Friday 28 October 2011

Printing - Paper - Profiles

About a month ago I acquired an HP Z3200 24" printer and during the last few days it has undergone some intensive calibration and a host of test prints now adorn the walls.

The problems with printing are well understood but by way of a checklist and as an Aide-mémoire, this is my list, hopefully all checked and complete.

  1. A monitor that is calibrated.
  2. Ambient light levels to suit.
  3. Photo quality printer.
  4. Suitable paper.
  5. Paper profiles.
  6. Photoshop CSx
  7. Printing software. (Optional)
Some are obvious and some not quite so obvious, so I will look at them in more detail.

1. The calibrated monitor. My ASUS is  1900x1200 and does a good job but it will not calibrate properly. The calibration is by an Eye One Display 2 and it simply will not get rid of a red cast (best seen in a monochrome image, which should be entirely neutral) so, an Eizo CG241W is now used and the difference is considerable. The Eizo comes with its own calibration software and accepts the Eye One  device. The difference is that the Eizo is hardware calibrated, so therefore the vagaries of Windows, Video cards etc do not come into play. Item 1,
  
2. Ambient light levels. Not a huge problem but improved here by installing all lighting tubes that are daylight colour balanced, together with two desk lamps with daylight bulbs. Print evaluation under these conditions is therefore entirely neutral. Item 2,

3. Photo quality printer. The HP Z3200 is my choice. It uses 12 Vivera ink cartridges which include a gloss enhancer to eliminate bronzing and is the only printer at this size that makes its own icc profiles.
Item 3,
  
4. Suitable paper. This is more difficult to establish an absolute outcome. There are just so many to choose from and although it is possible to buy sample packs, they come in A4 size and only one of each type. Internet research establishes that other users have their preferences but this is such a subjective issue it is difficult to know. For now I am using HP roll paper and some sheet from Hahnemuhle and Harmon.

I will soon get some Canson as they seem to be well into HP printers and offer presets ready for profiling. Item 4, can do better

5. Paper profiles. The HP 3200 makes its own. Load some paper, two clicks later and about 30 minutes due to drying time and a bespoke .icc profile is loaded into the PC and a new Custom paper joins the list on the printer display. Apart from the correct calibration, platen distance etc the profile is essential for soft proofing. My wish list is that all paper looks the same when under soft proofing, but unfortunately that is not the case. Satin and Gloss types require less work under SP conditions. Matt goes very muddy (as it does with the profile for a Blurb book if you download their profiles) and is difficult to work with. There is work to do before the SP set up is truly correct. Under View > Proof Set Up > Custom a number of options need consideration. From the list in Device to Simulate pick up the profile of the paper. Rendering Intent is a area where there doesn't seem to be a whole amount of agreement or direction. Perceptual and Saturation seemingly produce similar results and I will choose Saturation in most instances. I keep Black Point Compensation ticked. Display options to Simulate Paper Colour and Black Ink will often horrify me as the bright screen image of the photograph now looks muddy again. The screen settings recommended by Eizo for photography are 100cd 6500k 2.20 and will always be brighter that the print. So, a few test prints are needed to establish what looks best but once recorded they will be good for 90% of printed output without any further. Save the Custom proof  with a name and date and use it as required. Control + Y toggles to the current settings.  Item 5,  with work ongoing to introduce Canson paper as soon as possible.

6. Photoshop CS5 for some post processing but I don't use it for printing.  

7. Printing software. My preferred method for output to the printer is via Qimage It is stand alone software and has a few features that are superior to the likes of CS5. The most notable is its ability to up size images from their native size with algorithms better than Bicubic found in CS5 and the output sharpening is automatically determined to suit the print size. Item 7.


Conclusion.

Digital printing to exhibition quality is nowhere as easy as in a wet darkroom, although the angst is at least consumed in daylight and without the smelly hands. Printing with an inkjet device requires research and patience, but when it all comes together the rewards are joyous.

P.S. Use white cotton gloves when handling paper rolls. The dreaded finger prints show up if not.

Monday 24 October 2011

Project 13 : the day

We all know that the sun rises in the East and sets in the West. Each day throughout the year where the sun rises and where it sets is slightly different and the height it rises to at midday varies as well. In there are only two days a year that are similar, March 21 and September 21. The longest day is June 21 and the shortest December 21.So at any particular day, as photographers we have to deal with our outside light source as variable and make the most of it,mainly by planning ahead.

In a recent post here I described some software that will calculate sunrise / sunset times and positions for any location on the planet.This may seem a bit over the top but for planning I think it is worth considering especially  if precise work is required, such as the sun rising behind a glass building or setting across a lake with a reflection. Another important note to take with you when out in mountainous areas is that the early and late sun will be hidden if you are in a valley that is aligned north south. Much better to be in an east west valley, where the early and late sun will be visible. The sunrise, sunset and twilight parts of the day are often referred to as The Golden Hour because of the nature of the light, its colour and the modelling effect it has on the features within the landscape. Long shadows, warmer tones are at their simplest more interesting than high bland mid day sun. Suffice to say that map reading, compass and watch skills are part of the landscape photographers kit if control is required rather than random stumbling onto the right situation.

The course notes ask us to spend a whole day at a location with some terrain and photograph the difference in light as it occurs. If one were to photograph a flat field during the day there would be no significant change, other than maybe the colour temperature being warmer in the morning and evening, with the midday light being blue maybe around 5600K. The purpose of the exercise is to notice and comment upon the changes we see during the day.

During a visit to The Lake District (well if I need contours and relief then here is about as good as it gets) I shot a simply sequence from 0500 through to 2000 of a fell side near the village of Threlkeld. I did not spend all day on this but did try and space out the shots and while maybe predictable the effects are noticeable, not only in shadow and shape, but also in the colour temperature. The photographs below are unprocessed images to allow full demonstration of the natural light and its colour.

 05:00 hrs
At 0500 hrs the shadows are long and the light is quite warm. The lit area to the left shows good detail due to the low angle of the sun and the warm light enriches the colour. The tree to the left is almost back lit and is partially silhouette. 

09:00 hrs 

At 0900 hrs light has become cooler and more uniform. The tree is now lit and provides more interest than before. The area of hill side to the left is now less interesting due to the sun being low and filling the shadows. The overall light is uniform and not that interesting.

14:00 hrs 

By 1400 hrs the sun is just past it highest point in the sky. The rocky area on the left hand side now has shadows due to it being on a slope of approximately 45 degrees and providing a good angle for the high light.

17:00 hrs 

At 1700hrs the sun provides oblique illuminate to the left hand side slope. The detail here with two distinct ridges is pronounced and has not been visible before.The tree becomes the dominant feature and the distant area in shadow less interesting.

  
20:00 hrs 

By late evening the sun has set and the entire area is in a flat light.
The light during the day had changed this somewhat unremarkable small vista pretty much as one would expect. The morning light (0500) in this instance gave the richer tone but suffered from the large shadow area and may have improved at around 0600 or slightly later. The 0500 image can be improved by some local adjustment.

05:00 with PP



Wednesday 19 October 2011

Project 35 : using a polarising filter

The course note for this project describe a number of situations where to try out the filter and the results to expect. Without doubt the main requirement is a bright sunny day with some blue sky.The science and detailed explanation of polarised light is perhaps not required although some understanding of whats going on will not go a miss. I resort here to Wikipedia as my source.

"Some of the light coming from the sky is polarized (bees use this phenomenon for navigation). The electrons in the air molecules cause a scattering of sunlight in all directions. This explains why the sky is not dark during the day. But when looked at from the sides, the light emitted from a specific electron is totally polarized. Hence, a picture taken in a direction at 90 degrees from the sun can take advantage of this polarization. Actually, the effect is visible in a band of 15° to 30° measured from the optimal direction." (http://en.wikipedia.org/wiki/Polarising_filter)


A recent opportunity in Menorca, while looking for landscape images that would satisfy assignment 5 (Edward Weston style) did bring about the use of a PF. The first two examples below were taken with a very wide angle lens though so the effect on sky and reflection is graduated, which looks natural in the sky by producing receding tones.The two photographs below are "straight" images and have had no post processing. The filter used is a B+W C-POL MRC. 77mm. The time was 15:00 and the sun is to my right at about 90 degrees.



No.1
Nikon D3 17-35 f2.8 AFS - 22mm FL
ISO 400 1/200 sec f14
 Filter at maximum effect.



No.2
Nikon D3 17-35 f2.8 AFS - 22mm FL
ISO 400 1/200 sec f14
Filter at minimum effect.

Careful inspection shows that apart from the darkening of the blue sky the most significant change is in the reduced reflection in the rock pool, mush as I would expect.
At right angle to the rock pool scene I tried the following image to see if there was any significant difference due to the camera being at a different angle now to the sun. The sun is now behind me.


 

No.3
Nikon D3 17-35 f2.8 AFS - 25mm FL
ISO 400 1/125 sec f14
Filter at maximum effect.


No.4
Nikon D3 17-35 f2.8 AFS - 25mm FL
ISO 400 1/125 sec f14
Filter at minimum effect.

 
The difference in the sky is not that striking. In fact No.4 has a slightly darker sky, which is interesting. However, the rock pool refection has almost been completely removed and is an improvement on reflection removal, than seen in No.3.

Conclusion.
While having owned a couple of polarising filters, it has not been a habit to use one, or indeed to test the effects of one, while shooting that often. The reason  (excuse maybe) is that I am a habitual user of a lens hood and on the current crop of Nikon lenses the hoods fit on a bayonet at the outside of the lens barrel and not the 72mm thread. With hoods fitted on the filter thread, it was simple to rotate the hood and the filter. A Gobo (small square card maybe) on a support held onto the camera base could bet around the lens shading issues and give access to the filter.

All the science and the relationship of me, the sun and my subject is likely to be of a secondary consideration when in the field and making landscape images. The primary concern will always be the composition of the image based on some previsualisation in my head of the finished photograph.