremner - 28 Dec 2005 23:55 GMT

>I didnt get what you meant by "A spot of fine-tuning". Did you
>do anything special than selecting the region on the image manually ? I
>mean did you use any of the bars on the right hand side ?

I used 'Auto Profile with Calibration Target' initially, and if I
wasn't satisfied with the resulting profile quality used the 'Fine
Tuning Analyzer. To do this I looked for noise frequency sliders that
showed yellow (or red), tried to find an area on the target that
corresponded to at least one of the RGB values for that frequency, and
then used 'Auto Fine Tune'. If I couldn't achieve "green" for all
frequencies I then used 'Auto Complete' to make a best-guess
extrapolation of the data before saving the profile with a meaningful
name ( see
http://www.neatimage.com/ug5/E-Device-noise-profiles/3-Preparing-profile-set-for
-different-device-modes.htm
for an excellent guide to organising the profile set).

I hope this makes the process a bit clearer.

Al

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