Film Holder Review: Sinar Zoom
Introduction
I have not used my Intrepid 4x5 camera in quite a while. In my first use I tried our my MPP 6x9 film holder. Film holders of this type allow one to use 120/220 roll film with a large format camera. They are often referred to as ‘international’ or Graflok backs. They come in a number of fixed sizes such as 6x7, 6x8, 6x9, up to 6x12. 6x12 is the upper limit as 12 cm is the same as 5 inches the length of 4x5 film. (There are some more specialised 6x17 as well for the 3:1 aspect ratio. These work with their own ground glass and extend slightly beyond the normal film plane to achieve the greater than 12 cm film length.)
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| MPP 6x9 Film Back |
These roll film holders usually require the ground glass to be removed owing to the thickness of the film back. This makes for some extra steps that goes like this. 1) Focus and compose on the ground glass (taking into account the smaller film format). 2) remove the ground glass, 3) place film back in place, 4) remove dark slide, 5) make exposure, 6) replace dark slide, 7) remove film back, 8) replace ground glass.
Roll film has some advantages in these cases as it is somewhat cheaper and film handling is easier than sheet film. It is certainly true however that staying with sheet film one can achieve whatever crop you wish. Another way of thinking about the utility of film backs is to look at it the other way around. It enables you to add movements to your medium format pictures. One can correct for verticals or make sure foreground and background are in better focus with the movements available on a large format camera.
I have toyed with the idea of getting a 6x17 back but they are big and expensive. (Nick Carver is a big fan and regular user of a 6x17 film back.) I already have a Fuji G617 which I love so this seemed like an extravagant expense. (Tempting none-the-less as my Fuji has a fixed 90mm lens and the back would enable me too use different lenses.)
I was looking at some recent videos by Steve O’nions where he used an Intrepid 4x5 with a film back. He used a 6x12 back (a very nice Horseman I believe). I like the wider format compared to the 6x9 I have so I started to look around on eBay for a 6x12 film back. I had my eye on the Horseman as it looked very well made (about £360 at this time).
The MPP 6x9 film back I have is a bit rough and stiff to use when loading and advancing the film. I could also see some Dayi and Shen Hao Chinese versions that offer multiple frame formats such as 6x4.5, 6x6, 6x9 as well as 6x12. These are about £100 cheaper than the Horseman. They are simpler designs using the red window and the numbers on the back of the film backing paper. I find these frame numbers difficult to read and prefer film backs that automatically index to each frame like my MPP 6x9 film back.
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| Horseman 6x12 Film Back |
The MPP 6x9 film back I have is a bit rough and stiff to use when loading and advancing the film. I could also see some Dayi and Shen Hao Chinese versions that offer multiple frame formats such as 6x4.5, 6x6, 6x9 as well as 6x12. These are about £100 cheaper than the Horseman. They are simpler designs using the red window and the numbers on the back of the film backing paper. I find these frame numbers difficult to read and prefer film backs that automatically index to each frame like my MPP 6x9 film back.
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| Guohua 6x12 Film Back from China |
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| Dayi 6x12 Film Back (note masks needed to change frame size) |
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| Shen Hao 6x12 Film Back |
While perusing these offerings I stumbled upon a different kind of film back. SINAR the Swiss maker of fine and innovative large format cameras made a series of film backs that were a little different. First of all they fit into the camera like a normal sheet film holder. No removal of the ground glass is required. They work by running the film across the film plane then back 180 degrees in a loop to the take-up spool. This all happens in a thickness a little more than a sheet film holder about 1” (25mm).
Some cameras cannot accommodate this thickness but fortunately it works in the Intrepid MkIII. (These backs can also be used like other backs using the Graflok with the ground glass removed however. The Zoom 2 cannot however as it lacks the slots the Graflok requires.)
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| Film Path of Zoom. Film plane at bottom. Take-up spool on top. |
Some cameras cannot accommodate this thickness but fortunately it works in the Intrepid MkIII. (These backs can also be used like other backs using the Graflok with the ground glass removed however. The Zoom 2 cannot however as it lacks the slots the Graflok requires.)
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| SINAR Zoom 6x12+ Film Back |
There are a number of different varieties of from SINAR
SINAR 67 — A fixed 6x7 frame
SINAR 69 — A fixed 6x9 frame
SINAR Vario — Similar to the zoom but can’t change frame size mid-roll
SINAR Zoom — The one I describe here
SINAR Panorama — A fixed 6x12 frame
SINAR Zoom 2 — A newer model of the Zoom with a conventional dark slide and no Graflock slots.
I was able to get a SINAR Zoom for about £245. (These were $3000 in the US and $1800 in Europe new.) The Zoom offers a variable set of formats of 6x4.5, 6x6, 6x7, 6x9, 6x12. It is possible to change the formats on-the-fly (within the same roll) giving a good level versatility within one film back. I anticipate that I will stay with the 6x12 size but the extra formats could come in handy and the fact I don’t have to remove the ground glass I anticipate to be a handy feature.
I have looked at various comments and reviews on the trade-offs on the Zoom vs other 6x12 film backs like the Horseman. I note the experiences were in line with the benefits outlined above. The SINAR Zoom is 972 grams which is heavy enough I might not take it on a long hike or backpacking. (The Horseman 6x12 is reported to be about 600 grams.)
Some comments were made about the complexity of film loading compared to conventional film backs. I too was concerned about this but it doesn’t seem as challenging a I thought. How I fare in the field may be another matter.
Some comments were made about the complexity of film loading compared to conventional film backs. I too was concerned about this but it doesn’t seem as challenging a I thought. How I fare in the field may be another matter.
There was speculation the weight and bulk might be a challenge with lighter 4x5 cameras (I suppose like the Intrepid) in that the focus might change or shift once it is inserted. I couldn’t find anyone who had written about the SINAR Zoom with the Intrepid so I will report on this aspect later.
There were some claims the film flatness would be superior given the film path. There seemed to be no consensus on this and other backs did not seem to present a problem.
Features of the SINAR Zoom
In addition to the variety of formats the film back keeps track of the film used and prevents double exposure or accidental exposure. There is a small safety pin that keeps the dark slide shutters from being opened unless the film back is placed in the camera. Another pair of small locking pins prevents the removal of the film back from the camera if the dark slide shutters are open. I was pleased the interlock pins engage already-made slots in the Intrepid so there was no need to modify the camera to enable this feature.
You can get the following number of images according to the frame size on a roll of 120 film. Double these numbers for 220 film.
6x4.5 — 16 images
6x6 — 12 images
6x7 — 10 images
6x9 — 8 images
6x12 — 6 images
Since frame sizes can be changed within the roll it is difficult to have a conventional frame count where the frame size changes.
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| Explanation of the parts of the roll film holder. |
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| The film holder. |
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| Film path |
Film Loading
Film loading is necessarily more complex as this film path is more convoluted. I however found it straightforward. Certainly easier than loading sheet film in a dark bag. Not much worse than most medium format cameras. There is is a separate film cartridge where the film spool and take-up spool are held. Once this is loaded and the take-up spool is in place it can be placed into the film back with a small leader of backing paper protruding. This is then threaded under a roller, along the film plane then under a second roller at the end of the film plane where emerges to run back across itself to the take-up roll. At the end of the film back where it emerges are the arrows to line up with the start roll arrows on the backing paper. The end is then threaded into the take-up roll and made taught. The cover is them locked into place.
Next the film advance lever is moved until the film progress window shows EXP. Then a lever on the side is moved from LOAD to EXP which engages the film metering system. It is now ready to use.
Making an Exposure
Once the image is composed and focused on the ground glass the film back is inserted like a normal sheet film holder (DDS). The Vario and Zoom models do not have a conventional dark slide. Rather there are overlapping masks that are opened in accordance the desired image format like 6x6 or 6x12. With the shutter closed a knob is rotated to open these masks. The masks open according to the size for frame selected.
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| Overlapping masks in closed position. |
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| Overlapping masks in 6x4.5 frame format. |
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| Overlapping masks in 6x9 frame format. |
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| Overlapping masks in 6x12 frame format. |
Now the shutter can be released. The film is advanced by pressing the Reset button and the film advance lever is actuated until it stops. The masking knob is rotated in the opposite direction to close the masks which is like inserting the dark slide.
The Zoom model lacks a frame counter as it is impossible to show remaining frames when the size of frames is variable. Rather the frame counting window shows how much film is left in cm. There are two sets of numbers one for 120 film the other for 220.
It is possible to change frame sizes for each image. After the film is advanced the reset button can be pressed again and the frame size knob rotated to select the desired frame size. This can be somewhat wasteful but it does a pretty good job of spacing the images. It is a remarkable mechanism for this capability.
To aid in composition SINAR provides a ground glass mask that fits the Intrepid ground glass. This mask can be adjusted for the frame size to aid composition on the ground glass for the smaller film size. I will need to make a clip to hold it in place on the Intrepid. This shouldn’t be too challenging. Sliding the knob at the upper right moves both yellow frames in unison to make a frame of the corresponding size.
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| Viewscreen mask for composing different frame formats on ground glass. |
In the film gate of the film back are two small transparent windows that can be replaced with a customised lith film. The purpose of these is to enable someone to make small copyright notices or photographer names. Once in place they will imprint the film edge where the frame number and film maker indications are with a name or copyright. I really like this attention to detail.
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| Copyright imprinting films. |
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| Copyright imprinting film along edge of film gate. |
So far I am pleased with the purchase. I have yet to try it in the field but will do so at the next opportunity and report back my results and impressions.
I preloaded the film back with Ilford PANF+ before I went out. I only had time for one roll of film so I did not try and field load it.
The Zoom fits into the the Intrepid Mk3 4x5 well with some care. My Intrepid spring back has a problem where it can come loose from one pin if stretched too far. This means I have to be extra careful loading the Zoom back into it.
Composition
I had not gotten around to making a retention clip for the composition insert. This was a mistake and I will need to correct this before I go out again. The result is the insert falls out readily while checking focus when there is not another hand available.
Update:
I did finally make some small plastic clips to hold the composition insert. Simple pieces of scrap plastic cut out and screwed into the wood frame.
Loading the Zoom back into the Intrepid
I always use the Graflock clips option as extra support. It also helps to confirm the Zoom back is properly positioned. There is a little ramp on the Zoom back where the film holder is inserted. This means the spring back (ground glass holder) is angled up. Awkward but not actually a functional problem. It can make one unsure the holder is in the right place. I had no light leaks however.
Update: Modifications to Intrepid Ground Glass Holder
As mentioned in the previous paragraph the end of the ground glass holder angles up and doesn't fit well against a little 'ramp' on the back of the SINAR. I decided to resolve this by modifying the ground glass holder. On the right edge I carefully cut a matching ramp in the plywood of the ground glass holder. I also had to file some of the black metal plate that is used to lift the ground glass holder when loading film backs. This is because there are two latches on the back of the SINAR that begin to interfere once the ramps are cut.
Below are the details of the change. The SINAR Zoom now loads much easier now and does not feel as precarious. Operation with normal film backs is unaffected.
Weight
The biggest concern I had with the Zoom back is its weight. Would the Intrepid hold up? I found generally it did but not without some effect/concern. The worst case is landscape mode where the offset weight of the film holder wants to drag the camera to the right. Once inserted there is a very small tilt noticed. Careful attention to the spirit level can help here. That being said I did not see any terrible change in the final images. Focus was also unaffected. There is a small tendency for the rotating back to rotate slightly that one might have to move back so it is important to lookout for.
Update: First Field Impressions
I made it out the other day and got to try the SINAR in the field. These are my impressions.I preloaded the film back with Ilford PANF+ before I went out. I only had time for one roll of film so I did not try and field load it.
The Zoom fits into the the Intrepid Mk3 4x5 well with some care. My Intrepid spring back has a problem where it can come loose from one pin if stretched too far. This means I have to be extra careful loading the Zoom back into it.
Composition
I had not gotten around to making a retention clip for the composition insert. This was a mistake and I will need to correct this before I go out again. The result is the insert falls out readily while checking focus when there is not another hand available.
Update:
I did finally make some small plastic clips to hold the composition insert. Simple pieces of scrap plastic cut out and screwed into the wood frame.
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| Intrepid Ground Glass and New Clips |
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| with SINAR Composition Frame in place. |
I always use the Graflock clips option as extra support. It also helps to confirm the Zoom back is properly positioned. There is a little ramp on the Zoom back where the film holder is inserted. This means the spring back (ground glass holder) is angled up. Awkward but not actually a functional problem. It can make one unsure the holder is in the right place. I had no light leaks however.
Update: Modifications to Intrepid Ground Glass Holder
As mentioned in the previous paragraph the end of the ground glass holder angles up and doesn't fit well against a little 'ramp' on the back of the SINAR. I decided to resolve this by modifying the ground glass holder. On the right edge I carefully cut a matching ramp in the plywood of the ground glass holder. I also had to file some of the black metal plate that is used to lift the ground glass holder when loading film backs. This is because there are two latches on the back of the SINAR that begin to interfere once the ramps are cut.
Below are the details of the change. The SINAR Zoom now loads much easier now and does not feel as precarious. Operation with normal film backs is unaffected.
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| Back of Ground Glass Holder |
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| Front of Ground Glass Holder |
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| Side View with SINAR in Place |
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| Top View with SINAR in Place (Note latches and notches to accommodate) |
Weight
The biggest concern I had with the Zoom back is its weight. Would the Intrepid hold up? I found generally it did but not without some effect/concern. The worst case is landscape mode where the offset weight of the film holder wants to drag the camera to the right. Once inserted there is a very small tilt noticed. Careful attention to the spirit level can help here. That being said I did not see any terrible change in the final images. Focus was also unaffected. There is a small tendency for the rotating back to rotate slightly that one might have to move back so it is important to lookout for.
Update: A Fix for Rotating Back Problem in Landscape Mode
As mentioned above there is a tendency for the offset weight of the filmholder to slightly rotate the rotating back when in landscape position. This can be annoying to remember to check this position. It is a problem if the film back rotates slightly as the wide format is not very forgiving of tilt and cropping to fix the problem can ruin the compostion. To remedy this I made another small modication. I made a small wood tab that I screwed into the bottom of the rear standard. It is dimensioned so in one position it won't interfere with the rotating back yet when flipped out it will hold the back square with the camera. It can work in both landscape and portrait orientation though I only anticipate its use in landscape orientation. Photos of it are shown below.
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| This shows the tab in the position that allows rotation of the back. |
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| Here the tab is swung into the lock position so the rotating back will not shift. |
Errors
Since the dark slide is actually a knob that needs to be rotated it is not part of the normal film process and this resulted in one ruined image.
Overall
I enjoyed using it. It is a little more fussy than a double dark slide film holder but not annoyingly so. I think with practice the experience will only get better. I like the 6x12 format as much as I thought I would.
Since the dark slide is actually a knob that needs to be rotated it is not part of the normal film process and this resulted in one ruined image.
Overall
I enjoyed using it. It is a little more fussy than a double dark slide film holder but not annoyingly so. I think with practice the experience will only get better. I like the 6x12 format as much as I thought I would.
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