Am 06.11.2012 20:42, schrieb MichaelJF:
> Thomas de Groot <tho### [at] degrootorg> wrote:
>> On 5-11-2012 20:13, MichaelJF wrote:
>>> No need to blush;-) I only thought that my cheap trick could interest you
>>> regarding your former profession.
>>
>> Oh, absolutely. In fact I have been thinking about the contour line
>> possibilities for a long time without getting very far. So, I see great
>> possibilities in your technique.
>
> Thanks, I just investigate if exr-pictures can achieve an improvement after
> having reached a certain approximation of the landscape with png.

While OpenEXR will give you an improvement, it would still be a 
comparatively poor choice, as its absolute precision varies considerably 
between dark and bright regions of an image, so you'd have different 
quality on high plateaus than in low plains.

For your purposes, any classic file format with a 16-bit color depth 
would be better suited, such as 16-bit png.

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Am 06.11.2012 21:17, schrieb MichaelJF:
>> Thomas de Groot <tho### [at] degrootorg> wrote:
>>> (3) average the blurred object image
>>> with the scene image.
>
> Second thought: average the images with the transparent background and layer the
> result over the original scene only. Otherwise the original scene (background)
> has a chance to come into the object in motion. Ok, may be only to a small,
> hardly visible amount...

No, you're perfectly right there: averaging is the wrong operation for 
this job; you do want an overlay operation.

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clipka <ano### [at] anonymousorg> wrote:
> While OpenEXR will give you an improvement, it would still be a
> comparatively poor choice, as its absolute precision varies considerably
> between dark and bright regions of an image, so you'd have different
> quality on high plateaus than in low plains.
>
> For your purposes, any classic file format with a 16-bit color depth
> would be better suited, such as 16-bit png.

Many thanks, it's just an experiment. And I see I have still much to learn,
again. But this is one reason I try to make pictures with POV, I learn. By
observation or even by being corrected for errors or misjudgements by this
wonderful community.

Best regards,
Michael

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On 6-11-2012 21:43, clipka wrote:
> Am 06.11.2012 21:17, schrieb MichaelJF:
>>> Thomas de Groot <tho### [at] degrootorg> wrote:
>>>> (3) average the blurred object image
>>>> with the scene image.
>>
>> Second thought: average the images with the transparent background and
>> layer the
>> result over the original scene only. Otherwise the original scene
>> (background)
>> has a chance to come into the object in motion. Ok, may be only to a
>> small,
>> hardly visible amount...
>
> No, you're perfectly right there: averaging is the wrong operation for
> this job; you do want an overlay operation.
>

Hmm yes. That is true. Not as straightforward as I thought. And if some 
element of the scene partly obscures the moving object both techniques 
won't work correctly. But otherwise an overlay would do.

We still need a megapov-type piece of code in the software.

Thomas

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