Hasselblad leaf shutter problem

[Thomas Bertilsson]

Hi,

I just acquired a Sonnar 150mm for my 500C, and it appears the shutter is sticky on it. When I asked a question about it, it appears as though the leaf shutter, by design, is almost never functioning properly, kind of like reciprocity failure in film.

1. My lens causes severe overexposure, about 3 stops worth, in cold weather. Indoors when the lens is warm it's more like 1-1.5 stops.

2. How does this leaf shutter design really work? What causes it to be a notoriously bad design, especially in cold weather? (That's how it was explained to me, not my opinion).

I guess I'm surprised, because my 80mm Planar works like a champ in any weather, and it's got a LOT more wear and tear on it than the Sonnar. And the other thing that baffles me is that a company like Hasselblad could allow a flawed design, that's the part that really doesn't make sense to me.

Thank you kindly for your advice. I really need to understand what this problem is.

- Thomas

 

[chriscrawfordphoto]

You were lied to. I use my Hasselblad in subzero temperatures all the time with NO problems. The shutter needs relubed and cleaned. This costs about $150 so I hope the lens was cheap.

 

[Thomas Wilson]

Thomas, a "Sticky shutter" is not the end of the world. A CLA (clean, lube & adjustment) should take care of your problem. I have a 150 C that gets a little sluggish below 1/15th. I will bite the bullet and buy a CF version very soon. I hate the idea of putting $150.00-$200.00 into a lens for which a very limited supply of spare parts are available.

Once your lens is back in your possession, be sure to exercise it by running it through all of the shutter speeds once in a while. This will help prevent the lubricant from thickening and slowing things down.

"Hasselblad... flawed design?" I don't think so!

 

[Anscojohn]

Well, a sticky shutter is one thing; and a sticky aperture is another thing. That being said, it has long been a known? fact that at 1/500 second, at f/16, you are going to get virtually the same exposure with a leaf shutter as you would get at 1/250. The way it was explained to me, it has to do with the ineritia at the very beginning of the shutter movement combined with the small areas which the shutter uncovers at the smallest f/stops. This "problem" disappears at wider apertures.

 

[Claire Senft]

Back in the seventies I would go out in very cold weather with my Hsselblad which had lenses with "c" ...Compur...80mm Planar 60mm 4.0 Distagon and 150mm Sonnar. It was not unusal to have a shutter develop a problem with the very cold weather...stick open or run very slow. In those days the fix was $45-$50 at a local camera service. Hasselblad offered a lubing service for severe cold. I did not like pay the $50 for repair and I did not like sending the lenses to New Jersey for special lubing either. This was the only problem I had with my Hasselblad. I do not know if the modern shutters are improved in this respect or not.

 

[chriscrawfordphoto]

My Hassy lenses are all the CF lenseswith the improved Prontor shutters. They've never given problems in cold. If the OP wants to get his serviced, I recommend David Odess, he is working on one of my lenses that had a spring break. He's a retired Hasselblad tech, factory trained.

 

[Ed Sukach]

... That being said, it has long been a known? fact that at 1/500 second, at f/16, you are going to get virtually the same exposure with a leaf shutter as you would get at 1/250. The way it was explained to me, it has to do with the ineritia at the very beginning of the shutter movement combined with the small areas which the shutter uncovers at the smallest f/stops.

... And you believed the guy that gave you the "known fact" (note 1) explanation?

There ARE tolerances placed upon shutter speeds, usually by the manufacturers themselves, but they tend to be "buried" in a mountain of other design parameters - look at it this way... why would ANYONE consider a tolerance approaching 100% (1/500th actually exposing the film for ~1/250th second) EVER be considered "good"?

There are volumes of maintenance problems that could/ would slow a shutter down at any speed. MAINTENANCE problems - not DESIGN.


Note 1) Whenever I encounter the words, "known fact", a red flag goes up: probably ... most likely... NOT TRUE.

 

[chriscrawfordphoto]

... And you believed the guy that gave you the "known fact" (note 1) explanation?

There ARE tolerances placed upon shutter speeds, usually by the manufacturers themselves, but they tend to be "buried" in a mountain of other design parameters - look at it this way... why would ANYONE consider a tolerance approaching 100% (1/500th actually exposing the film for ~1/250th second) EVER be considered "good"?

There are volumes of maintenance problems that could/ would slow a shutter down at any speed. MAINTENANCE problems - not DESIGN.


Note 1) Whenever I encounter the words, "known fact", a red flag goes up: probably ... most likely... NOT TRUE.

He is actually right about leaf shutters overexposing at high speeds and small apertures. It is because the timing starts when the blades reach the fully open position, but when you shoot with a small aperture, the small hole is fully uncovered long before the blades reach the full open position, and as the blades close it takes a short time for the blades to close enough to cover up the small opening you have at a small aperture.

 

[Thomas Bertilsson]

Well, it is a C lens, a T*, came in its original packaging with virtually NO sign of use since purchased. The only giveaway is the paint scraped away at the filter mount. I have no idea what the lens cost, as it was a gift from someone who really cares about me.

Could the culprit be too little use? From what I understand, the original (only) owner hadn't used it for the last 15 years or so, and sparingly prior to that.

Thanks so far for your wonderful advice!

- Thomas

 

[Anscojohn]

He is actually right about leaf shutters overexposing at high speeds and small apertures. It is because the timing starts when the blades reach the fully open position, but when you shoot with a small aperture, the small hole is fully uncovered long before the blades reach the full open position, and as the blades close it takes a short time for the blades to close enough to cover up the small opening you have at a small aperture.

&&&&
That is the way I understand it. Thanks for explaining it better than I could.

 

[Q.G.]

That's not quite right.
The exposure begins as soon as the blades start opening. The blades take a finite, known (and always the same) time to open fully. This adds a (tiny) extra exposure, which is the same at every shutterspeed.
Hence, the length of the exposure is not measured from the time the blades are fully open, but the extra exposure is taken into account by the people who make these things, and the speed is measured from a point the blades are about halfway open.

What is true is that the size of the aperture makes a difference, as described.
Though the error is nowhere near as large as the 1 full stop that was suggested.

 

[Anscojohn]

What is true is that the size of the aperture makes a difference, as described.
Though the error is nowhere near as large as the 1 full stop that was suggested.[/QUOTE]
******
I wonder if anyone has every tested to find the actual amount?

 

[Philippe-Georges]

There is also a little more than just CLA a Cynchro-Compur shutter.
When I send in my H-lenses, I ask the technician to calibrate the exposing time of the 1/500 point not for the fastest speed possible, but for about 1/350. A compur # 0 can be set for as fast as a little more than 1/400, that is close to 1/500. But by setting it on 1/350, one knows that this is going to stay like this for a (very) long time of use and is not going to 'deviate', if you understand what I mean to say.
As I know that this is about + 1/2 stop, I take this in account when setting the exposure.
BTW, the Copal # 1 and the Compur # 1 shutters are factory set on 1/400 and not 1/500. But, in the H-lenses the # 0 size is build in, and this one can, when in ideal — and near new condition, 'reach' the so called 1/500 speed but "...this is hard to do for that little thing...".

All the best for 2009,

Philippe

 

[archphoto]

Some remarks on the CLA part:
Today's synthetic oils are a lot better than the old oils, they age much slower.
I do all the CLA on my leaf shutters for my 4x5 inch shutters my self, Compur and Copal and have reached times between CLA's
of several years with an occasional shuttertest inbetween just to be shure.

Nobody will complain about an oil change and lube job for their car at least once a year, so why do we complain about some CLA
for our treasured lenses aech couple of years then ?

All the best for 2009,
Peter

 

[chriscrawfordphoto]

Some remarks on the CLA part:
Today's synthetic oils are a lot better than the old oils, they age much slower.
I do all the CLA on my leaf shutters for my 4x5 inch shutters my self, Compur and Copal and have reached times between CLA's
of several years with an occasional shuttertest inbetween just to be shure.

Nobody will complain about an oil change and lube job for their car at least once a year, so why do we complain about some CLA
for our treasured lenses aech couple of years then ?

All the best for 2009,
Peter

Changing oil in the car costs about $20 to do it yourself and $30 if you pay a mechanic. CLA on a shutter costs $150 and is not a do it yourself job for most people. That's why people complain.

 

[chriscrawfordphoto]

Well, it is a C lens, a T*, came in its original packaging with virtually NO sign of use since purchased. The only giveaway is the paint scraped away at the filter mount. I have no idea what the lens cost, as it was a gift from someone who really cares about me.

Could the culprit be too little use? From what I understand, the original (only) owner hadn't used it for the last 15 years or so, and sparingly prior to that.

Thanks so far for your wonderful advice!

- Thomas

The non-use it what probably killed it. These things need regular use or the lubricants harden and cause the problems you're having.

 

[archphoto]

Sorry, Chris, when my car goes for a service job in Holland I pay about € 200,-- each time, I was not aware of the american situation.
And YES, I am fortunate that I have the tools and the knowledge to service my own gear.

Yours,
Peter

 

[edtbjon]

Well, it is a C lens, a T*, came in its original packaging with virtually NO sign of use since purchased. The only giveaway is the paint scraped away at the filter mount. I have no idea what the lens cost, as it was a gift from someone who really cares about me.

Could the culprit be too little use? From what I understand, the original (only) owner hadn't used it for the last 15 years or so, and sparingly prior to that.

Thanks so far for your wonderful advice!

- Thomas

So, it sounds like the lens is a keeper. Anyhow, you are most probably right about "too little use". That is for facts "a known fact" that especially the Syncro-Compurs likes regular exercise (every month or so). The 15 years of storing could have turned out much worse, so you're in luck. (I had an 80mm which "died" on me after being tucked away for some 8 months or so, but after a CLA it was singing again.) Also, as the shutter is "just a bit slow", it sounds like nothing is broken, just some stiffened lubricants. A CLA from some good technican will make you and the lens very happy again. As this was a special gift, I recon the cost of the CLA can be seen as a token for love. It's just a matter of finding a good tech who's affectionate with your gear without robbing you at the same time. And even though we are talking about a Swedish camera in Minnesota, "behöver han inte tala svenska". (A slight paraphrase of what is printed on every Disney film poster in Sweden: "Everyone talks Swedish", as the kids havn't learnt how to read the subtitles yet.)
There are many -blad togs who have all of their gear CLA'd every third year or so. Most of my gear is old and worn, so the cost of a "total CLA" would soon be more than the value of my complete -blad camera bag.
The CF lenses in Prontor shutters are indeed better when it comes to accuracy and reliability, but this comes with a price tag. The glass is "the same" in both the C T* lens and the CF, so there is no reason to upgrade for performance as there is nothing at all to gain.

//Björn

 

[Thomas Bertilsson]

All right, thanks to all for your help. I now understand what I needed to understand. You've been very kind and generous with your advice.

Bjorn, jag ar svensk flykting i Minnesota, so svenska gor bra det ockso!

- Thomas

 

[Q.G.]

I wonder if anyone has every tested to find the actual amount?

Not so much tested, but from experience, about 1/2 stop, maximum.

 

[Q.G.]

When I send in my H-lenses, I ask the technician to calibrate the exposing time of the 1/500 point not for the fastest speed possible, but for about 1/350.

Philippe,

If you let them set the fastest speed of your H-lenses to 1/350, you're more than 1 full stop off.

 

[John Koehrer]

Changing oil in the car costs about $20 to do it yourself and $30 if you pay a mechanic. CLA on a shutter costs $150 and is not a do it yourself job for most people. That's why people complain.

& if you change it a correct intervals. Assuming 3k miles & 15k annually it's 5X20=$100X3yr=$300 every 3 yrs. If you use the "premium" oil change w tire rotation & other fluids it's $40 so, 5X$40=$200X3yr=$600 So it's more to do a CLA on your car than it is on the lens.

 

[Thomas Bertilsson]

Yeah, it's just that it's a fairly large amount of money at once. At least to me $150 is a lot of money.
I don't know what type of budget everybody else is on, but mine is definitely tight. Just having a 150 Sonnar is amazing to me. I will make it work again. Dave Odess is about to receive a phone call.

- Thomas

 

[Ed Sukach]

He is actually right ...

I suggest that you re-read this carefully.

It is because the timing starts when the blades reach the fully open position, but when you shoot with a small aperture, the small hole is fully uncovered long before the blades reach the full open position, and as the blades close it takes a short time for the blades to close enough to cover up the small opening you have at a small aperture.

I suggest that you re-read this carefully. If the 'timing' does, in fact, start when the shutter blades are fully open and only when they are "fully" open, the size of the diaphragm will not be affected much, unless the mechanical movement of the shutter leaves are slowed down ... considerably. Enough to lengthen the "fully open" time significantly.

Those shutter blades move FAST! It would be interesting to measure the opening and closing times, without the exposure time between them. There must be a design parameter dealing with this -- but i can't recall ever having seen objectve data. Anyone out there know of any?

 

[Anscojohn]

It would be interesting to measure the opening and closing times, without the exposure time between them. There must be a design parameter dealing with this -- but i can't recall ever having seen objectve data. Anyone out there know of any?

******It would be interesting. All I have to go on is what was told to me by the old guys. It's not a question of timing, as I understand it; it's the fact? by the time the leaf shutter inertia is overcome, at the smallest aperture, the total exposure has been made before the timing comes into effect. And that it is really only a factor at the highest shutter speeds and the smallest apertures.
And, of course, as I said in my very first post about Thomas's problem, sticky shutter and sticky aperture blades are a totally different matter. He may just need to warm that Sonnar up a bit and give it a few days excercise before venturing forth into the frigid climes again.