January 7th, 2012
Intro: I’m in no way a self proclaimed expert in these matters and I do recognise that there are many ways to make pictures and systems to use that differ from the ones I’ve highlighted in this feature. However, I do produce prints with a high image quality and the processes that I use work for me. I do hope you can find them useful too.
Photographer: We often think of image quality as a technical thing but no amount of high end cameras lenses and equipment can make up for poor composition and lighting. No matter how sharp a picture is or how many pixels it has, the biggest factor in image quality will always be the photographer. The best way to improve an image is to improve the ability of the photographer.
Image: The photographer sees the potential photograph, the lens creates the image and the camera records the file. The photographer then processes that file and makes a print. Every stage of this process and the equipment used affects the resulting image quality. It’s like a chain that is only as strong as it’s weakest link.
Lighting: Contrast, direction, colour, quality, texture and tone are all properties of, or affected by, light. A well lit subject can look fabulous when photographed on a mobile phone, a poorly lit subject will look rubbish even if it is photographed on the latest medium format camera.
Lens quality: I’m not one to study MTF charts and lens statistics, I prefer to study real prints of normal subjects. I leave the optical analysis to the boffins. It comes as no surprise though that the more expensive a lens is, the better the image quality is likely to be. I’ve found this to be almost always true over the last twenty five years or so. One 50mm lens costing four times the price of another 50mm lens is not going to be four times as good. It will be better but not necessarily that much better, so there is certainly reason to choose your kit carefully. Generally speaking, buy the best lenses you can afford.
Zoom or Prime? I have recently once again made the switch from zoom lenses to prime lenses. I first did this when I bought my Hasselblad H2 and Phase One digital back in 2005. I used a set of four prime lenses to capture pictures with a fabulous image quality. I had 22 million pixels in a large sensor and the results were stunning. I then went back to zooms when I switched to Canon and I’ve finally ended up with 22 million pixels and prime lenses once more. I must say that my Canon 5Dmk2 coupled with prime lenses is every bit as good as my medium format kit was six years ago – such is the advancement in lens quality and image sensors. I noticed a big change when I recently switched from zooms to primes, mainly in the fine detail, contrast and clarity recorded. I lost the convenience of zooms but gained absolute sharpness. The latest generation of zooms are fabulous but I have found that they come into their own at f/4. I’ve spent many years shooting at f/4 and now that I’m on primes I find I’m getting similar or better resolution at f/2.8. I much prefer the f/2.8 look and now that I have startling clarity from my primes I’m happy to shoot at that aperture all the time.
Lens focus micro adjustment: No matter what lens you have it needs to be correctly paired with the camera body. I have set the focus micro adjustment for each of my three lenses using the custom menu in the camera. I put a steel tape measure on my table and align a pencil with the 1m mark on the tape. I mount the camera on a tripod and shoot a frame of the pencil at my regular aperture of f/2.8 from my usual working distance of 2 to 3 metres. I can then zoom in on the image to see if the camera has correctly focussed on the pencil. If not, I can check if it is back or front focussed by looking at the tape measure markings in the image. I then adjust the focus setting as required and confirm my results with a real test shoot. All my lenses have needed some adjustment and not in the same direction either.
Image stabilisation: This is a game changer for me. When I replaced my beloved 80-200 f/2.8 Nikon lens for the 70-200 f/2.8 VR (vibration reduction) my image quality from wedding shoots was instantly improved. It was not the optical resolution that made the difference. I tested the two lenses extensively and they were both acceptably sharp when used on a tripod. Modern IS or VR has about a four stop advantage and I find I can get acceptably sharp pictures from my 100mm macro L f/2.8 IS lens at just 1/15th of a second with the camera hand held.
Subject movement: IS or VR does not reduce subject movement and is no replacement for a large aperture when using long lenses to shoot moving subjects like people.
Tip: If in doubt slide all the switches away from you towards the front of the lens on a Canon IS or Nikon VR lens.
Camera stabilisation: For many subjects a tripod is a must, but for portraiture I prefer to work hand held or with a monopod. Being able to hold a camera steady is an absolute basic skill that needs practice and greatly affects image quality. When I’m not using IS or VR lenses over 50mm I nearly always use a monopod. I found that I could get acceptably sharp images at 1/30th second with my Hasselblad H2 and its non IS 210mm lens when I used a monopod and my subject was still.
Sensor size and sensitivity: This is a big one. As sensor size increases so does image quality, or so it should do, but there are other factors too. Sensitivity is one of them and it is a biggie for my kind of work. Medium format sensors tend not to have the sensitivity of sensors half their size or even smaller, and often deliver poor results at ISO1600 and above where my Fuji X100 excels. They do however have a high pixel count and a high surface area for the lens to focus onto.
Image processing: I’ve spent as many years working with film as I have with digital processing and I used to take a lot of care in producing good negatives to print from. The printing process was quite involved and every Lovegrove print was produced by hand. All our images had the benefit of burning and dodging and this gave our wedding albums a unique look. Most of our contemporaries in the days of film were using one of the many commercial labs machine printing services. I must admit I prefer a hand print from a film negative to a typically processed digital image. There’s a bit too much skin softening and sharpening in the majority of digital prints I see these days. It’s all personal taste but with digital files the damage can be permanent. My advice is if you are delivering pictures on disc give the client a set of straight processed files too. These will soon be far more valuable when realistic images are finally back in demand.
Computer screen: The single most important bit of kit for IQ in post production, apart from your eyes, is the computer screen. Ideally a screen should display all the colours in your chosen colour space. It should have a matte anti glare surface and a hood. Great screens displaying 97% – 100% of Adobe RGB can be bought for about £1000. A screen must be calibrated with a hardware device. The consequences of editing on a bad or uncalibrated screen are catastrophic. All the images will have errors that might not be repairable without starting from the original RAW file. Another obvious problem is that prints never look right or match the screen.
Eyes: Not everyone has perfect colour vision. It is worth having your eyes checked thoroughly (not just for a glasses prescription) if you are going to be editing pictures. In the days of film, labs did all the colour adjusting, nowadays it is left to the photographer or a dedicated editor. A good editor understands skin tones and should be able to ensure a consistent look throughout a body of work like a wedding album.
Wacom tablet: This device gives me the freedom to be light with my editing strokes. Ever since 1998 I’ve used a Wacom tablet to edit my images. It just works so well and the pressure sensitivity feature is amazing when using brushes.
RAW conversion: There are a handful of independent RAW processing packages like the renowned Capture One, plus there are the camera manufacturers’ own RAW processing packages that come bundled with their cameras. Users of these software packages are often fiercely loyal and claim to achieve a high image quality output. Lightroom and Aperture are still the front runners. I find Lightroom 3 more than adequate for my needs.
I do however have one little step in my workflow that has no impact on image quality but is worth mentioning. I use Photo Mechanic to quickly view, select and rename my raw files so that I only have to load a fraction of my images into Lightroom. Waiting for Lightroom previews to build or load is an annoyance in the otherwise smooth operation.
Once my shots are selected and renamed I trigger the Lightroom import process. This is one of the most important steps in achieving a super quality of image. I have taken the time to shoot a series of portraits at each ISO on both my cameras. I loaded the files into Lightroom and tweaked the noise reduction, adjusted the contrast, and set the desired camera profile and camera calibration to my taste for each image in turn and saved the default preset for each setting. I set the Lightroom preferences so that it automatically applies these settings for given camera serial number and ISO value at the import stage thereafter. I also set the blacks level to zero. Lightroom has the blacks set to 5 by default and this usually clips some useful shadow detail that I want to preserve. Now that this process is done I can enjoy understanding exactly how my images are going to look. It’s just like learning the look of a particular film/ developer combination.
Film is seeing a bit of a resurgence right now and having shot it for twenty years of my life I’m happy in the knowledge that digital capture done well can deliver more pleasing results without the hassle.
After the images have been adjusted in Lightroom they are exported as 16 bit tiffs in the Adobe RGB colour space for import into Photoshop. Once any final Photoshop adjustments have been made the files are saved as 8 bit tiffs and archived along with the selected camera RAW files. If no Photoshop work is needed they go straight to 8 bit tiffs. This is not the only system that works, far from it, but it does ensure that I get the image quality I demand in my prints.
I’m sure this post will raise many questions. I’m happy to let the conversation run as long as it stays on subject and relates to either these images, my techniques or image quality in general. Have your say. Join the debate. What do you want to add?