The Pentacon Six System
by TRA

How close can I get with the close-up accessories?


The tables produced by Pentacon (here) tell us the width and height of the scene that can be captured with the different close-up tubes, but it is much more helpful to see the difference in some pictures.  This is what I do on this page.

Q: “ Hello
How close can I get to my subject with the close-up accessories?

A: Hello
Here are some examples that will help you to see the effect of using the principal close-up accessories on the Pentacon Six.


The basic set-up
[p615mmtb.jpg]

For these pictures, I am taking pictures of some flowers in a vase.
The following items were used in all the flower pictures:
  • Pentacon Six TL body (with customised covering!)
  • 80mm Biometar except where indicated otherwise (at the end of the first section of this page)
  • Fuji PRO 160 NS film
  • Tripod
  • Pentacon focussing slide (for control of precise distance from subject)
  • Rear cable release for mirror pre-release ("MLU")
  • Front cable release to fire shutter and hold it open during exposures that were longer than 1 second.  (This was replaced with a double cable release for some shots, as indicated below.)

All metering was done with the Pentacon Six metering prism using stop-down aperture metering.  This automatically compensates for the bellows and/or tube extension and any other factors.  However, all metering was carried out at maximum aperture, and then the exposure time was increased as required for the actual aperture chosen.

In the above picture, the 15mm automatic tube is mounted between the camera and the Biometar.


All scanning was carried out on an Epson Perfection V750 PRO , using the supplied SilverFast SE Plus 8 software.  Slight differences of colour or density are probably due mainly to the scanning and image preparation processes.  A second possible factor is that even though all the photos are of the same flowers, some of the pictures were taken on 1st and 2nd April, and others were taken approximately a week later, on 8th and 11th April.  In the course of this time, the flowers changed slightly and also probably had less intense colour.

Using extension tubes and bellows


The 15mm automatic tube
[c309_14_15mm.jpg]

While the flowers were being photographed, the light level changed several times and the subject was re-metered, so the exposure differences do not merely reflect the varying extensions used.


80mm Biometar (right way round), 15mm tube MLU + cable release, 1/8 sec f/16 Lens on infinity (See top picture)
[c534_15.jpg]

 80mm Biometar (right way round) on P6 bellows at minimum extension (i.e., 19mm) lens on 1.2m  Tripod No MLU 20 sec f/16
[c534_6.jpg]
Pentacon Six bellows at minimum extension (19mm)

Note that in these flower pictures, the bright and sometimes coloured spots are not film defects or scanning artifacts (e.g., dust), but little sparkly things that the florist put on the flowers to make them twinkle.


A different picture with the same set-up is shown below.  It was taken about one week after this shot.

The 22.5mm automatic tube
[c309_14_22pt5mm.jpg]

80mm Biometar (right way round), 22.5mm tube MLU + cable release, 1 sec f/16 Lens on infinity 8.4.16.
[c535_2_3.jpg]

80mm Biometar (right way round), 30mm tube MLU + cable release, 1 sec f/16 Lens on infinity 8.4.16.
[c535_1.jpg]

The 30mm automatic tube
[c309_14_30mm.jpg]

Fine focus can beachieved via the focussing ring on the lens, although here the infinity setting on the lens was used.

In some photos on this page the lens distance settings are different.


The 60mm automatic tube
[c309_14_60mm.jpg]

80mm Biometar (right way round), 60mm tube MLU + cable release, 1/2 sec f/16 (re-metered) Lens on infinity
[c534_13.jpg]

80mm Biometar reversed on reversing tube on P6 bellows at minimum extension with special aperture tube with double cable release & lens on maximum extension (See image to right)  MLU 12 sec f/11  At these great degrees of enlargement, the in-focus depth of field is extremely shallow.  It would have been better to have used f/16, as in most of the other photos on this page.
[c534_4-5.jpg]

Bellows on minimum extension, reversing tube, 80mm Biometar mounted back-to-front, special aperture ring on back of lens, double cable release and angle finder
(+ tripod & Pentacon focussing slide)

[revtub01.jpg]
Pentacon Six bellows on minimum extension (19mm)

The back cable release controls the MLU (mirror pre-release) function.  The double cable release at the front stops down the lens aperture on the bellows before firing the shutter.  For the picture to the right it had to be held in (or locked with the locking screw on it) for four seconds.  The angle finder has been turned to a convenient angle to make viewing easier.
[c535_19_setup.jpt]


80mm Biometar + Angle finder  Focussing slide Tripod MLU + dbl cable release, f/16 Assumed 4 sec as prev pic Lens on infinity 11.4.16.
[c535_19.jpg]

80mm Biometar + Focussing slide Tripod MLU + dbl cable release, 4 sec f/16 Lens on infinity 11.4.16.
[c535_17.jpg]
Pentacon Six bellows on maximum extension (100mm)

Even with the tripod at its minimum height, I have needed to put a book under the vase of flowers that is on the floor, in order to bring it within focussing range.  As will be seen from the image to the left, the magnification is so great that the book appears nowhere in the picture!
[c535_17_setup.jpg]

This old Schneider-Kreuznach 150mm f/4.5 Xenar lens came on Novoflex bellows on a Praktisix that looked as though it had never been used.  I decided to try out the lens and bellows on my main Pentacon Six.  Here are some results.

Using a lens with a longer focal length enables us to work farther from the subject -- not critical in this instance, but in some lighting situations the camera set-up could cast a shadow on the subject, or frighten subjects such as small animals, if too close.

[p6novbel1.jpg]

Old Joseph Schneider 150mm f/4.5 Xenar lens on Novoflex bellows extended approximately half way 20 sec f/16
[c534_7.jpg]

Old Joseph Schneider 150mm f/4.5 Xenar lens on Novoflex bellows fully extended
30 sec f/16 (lower ambient light level + greater extension)
[c534_9.jpg]

The Novoflex bellows have their own focussing slide (arrowed in red in this picture), but with the bellows at about 45° from horizontal, I discovered that the bellows section slipped forward on the focussing slide, which was not lockable.  I therefore put the bellows fully forward on the incorporated focussing slide, and used under it a Pentacon focussing slide, which is lockable.


Perhaps the focussing slide on other Novoflex bellows is lockable.  I will have to check.

[p6novbel1c.jpg]

Using supplementary close-up filters


Instead of using close-up tubes and/or bellows, I tried some shots with one or more close-up (dioptre) lenses on the front of the Biometar.  These look like filters, as in the illustration below.


[cu_filters_s.jpg]


1 dioptre

The coverage with a 1 dioptre lens is similar to that achieved with the 15mm extension tube and the Biometar on infinity (see above).


80mm Biometar closest focus + 1 dioptre close-up lens, Focussing slide, MLU + cable release, 1/2 sec f/16
[c534_17-18.jpg]

80mm Biometar closest focus + 2 dioptre close-up lens, Focussing slide, MLU + cable release, 1/2 sec f/16
[c534_16.jpg]
2 dioptre

With the two dioptre lens one gets fractionally closer than with the 15mm tube but not as close as with the bellows on minimum extension (19mm).

3 dioptre

Slightly less close than with the 22.5mm extension tube on the same lens, but much closer than with the 15mm tube.

80mm Biometar 1+2 dioptre lenses = 3 dpt 1/2 sec f/16 Lens on infinity 8.4.16.
[c535_10.jpg]

80mm Biometar + 4 dioptre lens 1/2 sec f/16 Lens on infinity 8.4.16.
[c535_4.jpg]
4 dioptre

Very similar to the effect with the 30mm extension tube.

5 dioptre


Ready to take the picture to the right, using the 4 dpt & 1 dpt close-up lenses.
[c595_16_setup.jpg]


Detail of close-up lenses on the Biometar
[c595_16_setup_cu.jpg]

80mm Biometar + 4+1 dioptre lenses = 5 dpt 1/2 sec f/16 Lens on infinity 11.4.16.
[c535_16.jpg]

80mm Biometar + 4 dioptre + 2dpt = 6 dpt lens 1/2 sec f/14 [in error!] Lens on infinity 8.4.16.
[c535_5_6.jpg]
6 dioptre

After having taken the picture, I discovered that while handling the lens I had unintentionally opened up the aperture from f/16 to f/14.  Such a half-stop difference in exposure is well within the lattitude of modern films.

However, in macro photography such as this, the slight reduction in depth of field as the lens is opened up may be visible in the resulting picture.  The centre of the bottom edge of the image is in focus and is sharp, but the top left and right corners are further away and clearly out of focus.


7 dioptre

“Received wisdom” states that when dioptric correction lenses are used on the front of the lens, image quality will be inferior to that obtained by the lens alone with extension tubes or bellows.  It also states that combining such lenses will result in significant aberrations round the edges of the picture.

With flower pictures such as these, any shortcomings are not visible.  The shallow depth of field does in any case throw part of the image out of focus.

If we were photographing newsprint or a line drawing with fine detail (for instance, an Albrecht Dürer print), any shortcomings might become visible.  Of course, we might choose to scan a newspaper article, but we might not be allowed to do that with a precious and delicate Albrecht Dürer print!


80mm Biometar + 1+2+4 dioptre lenses = 7 dpt 1/2 sec f/16 Lens on infinity 8.4.16.
[c535_8_9.jpg]

80mm Biometar + "Macro" dioptre lens (believed to be 10 dpt)  1/2 sec f/16 Lens on infinity 8.4.16.
[c535_7.jpg]
10 dioptre

This close-up kit has four lenses, marked +1, +2, +4 and “Macro”.  The publicity for the kit indicated that the “Macro” lens had a power of +10.  It would seem to me that for most photography one would be unlikely to require anything more powerful, unless one were photographing much smaller subjects.


I hope that this is helpful.

With best wishes

"Mr Pentacon Six"                                                                                                                                  Thank you to Rubén, Lidia and the boys for the flowers!

To go back to the introduction to the macro section, click here.

To go back to the frequently-asked questions, click here.

To choose other options, click below.
Home

© TRA First published: April 2016  Revised and extended: May 2016