Two Replicas of Historic Buildings

[OlDoinyo]

These images were obtained with the Sony A900 at ISO 100, the Asahi 35mm lens set at f/16, and the Baader U2 filter. Display intent is BGR.

 

The first building depicted, in Fort Goryokaku in Hakodate, was built from 2006 to 2010; however, the original Bugyo-sho it replicates was built in 1864-66, and only stood briefly before being razed in 1871. The fort itself is noted for being the site of one of the last battles of the Boshin War.

 

"Goryokaku Magistrate's Building:"

 

 

The paint on some parts of the structure is titanium-dioxide based, whereas elsewhere it may be something calcimine-like which does not absorb UV..

 

The second building featured here is from a site with a longer history. The ruler Toyotomi Hideyoshi built the first fortress on this site in 1583-85; the original keep was destroyed after the compound fell to Tokugawa forces in the Summer War of 1616. Four years later, the Tokugawa family built a larger keep within the compound a few tens of meters from the spot where Toyotomi's keep had stood. This second edifice burned down after being struck by lightning in 1665, and only the ruined foundations stood on the site for the next two and a half centuries. The present structure shown in this photo was built as a public museum in 1931, in the exterior likeness of the Tokugawa keep and on the foundations of the former; however, it has never been a residence or fortification, and the interior is modern.

 

"Osakajo Museum:"

 

 

The exterior paint on the outside of the structure does not contain titanium dioxide, as is seen from its relative lack of color. It is possible that it is either calcimine or older lead-based paint. The gilded areas do not show color; this has been seen before in UV images.

 

As an amusing contrast, here is a single-exposure IRG image of the same scene:

 

 

In this case, the filter was swapped out for a Tiffen 12 and an algorithm in Adobe Pixelbender was used to reconstruct the channels.

[Andy Perrin]

Pardon, what is the IRG picture? It's quite pretty. I don't know that acronym. Google says Tiffen 12 is a yellow filter?

[OlDoinyo]

IRG, short for IRG-->RGB cross-sampled image: red depicts the IR signal, green depicts the red signal, and blue depicts the green signal. Such images originally appeared in an old family of Kodak films, although the example above is digital.

[Guest]

Could you explain how this cross-sampling is done? Pointedly, how are IR, red, and green signals isolated from a single exposure?

[OlDoinyo]

In the original film, it was done by including an IR-sensitive emulsion layer, filtering out the blue light, and scrambling the dye couplers (relative to their normal emulsion-layer pairings.)

 

In a single digital exposure, the same filter isolates the IR signal in the "blue" channel (which is assigned to red in the output;) the IR signal can then be subtracted in the appropriate amount from the "red" and "green" channels (which are assigned to green and blue output.) A Canadian photographer worked out the math for this operation. The result is not perfectly accurate because the IR signal obtained has less of the 700-760nm component than what is seen in the "red" channel; however, it is close enough for artistic work. A more exact method, suitable for scientific use, is to use separate visible and IR exposures and merge the relevant channels in post-processing; this method is largely limited to static subject matter when using an ordinary consumer camera, although multi-camera arrays have been constructed to get around this limitation.

[nfoto]

"IRG" goes under a variety of names. Amongst these, "Emulated Infrared Ektachrome" or "False-colour Infrared" is often seen.

 

I try to emulate the oldest type of Infrared Ektachome, (IE 2443 etc.; the kind developed in E-4 or AR-5) as this film had much more subtle and delicate colour rendition than the later quite garish EIR for E-6/AR-6.

 

Many digital cameras (or photographers?) veer towards to "EIR" look though, but I found the Fuji S3/S5 to be pretty consistent in their IE-"lookalike" rendition.

 

English is not even my second language, but nevertheless my ears cringe at the title "historic replica buildings". Shouldn't it rather be "replica of historic buildings"? There is a subtle yet quite significant difference involved here.

[OlDoinyo]

Mea culpa on the title--it did not sound quite right to me either, but my fogged brain (dealing with a recent 14-hour time change) could not come up with a better version. I have fixed it now, although the second example could be argued to be old enough to be "historic" in its own right.

[Cadmium]

Clark, very appealing 'EIR' Tiffen 12 shot. I was never able to get results I liked using the Pixelbender method, but maybe I didn't have it setup right. Very nice.

[Bill De Jager]

English is not even my second language, but nevertheless my ears cringe at the title "historic replica buildings". Shouldn't it rather be "replica of historic buildings"? There is a subtle yet quite significant difference involved here.

 

Bjørn, in terms of good English you are correct. However, in the current era of euphemisms "historic replica building" sounds exactly what these structures would probably be called in the U.S. The authorities would do that to make the description sound better to those native speakers who are not discerning, including themselves.

[Andrea B.]

"current era of euphemisms" :D

Ain't that the truth!

---

 

I had not heard of the Tiffen12 and the IR algorithm before. How does one subtract a signal in a digital file?

[nfoto]

Tiffen 12 == K12 in old Kodak literature, is a medium yellow filter used in conjunction with Infrared Ektachrome to cut down the blue response.

 

One subtracts by the Photoshop command Image > Calculations > Subtract (other operators are Multiply, Add)

[Andrea B.]

Aha!

You see, I quit using Big Photoshop. Too many un-needed tools.

So I only have Little Photoshop to back up my other converter/editors for some simple layering on the rare occasion I need it. And it does not have Calculations.

But still, subtraction? You are subtracting RGB values or what??

 

K12, yes I know the filter this way.