Thanks for the Mobillight heads-up. I've never heard of them before but
I'll remember not to buy one. :-)
Chuck Norcutt
Tim Hughes wrote:
> <Good to see you back, Tim. >
>
> Hi Chuck,
> thanks, I have not been checking this list much lately, although I
> had some off list correspondence with some people about a few things recently.
>
> I have been playing with a Mobilight 300J Studio flash at the moment, which
> was a keh non working unit. Fairly simple unit which comes with a battery
> pack too, so you can use it away from the studio, off line. They have a
> rather dangerous high voltage connector on it, which you can easily stick
> your fingers in , if not careful. Quite amazing in a modern unit to have such
> a dangerous setup. I am going to change the connector ,so I can use it with
> Quantum turbo style cables as well.
>
> Tim Hughes
>
> --- On Tue, 5/5/09, Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx> wrote:
>
>> From: Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
>> Subject: Re: [OM] clever use of available sensor real estate
>> To: "Olympus Camera Discussion" <olympus@xxxxxxxxxxxxxxxxx>
>> Date: Tuesday, May 5, 2009, 4:05 AM
>> Good to see you back, Tim. It's been a long time since
>> one of these
>> insightful posts.
>>
>> Chuck Norcutt
>>
>> Tim Hughes wrote:
>>> I read their position paper and I think some of the
>> claims are
>>> overblown and maybe in some cases specious:
>>>
>>>
>> http://www.fujifilm.com/photokina2008/pdf/release/super_ccd_exr_e.pdf
>>>
>>> It looks like when running in 6Mpixel modes there are
>> some advantages
>>> in some ways, but not really in 12 mpixel mode. The
>> mode with
>>> increased dynamic range is an example where it maybe a
>> fairly good
>>> tradeof, but you land up in a mode pretty close to
>> 6Mpixel rather
>>> than 12.
>>>
>>> For example it appears the traditional beyer pattern,
>> which is
>>> optimised for highest resolution in green, since this
>> is human eyes
>>> peak sensitivity and peak sunlight wavelength, will
>> have higher
>>> horizontal resolution than the new exp pattern. This
>> actually even
>>> adds a little more since the eye/brain aparently also
>> subjectively
>>> percieves it to be highest reolution if it has
>> greatest resolution in
>>> the horizontal direction.
>>>
>>> The new exp patern is quite strange in that the
>> highest resolution in
>>> green is on the left diagonal , with all other
>> directions being
>>> lower! This is non-optimal since horizontal is best
>> subjectively. The
>>> beyer has equal, but reduced by 45% resolution on
>> both
>>> diagonals,while the vertical and horizontal are the
>> the highest and
>>> equal.
>>>
>>> The exr horizontal green resolution, is lower than the
>> beyer, at
>>> 12Mpix because of diagonal pattern. Because of the
>> unsymetrical
>>> spacing of exp, it also aliases at even lower
>> resolution than you
>>> would normally imagine from that raw color pixel
>> count. If you
>>> photographed a thin curved line object like a hair
>> say, it would
>>> produce some additional low frequency aliasing because
>> sampling was
>>> more non-uniform ,at different angles than beyer.
>> (think: if a line
>>> pair is sampled by two close spaced pixels then they
>> get resolved,
>>> but the next pair of pixels in exp are now more widely
>> spaced, so the
>>> next adjacent line pair is not resolved)
>>>
>>> The wide dynamic range option which is really more
>> like 6mpixel,
>>> since it selects best exposure from two diagonal
>> pixels, then has
>>> uniform sampling, at least at a particular brightness
>> level.
>>> The claim that there is less aliasing from binning
>> diagonally left
>>> adjacent pixels in exr, rather than more widely
>> separated ones
>>> (bayer), is complex to analyse and is more orientation
>> dependent than
>>> beyer.
>>>
>>> However, because the beyer samples at a higher
>> horizontal frequency
>>> than the non-uniform exr, then binning two horizontal
>> (or vertical)
>>> pixels in beyer, still has lower aliasing, since the
>> actual sampling
>>> was done at a higher resolution (frequency) thus
>> having lowest
>>> aliasing.
>>>
>>> The s/n ratio improvement is exactly the same for
>> equal area
>>> photo-diodes in the two technologies. In this
>> comparison for the
>>> bayer at 6mpixels, the optimal bining for best
>> subjective and actual
>>> resolution, would be combining vertical pixels.
>>>
>>> Tim Hughes
>>>
>>>
>>>
>>>
>>> --- On Fri, 5/1/09, usher99@xxxxxxx
>> <usher99@xxxxxxx> wrote:
>>>> From: usher99@xxxxxxx <usher99@xxxxxxx>
>> Subject: [OM] clever use of
>>>> available sensor real estate To:
>> olympus@xxxxxxxxxxxxxxxxx Date:
>>>> Friday, May 1, 2009, 2:12 PM
>>>>
>> http://www.dpreview.com/reviews/fujifilmf200exr/page2.asp
>>>> Moose might be amused that low light performance a
>> few generations
>>>> later still doesn't really exceed the
>> F30/31--the latter are still
>>>> expensive.
>>>>
>>>> Not many Moose sightings of late.
>>>>
>>>> A Trace Worried Mike --
>>>>
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