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[OM] Sixteen What? [was Does software choice matter in producing image "

Subject: [OM] Sixteen What? [was Does software choice matter in producing image "quality" ?]
From: Moose <olymoose@xxxxxxxxx>
Date: Thu, 12 Dec 2013 14:36:15 -0800
On 12/12/2013 4:29 AM, Brian Swale wrote:
> ...
> I guess I'm an unashamed heretic.
>
> FastStone does almost all I want to do to/for images.
>
> Really, the only aspects of what Moose does to images that I am envious of, 
> since FastStone
> can't do them, are context-aware cloning, and selective sharpening which 
> Moose used to
> excellent effect on the wedding shots of one of our members.

And yet:

1. There have been many complaints from the South Island about image 
limitations attributed to cameras and film that are 
not echoed by others using the same tools to capture images, but more capable 
ones to process them.

As one example, you often comment on how it's necessary to have overcast 
conditions for good images of things like 
flowers. As before, I disagree, on two grounds. First, with proper technique 
and software, it simply isn't true. Second, 
flowers in shade or cloudy conditions look just like the subjects in those 
conditions, and not at all like they do in 
the sun. To shoot JPEGs (8 bit) and process in 8-bit software is to be 
endlessly running into unnecessary highlight 
problems.

2. Those others here who actually make images for the public to view and/or 
purchase all use quality programs that edit 
in 16 bits.You aspire to sell prints, but eschew doing what others do in order 
to do so.

> I have no practical knowledge of the differences between 64, 32, 16, and 
> 8-bit images.
>
> I really don't know what my machine works in. I wouldn't know where to look 
> to find out ...

You are confabulating two different things. Your computer has a 32 bit 
processor and your operating system is 32 bit. So 
is mine, although I'm moving up to 64 bit soon.

Digital images may be represented using 8, 16, or, rarely, 32 bits of data for 
each color (which is unrelated to the 
word size of the hardware and OS). JPEGs and converter/editors like FastStone 
use 8 bits. That allows 256 different 
values between pure black and the brightest color in each channel (red, green, 
blue).

Although enough for many subjects, there are numerous others, the brightness 
range of which cannot be contained in 256 
values. Your Oly E-cameras capture 14 bits of brightness value, 16,384 possible 
values for each color. The JPEG 'engine' 
in the camera has to decide how to do a combination of compression and clipping 
to squeeze then into 256 values. You may 
give some them guidance as to how you want it done with camera settings.

They generally do quite a remarkable job, but throw away a lot of data. Even if 
they've done a great job, the problem 
comes when one makes adjustments to the tones. Brightness, Contrast, Levels, 
Curves and other adjustments stretch or 
squish parts of the tonal range. Without intermediate values available, values 
can only increase or decrease to the next 
coarse value. The result is a histogram with spikes where ranges have been 
compressed, and empty values/gaps where 
stretched. A little of this often is not noticeable. But at some point, things 
start to look wrong.

With unsophisticated Raw conversion directly to 8-bit, such as available in 
FastStone, you have the same problem, but 
without the more capable, camera specific, knowledge of the camera's JPEG 
engine.

> In my limited experience, when it comes to appreciation of images for 
> framing, most
> members of the public couldn't give a rat's "a" about extreme sharpening 
> excellence -
> although most can tell if an image has been spoiled by excessive sharpening.

You misunderstand. I do like images with fine detail to have that detail clear, 
but that's all after getting the 
tonalities right for my taste. I have a handicap, in a way, with much more 
acute vision than most. When I look at the 
world, it has more sharp, clear detail than when you look at it. I know, 
because I can cover my right eye, and see with 
'only' 20/20 visual acuity. I actually usually do sharpening after downsizing 
for the web, then back off, to partially 
compensate.

This is reflected in my images, for better or worse. But 16 bit image editing 
is not about sharpening, it's about tonal 
qualities.

> And I have unfortunately never seen one of Bob Whitmire's prints.

A shame. He has great skill in retaining fine detail while the overall image 
may have soft qualities. A print of his I 
have of boats at anchor on a foggy day is extraordinary in that regard. But 
that's prints, which is a different kettle 
of fish than web images. Unfortunately, I've not seen any of your prints, 
either, and must do with web images, at least 
for now.

> You've only got to go to painting art to realise that extreme sharpness in 
> that medium is a
> negative aspect of quality.

A matter of taste. There used to be one almost photo realistic painting of a 
still life centered around a violin in an 
SF museum that I liked very much. Then again, some very unclear Monets please 
me.

I do occasionally show here photos that I hope have a painterly quality, often 
unsharp. I am interested in such things. 
But they are different mediums, and different things may be done in each.

There are successful styles of photography which are not sharp at all, or have 
wildly skewed tonalities. But your 
preferred subjects, at least that I have seen, are the sort of subjects where 
most buyers expect reasonable clarity of 
detail and natural colors.

> Many times other aspects of an image, such as composition, use of colour, 
> placement of
> out-of-focus elements (for example) are much more important.

I agree completely.

> Occasionally I will shoot RAW if I think that the range of exposure inside a 
> frame will be
> beyond what the sensor can cope with (if I remember to notice this).

I believe you mean 'greater than may be rendered in a JPEG'

> Mostly I have learned to avoid such situations, and select for this these 
> days without thinking.

As above, that is not necessary, with proper equipment, software and technique 
- and renders a different sort of image. 
That's fine, if you are happy with such am unnecessary limitation on your 
subjects.

> As far as I can recall, not once have I been successful in rescuing such an 
> image using a
> RAW converter etc.  So I don't waste my time doing it..

I'm not surprised, using crap converters and giving up. (Yes, unfortunately 
Oly's Viewer converter is hopeless with 
highlights.) You've seen how much highlight detail I've been able to pull out 
of a few of your images already limited by 
being JPEGs and then processed in a clumsy editor.

You might not believe what may be done with proper exposure and a good 
converter.

> For more than 98% of my images I shoot jpg.

A choice that limits what you can do.

> Back into cave.

Too dark in there! :-)

Sun Lit Moose

-- 
What if the Hokey Pokey *IS* what it's all about?
-- 
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