Hello from the Netherlands and needing advice

J

Jos Segers

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Mar 26, 2021
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I live in the Netherlands and have been active as an amateur photographer for 40 years. Until now I photographed with Pentax 67 cameras. I have my own darkroom.
I am new to this forum and would like to ask your advice.
Recently I purchased a used but spotless Cambo 4x5" monorail technical camera. The equipment has been in storage for about 20 years. Everything seems to be working fine, with the exception of the leafshutters on both included lenses. One shutter is an older type Synchro Compur and the other a Copal 1. Is it true that the shutter speeds of such shutters are by definition inaccurate? A very experienced repairman of analog cameras in the Netherlands told me that especially the Synchro Compur shutters have a bad reputation regarding accuracy of shutter speeds and cannot be adjusted. Deviations in shutter speeds of at least 20% are the rule. Copal shutters on the other hand can apparently be checked and adjusted properly. What is your experience?
 
Welcome.

So long as the shutters are consistent absolute accuracy is not that important (within reason). For example, if you know that the 1/200 speed really is 1/160 you simply adjust exposure accordingly. I have tested many leaf shutters before- and after cleaning and adjustment. Pretty consistently, the top speeds are still somewhat slow. For monochrome, this isn't that big a concern - a slight bit of over exposure isn't a bad thing.
 
Thanks for your advice. I do not have an instrument to measure actual shutter speeds in a direct way. This leads me to the idea of assessing the shutter's behavior at common shutter speeds using an exposure sequence. The 4x5 set comes with a 6x7 backing for 120 film and I happen to have a densitometer that I normally use for making density curves of film-developer combinations. It is mainly a practical way but does give an indication of the shutter's behavior. At least that's what I expect.
 
Hello Jos and welcome. Your experience with large format may prove different to mine, but with 5x4 and 7x5 cameras I find that I rarely use a shutter speed faster than 1/4 second. Most of my exposures seem to be at 1/4 (or 1/5th) 1/2, 1second, or longer. So maybe you don't need to worry too much about checking the accuracy of the faster speeds.

Alan
 
Thank you Alan. Good to know. So then I don't have to worry about the faster shutter speeds. In any case I will have the Copal 1 shutter serviced. After tensioning it jumps back immediately. This is hopefully repairable.

Jos
 
20% is a fifth of a stop. Not as much as it first sounds. As has been mentioned, it doesn’t matter what the actual speed might be, as long as you know what gives you a decent, workable negative. If you’re exposing B+W film, quite large excursions from “correct” exposure are easily accommodated in printing. There is plenty of advice on this forum for developing in ways that give greater control over the negative.
Your densitometer method would show which speeds were faster or slower than standard, but not which which ones were correct. This assumes that your aperture stops down accurately, of course.
Transparencies are a different matter.
When there were gramophone turntables, you could use one to give an idea of shutter speed. Any other device with predictable motion might be pressed into service instead.
It’s wise to have shutters serviced, as we need to preserve this threatened species.
 
Thank you for your tips David.

I have no practical experience of developing 4x5" negatives so suggestions are welcome. Basically, I am looking for a method that fits with developing FP4+ in Pyrogallol. This combination is the best possible match for the kind of subjects I shoot and the specific image quality I am looking for. It would be nice if members of this forum have suggestions for a development method that minimizes the risk of uneven development. Ideally, because of the toxicity of Pyrogallol, I would like to stick to the method I have been using for years for developing roll films. Until now, I have had consistent results with a Patterson tank. I use a tank with a larger capacity so that the developer has enough room to flow freely along the film during the tipping process. Is something similar conceivable for 4x5 negatives?
 
This is how I do it with Pyrocat-HD. It's not the only way. Everyone has their own approach. However, I find this approach very forgiving so long as the shadows are well exposed. You do need to wear nitrile gloves and eye/clothing protection when doing this, but you should be doing this with any version of Pyro. (I have not had similar results with 510 Pyro, and PMK Pyro cannot be used this way because of its considerable oxidation rate):

gitbucket.tundraware.com

tundra/Stand-Development

gitbucket.tundraware.com gitbucket.tundraware.com

P.S. As the article suggests, if you decide to try this, do not use a Patterson tank for this, only minimal support pinch hangers and an open tank. I tried doing this in a Yankee tank and got bromide drag-induced disaster. I am guessing that the Patterson also has very large ridges of support, hence I'd avoid it.

EDIT: I stand corrected, I did not quite understand how the Paterson tank was configured. The pinch hanger suspension for the method above likely wouldn't work with this tank. The "taco" method described below might.
 
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Jos Segers said:
Until now, I have had consistent results with a Patterson tank. I use a tank with a larger capacity so that the developer has enough room to flow freely along the film during the tipping process. Is something similar conceivable for 4x5 negatives?
Click to expand...

There are sheet holders that can be used for developing 4x5 sheet film in a suitable Paterson tank. Alternatively, Taco method with hairbands/rubberbands can be put to service without spending money on such holders if you already have the tank. Here are some pics, not by me, that help understand the method:
www.flickr.com

4x5 Taco Method for Patterson Tank

The "taco method" for developing 4x5 sheet film in standard tanks has been around for a while. Here's how I do it using the Patterson Super System 4 developing tank (available from lots of places, including Freestyle www.freestylephoto.biz/11516-Paterson-Universal-Film-Deve...). This method...
www.flickr.com www.flickr.com

However, I use two rubber bands per sheet, one each at approximately 1/3rd distance from the two corners and I prefer using three tacos at a time even if I am developing one two sheets (which means some scrap sheets are needed but can be reused). I also roll the bands up/down a little once during fixing and washing steps which prevents the bands from leaving marks on the shiny side of the sheet. I prefer to do continuous agitation by rolling the tank slowly on a counter top but standard intermittent inversion agitation can also be used.
 
The ISO standard covering shutters is the shutter speed should be +/- 30% of the marked speed, usually they are very much closer.

You can record the shutters slow speeds and get a good idea of the accuracy by checking the timeline with Audacity. This is a 1913 Dial set Compur. The first speed is 1 second, then 1/2, 1/5,1/10 etc.

Ian
 
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David M said:
20% is a fifth of a stop. Not as much as it first sounds
Click to expand...

Doesn't quite work like that as 50% lower is a complete stop, and 100% faster is a complete stop.

If we take a shutter speed of 1/60 then 20% slower is 1/50, which is a third of a stop, and 20% faster is 1/75 which is around a quarter of a stop faster, a third is 1/80.

Ian
 
Raghu Kuvempunagar said:
There are sheet holders that can be used for developing 4x5 sheet film in a suitable Paterson tank. Alternatively, Taco method with hairbands/rubberbands can be put to service without spending money on such holders if you already have the tank. Here are some pics, not by me, that help understand the method:
www.flickr.com

4x5 Taco Method for Patterson Tank

The "taco method" for developing 4x5 sheet film in standard tanks has been around for a while. Here's how I do it using the Patterson Super System 4 developing tank (available from lots of places, including Freestyle www.freestylephoto.biz/11516-Paterson-Universal-Film-Deve...). This method...
www.flickr.com www.flickr.com

However, I use two rubber bands per sheet, one each at approximately 1/3rd distance from the two corners and I prefer using three tacos at a time even if I am developing one two sheets (which means some scrap sheets are needed but can be reused). I also roll the bands up/down a little once during fixing and washing steps which prevents the bands from leaving marks on the shiny side of the sheet. I prefer to do continuous agitation by rolling the tank slowly on a counter top but standard intermittent inversion agitation can also be used.
Click to expand...

Are you using this for conventional development/agitation methods or have you found this be successful with low agitation/long duration approaches?
 
David M said:
20% is a fifth of a stop. Not as much as it first sounds. As has been mentioned, it doesn’t matter what the actual speed might be, as long as you know what gives you a decent, workable negative. If you’re exposing B+W film, quite large excursions from “correct” exposure are easily accommodated in printing. There is plenty of advice on this forum for developing in ways that give greater control over the negative.
Your densitometer method would show which speeds were faster or slower than standard, but not which which ones were correct. This assumes that your aperture stops down accurately, of course.
Transparencies are a different matter.
When there were gramophone turntables, you could use one to give an idea of shutter speed. Any other device with predictable motion might be pressed into service instead.
It’s wise to have shutters serviced, as we need to preserve this threatened species.
Click to expand...

As noted elsewhere, that's not quite how f/stop deviation is calculated. For the mathematically inclined, this requires logarithmic calculations in base 2. As I recall (someone correct me if I am wrong) the formula is:

Code: 
                             log(measured speed/nominal speed)
    deviation in f/stops =   ----------------------------------
                                        log 2


                              where "log" is base 10

So, a 20% deviation of speed, is about 0.32 stops variation.
 
Very much better maths than mine. Thank you. Can we meter a normal feral scene to within a third of a stop, anyway? Two photographers at the same scene might give exposures that differ by more than this, depending on their own preferences. If they were members of this forum, we’d expect both of them to deliver excellent prints.
My point was that it’s not as big a problem as first appears. Unreliability would be much worse, as everyone has mentioned.

Thank you for the Audacity tip. Excellent idea.
 
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David M said:
Very much better maths than mine. Thank you. Can we meter a normal feral scene to within a third of a stop, anyway? Two photographers at the same scene might give exposures that differ by more than this, depending on their own preferences. If they were members of this forum, we’d expect both of them to deliver excellent prints.
My point was that it’s as big a problem as first appears. Unreliability would be much worse, as everyone has mentioned.

Thank you for the Audacity tip. Excellent idea.
Click to expand...

Having tested dozens of shutters, both leaf and focal plane, I can say with some confidence that - if a shutter is generally working well - speed problems typically manifest themselves at the higher speeds and show slowness. This translates into more exposure. The latitude of modern monochrome films can easily accommodate a bit of overexposure. For very slow shutters, one just keeps a note of how slow and adjust the exposure accordingly. This works about 90% of the time when the shutters are sluggish but consistently so. For shutters that vary considerably, it's time for an overhaul.

Contrary to popular belief, the primary reason for shutter inaccuracy isn't a lack of lubrication, and may even be caused by over lubrication. I have "fixed" a great many leaf shutters, especially, simply by cleaning them with a slight application of naptha to remove the years of accumulated grime. For really bad actors I send them out for cleaning and adjustment by a professional, of course. Some older leaf shutters like Ilex/Acme, actually make this very easy to do. One removes the lens elements and then takes off the front plate and voila' the guts of the shutter train/gears are exposed for that gentle application of naptha for cleaning and healing.

I do keep records of every shutter in my stable so I can refer to how bad the error is if I need to. With 5x4 lenses, I a most typically shooting at the lower speeds which tend to pretty much be right on.

Can we meter a normally feral scene within a third of stop? Yes, if we're careful to calibrate in the first place. There are times - say with very big SBRs - that I want to nail Zone III within that margin so I can maximize the available range of the film for the brighter zones. I have also done side-by-side comparisons of 1/3 stop increments and have seen meaningful differences. Fortunately, this isn't often that critical, especially the way I now process film most of the time, so 1/3-1/2 stop variation isn't of much concern these days.

I do not recall the reference to Audacity. You'll have to refresh my memory.
 
Some years ago on an APUG/Photrio long weekend in Cornwall three of us sat on the grass overlooking The Crowns at Bottalak.

We were all using different meters, I had my Pentax Spotmeter V of the , also a Gossen Luna Pro, someone had a Sekonic, can't remember the other or the models. As an exercise we all independently metered the shot of The Crowns engine houses. What was surprising was we were all within a third of a stop of the same exposure.

With B&W 1/3 of a stop difference is generally insignificant, except where there's a long tonal range with important shadow details. However with E6 1/3 of a stop can be far more critical.

But back to the OP's question most leaf shutters are remarkably accurate, when I check the slow speeds of a number of shutters the variations were more like +/- 5% of the marked speed. The highest speed is always the least accurate (typically slower) but in general the lens is then usually at a wider aperture and the leaf shutter, because of the way it opens and closes, also acts like an aperture, compensation slightly. It's this aperture effect that limits the higher speeds of large shutters like the Copal #3 to 1/125, and the Compound #3 to 1/100. Larger shutters like the Betax and Alphax #4 and #5 , also the Compound #5, have a 1/50 top speed.

As films became faster in the mid to late 1920s, which accelerated in the mid 1930s in Europe* higher top speeds became more important, because of the limitations of leaf shutters some of the more professional German 9x12 cameras offered dual shutters. An example is the 9x12 Ihagee Zweiverschluss Duplex, a press camera with a 135 f3.5 CZJ Tessar in a dial set Compur #2 shutter, top speed 1/200, and also a Focal Plane shutter for speeds to 1/1000.

This was not a new idea Thornton Pickard produced a Dual shuttered Thornton Pickard Imperial half plate camera, with a Focal plane shutter, as well as a between lens shutter, top speed 1/1000, and you could also add an extension shutter. I have two, and an Imperial with Dual shutters, all to restore.

Going back to the aperture effects of high leaf shutter speeds this gets greater as you open up the f stops. However, LF lenses are optimised for f22. Then how often can you get close to using the fastest speeds, when shooting hand held in Turkey I can just get to f22 @ 1/200 or 1/250 depending on the lens/shutter with HP5


* the comment is based on how much more advance Ilford and Agfa were in terms of film technology in the 1930's compared to Kodak.
Selochrome Fine Grain Pan (FP) and Ilford Hypersensitive Pan (HP) were introduced in 1934, Kodak fired back in 1939 with their Pan X to Tri-X range, but by then Ilford had already released FP2 and HP2, and then FP3 and HP3 in 1941. Agfa were equally as advanced.

Ian
 
Ian Grant said:
Some years ago on an APUG/Photrio long weekend in Cornwall three of us sat on the grass overlooking The Crowns at Bottalak.

We were all using different meters, I had my Pentax Spotmeter V of the , also a Gossen Luna Pro, someone had a Sekonic, can't remember the other or the models. As an exercise we all independently metered the shot of The Crowns engine houses. What was surprising was we were all within a third of a stop of the same exposure.

With B&W 1/3 of a stop difference is generally insignificant, except where there's a long tonal range with important shadow details. However with E6 1/3 of a stop can be far more critical.

But back to the OP's question most leaf shutters are remarkably accurate, when I check the slow speeds of a number of shutters the variations were more like +/- 5% of the marked speed. The highest speed is always the least accurate (typically slower) but in general the lens is then usually at a wider aperture and the leaf shutter, because of the way it opens and closes, also acts like an aperture, compensation slightly. It's this aperture effect that limits the higher speeds of large shutters like the Copal #3 to 1/125, and the Compound #3 to 1/100. Larger shutters like the Betax and Alphax #4 and #5 , also the Compound #5, have a 1/50 top speed.

As films became faster in the mid to late 1920s, which accelerated in the mid 1930s in Europe* higher top speeds became more important, because of the limitations of leaf shutters some of the more professional German 9x12 cameras offered dual shutters. An example is the 9x12 Ihagee Zweiverschluss Duplex, a press camera with a 135 f3.5 CZJ Tessar in a dial set Compur #2 shutter, top speed 1/200, and also a Focal Plane shutter for speeds to 1/1000.

This was not a new idea Thornton Pickard produced a Dual shuttered Thornton Pickard Imperial half plate camera, with a Focal plane shutter, as well as a between lens shutter, top speed 1/1000, and you could also add an extension shutter. I have two, and an Imperial with Dual shutters, all to restore.

Going back to the aperture effects of high leaf shutter speeds this gets greater as you open up the f stops. However, LF lenses are optimised for f22. Then how often can you get close to using the fastest speeds, when shooting hand held in Turkey I can just get to f22 @ 1/200 or 1/250 depending on the lens/shutter with HP5


* the comment is based on how much more advance Ilford and Agfa were in terms of film technology in the 1930's compared to Kodak.
Selochrome Fine Grain Pan (FP) and Ilford Hypersensitive Pan (HP) were introduced in 1934, Kodak fired back in 1939 with their Pan X to Tri-X range, but by then Ilford had already released FP2 and HP2, and then FP3 and HP3 in 1941. Agfa were equally as advanced.

Ian
Click to expand...

If I'm not mistaken, lab quality shutter speed testers (as opposed to the simple timer I have) actually integrate the total amount of light during the exposure. For all the reasons you cite, the simple timer yields misleading results.
 
You can't use a simple timer to effectively test high shutter speeds for this aperture reason. And then shutter repairers don't do lab tests of a shutter at its higher speeds across a lens' full aperture range.

Ian
 
Your detailed explanation of how leafshutters work is very inspiring. Thank you all very much for diving so deeply into the subject.
So far, I have been lucky with my SLRs (Pentax LX, ME Super, MX, 67II). That means predictable shutter speeds and ditto exposures. After developing and drying the film I visually check the negatives I want to print on a light table. Even minor deviations from the correct density are visible this way. I check contrast with a densitometer. I now understand from your experiences that I will have to redesign and calibrate my process of exposing, developing and printing with large format photography. A nice challenge for which your advice is very welcome.
 
Jos Segers said:
A very experienced repairman of analog cameras in the Netherlands told me that especially the Synchro Compur shutters have a bad reputation regarding accuracy of shutter speeds and cannot be adjusted.
Click to expand...

This doesn't sound right to me. Indeed I've heard assertions that the mechanics of the Compur shutter were superior to those of the Copal shutter. (Though if this is the case I've not seen any evidence that it makes a difference in the "real world") I have a number of lenses in both Compur and Copal shutters. The Compur shutters vary in age from roughly 90 year-old dial-sets to No. 1 Compurs with a top-speed of 1/500 which are probably from the last years of production. In general the Compurs (and the Copals) are reasonably accurate and rather consistent. From time-to-time they will need a visit to the repairman.

A few years ago I bought a shutter speed tester from a seller on the American ebay with the name "vfmoto". This seller is in Romania and is currently quite active with a number of offerings.

The importance of consistency has been well covered already.

David
 
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