Ikonta 520 novar

This is a medium format camera (i.e. takes 120 film) from Zeiss Ikon.  It is a half-frame camera - 6 x 4.5 cm negative - which is half of a standard 120 frame of 6 x 9 cm.

Ikonta 520, front view

lens: Novar
focal length:  75mm
apertures: f6.3 to f32
focus range: 4'6" to infinity (that is the scale, actually about 4 feet)
lens fitting: fixed
shutter: Derval
speeds: 1/25, 1/50, 1/100, B, T
flash: n/a
film size: 120

The body is made from cast aluminium.  This body casting is shared between the Ikonta 520, Bob 510 and Nettar 515. It is quite hard to understand why Zeiss Ikon shared the body between three different camera lines instead of calling them all Ikonta (the oldest name) seeing as Bob, Ikonta and Nettar all come with a range of lenses and shutters and can be considered to be one range in effect if not in name.

So, this Ikonta.  The lens is a Novar which is a triplet and performs surprisingly well once stopped down to f8 or smaller.  Ikontas were also available with Tessars at a higher price and wider aperture Novars.  The Novar on this camera is quite a slow lens with a maximum aperture of f6.3.  The focussing is front cell only, rather than the whole lens moving (giving not quite so good image quality) and the focussing scale is in feet indicating that the camera is an official import into the UK.

The shutter is an everset Derval (everset means it does not need cocking before firing as a Klio or Compur would).  This is a fairly crude (and so cheap) shutter with two blades only and only offers three speeds: 1/25, 1/50 and 1/100.  With a slow lens like this camera has, faster shutter speeds would have been superfluous, particularly with the slow, by modern standards, films available in the 1930s.

Detail of rim-set shutter adjuster on Derval shutter

The shutter is a dial set shutter which means that the speed adjustment is by a dial set above the shutter housing.  More modern shutters have a rim set adjuster which is a ring around the shutter housing.  This shutter does not have a V (=Vorlaufwerk) setting for delayed action and as is usual with cameras made before the late 1940s, there is no flash connection or synchronisation.

As I mentioned, the maximum aperture is rather small at f6.3 but the minimum aperture is surprisingly small - f32 - so the range of exposures possible is still respectably large.

A standard photograph with this camera (as with the Bob 510 and Nettar 515) is in portrait format and in this orientation the shutter release is underneath the camera and is uncomfortable to use.  To take landscape pictures, the camera must be used on its side and the shutter release is on the side and easy to use.

Praktica TL3 mayer

Praktica TL3, front view

lens: Meyer-Optik G?rlitz Domiplan
focal length:  50 mm
apertures:  f2.8 to f22
focus range: 0.75m to infinity
lens fitting: 42 mm thread
shutter: metal vertical focal plane
speeds: to 1/1000
flash: bulb or electronic
film size: 35 mm

This is a standard looking camera from between 1984 and 1986.  It is a fairly heavy (very heavy by modern standards) and large enough to hold in two hands.  The ergonomics - the layout of the controls - is, again, normal for the time.

This camera takes 42mm thread lenses (also known as Pentax thread) which means that lenses are readily available.  It is specifically designed to work with automatic lenses (those with a pin to stop down the lens) - when the shutter is fired, a cam presses the pin and closes the aperture.  This is not essential, though, and the camera works fine with fully manual lenses.  I have shot half my test film with my Soviet Helios-44 lens from my Zenit E.  So long as you remember to manually stop the lens down for both metering and picture taking there is no problem.

This is a fully mechanical camera and no battery is required for its operation.  It does, however, use a battery for the metering system.  This should be a mercury battery giving 1.3 volts but these are no longer available.  I am using an alkaline 1.5 volt alternative which 'should' cause the camera to underexpose but I have checked the results of the built-in meter with my Ikophot meter and they are in complete agreement.

This is an SLR camera and so both metering and focussing are conducted through the lens (known as TTL, for the uninitiated).  With an automatic lens fitted, metering is done by selecting either the shutter speed or aperture, holding down the metering lever beside the shutter release and the adjusting either the aperture or the shutter speed until the needle in the viewfinder is as close to the circle as possible (i.e. it is a match-needle meter).  With the supplied lens, this is within 1/2 stop of 'perfect', with the Helios-44 it is to the nearest whole stop.The meter can be set to a range of film speeds from 12 ASA/12 DIN to 1600 ASA/33 DIN.  It is settable in 1 DIN stages which equates to 1/3 stop.

top and rear view

The shutter is a vertical metal focal plane shutter.  It has a good range of speeds - up to 1/1000 seconds which is plenty fast enough for my photography.  There are two flash synchronisation speeds: 1/30 for bulbs and a separate position on the speed selector dial for electronic flash, which the manual says is 'about 1/125.  Both bulbs and electronic flash can synchronise at slower speeds.

Electronic flash can synchronise at 1/125 seconds (quite a high sync speed for the time) because this camera has a vertical shutter with three metal blades.  In the manual, Praktica tout this as a modern invention but Zeiss Ikon used a vertical metal shutter in the Contax I in 1932

The shutter release is not my favourite part of this camera.  It is placed on the front of the camera rather than on the top plate which I always find awkward.  Secondly, the shutter release has to be pressed flush with the housing.  this might be just my camera but a little less travel would be good. The film winder is a lever which travels through 180 degrees but the first 20 or so degrees do nothing.

On top of the prism is an accessory shoe which has 'hot' contacts for a flash gun.  This is the only way of connecting a flash gun as there is no PC connector.  The only other control on the top plate is the film rewind crank.  As was normal for the time, this is an annoyingly small folding crank.  in the early 1960s several manufacturers introduced a large rewind crank on the base plate and it is a pity this did not become the standard.

Pressing the shutter release, you experience a significant resistance and then there is a loud and tactile 'clunk'.  I had thought my Zenit E had a heavy action but this is much worse.  I am hoping that most of this is the mirror slapping up and not the shutter.

The supplied lens is a Meyer Optik Domiplan f2.8 50mm lens.  this is a triplet lens and a cheap option.  I have yet to see the results of this lens but I have a 50mm Domiplan on my Exa IIa and that lens is fine.  Available apertures are from f2.8 to f22 in 1/2 stop clicks.

Focussing is from 0.75m to infinity and the focussing scale is in feet as well as metres.  The action is fairly stiff and changing the focus from near to far will result in the lens unscrewing rather than focussing.  Hopefully, this is lack of use and will sort itself out with use rather than being down to physical damage.