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dark_lord’s latest blog : presentation styles

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Presentation Styles

25 Nov 2021 7:54PM  
Views : 96
Unique : 90

This is a related topic to my previous blog concerning image style. How we present our images has an effect on how they’re perceived.

The vast majority of images are viewed online these days, or at least on an electronic device. The way images are presented on screen and in print can be very different. Some ways work just as well, others suit one or the other medium better. Better is a subjective term of course, it’s that some ways are more effective than others. So I’ll look at some examples with some general guidance.

Let’s first consider online images. Most are displayed on a web page as is. Often this is fine, and for general sites where images are purely informational you don’t need any more. For photographic sites, and sites where the image is important it can help if the image is demarcated in some way. Many poto sites have black or dark grey backgrounds. That in itself is a presentation style and with good reason, as the images, especially colour, appear more vibrant that way. Strongly coloured or darker images need something to contain or define the extremities and a thin keyline does help. Equally with pale or high key images on a white background.

The question then becomes how wide a keyline to use. Thin lines are often sufficient. Black or white keylines often work best as they don’t fight the image for attention. There is a school of thought that says avoid coloured lines. But they are worth a try, for example a sepia line around a sepia toned image may be less stark than black or white. Bright colours work less well, or rather suit fewer subjects. But don’t feel constrained. Simple keylines look good on printed images.

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The next step is a border. They can be used for effect, to simulate the white border you used to get on prints years ago. Given that screen area is an issue, borders can make the displayed image small and thus lss engaging for the viewer. Great if you have a 4K screen but phone and tablet viewers will be at a disadvantage. With print there’s more freedom to choose, though as a viewer I’m not a fan of small images floating in a sea of white as I feel cheated that I cant enjoy the image to it’s fullest extent. Certainly with prints though, some border, whether that’s space on the print itself or the use of a mount, can set the image off in a frame. Mount colour is important, and generally pale neutral tones suit most images. Darker mounts can complement an image, for example dark green surrounding a woodland image though the important thing is that it’s complementary. If you have a bright subject you may want to try a bright mount, but I’d say it’s much harder work. Or maybe you prefer he image going right up to the frame edges?

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There was a trend when digital photography first became popular for wacky borders, from multiple lines to ornate frames. Multiple lines are a big distraction, and just because it’s possible doesn’t mean it should be used. It could work on occasion, for example a stark graphic mono image with several alternating black and white mini borders, but it’s so much the exception. Over the top borders so draw attention from the image.

18034_1637869795.jpg

Talking of frames, why use an ornate classical looking gold frame for online images? I can understand that if you’re selling frames or framed prints and need to show them in context. I’m not saying don’t use one but for online viewing a cleaner look is better appreciated, and again remember you’ve limited screen space.

Photobooks are yet another area and really deserve to be treated separately as you’re into numerous layout options. Suffice to say that they are smaller in format so you have similar issues to screen size.

The important thing to remember is that it should be the image that takes centre stage and keeping presentation simple is the most effective way.

All text and images © Keith Rowley 2021

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dark_lord’s latest blog : style, what’s yours?

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Style, What’s Yours?

17 Nov 2021 5:31PM  
Views : 8
Unique : 7

Many photographers produce images that are recognisably theirs. Thankfully there’s no formula for style, it’s down to our individuality, but there are various aspects that combine to create a style

Style, in terms of the appearance of an image, is something we all have. It’s our visual signature, and just like written signatures some are easy to read and recognise here are those that are nondescript. Some photographers may have style too, but generally their fashion sense isn’t to be noted, so that’s best left for their subjects in front of the camera. I’ll restrict my discussion to image style and ignore presentation and working styles which are subjects in their own right.

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How to define what style is is not easy, but there are some image attributes that can be considered as part of style. Composition is an important part of photography and the way it’s used by different people can vary enormously even of the same subject. For example bold tight framing or extreme placement of a subject in the frame. The use of a particular lens can become recognisable, such as very wideangle lenses especially for subjects you wouldn’t normally expect them to be used for. Lighting set-ups add another dimension. Post processing can have a big impact on style, so there are innumerable possibilities but examples could include highly saturated or delicate pastel tones, split toned or very lightly toned mono. Subject type isn’t really part of style but some photographers concentrate on certain types of subject and combined with the other attributes mentioned all add up to individuality. A decade or so ago having very heavily processed dark skies on landscapes was popular. Yes that’s a trend but some people it became part of their style.

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Do you consciously develop a style or does it just evolve as your photography progresses? For many people it’s the latter as our experiences and influences affect the way we see the world. Sure, some may have a desire to produce particular looks. That’s just choosing an element or two that become part of their overall style as a result. Looking through the ephotozine gallery there are thumbnails that stand out that you know are by certain people. Then there are those who have different styles for their colour and mono work.

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Does style pigeon-hole you? I guess no more so than being a subject specialist. Style will change over time as experience,trends and techniques alter. That’s only natural. By how much and how quickly, that’s the big variable. If fashions and trends change your style may fall foul of them, but that’s only important if you market your stylised work. On second thoughts, in this age of social media having a popular style may be a significant factor for those that crave ‘likes’. If you only produce work to please yourself, then carry on.

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Do you, or should you emulate or try to copy someone else’s style? In one sense it can be seen as fraud because you could be trying to pass off an image that. There’s no reason you can’t take some aspect of someone’s style and try it for yourself, it’s part of the learning and creative process of photography. For example, high contrast black and white images. It’s not someone’s exclusive domain and many photographers use it. But in different ways. Then there’s the fact that by looking at images you admire, that all have one style or another, you will be influenced by those images so a certain amount of style will ub of on you as it were. The same can be said for food where flavours used in one cuisine can be used by chef;s in recipes from different parts of the world. As an example I’ll give you an Indian spice inspired haggis, a fusion of Asian and Scottish food (and very good it is too).

You may be able to describe our own style. Some may not give it any thought and just ‘do what they do’. Personally I think I’m too close to the wood to see the trees so that’s why I leave it to others.

All text and images © Keith Rowley 2021

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dark_lord’s latest blog : threshold

18034_1634850509.jpg

Threshold

21 Oct 2021 10:16PM  
Views : 333
Unique : 183

Threshold is one of those image adjustments that may at first seem at best odd and at worst perhaps pointless. There may be some other uses, but here’s what I’ve used it for.

I’m going back a couple of years to 2019 and some photos of Ben.M I took at one of John Duder’s lighting workshops. I must emphasise that the key part of making the image lies in the lighting. That gets you where you need to be. Don’t ignore or undervalue the importance of getting a good image in camera. The post processing just enhances the result to get to a point I’d envisaged.

18034_1634850509.jpg

The idea in this studio set-up was to light the background and have Ben appear in profile. It’s almost silhouette as there is some detail in the subject created by light bouncing off the background. Indeed, a little detail like this does help with shape and form. It is perfectly possible to reduce the Black level to get pure black with no detail if you want to. I could have done that, but I wanted something much simpler, I wanted a pure shape.

That’s where the Threshold adjustment comes in. It produces pure black and puire white tones, Something that isn’t quite so effective by adjusting the Black and White points using the Levels adjustments. Threshold has its own control so you can vary what becomes black or white, and there’s no grey. That said, I left mine at the default as that looked good and just shows hat if you get the lighting right to start with it makes adjustments in software so much easier and more pleasing to the eye.

18034_1634850518.jpg

My idea was to create a narrative of a saxophonist playing the blues, hence the colour. Perhaps not an original idea and I don’t always come up with fancy titles, its the image I’m interested in. To do this I created a new Fill Layer and set the blend mode to Colour. I was happy with the result, so left the opacity of that Fill Layer at 100%, Depending on your own preferences you may want a lower opacity for more subtlety. Experimenting with Blend Modes revealed other options like a blue figure on a white background and different complementary colours such as a yellow figure on a blue background. I guess those could make for a triptych or pop art arrangement.

18034_1634850525.jpg

I had to use a Fill Layer to get the colour because the Recolour adjustment, which I often use for sepia and other toning, won’t work with pure blacks and whites. However, as all the adjustments are made on separate layers it’s easy to switch them on and off and in doing so I found I liked the effect of the Recolour on the oriinl image as there were some mid-tones that the colour could work on. This turned ou to be my favourite version. If, in the future, I want a different colour, I won’t go tough the whole profess again as the Hue/Saturation adjustment will work just fine.

Threshold is useful for producing a solid silhouette useful on its own or in a composite as I did here with this image from Southport airshow taken a few years ago.

18034_1634850533.jpg

It’s worth crossing the threshold now and again.

All text and images © Keith Rowley 2021

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dark_lord’s latest blog : fingerprints on film

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Fingerprints on Film

29 Oct 2021 7:02PM  
Views : 322
Unique : 198

As a title that’s not as slick as the Duran Duran song (you’ll be hearing that all day now!) but it does describe one of the pitfalls of the analogue medium.

In the early 1990s I had a transparency that I took in to a high street processing lab in order to get a print made. It was a branch of Max Spielmann (that particular branch has long since gone). The assistant was very clumsy and when picking up the transparency picked it up without paying attention with finger and thumb right across the image area. Horror! I guess in hindsight I should have at least complained and walked out of the shop.

18034_1635530190.jpg

That’s when I decided not to use high street processing outlets. I’m not saying all their branches or indeed all high street outlets had the same laissez-faire approach, but situations like that certainly make you ask all sorts of questions about customer service and quality control.

My transparency film was mostly the process paid sort, that which wasn’t was sent off in the post to trusted labs (found in those days in the advertisements at the back of the photographic magazines). Peak Imaging was one such place, and I also used a local branch of Colab (since taken over by One Vision Imaging and the local site abandoned, a casualty of the march of digital). Of course, there’s always the risk of damage in transit but there’s no need to get paranoid. Given the amount of photo material I sent and recived through the mail I can remember only one occasion when something went missing, though it was retrieved with no adverse effects.

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Fortunately I can’t see any damage to the image yet and it hasn’t revealed itself in the scan. Acid from skin will in time eat away at photographic emulsions. That said, it’s quite amazing how some film and prints survive poor storage.

These days if I want a print from a negative or transparency I create a high quality digital file and upload that unless I print it myself. Time constraints and large sizes as well as special surfaces like acrylic mean home printing is out, otherwise home printing it is. Either way, creating a digital file means I can get the image just as I want it, for example colour balance, colour correction, contrast, shadow detail and so on.

Oh, and removal of fingerprints.

All text and images © Keith Rowley 2021

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dark_lord’s latest blog : what’s acceptable?

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What’s Acceptable?

3 Nov 2021 4:36PM  
Views : 330
Unique : 226

There’s no camera or lens that’s perfect, though some may come close. There’s always a compromise somewhere. I’ll look at a few areas of performance where you need to make that judgement call.

Le’s start with sensor noise at high ISO, it’s as good a place as any. In their infancy, digital cameras produced noisy images at ISO 400 and above. Bear in mind though, that as the film era had reached its pinnacle grain was evident in emulsions of ISO 400 and above. The latest Fujichrome 400 Professional had well controlled grain and much finer than older types. Grain, and noise, were accepted as part of the image whichever medium you shot. News pictures, often taken in less than ideal conditions necessitated high ISOs and grain and noise were part of the experience. Just think of some of the classic news shots of the past. Lets also not forget concert and sports photography in low available light venues. Back in the day there were those that wouldn’t touch ISO 400, so they missed out on photo opportunities.

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ISO 6400 with indoor action

Today, ISO 1600 is effectively noise free and indeed ISO 12800 is usable on many models. Sure, if you pixel peep you may see some and camera reviewers tend to do that, but in practice how much are you going to notice between the different models and brands. Even cameras from a few years ago aren’t that bad, certainly when put in perspective. Careful use of noise reduction software will make a big difference too. Even my EOS 5D3 isn’t bad at ISO 6400 even though it’s long in the tooth now. What is accepted as the norm changes quickly an our expectations do likewise, perhaps unfairly and with unnecessary dissatisfaction with results which in the main are still fine. You may hear the term ‘usable’ ISO. That’s rather misleading as they are all ‘useable’. What’s really meant is that some don’t like to see very noisy images, but for some in the photojournalism world they take as high an ISO as they can get come wha may if that’s the only way to get the image.

18034_1635957095.jpg

ISO 12800 at a rehearsal in Tewkesbury cathedral

Diffraction, which was the subject of one of my recent blogs, causes softening of an image to varying extents dependent on aperture and lens design. How much it affects the image and how much it matters will be crucial to some and a small irritation to others. Indeed some may not even notice (or care) especially if the images is viewed small or downsized.

Converging verticals aren’t an issue with equipment per se. They are the result of viewpoint and camera angle. They can be used to effect, so care is needed with composition, but it’s the images where the convergence looks awkward that are less readily accepted. If they’re in the background the main subject should take centre stage so odd looking verticals may not be a concern. Then there’s how much ‘correction’ that’s needed in order to bring them into line with what our brain does automatically. It’s often that only 95% correction looks more ‘natural’ as we expect the top of a (tall) building to be smaller as we look up because we know it’s further away. Full ‘correction’ can make the building taper outwards and give the impression it’s larger at the top than at the bottom (though the Walkie-Talkie in London challenges that). Our brains find that hard to accept albeit geometrically more accurate.

18034_1635957106.jpg

A 100% crop with further noise reduction applied via Nik Dfine

Lenses are not perfect. It’s true that there are some very good ones. These ‘imperfections’, even ‘defects’ are seen by some as ‘character’. Chromatic aberration, barrel and pincushion distortion can all be rectified in software. Others, such as poor edge softness at wide apertures can’t be resolved (no pun intended) and have to be endured, but depending on the nature of the image (for example a central subject) or the need to get a shot (as in newsworthy reporting) this may well be of less significance. Then there are those that take it to the extreme and use Lensbabies purely because of these properties. Go figure (again no pun intended but for figure studies they can yield appealing results).

How much or how little these concern individual photographers will vary widely, that should go without saying, it’s up to us to determine our individual acceptance level. Keeping things in perspective and being aware of differences will definitely help.

I’ve only discussed some of the physical properties that affect images. What’s acceptable aesthetically, and ethically for that matter too, are different ball games.

]All text and images © Keith Rowley 2021

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dark_lord’s latest blog : what’s acceptable?

18034_1635957170.jpg

What’s Acceptable?

3 Nov 2021 4:36PM  
Views : 38
Unique : 34

There’s no camera or lens that’s perfect, though some may come close. There’s always a compromise somewhere. I’ll look at a few areas of performance where you need to make that judgement call.

Le’s start with sensor noise at high ISO, it’s as good a place as any. In their infancy, digital cameras produced noisy images at ISO 400 and above. Bear in mind though, that as the film era had reached its pinnacle grain was evident in emulsions of ISO 400 and above. The latest Fujichrome 400 Professional had well controlled grain and much finer than older types. Grain, and noise, were accepted as part of the image whichever medium you shot. News pictures, often taken in less than ideal conditions necessitated high ISOs and grain and noise were part of the experience. Just think of some of the classic news shots of the past. Lets also not forget concert and sports photography in low available light venues. Back in the day there were those that wouldn’t touch ISO 400, so they missed out on photo opportunities.

18034_1635957170.jpg

ISO 6400 with indoor action

Today, ISO 1600 is effectively noise free and indeed ISO 12800 is usable on many models. Sure, if you pixel peep you may see some and camera reviewers tend to do that, but in practice how much are you going to notice between the different models and brands. Even cameras from a few years ago aren’t that bad, certainly when put in perspective. Careful use of noise reduction software will make a big difference too. Even my EOS 5D3 isn’t bad at ISO 6400 even though it’s long in the tooth now. What is accepted as the norm changes quickly an our expectations do likewise, perhaps unfairly and with unnecessary dissatisfaction with results which in the main are still fine. You may hear the term ‘usable’ ISO. That’s rather misleading as they are all ‘useable’. What’s really meant is that some don’t like to see very noisy images, but for some in the photojournalism world they take as high an ISO as they can get come wha may if that’s the only way to get the image.

18034_1635957095.jpg

ISO 12800 at a rehearsal in Tewkesbury cathedral

Diffraction, which was the subject of one of my recent blogs, causes softening of an image to varying extents dependent on aperture and lens design. How much it affects the image and how much it matters will be crucial to some and a small irritation to others. Indeed some may not even notice (or care) especially if the images is viewed small or downsized.

Converging verticals aren’t an issue with equipment per se. They are the result of viewpoint and camera angle. They can be used to effect, so care is needed with composition, but it’s the images where the convergence looks awkward that are less readily accepted. If they’re in the background the main subject should take centre stage so odd looking verticals may not be a concern. Then there’s how much ‘correction’ that’s needed in order to bring them into line with what our brain does automatically. It’s often that only 95% correction looks more ‘natural’ as we expect the top of a (tall) building to be smaller as we look up because we know it’s further away. Full ‘correction’ can make the building taper outwards and give the impression it’s larger at the top than at the bottom (though the Walkie-Talkie in London challenges that). Our brains find that hard to accept albeit geometrically more accurate.

18034_1635957106.jpg

A 100% crop with further noise reduction applied via Nik Dfine

Lenses are not perfect. It’s true that there are some very good ones. These ‘imperfections’, even ‘defects’ are seen by some as ‘character’. Chromatic aberration, barrel and pincushion distortion can all be rectified in software. Others, such as poor edge softness at wide apertures can’t be resolved (no pun intended) and have to be endured, but depending on the nature of the image (for example a central subject) or the need to get a shot (as in newsworthy reporting) this may well be of less significance. Then there are those that take it to the extreme and use Lensbabies purely because of these properties. Go figure (again no pun intended but for figure studies they can yield appealing results).

How much or how little these concern individual photographers will vary widely, that should go without saying, it’s up to us to determine our individual acceptance level. Keeping things in perspective and being aware of differences will definitely help.

I’ve only discussed some of the physical properties that affect images. What’s acceptable aesthetically, and ethically for that matter too, are different ball games.

]All text and images © Keith Rowley 2021

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dark_lord’s latest blog : fingerprints on film

18034_1635530190.jpg

Fingerprints on Film

29 Oct 2021 7:02PM  
Views : 42
Unique : 36

As a title that’s not as slick as the Duran Duran song (you’ll be hearing that all day now!) but it does describe one of the pitfalls of the analogue medium.

In the early 1990s I had a transparency that I took in to a high street processing lab in order to get a print made. It was a branch of Max Spielmann (that particular branch has long since gone). The assistant was very clumsy and when picking up the transparency picked it up without paying attention with finger and thumb right across the image area. Horror! I guess in hindsight I should have at least complained and walked out of the shop.

18034_1635530190.jpg

That’s when I decided not to use high street processing outlets. I’m not saying all their branches or indeed all high street outlets had the same laissez-faire approach, but situations like that certainly make you ask all sorts of questions about customer service and quality control.

My transparency film was mostly the process paid sort, that which wasn’t was sent off in the post to trusted labs (found in those days in the advertisements at the back of the photographic magazines). Peak Imaging was one such place, and I also used a local branch of Colab (since taken over by One Vision Imaging and the local site abandoned, a casualty of the march of digital). Of course, there’s always the risk of damage in transit but there’s no need to get paranoid. Given the amount of photo material I sent and recived through the mail I can remember only one occasion when something went missing, though it was retrieved with no adverse effects.

18034_1635530201.jpg

Fortunately I can’t see any damage to the image yet and it hasn’t revealed itself in the scan. Acid from skin will in time eat away at photographic emulsions. That said, it’s quite amazing how some film and prints survive poor storage.

These days if I want a print from a negative or transparency I create a high quality digital file and upload that unless I print it myself. Time constraints and large sizes as well as special surfaces like acrylic mean home printing is out, otherwise home printing it is. Either way, creating a digital file means I can get the image just as I want it, for example colour balance, colour correction, contrast, shadow detail and so on.

Oh, and removal of fingerprints.

All text and images © Keith Rowley 2021

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dark_lord’s latest blog : threshold

18034_1634850509.jpg

Threshold

21 Oct 2021 10:16PM  
Views : 30
Unique : 28

Threshold is one of those image adjustments that may at first seem at best odd and at worst perhaps pointless. There may be some other uses, but here’s what I’ve used it for.

I’m going back a couple of years to 2019 and some photos of Ben.M I took at one of John Duder’s lighting workshops. I must emphasise that the key part of making the image lies in the lighting. That gets you where you need to be. Don’t ignore or undervalue the importance of getting a good image in camera. The post processing just enhances the result to get to a point I’d envisaged.

18034_1634850509.jpg

The idea in this studio set-up was to light the background and have Ben appear in profile. It’s almost silhouette as there is some detail in the subject created by light bouncing off the background. Indeed, a little detail like this does help with shape and form. It is perfectly possible to reduce the Black level to get pure black with no detail if you want to. I could have done that, but I wanted something much simpler, I wanted a pure shape.

That’s where the Threshold adjustment comes in. It produces pure black and puire white tones, Something that isn’t quite so effective by adjusting the Black and White points using the Levels adjustments. Threshold has its own control so you can vary what becomes black or white, and there’s no grey. That said, I left mine at the default as that looked good and just shows hat if you get the lighting right to start with it makes adjustments in software so much easier and more pleasing to the eye.

18034_1634850518.jpg

My idea was to create a narrative of a saxophonist playing the blues, hence the colour. Perhaps not an original idea and I don’t always come up with fancy titles, its the image I’m interested in. To do this I created a new Fill Layer and set the blend mode to Colour. I was happy with the result, so left the opacity of that Fill Layer at 100%, Depending on your own preferences you may want a lower opacity for more subtlety. Experimenting with Blend Modes revealed other options like a blue figure on a white background and different complementary colours such as a yellow figure on a blue background. I guess those could make for a triptych or pop art arrangement.

18034_1634850525.jpg

I had to use a Fill Layer to get the colour because the Recolour adjustment, which I often use for sepia and other toning, won’t work with pure blacks and whites. However, as all the adjustments are made on separate layers it’s easy to switch them on and off and in doing so I found I liked the effect of the Recolour on the oriinl image as there were some mid-tones that the colour could work on. This turned ou to be my favourite version. If, in the future, I want a different colour, I won’t go tough the whole profess again as the Hue/Saturation adjustment will work just fine.

Threshold is useful for producing a solid silhouette useful on its own or in a composite as I did here with this image from Southport airshow taken a few years ago.

18034_1634850533.jpg

It’s worth crossing the threshold now and again.

All text and images © Keith Rowley 2021

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dark_lord’s latest blog : diffraction ? the enemy of sharpness

18034_1633984326.jpg

Diffraction – the Enemy of Sharpness

11 Oct 2021 9:41PM  
Views : 83
Unique : 74

Using small apertures is good for obtaining large depth of field, but go too small and image quality worsens. How bad is the effect and is it worth being concerned about?

Let’s take a look at what diffraction is. I recall physics experiments at school creating waves in a water tank passing through various sized slits in a metal barrier and observing the patterns produced. The waves spread out from the slit, more so the smaller the slit. The observation applies to water waves, sound waves and electromagnetic radiation. It’s this spreading that causes the softening in an image.

During my experiments with depth of field, looking closely, that is at 100% on screen, there is a noticeable softness at smaller apertures. It’s not a lot, and it depends on how large you’re going to print an image and how far away are you going to view it. With higher resolution sensors this softening will be more apparent if you look closely enough. The result may just give the impression that you’ve shot on a lower resolution camera, and for web size images or small prints may well not be a concern for some.

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The full image at f/32 as displayed on the web looks fine.

The effect is much more noticeable when I use an extender and extension tube on the macro lens below f/11, but then the lens was never designed for that extreme use. I’ve found apertures down to f/11 are fine, and as depth of field is so minimal at such close quarters I’ll forego that fraction of a millimetre for better overall sharpness.

18034_1633984386.jpg

I used my macro lens for these images which is designed to hold up well at these smaller apertures. I have to say I’ve very rarely gone below f/16 in normal use or noticed anything untoward on earlier lower resolution sensors. That said, all lenses are different so you need to do your own tests. Zooms, particularly at the cheaper end of the market, are much more likely to suffer image quality reduction at the small apertures. I have come across images online that even at that reduced size (from the original capture) do show a marked softness, while at the same time ruling out as far as possible camera rigidity and ISO effects.

18034_1633984441.jpg

Look closely and the detail isn’t as crisp as it is at f/8, but are you going to look this close?

Small apertures and diffraction effects are the reason you won’t find apertures below f/8 on small sensor cameras, and indeed f/8 will, on those cameras, give as much depth of field as you’re likely to need.

Are there good things about diffraction? When you’re down to X-ray wavelengths diffraction patterns are created by the arrangements of atoms which allow molecular structures to be determined. That’s important in areas such as novel drug development. So some diffraction is not all bad.

All text and images © Keith Rowley 2021

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dark_lord’s latest blog : differential focus

18034_1633465959.jpg

Differential Focus

5 Oct 2021 9:34PM  
Views : 40
Unique : 30

The effect is used to isolate a sharply focused subject against an out of focus background (or foreground).It’s a good reason to buy a wide aperture lens.

Following on from my experiments with depth of field, the natural extension to that is differential focus. What is it, why is it useful why it’s harder to achieve with smaller format sensors and phones than larger formats such as full frame and medium format, and easier with wide aperture lenses than kit lenses.

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]

So you may think you don’t need a wide aperture lens what with the good to excellent high ISO performance of sensors these days. That’s a fair point, and with a lot of photography done using mid to smaller apertures the point of using f/2.8 or wider may be questionable. The size and price may be off-putting factors too as wide aperture lenses tend not to be a bank balance’s best friend.

Smaller maximum aperture lenses (such as kit zooms that are f/5.6 wide open at the long end) are also less of an issue with mirrorless cameras where the viewfinder compensates for the less amount flight entering the camera. Conventional systems in DSLRs do go darker – not massively so but some may find difficulty. If shutter speeds become slow, then where you have image stabilisation in the lens and/or camera body you may feel safe. There is a caveat ad it’s in the name of the feature – it’s just the image that’s stabilised, not the subject. There are creative opportunities there of course, but it’s sometimes hard to explain to a novice that although they’ve got a perfectly hand-holdable set-up at 1/15 s their subject is blurred beyond reasonable recognition. Wider apertures will let you go on shooting as conditions get more challenging.

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That’s it from a practical point of view. As a creative tool though, if wide apertures give the effect you want then you need to get one of these lenses. Software manipulation doesn’t come close, I’m afraid. You do need to be accurate with your focus, as there’s little or no room for error. An image that isn’t focussed strongly on the main subject just fails.

Forget the maths, experience shows it boils down to the size (diameter) of the glass, so I you don’t have an 85 f/1.2 then a 200 mm lens at f/2.8 would do (the diameter is similar). But for an even stronger effect try a 300 mm f/2.8 for portraits (the diameter is half as big again). Unconventional but give it a go.

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Differential focus is used for creative effect in TV and cinema. Indeed, some sequences have been shot on cameras like the Canon 5D Mk III purely to make use of the effect. That’s why it’s useful to use full frame cameras for video.

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There are many more exciting fast aperture lenses being produced for mirrorless systems, which is good to see. It’s true they can be expensive though some of the manual focus options are more wallet friendly. There is some good news hoverer, and that’s because of the plethora of adaptors available that many older lenses can be used. Get in there now for a bargain before everyone susses this one.

All text and images © Keith Rowley 2021

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