Post Updated: Infrared camera conversions and channel swapping. Can files be processed in the new Nikon Capture NX-D?

I have found out more on continuing to explore NX-D. I have therefore modified yesterday's post on this topic.

Infrared camera conversions and channel swapping. Can files be processed in the new Nikon Capture NX-D?

With Nikon Capture NX-2 now discontinued, I had heard dire rumours of the very much downgraded but free ‘replacement’ Nikon Capture NX-D. Gone have those features like Control Points that made Capture NX-2 such a powerful bit of software. I was keen to find out if NX-D could be used for infrared colour conversion like NX-2 from cameras, like my old D70, having a suitable filter over the sensor (mine has a 715 nm filter).

At this stage I should say that I have two methods of ‘channel swapping’ on my iMac. The first is via the channel mixer in the add-on application to Photoshop Elements, Elements+. I do that step from Aperture with Elements selected as the external photos editor. I also add a hue adjustment layer there, adjust the R,G and B channels if necessary and then go back to Aperture for the final editing.

My second method is the one involving Capture NX-2. I use Catapult to move the files to and from NX-2 (see my post of 25 August 2012). The reason for using this method is that I found that I could get different appearances from the same initial image.

The method I use in NX-2 was described by Jeff Meyers in a post on the Nikonians website. You can follow the link to see his full description but the key part—equivalent to channel swapping in Photoshop—are these steps:

4. Now, here's the cool part. Click on the "New Step" button. Select "Color" and then "LCH" from the pull down menus.

5. Click on the pull down menu that says "Master Lightness" and choose "Hue." That will bring up a colored hue box. Below the box there's another pull down menu. Click that and select 180. Notice that the hues have all slanted.

6. Go to the triangular slider on the right side of the box. Slide it about two-thirds of the way up until the red and blue channels are switched. Watch your image. You'll want to experiment with the best place to put that slider. The red sky has now become blue.

So, can you do that in Capture NX-D? The answer is yes. Here are screen grabs showing the appearance of the control before and after swapping the channels; with the latter the sky has turned blue. With my filter and white balance I move the slider on the right all the way to the top.

I have found something odd with NX-D that prevents the straightforward use of Catapult between it and Aperture. If you right click on a raw Nikon image and choose Open With, NX-D does not appear (NX2 does). If you then force that by choosing All Applications from the box, a message appears stating that the file format is not recognised by Capture NX-D. That is rubbish because by choosing the same file from within NX-D, the file is recognised. 

I think it is for this reason that Catapult cannot open NX-D as it can NX-2. However, in coming up with the error message when trying to export to NX-D from the latest version of Catapult the image usually appears in NX-D anyway!

Catapult uses a scratch folder with two folders within it: Drop Folder and Pickup Folder.

From Aperture with the image selected, I choose Photos - ‘edit with plug-in’ - Catapult

In the Catapult box’s upper (export) panel I untick the ‘open with’ box but leave Drop to as Drop Folder. I then press Export, then Done which quits Catapult.

In NX-D I then open the file from Drop Box, do the necessary editing and then save it to the Pickup Folder as a tif jpg (BUT not the raw nef). In Aperture, selecting the same image as before, I again choose: Photos - ‘edit with plug-in’ - Catapult. This time I import the edited image from Catapult to Aperture. Catapult adds that version to the stack for that image and places them together.

There is no doubt that NX-D is a major downgrade from NX-2 shows how careless Nikon have been again with their software and its customer base, many of whom have not forgotten the desertion of their software for Nikon scanners.

There are all sorts of things I want to try in NX-D, like batch processing. However, although it can be used for infrared processing, sadly lacking are the Control Points of NX-2. However, for those with an infrared-converted camera, processing is possible with the free NX-D. The full Photoshop or Elements plus Elements+ are not necessary for the channel-swapping stage. However, NX-D would still not be my preferred editing software for infrared conversions. I find Aperture and the Elements/Elements+ combination much easier to use and the attraction of control points has gone. However, there are other possible combinations I have to try and should I no longer be able to use Capture NX-2 either as operating systems are upgraded or cameras appear which aren’t covered for raw files, I shall still have several ways of getting the look I want from photographs taken with different IR filters.

I am now left with concern over how much of a downgrade Apple Photos will be as a replacement for Aperture 3…but that’s for the future.

Added Note: I have found that White Balance can be changed in NX-D by using the grey point method (as in NX-2) so that the result using the LCH, Hue 180 etc step can be modified by going back to changing the grey point in white balance, just as in NX-2.

Time to ditch the tripod bush?

Walking closely behind a photographer with a long lens and camera on a tripod, or behind a birder with a telescope or digiscope combination on a tripod, can be hazardous as legs, camera, lens or scope move in all directions. It can also be nerve racking. The £10,000 camera and lens suddenly become loose and fall to the ground. Fortunately, when I saw this happen, the camera and 400 mm lens landed in thick scrub and were unharmed. Another few steps and that expensive combination would have landed on sun-baked, hard earth. Another trip on the same continent saw the telescope falling off inches away from an African escarpment. Only some fast foot work by the person walking behind saved it from rolling downwards a thousand feet.

The common factor in these near horror stories is, of course, the tripod bush. That small threaded hole is also responsible for lost shots and lost sightings because the attachment becomes loose and the long lens cannot be aimed properly. Frequent stops to tighten the screw are a common occurrence during wildlife photography and viewing expeditions.

The universal tripod bush with its own ISO specification is, regardless of whether it is 1/4 or 3/8 inch, to use that hackneyed phrase of politician-speak, not fit for purpose. It does not fasten, it merely attaches the fitment for a while until the latter is shaken loose by movement. Of course, a tiny camera will stay fixed but the torque from a long lens being carried on a tripod soon loosens the screw fitting even when considerable force has been used to tighten the screw before use.

Several ways of securing the screw fitting between tripod or tripod plate and camera, lens or scope have been suggested, for example, the anaerobic adhesives that lock screw threads and plumbers’ tape. These bodges work for a time but always eventually fail at a critical moment. One telescope manufacturer made a fixing foot to fit directly into a proprietary tripod head in order to avoid the use of the bush. I also see that a manufacturer of light adventure video cameras has devised a different method of attaching the cameras to supports. But the mainstream user of long, heavy lenses has nothing but the unreliable screw fixing into the tripod bush.

So, can anything be done not only to prevent the disaster of a falling camera-lens combination but to remove the worry that it might happen. Surely, the mechanical engineers out there can come up with a simple, effective solution. All that’s needed then is for all the camera, telescope and tripod manufacturers to agree on a common fitting. Ah yes, that last bit might prove more difficult than the first but the message is: consign the threaded tripod bush to the history books; we need something better.

Superzoom Bridge Cameras for Birders: Latest Reviews

A very useful compilation of reviews has appeared today in ePhotozine which ranks current models of superzoom bridge cameras. Now, their definition of superzoom and my definition of superzooms useful to birders (extending to the equivalent of at least 1000 mm) differ and so you first have to exclude the cameras that do not reach my definition, including their number one in the ranking.

One of their equal seconds, the Panasonic Lumix FZ72 (20-1200 mm equivalent, RAW and what seems like pretty fast focusing) looks very tempting. What's more there is available a tele-extender to take the optical zoom range from x60 to x102 (at the cost of loss of light reaching the sensor of course).

The price of these superzooms is very low for what you get and I wonder if a manufacturer will take the plunge to go for a better electronic viewfinder (more dots and faster refresh rate). Birders and wildlife watchers would probably pay twice the price for a top of the range model that did all that they really wanted. Compared with a reasonable pair of binoculars, a bridge camera at present is a drop in the financial ocean.

I suspect that all the manufacturers have been slow to catch on to the wildlife market. Feedback from the the amateur photography market (which ignored these cameras for years) is a limited source of to manufacturers who often do not realise what a large part of the market is looking for. After all, remember the axiom: cameras are designed by people who never use them to sell to amateur photographers who own but never use them.

This is the link to the ePhotozine article:
http://www.ephotozine.com/article/top-10-best-ultra-zoom-bridge-digital-cameras-2014-16928

British Journal Photographic Almanacs in the 1950s: How were the photographs selected?

It is a mystery how the photographs that appeared in a special photogravure-printed section of the old British Journal Photographic Almanacs in the 1950s were chosen. Some were superb; others were dreadful. 

Roger Hicks it was I think who in one of his articles stated that many old photographs were actually very poor photographs. Excluding even the kitsch still lifes and the banal pictorialism, there were still some really poor images selected for the BJ Almanac amongst a few that were superb examples of photography of that era. Some it would seem were gleaned from superficially prestigious amateur photographic exhibitions held in the previous year. Whatever the selection method used by the editor from 1937 to 1967, Arthur J Dalladay (1894-1989), his choices often left a lot to be desired. So much so in fact that one might wonder if being in the same club might have been one criterion.

One of the worst—if not the worst—to be found in those volumes was a female nude by a Cecil J Blay. I will not reproduce it here because it doesn’t warrant being given more air than it got at the time. I was trying to find out who Cecil J Blay was when I remembered I has seen the name somewhere before. A Google search reminded me. He was a frequent photographic contributor to model railway magazines. He lived in Reading in a house backing onto the Great Western line from Paddington. He was elected a Fellow of the Photographic Society of America in 1950 and was the link in UK for photographic competitions in the USA.

Blay appears in Google searches mainly for his religious tracts which still seem popular with Americans of the christian persuasion. The author of those would appear to be the same Cecil J Blay since his dates (1916-1976) shown on one website are nearly the same as those for the registration of his death in the Reading and Wokingham Registration District (1906-1976) if one accepts the 1 in 16 is a typographic error.

Other than that I do not know if Blay was other than an amateur photographer, if he was a man of the cloth (many railway enthusiasts were) or how, other than as a member of a charmed circle, he got his female nude into the BJ Almanac.

Scanning Kodak Elite Chrome 100 and Ektachrome 100 Plus

I scanned a couple of hundred Elite Chrome 100 slides (plastic mounts) for #2 son. I had the Nikon LS-40 ED (Coolscan IV) handy and used the latest edition of Vuescan (9.4.40). The results were superb, some of the best non-Kodachrome scans I have seen. This film from the late 1990s though was very 'grainy' or 'dye-cloudy' especially in some underexposed areas and had a magenta cast (variable between individual films) that was easily corrected. A 36-exposure Ektachrome 100 Plus (early 1990s) had a much cooler cast (very Ektachrome) but again produced excellent results from the twenty-year old transparencies. For both I had the IR dust removal on. 

Which Binoculars for Birding: Insights into Optical Design

Following up my post on the new Zeiss Victory SF binoculars, the most useful website for those seeking real information on the optical design of binoculars is that of Holger Merlitz who is Professor in the Department of Physics at Xiamen (Amoy to old China hands) University in China. His articles and papers are well worth reading and I have included links below to those of particular interest to this post in relation to the history of optical design, the introduction of intentional distortion and the characteristics of binoculars from different manufacturers.

The first major point to bear in mind is that the design of lenses for cameras differs (or should differ) from that for binoculars because the imaging system of binoculars includes the human eye which has its own distortions. The camera lens is aimed at the ideal of distortion free imaging; the binocular is aimed at the optimal image on the human retina, taking the binocular and eye as the integrated unit.

The history of the realisation that the unit to consider is binocular+eye is interesting and is outlined by Merlitz. Before 1950, optical designers tried to produce binoculars that, like camera lenses, were free of distortion (roughly defined as an absence of barrel or pincushion distortion). In 1949 Zeiss (Jena) picked up on the complaints of some army, presumably German, officers in two World Wars that when panned across the battlefield their binoculars or field glasses produced a strange effect that made them feel nauseous. As Merlitz puts it:

…appeared to display a rather strange kind of distortion, which became particularly obvious whenever that binocular was used for panning. The moving image appeared to roll over a curved, convex surface. This phenomenon, henceforth denoted globe effect, seemed to be absent with the static image, but it miraculously reappeared with the moving image each time the binocular was panned.

Koehler and Sonnefeld at Zeiss Jena, then in East Germany, suggested and demonstrated that this globe effect could be eliminated by introducing a degree of pincushion distortion into the binocular design. The human eye counteracts that pincushion bending of verticals and horizontals to send an image to the brain that is undistorted. Such a design of binocular would therefore be fine for both static spotting and panning. From the 1950s binocular manufacturers began introducing pincushion distortion. However, the degree of pincushion distortion employed can be noticeable and from about 2005 some manufacturers reverted to pre-1950 practice but in so doing exposed their customers to the globe effect and the feeling of nausea that it may induce.

More recently there has been renewed interest in the amount of pincushion distortion that should be added. Merlitz has tried to determine whether there is a point at which the globe effect is eliminated and noticeable pincushion distortion is minimised. I will not go into any detail of the geometry and trigonometry used to calculate theoretical levels of distortion here since they are fully described by Merlitz. suffice it to say that Sonnefeld, it seems, overestimated the degree of pincushion distortion required to overcome the globe effect. If k is the amount of pincushion distortion deliberately introduced and k = 1 is no distortion at all (termed the tangent condition and where the globe effect is evident), Sonnefeld suggested a value of 0 for k (the  angle condition). Other calculations from the work on human vision by another member of the Zeiss design team in the 1940s suggest a value of 0.5 (the circle condition).

More recent research by a group at Delft University in the Netherlands as well as that by Merlitz suggested that k should be between 0.6 and 0.8.

The more recent research brings out the second major point: there is variation between individuals on the value of k at which pincushion distortion can be perceived. For those interested, Merlitz shows Helmholtz checkerboards you can use to find your value of k (subject to variation in experimental conditions). Merlitz argues that the true average of k in the 56 people who responded to his request for help was around 0.7. Three of us here did the same study, finding values of 0.6, 0.7 and 0.8.

The major points throw up interesting challenges to the binocular manufacturer, as Merlitz points out:

Which consequences are to be drawn for the binocular manufacturer? With a choice of pincushion distortion near k=0.7, the majority of users would not complain about any globe effect. To be on the safe side, one might want to go a little lower, perhaps between k=0.6 and k=0.7, accepting a little bit of an extra pincushion distortion. In any case, the extremes should be avoided, namely values of k<0.5 (too much pincushion) or k>0.8 (too much of a globe effect).

and

It therefore appears that the ideal amount of distortion for handheld binoculars should be chosen between k = 0.6 and k = 0.8, a choice that would leave both the globe effect and the pincushion distortion (with the rolling eye) on a reasonably low level.

Merlitz also stated:

Binocular designers might also considering building oculars that would enable the user to modify the amount of distortion. In this way, the observer would be able to optimize the distortion characteristics of his instrument according to his own individual preferences and the particular mode of application.

As far as I know no manufacturer has yet done this and until one does, given the variation in different individuals, binoculars from one manufacturer may be more suitable for some individuals than those from another, depending on which k value is being incorporated in the optical design. If manufacturers stated the degree of pincushion distortion they have employed and retailers could test the k value of individual customers using Helmholtz checkerboards under proper test conditions, a better match might be achieved than by competitive birders buying binoculars for their brand badges—‘I’ve got to ‘ave Swarovskis ‘cos all my mates would laugh at me if I didn’t’, as I heard one checklist ticker say to another.

So what do we know of different manufacturers and their newer products. Well, here Merlitz helps again: From modern Nikons returning to pre-1950s undistorted optics and, therefore, the rolling ball effect when panning to the latest Zeiss Victory SF adopting a k value of 0.7, as recommended by Merlitz.

Of course there are many other optical and ergonomic factors in buying binoculars in a given price range, a sufficient number in fact to provide binocular nerds with hours and hours of discussion. But if you use binoculars to pan across the landscape, you need to read Merlitz and take note or you could end up with an the unpleasant rolling ball phenomenon and motion sickness if you choose a brand with undistorted optics.

---------------

1. These are all key pages in Holger Merlitz’s Website:

http://www.holgermerlitz.de

Merlitz, H. 2010. Distortion of binoculars revisited: Does the sweet spot exist? Journal of the Optical Society of America A 27, 50-57

http://www.holgermerlitz.de/globe/distortion_final.pdf

Distortion of the new Zeiss Victory SF: A paradigmatic shift on the binocular market?

http://www.holgermerlitz.de/newk/newk.html

2. Globe effect

http://en.wikipedia.org/wiki/Globe_effect

3. Oomes AH, Koenderink JJ, van Doorn AJ, de Ridder H. 2009. What are the uncurved lines in our visual field? A fresh look at Helmholtz's checkerboard. Perception 38, 1284-1294