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photo:bronicasq

Bronica SQ 6x6 medium format film system

 

NB. $US prices quoted are the list prices on Tamron's website (2005), but retail at 25-50% off as out of production. I don't sell camera equipment - I just write about it!

2007 Ebay sell prices in Australia for 2nd hand Bronica SQ are:

  • SQAi bodies with 80mm lens, back, viewfinder ~$A400-600
  • most lenses $A200-400 ea instead of the $2000-3000 prices when as new in the 1990's.

introduction

  • the Bronica SQ system is a 6×6 modular film system designed for the professional photographer in the 1980's and 1990's.
  • allows TTL flash using Metz flash units with the Bronica SQ adapter if using the SQ Ai camera
  • the lenses have an electronic leaf shutter with flash sync to 1/500th sec
  • unfortunately, the system is now rather redundant as it is quite clunky to use with digital backs, if you can buy a $1000 adapter to achieve this, and whilst the lenses can be used on Canon or Nikon dSLRs via an adapter, there is little if any reason to do so
  • the 6×6 film format uses 120/220 medium format film giving square images (2¼“ × 2¼” or 6cm x 6cm nominally or 56mm x 56mm actual image area)
  • one can buy 645 backs which will allow more photos per roll and give a rectangular 6×4.5cm aspect ratio with the same 120/220 film
  • NOTE that each back is designed for EITHER 120 film or 220 film

image crop factor

  • this 56x56mm film area is 3.6x that of 35mm film and gives a diagonal of 79.2mm which gives a crop factor compared to 35mm film (24mm x 36mm and a diagonal of 43.2mm) of 0.55x
  • thus the popular 150mm f/4 portrait lens on this basis equates to an 83mm f/2.2 lens on a 35mm full frame camera although the aspect ratios will of course differ

using SQ lenses on digital cameras

  • these lenses can be used on other cameras in manual focus and manual stop down aperture mode:
    • if you buy a SQ-Nikon F adapter, you can then get a Nikon-SonyNEX or Nikon-MFT tilt shift adapter and convert it into a tilt shift lens
    • if you are using it on Canon EOS, get an adapter with a Dandelion AF confirm chip to allow manual focus confirmation in the camera
    • to stop the aperture down you have 2 choices:
      • hold the lens DOF preview button down with velcro, or,
      • use T mode on the lens (via Jeff Livacich):
        • Make sure the lens is cocked
        • Pull out on the lock on the the T/A switch on the underside of the lens and move the switch to T (time exposure). To pull the switch out on PS lenses, hook a fingernail under it and pull outward; with the older lenses unscrew it, then pull it out.
        • Look around the edge of the mount from the side of the lens until you see the small metal lock lever projecting from a slot.
        • Push that in, and while holding it in, rotate the two cock/release pins on the back of the lens to the uncocked position. The shutter will close then reopen as you move the pins to the uncocked position.
        • The shutter will stay open until the T/A switch is moved back to A, and the diaphragm will open and close in response to the aperture ring so long as the pins on the back of the lens are in the uncocked position.

Using digital backs:

  • unfortunately few if any digital back manufacturers make a digital back designed for the Bronica system
    • perhaps Leaf Valeo, Leaf Aptus and Leaf Aptus S may be available in Bronica SQ mount
    • perhaps Sinar via Sinarback FW/Bronica SQ-A Adapter Kit (552.65.048)
  • however, you can use many of the digital backs designed for Hasselblad V system as follows:
    • purchase a Bronica SQ to V adapter plate (~$US900)
    • mount the adapter plate via the supplied pin accessory
    • mount a compatible V-type digital back
      • be aware that sensor size will generally be smaller than 6×6 which will limit wide angle capability
      • you may need to test focus accuracy and add a shim to correct any issues
      • generally, you will need a cable from the PC sync to the digital back
      • you will lose exposure metering as the Bronica meter normally gets ISO information from the film back
      • you will not get lens, camera, shutter or aperture in the image EXIF data
  • given the expense and practical difficulties, lack of digital correction and metering, you may be better off getting a Hasselblad instead.

Brief history:

  • 1980: Bronica SQ camera and system introduced with flash sync at all speeds (1/500th sec is fastest speed)
    • it was the 1st 6×6 camera to use a mechanical/electronic leaf shutter lens.
    • it was based on the ETR operating system with a single electronic timer in the body controlling the Seiko #0 shutter in each lens. This provides for maximum accuracy, and consistency of exposures between each lens.
  • 1982: SQ-A camera introduced with refinements including:
    • viewfinder contacts increased from 6 to 10 to allow auto-metering & the new AE finder S.
    • mirror lock up lever added
  • 1983: SQ-Am camera introduced with a built-in motor drive at 2 frames per 3 secs, running on 6xAA batteries
  • 1986: S series lenses gradually replaced by higher quality ones called PS made from the new Bronica factory with world-class facilities which since 1983 had been making the 6×7 camera, the GS-1 and its PG series of lenses.
  • 1990: SQ-Ai camera ($US1661 body only) introduced with refinements including:
    • TTL-OTF flash metering with Metz SCA 386 adapter:
      • used with a Metz SCA flash set on TTL, with camera AE prism meter set to manual (else in low light it will select a long shutter speed)
      • to achieve fill-in flash, increase the ISO setting on the SCA adapter to give under-exposure
      • different films may require compensation to allow for the physical reflectivity of the film surface
    • add-on motor drive (SQ-i) 
    • battery changed to 4×1.5V LR44
    • multi-exposure warning in viewfinder
    • 16 sec calibrated shutter speed & Bulb setting but no longer able to use the mechanical 1/500th shutter speed without batteries.
    • ISO dial on film back relocated to back rather than top where hard to see with prism, & ISO range extended to 6400.
    • new Ai-only winder crank
    • 2005: some retailers new price reductions to clear stock: body only - was $A2130 now $A1650; instant back was $A748 now $A440;
    • kit with 80mm lens, back was $A3545 (2005);
    • see:
  • 1996: SQ-i AE viewfinder added (for SQA/SQAm/SQAi) which added spot metering, LCD display, diopter, 4 stops more sensitivity, exposure lock, blind for long exposures.
  • 1996: “budget” SQ-B camera introduced which was similar to the SQ-A but lacked metering
  • 2004: production of SQ system discontinued

Viewfinders:

  • waist level Finder S with magnifier glass $US249
  • prism finder S $US967
  • 45deg prism finder w/variable diopter $US1020, $A974
  • MF finder S with match LED TTL manual metering & adjustable magnifier from -3 to +2 $US1005
  • ME prism finder S with match LED TTL manual metering $US1322
  • AE prism finder S $US1494, $A1980 - aperture priority auto or manual
  • AE prism finder SQ-i LCD prism finder with spot metering or avg. & AE lock, variable diopter $US1736
    • diopter correction - the +/- closest to eyepiece
    • exposure compensation - the +/- dial at the top giving +/- 2EV
    • dial on right side settings are:
      • A = aperture priority automatic exposure - sets shutter speed according to metering
      • Off = turns light meter off
      • M = manual light metering - user must manually set shutter speed as well as aperture
    • M/C buttons on right:
      • M = memory - holds exposure for 15-30sec - presumably this also allows for mirror lock up capability
      • C = clears previously locked exposure measurement
    • Sp/Av switch on top:
      • Sp = spot metering
      • Av = averaged metering
    • on the under-surface when removed there is a switch with 3 settings:
      • O,1,2 are just meter calibration setting (for if you use an off brand focusing screen for example that's brighter than Bronica's, I suppose). 0 is neutral. 1 is 0.3, 2 is 0.7 - but I forget if it's plus or minus. Just leave it at 0.
    • all that's needed to activate meter properly is having it set to A or M on the side dial, darkslide out, film advanced to frame 1 (or advanced to a stop w/ double exposure lever engaged).
    • LCD in bottom of view should become activated and backlit by green light by half-pressing shutter, this displays:
      • AE or ME for auto vs manual
      • shutter speed (or ERR if light to low or too bright)
      • spot or [] to indicate metering mode
    • the film ASA information is provided by the ASA dial on the film back which acts as a variable resistor:
      • the ASA setting is adjusted by slightly lifting the bottom part of the inner dial & rotating it so the value corresponds with the small arrow marker which at 0EV compensation should be at the 9 o'clock position. If the markers are rubbed off, then the two textured finger areas should be symmetrically placed at 4.30 & 7.30 o'clock position for 0EV.
      • the 12 o'clock mark is the EV compensation & this is changed by holding the lever down while rotating the outer dial
      • the resistance at the two contacts at the top of each film back at 0EV compensation setting should be:
        • 100ASA = 400 ohms
        • 200ASA = 600 ohms
        • 400ASA = 800 ohms
        • 800 ASA = 1000 ohms
        • 1600 ASA = 1200 ohms, etc
    • errors displayed on the LCD screen:
      • flashing 500 usually means you need to close the aperture down, but may be a viewfinder connection problem
      • flashing ERR may occur because the viewfinder's contacts are not sitting properly - adjust the viewfinder.
  • manual finders have 6 contacts, whereas the automatic finders have 10 contacts.
  • SQ auto finders cannot be attached to an SQ body
  • ETR camera finders can be attached to SQ bodies via an adapter plate #1309 but only provide 6×4.5 view.

PS Lenses:

  • introduced starting in 1986 to replace the S series with improvements including:
    • better optics, Multicoated lenses in different groups, elements.
    • better mechanics, Half stop detents, back and front assemblies
    • redesign of the system transmitting the cocking stroke from camera to the shutter, takes care of the “Sloppy Lens Syndrome”
    • redesign of the front assembly eliminated the barrel side screws.
    • addressed light leakages in some lenses
    • removed the vignetting with the 50mm by increasing filter size to 77mm
  • 35mm f/3.5 fisheye with 32.5mm filter $US4440
  • 40mm f/4 95mm filter, $US2718 (equiv. to 23mm f/2.2 in 35mm)
  • 50mm f/3.5 77mm filter, $US2372, $A2310 (equiv. to 28mm f/1.9 in 35mm)
  • 65mm f/4 67mm filter, $US2168 (equiv. to 35mm f/2.2 in 35mm)
  • 80mm f/2.8 67mm filter, $US1660 (equiv. to 45mm f/1.5 in 35mm)
  • 110mm f/4 1:4 macro 67mm filter, close focus 0.6m (equiv. to 60mm f/2.2 in 35mm)
  • 110mm f/4.5 1:1 macro 72mm filter?, close focus 0.37m, $US2159
  • 135mm f/4 67mm filter, close focus 1m, $US2191 (equiv. to 76mm f/2.2 in 35mm)
  • 150mm f/4 67mm filter, close focus 1.5m, $US2372 (equiv. to 85mm f/2.2 in 35mm)
  • 180mm f/4.5 67mm filter, close focus 1m, $US2740 (equiv. to 100mm f/2.5 in 35mm)
  • 200mm f/4 67mm filter, 2.5m close focus $US2531 (equiv. to 110mm f/2.2 in 35mm)
  • 250mm f/5.6 67mm filter, close focus 3m $US2704 (equiv. to 135mm f/3.1 in 35mm)
  • 500mm f/8 $US15688 for flourite PS or $US4229 for S version with 95mm filter (equiv. to 270mm f/4.5 in 35mm)
  • 50-100mm f/4-5.6 with 95mm filter $US2865
  • 1.4x teleconverter $US1307
  • 2x teleconverter $US1277

Older S Lenses:

  • 40mm f/4 82mm filter, 0.4m close focus
  • 50mm f/3.5 67mm filter, 0.5m close focus - some vignetting
  • 80mm f/2.8 67mm filter, 0.8m close focus
  • 105mm f/3.5 67mm filter, 0.85m close focus
  • 150mm f/3.5 67mm filter, 1.5m close focus
  • 200mm f/4.5 67mm filter, 2m close focus
  • 250mm f/5.6 67mm filter, 3m close focus
  • 500mm f/8 95mm filter, 8.5m close focus

Film backs:

  • the film backs are one of the Bronica's weak points as they tend to develop light leaks after years of use.
  • there are several types of film backs:
    • SQ 6×4.5 120 and 220
    • SQ 6×6 120 and 220
    • SQAi 6×4.5 120 and 220 - these have a relocated ASA speed dial
    • SQAi 6×6 120 and 240 - these have a relocated ASA speed dial
    • 135N for 35mm film
      • not sure why anyone would bother with this now that Kodak has stopped making HIE film
    • 135W for 35mm film but in wide panorama format (24x56mm frames)
      • may as well just use 120 backs and crop them
    • Polaroid backs
      • use 3 1/4“ x 4 1/4” film packs but you only get 2 1/2“ x 2 1/2” images
      • Fujifilm are supplying film packs for Polaroid backs:
        • Fuji FP-100B - B&W ISO 100
        • Fuji FP-100C - color ISO 100 - available glossy or silk
        • Fuji FP-3000B - B&W 3000 ISO
      • old Polaroid film versions compatible:
        • 664 - color ISO 100 short exposures (1/10th sec or faster)
        • 665 - B&W ISO 80
        • 667 - B&W ISO 3000
        • 669 - color ISO 80
        • 672 - B&W ISO 400
        • 679 and 690 - color ISO 100 
      • SQ-i version has adjustable ISO values 25-6400 whereas SQ version only has 2 settings - 75 or 3000 ISO. 
      • The Polaroid back also requires that the camera’s multiple exposure lever be engaged for proper operation.
  • using 120 film in 220 backs:
    • there appears to be no focus error issues in using 120 film in Bronica SQ or SQA 220 film backs
    • you can also use 120 inserts in 220 backs
    • there are 2 main problems:
      • film counter issues:
        • is that the camera will assume you can take 24 images as for 220 film in a 6×6 back instead of only 12 for 120 film (30 on a 6×4.5 220 back instead of only 15 frames on 120 film) and thus unless you are alert to this you will end up taking a lot of blank photos - you need to watch the film counter and stop.
        • You'll have to wind the film out and expose until about the 15th frame before opening the back, you'll feel a reduction in tension if hand winding once end of film is reached.
      • where to start the roll so you don't lose the first one or two frames or the last one or two frames:
        • a suggested technique by Budd Gottesman to check frame spacing is the following:
          • “use a test 120 film which you won't develop to mark the spacing of frames
          • load your 120 roll on your 220 insert as usual but bring the arrows to a point approximately 90 degrees (1/4 turn) BEFORE  the start marker on the insert.  
          • Wind the camera to #1 as usual.  
          • Then without a lens on the camera (set to multi-exposure if necessary) fire a shot and mark ON YOUR WASTE ROLL where the frame is located, so when you then remove it (possibly, and I'd recommend) go thru the rest of the roll marking shot by shot, on the film which will assure you how the “SPACING” is working on this back.  
          • BTW: You may need to change the starting point slightly forward/back as you need.  
          • If you give the backs/inserts heavy use, I'd DEFINITELY tell you to check the spacing like this on them all every few months.”

Accessories:

  • speed grip $US416,  $A522
  • motor drive $US1057
  • SCA flash adapter $US340
  • SCA flash bracket $US202
  • professional bellow lens hood $US647
  • focussing screens $US86
  • extension tubes 18, 36mm $US769 ea, $A781
  • bellows $US2670, $A2695
  • film backs $US815 for 120 or 220 backs in either 6×6 or 645 format, or 135N or 135W (24x56mm frames)
  • polaroid back SQ-i 6×6 $US680

 

Batteries:

  • one of the trade offs with Bronica cameras is that you need batteries to take photos as the shutter is electronically timed (most of the SQ series except for SQAi, do allow a fixed 1/500th shutter speed with flat batteries). These cameras have a relatively high amp (~15mA) draw during each shutter release and battery check and thus lithium batteries are not useful.
  • you do not need these batteries if you are using a motor drive as the batteries in the motor drive power the camera.
  • if the shutter release is not working, check that the dark slide has been removed and your batteries are not exhausted
    • if you have put new batteries in and the battery check light does not work then check the battery contacts are clean, the batteries are inserted the correct way, and if still no response, try pushing on the battery pack with the battery compartment lid open and re-check the battery light - if it now lights, you may need to pack the compartment with a little cardboard on the clip side.
    • also, it may be a old speed grip creating contacts which the camera then thinks it is a motor drive and the power source will be coming from the motor drive - remove the speed grip to see if this resolves the problem.
  • for best results, it is recommended to use silver oxide batteries:
    • SQ-A, SQ-B, SQ-Ai: 4 x MS-76
      • NB. using silver oxide in the SQ-Ai with AE finder may cause transient auto exposure errors when the batteries are near exhaustion.
  • alternatively, one can use the cheaper alkaline batteries:
    •   SQ-A, SQ-B, SQ-Ai: 4 x MS-76A
photo/bronicasq.txt · Last modified: 2015/11/02 14:30 by gary1