perfect reproductions
[0r WHY USE A SPECIALIST PHOTOGRAPHIC STUDIO
TO reproduce your art?]
- Securing Your Artwork
- Lighting the Artwork with North Light's HID Copy Lights
- Positioning the Camera
- Parallelism Adjustments
- Pre-Scanning to Adjust Size, Colour, Tonal Range and Focus
- The Final Scan
- Technical Summary from Better Light
- About Image Capture Using: 35mm Cameras | Flatbed Scanners
Achieving the Perfect Reproduction
The Reproduction of Fine Art using a Better Light Scanning Back on a 4x5 large format view camera is the very best option for creating editions from your original art work, as used in many of the worlds' top museums, including our own Royal Victoria Museum, BC. Here we've provided a detailed, illustrated step-by-step guide to our 'image capture' process to illustrate the difference that you can expect using a specialized photographic studio. In the words of Mike Collette, founder and CEO of Better Light:"Beware of anything less than the best!"
1) Securing Your Artwork
The back wall of the studio is covered with a sheet of steel, painted black. The artwork is secured flat against the steel using specially designed, very powerful plastic coated magnetic clamps. They are versatile enough to work with paper, loose fabric, a stretched canvas, a wooden panel, in fact any flat media almost regardless of it's depth or weight.
The back wall of the studio is covered with a sheet of steel, painted black. The artwork is secured flat against the steel using specially designed, very powerful plastic coated magnetic clamps. They are versatile enough to work with paper, loose fabric, a stretched canvas, a wooden panel, in fact any flat media almost regardless of it's depth or weight.
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Left: The canvas stretcher frame is 'rested' on the inside of the Magnetic Clamps, which are pushed in firmly around the outside of the frame to collectively clamp the frame firmly flat against the wall...
Right: Magnetic Clamps hold artworks on paper firmly flat against the black sheet of steel mounted on the wall... |
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On the rare occasion that the artwork exceeds the capabilities of the clamps alone, extra support is provided underneath with wooden blocks. The system works so well that there is no chance of the artwork falling and being damaged and of course the clamps will not mark or dent your art. The surface of the art is then carefully dusted off with a large soft brush
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2) Lighting the Artwork with North Light's HID Copy Lights
For years lighting works of art with continuous light has presented problems in light levels, even illumination, heat from tungsten and HMI lamps, excess UV and IR levels, and power consumption. North Light Products, Inc., has worked closely with Better Light to produce a series of High-Intensity Ceramic Discharge Lamps specifically designed for art reproduction with digital scanning backs, solving most of the lighting issues of art reproduction. The color rendering index (CRI) is excellent with a 92-96 rating for the 4200K lamp. The lights provide more light intensity (lumens per watt; nearly 4 times that of tungsten lamps) and a very even light distribution without high infrared heat emission and minimal ultraviolet levels to satisfy museum standards. Each light unit is double fan-cooled (lamp side and electronics side of housing), so what all this means is that your artwork doesn't get heated or damaged by the lights during the scanning process |
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We use two of the largest model which at 900 watts each flood the artwork with soft even light, eliminating shadows created by unwanted texture. So what about specular reflection from glossy, varnished paintings with uneven surfaces? To eliminate that we double polarize: A large sheet of linear polarizing film is placed over each light and a linear polarizing filter, at right angles to those on the lights, is placed in-front of the camera lens. This eliminates all specular reflection, revealing the true colour of the paint behind the reflections. Although it quadruples the scanning time to around 20 - 25 minutes we don't charge any extra for this (all part of the service) but it's great if you can bring us your paintings before they are varnished!
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3) Positioning the Camera: The tripod with camera mounted is moved backwards and forwards along a line exactly at a right-angle to the centre of the back wall until the artwork fills the viewing area on the ground glass screen, ensuring maximum image capture size. Rough focusing is necessary throughout this process. Once this is done the fine tuning can begin...
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4) Parallelism Adjustments
For maximum sharpness of an image made with a camera, the lens and the digital sensor (or film) planes should be exactly parallel to each other; and then the both must also be perfectly parallel to the artwork. All view cameras have mechanical variations in the accuracy of their "zero" centering positions for swing and tilt movements and these tiny variations can cause a noticeable lack of focus precision from corner to corner. Better Light's extremely high-resolution imaging produces exceptional photographs, but also can be unforgiving, dramatically showing any error in overall focus or corner-to-corner sharpness. To avoid these errors a ZigAlign Rapid Alignment Mirror and Plate Set is used for checking parallel alignment of the artwork, the lens plane and the digital sensor plane. The View Camera Parallelism Plate (a) is used in the spring back of the rear standard (illustrated on the right), and the Ring Module (b), mounted on camera lens board, is placed on the front standard (in place of the lens) for alignment of the camera standards. The Camera Plate is designed and manufactured to duplicate the weight and balance of the Better Light scanning back to assure optimal accuracy.
Misaligned: When viewing through the small hole in the ring module, we see a series of concentric rings. In the example to the left the alignment is not correct. This same pattern is evident when aligning the front and rear camera standards, or if you are aligning the camera to the artwork.
Zig-Aligned: The goal is to see the series of concentric circles centered as shown in the photo to the right. When aligning the camera standards, the swing and tilt adjustments are used to make small changes in position until the circles line up |
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Once the camera elements are parallel the camera itself must be aligned to be parallel to the artwork: The mirror (c) is hung flat against the surface of the artwork, making sure that it is positioned so that it exactly reflects the circular mirror that faces it on the Parallelism Plate (a). By peering through the hole from the back (as seen above), which is in the centre of the mirror at the front, the same pattern of concentric circles will be observed as before, then the camera body position is adjusted via the tripod until exact alignment is achieved (Zig-Aligned) without any further alterations to the camera elements.
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5) Pre-Scanning to Adjust Size, Colour, Tonal Range and Focus
The ViewFinder™ camera control software delivers an unprecedented level of control over every aspect of image capture. After setting up the camera, lights and focus, the Better Light scan back is placed in the back of the camera and a low resolution prescan is made, then the preview image is displayed on the computer monitor. All exposure, sensitivity (ISO), color balance, and contrast/brightness adjustments will immediately update on the monitor, without the need for additional prescans. The software also fine-tunes the focus to an exacting degree beyond what is possible using a loupe on the ground glass screen. Better Light allows us to optimize conditions before image capture to assure the ultimate in first generation image quality. |
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6) The Final Scan
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Once satisfied with the prescan, the scan is started and the operator leaves the room because the scanning back is very sensitive to vibrations which will be rendered as jagged lines.
The scanning back and the laptop computer are linked by the integrated Better Light hard-drive where the images are stored. Once the scan is finished it is immediately opened on the laptop in Photoshop to check for sharpness and provided it's A-OK it is then downloaded from the Better Light hard-drive onto the more powerful production computer for "pre-press" work, complete with it's embedded colour profile. |
TECHNICAL SUMMARY FROM BETTER LIGHT
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For art reproduction….THERE IS NO BETTER CHOICE. The Better Light backs provide extremely sharp focus, wide dynamic range, total control of your image tone range, extraordinary adjustment of density (exposure) in less than 1/10th f-stop steps.
The technology used by Better Light is totally different from the single-shot digital capture cameras using area array sensors (CCD and CMOS). Our scan backs gather the information for the image in one continuous scan as the light is collected by three, individually filtered rows of pixels – this is called a tri-linear CCD. Since it moves across the “film plane” capturing light one row of pixels at a time, it will take several minutes to complete a large file. On the other hand, no other camera is gathering such a huge population of pixels (often 144 Megapixels or MORE) over such a large format area of nearly 3”x4”—that’s 5X the physical area of most array sensors! And, all of the pixels are PURE, true RGB color, not interpolated color by the camera software. The benefits are significant: Huge file size; pure pixel color; normal 4x5 view camera operation and lenses; adjustable resolution (file size) independent of the ISO range to as high as 3200; plus the award-winning software and tremendous customer support – putting Better Light into a totally unique class of digital backs. If you are using the scan back for product work, you will not have the moiré issues and noise problems that most of the other digital cameras experience. Your Better Light scanning back adds the benefits of true, large-format digital capture – without compromise.
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Super 6K-HS™ - Native maximum resolution at 100% = 6000 x 8000 pixels. 9000 x 12000 pixels - Enhanced Resolution™. Maximum file size at 150% = 309 MB in 24-bit RGB (618 MB 48-bit)
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about image capture using 35MM cameras & flatbed scanners
35mm Cameras
Have you have ever tried to photograph your art yourself or contracted a professional photographer using 35mm equipment to photograph it for you, only to find out that the images won't enlarge to the size you were hoping for without an unacceptable lack of sharpness and resolution? Art reproduction is very specialised process not fully understood by most professional photographers who doubtless believe, if they haven't tried it before, that it will be just another assignment.
However, if this is your only or best option, it's going to help if the photographer has some experience in the photography of fine art for reproduction, and if so they should be able to provide us with a correctly exposed colour chart plus the inclusion of a grey scale or 18% gray card within the image area, which will greatly enhance our ability to achieve correct color matching. If possible we encourage you to put us in touch with your photographer prior to the shoot to give us the opportunity to discuss these and many other technical issues. Digital image files should be saved as Tiffs with the correct ICC colour space for maximum colour gamut, Adobe RGB. For more on the subject please read my Blog Post "Photographing Your Artwork with a 35mm Camera: A Few Basic Guidelines."
35mm digital images will usually require at least some enhancement in PhotoShop (usually up to an hour's work) to achieve a presentable fine art print up to about 36"x 24". This skilled work involves, for example, the the separation/lifting of shadow tones, removal of digital fringing, the elimination of colour noise and pixelation and sharpening the fine detail. (Read more about image optimization.) Whilst the final image cannot be compared to those achieved with our Better Light Scanning Back, our many clients who have taken this route have always been delighted with the results.
Have you have ever tried to photograph your art yourself or contracted a professional photographer using 35mm equipment to photograph it for you, only to find out that the images won't enlarge to the size you were hoping for without an unacceptable lack of sharpness and resolution? Art reproduction is very specialised process not fully understood by most professional photographers who doubtless believe, if they haven't tried it before, that it will be just another assignment.
However, if this is your only or best option, it's going to help if the photographer has some experience in the photography of fine art for reproduction, and if so they should be able to provide us with a correctly exposed colour chart plus the inclusion of a grey scale or 18% gray card within the image area, which will greatly enhance our ability to achieve correct color matching. If possible we encourage you to put us in touch with your photographer prior to the shoot to give us the opportunity to discuss these and many other technical issues. Digital image files should be saved as Tiffs with the correct ICC colour space for maximum colour gamut, Adobe RGB. For more on the subject please read my Blog Post "Photographing Your Artwork with a 35mm Camera: A Few Basic Guidelines."
35mm digital images will usually require at least some enhancement in PhotoShop (usually up to an hour's work) to achieve a presentable fine art print up to about 36"x 24". This skilled work involves, for example, the the separation/lifting of shadow tones, removal of digital fringing, the elimination of colour noise and pixelation and sharpening the fine detail. (Read more about image optimization.) Whilst the final image cannot be compared to those achieved with our Better Light Scanning Back, our many clients who have taken this route have always been delighted with the results.
Flatbed Scanners
These will provide sufficient file size and resolution, so if you already have scans made this way we should be able to work with them. However, if you are considering having your art scanned this way it is worth taking into account that there are flaws inherent in their design that can render a less than perfect result:
1) The available surface area of the scanner limits the size of the artwork that can be scanned in one pass. If the artwork is larger than the scanner it has to be scanned in sections which then have to be "stitched" together on the computer with software such as PhotoShop. All this adds up to extra time and therefore cost which will be passed onto the client.
2) A scanner uses a narrow strip lamp that creates harsh shadows from the surface texture of the watercolour paper or canvas because the light source is not at 90 degrees to the print, typically around. 45 degrees. Known as the grazing angle of the flatbed's light source, it varies with different models, but this non 90 degree lighting makes any texture really jump out. The 'orange peel' surface texture of the photographic paper from school and wedding photo shoots appear as many "moon craters" when greatly magnified. Imagine how much this effect is exaggerated when scanning watercolour paper or thick oil/acrylic paint on canvas - any colour in the shadows cast by the peaks is lost and will print as black.
3) It gets worse if the painting is varnished because the glossy surface will reflect the light back when the it hits at certain angles (specular reflection) and print as white, again losing the original colour. When you print the resulting image file onto textured paper or canvas you get an 'image of texture' on top of the 'true texture' of the print media, which is undesirable and unprofessional.
4) Flatbed scanners can damage your artwork, especially if it is an oil or acrylic painting. The pressure can flatten or break the texture of the paint and there is the possibility of the paint sticking to the glass.
These will provide sufficient file size and resolution, so if you already have scans made this way we should be able to work with them. However, if you are considering having your art scanned this way it is worth taking into account that there are flaws inherent in their design that can render a less than perfect result:
1) The available surface area of the scanner limits the size of the artwork that can be scanned in one pass. If the artwork is larger than the scanner it has to be scanned in sections which then have to be "stitched" together on the computer with software such as PhotoShop. All this adds up to extra time and therefore cost which will be passed onto the client.
2) A scanner uses a narrow strip lamp that creates harsh shadows from the surface texture of the watercolour paper or canvas because the light source is not at 90 degrees to the print, typically around. 45 degrees. Known as the grazing angle of the flatbed's light source, it varies with different models, but this non 90 degree lighting makes any texture really jump out. The 'orange peel' surface texture of the photographic paper from school and wedding photo shoots appear as many "moon craters" when greatly magnified. Imagine how much this effect is exaggerated when scanning watercolour paper or thick oil/acrylic paint on canvas - any colour in the shadows cast by the peaks is lost and will print as black.
3) It gets worse if the painting is varnished because the glossy surface will reflect the light back when the it hits at certain angles (specular reflection) and print as white, again losing the original colour. When you print the resulting image file onto textured paper or canvas you get an 'image of texture' on top of the 'true texture' of the print media, which is undesirable and unprofessional.
4) Flatbed scanners can damage your artwork, especially if it is an oil or acrylic painting. The pressure can flatten or break the texture of the paint and there is the possibility of the paint sticking to the glass.
