Eurico Melo

FOTÓGRAFO

Notes on Cameras and Lenses

HASSELBLAD  500C 

For portrait the 4/ 120 macro is an amazingly good and very practical lens, but at the shortest focusing distance the picture still covers a field of 30x30 cm. With the 32 mm extension tube the smaller subject side is 12x12 cm, but it is very annoying to be constantly inserting and removing the extension ring in the course of a photographic session.

Note: Do not to use the standard 80 mm lens with 32 mm or bigger extension rings for macro photography due to the noticeable barrel distortion. 

HASSELBLAD  SWC

Positive: Once you master it you can do portrait and studio photography with it. I have never used a better wide angle.

Negative: You need much practice before you know how much of what you see (and do not see) in the viewfinder is going to be included in the picture.

HASSELBLAD  FLEXBODY

Positive characteristics: Enough tilt for depth-of-focus control in the studio. No noticeable vignetting with the 120 mm macro at maximum tilt (30º). Practical and cheap (if you already have the adequate lenses and backs of the Hasselblad system). Very convenient for semi-macro photography.

"Negative" feature: Useless concerning perspective control (not enough shift), but this is a correction that is easy to make in Photoshop.

DUST AND FUNGUS

There are long discussions in the net about this subject, and many say that localized dust spots or scratches do not affect the image quality. My experience is that blemishes in, or near, the optical axis will spoil the lens performance.

The problem of fungus on the lenses may be solved the cheap way by exposing them periodically to a UV lamp. But I am not sure that UV radiation will not affect the glue between some optical elements.

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Scanners and Scanning Techniques

NIKON  COOLSCAN  8000 ED

I am totally happy with it. Having found much confusion on the net about what settings are the best, I have made my own tests with the film I use, Fuji Reala 120, and the conclusions are as follows (obviously only valid for Reala): 

(i)     Focus: Place the focusing tool in a contrasted region you want to be in precise focus (the flatness of the film is seldom perfect).

(ii)   ICE: ICE is very efficient and the best setting is Normal. With this setting I have not noticed the degradation of image quality some claim to exist. With Fine the sharpness is degraded, as stated in the Nikon instructions.

(iii)  GEM: It is advisable to set GEM at 2 or 3 (default) for all scans. This will avoid odd colored pixels when the Unsharp Mask is applied. The sharpness of the image is not affected, and the graininess of the smooth surfaces is avoided (se pictures below). With GEM 4 there is a disagreeable flattening of some less contrasty regions. 

(iv)   Super : Scans of color negatives often show banding. The only way to avoid it is to scan with "Super fine scan" selected. I noticed that performing a calibration immediately before the scan often reduces drastically the banding. I haven't observed this banding with normally exposed slides.

(v)    Multisample: Multisample makes a more clean scan (see pictures below), but the time a 16x takes is outrageous. For my work I find that GEM(3) is more useful, and less time consuming, than multisampling.

(vi)   Bit depth: I always scan at 14 bit. This is a personal choice, and depends a lot on the methods used for manipulation of the image in Photoshop. It seems that there is a bug in the autoexposure algorithm of Nikon Scan, leading to a compressed histogram (the first 30 levels are not used). With 8 bit per channel scanning this is an important loss.

(vii)  Color accuracy: The colors obtained are not perfect. I have partially circumvented this problem by photographing a Kodak grayscale and forcing the patches to be neutral and the medium gray 127. This may be done directly in the Nikon software but it is easier to use Photoshop Curves and save the resulting conversion pattern in a file for use with all the images done with the same film (this also corrects for the above-mentioned autoexposure bug). A better solution is to switch to the reasonably priced software ViewScan. I use it for negatives with great satisfaction. Contrarily to what is said by many, I find it slower than NikonScan, but it pays for the extra time spent,  giving a good color balance for negatives. A must!

(viii) Color space: I use Adobe RGB (1998). It seems adequate for image manipulation and printing. An alternative is to use Bruce RGB or a wide-gamut space such as the Ekta Space of Joseph Holmes, or Kodak ProPhoto RGB, for the raw scan, the one that you store, and then convert to a more modest space for manipulation (discussion of the advantages and disadvantages of each approach by Bruce Fraser). 

Negative 0.4 x 2.7 mm

In the pictures we compare the effect of 3 different scan settings on the same regions of a MF Reala negative scanned at 4000 ppi with the 8000ED. 1) ICE Normal 2) ICE Normal + GEM(3) 3) ICE Normal + GEM(3) + Multisample(16x) The images are sharpened (200%, R(1.0), T(0)) and the contrast increased to enhance the artifacts. JPEG compression did not masked the defects present in the images. Notice also the difference in color, namely in the case of the 16x scan.

Negative 0.6 x 0.6 mm

Software

NEAT IMAGE 

Neat Image  is magic in reducing the noise always present in digital images, whatever its origin. For low-light photography, where CCD noise becomes disturbing, it is a must. However, without a careful use it results in plastic-looking images.

THUMBS PLUS

Thumbs Plus is a very convenient program to catalog images. It recognizes 48bit, RAW and PSD images, between many others, and maintains a constant track of the offline archives.

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B & W

After my conversion to digital I seldom use B & W film. I prefer to photograph in color negative and do the conversion to grayscale in the computer. The advantages are: 

(i) I can have two versions of the same photograph, or mix color and B & W in the same picture.

(ii) The classical filters from B & W photography can be simulated and applied only to the selected regions in the image.

(iii) The darkroom is a much less comfortable place than my office.

However, there are disadvantages that should be considered: 

(i) The exposure latitude of color negatives do not exceed 5 f-stops which is not the case with certain b&w films (see below). This is a serious drawback for me, because often I need to include in the same picture a black cloth, a well-modeled skin and detail in a bright (eg. silver) object.

(ii) The characteristics of the grain of b&w films, which is part of their character (eg. Tri-X), is no more present. In any case it is partially lost in the conversion to digital even with the 8000ED at 4000 ppi, as you may observe in the picture at the end of this section (some say that this is not the case with drum scanning).

Conversion of color to grayscale in Photoshop

Each photoshopper has his/her own preferred technique to convert color to grayscale. I generally use the prosaic "Channel Mixer" method described in detail in several textbooks and websites. I am not dissatisfied with it but I wouldn't claim it is the more flexible tool for fine-tuning.

For a detailed description of the Photoshop Channel Mixer technique follow this link.

B & W  FILMS

When it is necessary to register in the same picture dark clothes and shiny metals or stones, maintaining the texture of both, either an emulsion with an extended  D vs. log E curve, or a N-i (i = 2 or 3) development has to be used. I like better the look of the images obtained with the first approach and printed with selective burning and dodging. With the purpose of selecting the best film for such images I have tested the following film/development matched pairs: 

Kodak TMY in Tmax 1+4(24 ºC) and D76 1+1(22 ºC)
Kodak TMX in Tmax 1+4(24 ºC) and Tmax 1+7(24 ºC)
Agfapan APX-25 in Rodinal 1:25(20 ºC) and Rodinal 1:100(20 ºC)
Agfapan APX-400 in Rodinal 1:50(20 ºC)
Ilford Delta 100 in Rodinal 1:50+12g/l sodium sufide(20 ºC) and XTol 1+1(20 ºC).

Best choices are:

1) Agfapan APX-25 in  Rodinal 1:100 (20 ºC) 12.0 min, E.I. 12, last Zone with detail XIII !

2) Kodak TMY in Tmax 1+4 (24 ºC) 4.5 min, E.I. 320, last Zone with detail XII

The deceased APX-25 was a wonderful film but a little too short in sensitivity, while TMY has a rather excessive (and unpleasant) grain. The best alternative is the Delta 100 developed in XTol 1+1 (20 ºC) for 10.0 min with an E.I. of 100. It has virtually no grain, but the last zone with detail does not go beyond Zone IX.

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