How does dynamic range affect midtones?

[jimrichardson]

I know that high dynamic range will help capture a bigger range of tonal values from a scene, does that mean that there are more detailed gradients in the image as well as having more on the end?

Is it what gives drama to images like these:
http://media.timeoutsingapore.com/co...to-482x298.jpg,
http://1.bp.blogspot.com/-IRA-IJ9XsN...Photo+2013.jpg,
http://fast.swide.com/wp-content/upl...horizontal.jpg

compared to this photo of some beans I took on my iphone 5s: .

Subject matter aside, while my photo seems to be quite high in contrast and saturation, it lacks something I don't have a term for. Is it something about the equipment or something done in post?

[Dave Humphries]

Welcome to the CiC forums Jim,

I have changed the images that weren't yours to links, since I suspect you don't have the photographers permission to reproduce them here.

I know that high dynamic range will help capture a bigger range of tonal values from a scene, does that mean that there are more detailed gradients in the image as well as having more on the end?

In a word - no, because by the time you are viewing them on paper or screen, the dynamic range is reduced to no more than 4 or 6 stops. That is an over simplified answer, hopefully someone can improve on it for you.

Subject matter aside, ~

I think the subject matter is relevant to our perception of how powerful an image is.

~ while my photo seems to be quite high in contrast and saturation, it lacks something I don't have a term for. Is it something about the equipment or something done in post?

It is partly equipment related, but arguably could be improved in post production, yes.

As you say, looking at the histogram shows your image has a full tonal range, but sadly (being blunt) it just isn't a good composition, everything is in focus (due to the small sensor), so it just doesn't appeal.

Local Contrast Enhancement (LCE) is something you could apply to it to improve matters, but it still won't make it a great image I'm afraid. It will increase the contrast in the mid-tones though.

Hope that's helpful,

[jimrichardson]

Thanks Dave, that's useful. Don't worry, I make no claims as to the artistic value of my beanstalks, just something I had on hand as a reference for something that looked average. I'm just after terms I might use to describe the differences between my photo and the press photos and which bit of the process is most important for changing them.

[Dave Humphries]

I'm just after terms I might use to describe the differences between my photo and the press photos and which bit of the process is most important for changing them.

I think you need to compare apples with apples, not apples with beans

Can you find a good picture (on the web) of something you have in your garden, then take the closest possible matching shot with your phone, or a better camera?

Try to get same lighting, distance, angle of view, etc.

[MrB]

I'm just after terms I might use to describe the differences between my photo and the press photos and which bit of the process is most important for changing them.

Some of the words you might apply are 'impact' and 'power'. Although related, I would suggest that impact is the visual effect that the image has to attract the viewer's attention at first sight, and power has more to do with its emotional effect, both initially and after thoughtful study.

Both impact and power can depend upon the subject of the photo, and will be affected by the parameters used in capturing the image, as well as by adjustments made during processing. However, I suspect that the power of the linked press photos depends more on their content, so perhaps it is more difficult to create a powerful image from a capture of mundane content?

E.g. For me, this edit of "Some Beans" is no more powerful, but does seem to have more impact:



Just a few thoughts from a learner.

Cheers.
Philip

[Dave Humphries]

Hi Philip,

That's a good re-work and Jim could flick between the two images in Lytebox (click on an image and use left/right arrow keys alternately) to compare the two and work out what you have done to improve "bean impact" in your edit.

I see at least 4 main things and since Jim's question was about terminology, I will list them;
crop (good to remove extraneous, non-contributory image elements)
vignette (good to concentrate the viewers attention on the subject)
selective blurring (also good to concentrate the viewers attention on the subject)
selective LCE (always good to separate the subject from the bg (background) if done selectively

... there may be others.

Thanks,

[MrB]

...I see at least 4 main things and since Jim's question was about terminology, I will list them...

...there may be others.

Thanks,

Thank you, Dave, and there is just one more main one -

selective saturation (decrease foreground/background, increase subject -also to concentrate the viewers attention on the subject).

Cheers.
Philip

[Dave Humphries]

Thank you, Dave, and there is just one more main one -

selective saturation (decrease foreground/background, increase subject -also to concentrate the viewers attention on the subject).

Yeah, I did wonder about that too, but wondered if what I was seeing was caused solely by the selective LCE.

oh well 4/5 isn't bad, that's 80%

Cheers,

[Colin Southern]

Hi Jim,

I had a quick look at the linked references. Couple or 3 things going on here:

1. Powerful & dramatic images like these draw a lot on strong contrast; in technical terms that means using the full tonal range that's displayed or printed. If you looked at any of those I'm sure you'd see significant areas that were clipped to pure black and significant areas that were clipped to pure white, thus using the full range of levels available. With the blacks and whites clipped a midtone slider "simply" adjusts the gamma to shove the midtones up or down the histogram.

2. I hear you ask "how does that relate to dynamic range?" Short answer is "it doesn't really". People need to realise that dynamic range is a capturing exercise (to CAPTURE the information required) and then a processing exercise to squish them into something we can see (not much good if a camera captures 12 stops and we can only print 4 unless we can compress that range and still have it look good). Generally people don't realise that even an HDR image STILL needs to be processed as a normal image once the DR has been compressed into something we can display or print - ie once you've got the image to the point where the deep shadow detail and highlights are all showing, you STILL need to set correct black and white clipping points, and correct midtones (gamma). HDR just makes it harder because it's easy to technically make these things fit, but much much harder to make them fit and look good (I've seen many images that just don't loot right because the sky it the same luminocity as the foreground); That comes down to local contrast (as Dave mentioned), which can be a "black art" in itself.

3. Other things "make parts of an image stand out" - it's a long list, but some of the things are ...

- Vignettes draw the eye towards the centre and give the illusion of targeted lighting

- Selective colour (partially or completely) (inc to de-emphasise things that are drawing the eye for the wrong reasons)

- Contrasting "beauty" with "ugly" (eg pretty girl in engineering workshop, or posed on a pile of rubbish)

- In and out of focus

- Leading lines

- Diagonals

Hope this helps.

[jimrichardson]

Thanks for your replies guys. As per your suggestion Dave, here's a photo of my mother taken on my iphone, the same photo with some blurring and contrast applied and some links to photos I found on flickr that have the aesthetic I'm trying to find the terms to describe. I tried to select ones that are similar, so just using available light for the most part.




https://www.flickr.com/photos/256411...-7sLuBX-62chxB
https://www.flickr.com/photos/mytrip...-9gttcX-iavrSu - really like the strength and vividness of this one
https://www.flickr.com/photos/anacor...-8NWj2u-dL5jpt
https://www.flickr.com/photos/jonsie...-e3eAVX-9Ph5JB - this has a slightly different mellower feel to it, something done in post?
https://www.flickr.com/photos/images...-gRpwh7-7ARX6m - this one especially seems to have the great gradient on her scarf

[Richard Lundberg]

Second one is a bit harsh. Look into something like Perfect Portrait.

[Colin Southern]

The 2nd one looks to have good tones to me, but is too soft overall, and the eyes need lightening.

[jimrichardson]

The 2nd one looks to have good tones to me, but is too soft overall, and the eyes need lightening.

Thanks guys. Would anyone be able to tell me the technical differences between my photo and the photos I found on flickr? I don't expect to be able to achieve any of this on an iphone, just using it as a reference for a low quality photo.

[Dave Humphries]

Thanks guys. Would anyone be able to tell me the technical differences between my photo and the photos I found on flickr? I don't expect to be able to achieve any of this on an iphone, just using it as a reference for a low quality photo.

Jim, I'm afraid I am going to have to refer you back to my earlier answer (with slight edits);

I think you need to compare apples with apples, not apples with oranges

Can you find a good picture (on the web) of something you have in your garden or locale, then take the closest possible matching shot with your phone, or a better camera?

Try to get same lighting, distance, angle of view, etc.

However, as that didn't work last time - let's try a different way.

I think what you are actually asking is
"what are the technical differences between an iPhone camera and a 'proper' camera?"

That is a bit easier to answer:
Assuming a typical DSLR is a proper camera, that will have:
A MUCH larger sensor, which will bring these advantages;

More resolution = sharper pictures
Lower noise = no digital snow in the darker areas of an image, especially when light levels are low
RAW capture = much more post processing capability before problems occur (e.g. posterisation, clipped shadows, blown high lights)
More control of Depth of Field (DoF) = it is much narrower with a larger sensor

Better (larger) lenses = less flare, less optical distortions, more light capture
Allow automatic, semi-automatic and manual control of camera and lens settings so you can, with experience and knowledge, take (much easier) creative control of things like;

shutter speed
iso
aperture (= DoF)
focus distance (and object focussed on)
focal length = optical zoom

and all this over much greater ranges than might be possible on some phone cameras.

Hope that helps,

[ajohnw]

Thanks guys. Would anyone be able to tell me the technical differences between my photo and the photos I found on flickr? I don't expect to be able to achieve any of this on an iphone, just using it as a reference for a low quality photo.

I had a quick go at modifying the jpg to show you a couple of things but iPhone jpg quality is just not good enough so just a couple of points.

You'll notice that in most of the shots you linked to that the background contrasts the faces or head scarf to a certain extent. Pale face, pale hair, pale background can be a bad mix. Contrast is removed before the shot is even taken.

Blurring backgrounds can be good but it's often best to be subtle. The best way of getting a grip on that is to look directly at something and notice what happens with peripheral vision. It's all still there what ever it is but indistinct more so than it's possible to achieve with photo. A little blur on close backgrounds goes a long way. More distant backgrounds are more difficult but shape needs to be still just recognisable. Say it was a hedge. The leaves need to be recognisable as leaves - just. Blotches of contrasting colours are not a good idea at all in this situation. Black and white makes that aspect a lot easier.

Very slight not easily noticeable vignetting can have the same sort of effect as background blur. The 2 can be mixed together.

Facial features and their grittyness, softness, hardness etc is all down to contrast, saturation, colouration, vividness and similar variables. There may be some of these settings in your phone. Play around with them to see what they do. Lighting comes into it as well but needs some care for what might be called standard portraits. It's easy to leave nose shadows and things like that which don't do the image any good at all on the other hand flat even lighting tends to give flat results.

Your question - dynamic range doesn't have any effect on mid tones at all only on the extent of the dynamic range. Mid tones are mid tones and that's it. Even a phone is likely to capture what are generally regarded as mid tones fairly well. Where higher dynamic range cameras score is the ability to capture more of the range outside of these more correctly and to a greater extent.

John
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