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The space in between

T

tor

New Member
As Q.G. suggested in the other thread I guess I should start a new one.

Pasting in what I wrote there:

Made some contact sheets today, and two of the films had inaccurate spacing between the frames. This is the first time this has happened since I bought my 500CM in oktober.
Can faulty spacing occur if the film has been loaded wrongly? I was stressed when I did it and may not have been to careful with lining up the "start". Last but not least, it was about -10 Celsius.

Two out of ten films had faulty spacing. Two images overlapped slightly on each. I think it's due to uncareful loading on my part. Or, thats what I hope.

Cheers/
Tor
 
D:

Can faulty spacing occur if the film has been loaded wrongly? I was stressed when I did it and may not have been to careful with lining up the "start". Last but not least, it was about -10 Celsius.>


I think that I would carefully reload a fresh roll under good conditions and see what happens: as you are in doubt now.

Good Luck:

Gilbert
 
Hi Gilbert,

Spacing is indeed dependent on 'where you start'. It also seems to depend on the total thickness of the film+backing paper.

In the past there was a film vendor (was it Ilford?) who had a batch of film spools with a slightly different diameter core. This has caused some grey hairs I think. These days that issue should be behind us as far as I know.

Wilko
 
Hi Gilbert:

For what it is worth, my 503CW sometimes has exhibited irregular spacing (new and old style backs) (before and after CLA), but always room enough between frames. I did not think about spool differences as Wilko has stated, but I had thought that the actual thickness of the paper backing could be at issue. I also believe that the film I have kept longest in the 'cooler' may exhibit this tendency more than fresh, but I have not bothered to really test this because I have never been close to an actual overlap. Personally, I don't worry about it. It certainlyy does not seem to affect sharpness etc.

I have Rollei TLR also, and they will do the same at times.

Cheers,

Colin

PS. Of course, I always make sure that my 'tilt sensor' is reading the same degrees of left tilt as the matching ambient temperature. -10C would mean tilt the back anticlockwise 10 degrees when loading. Jurgen told me this. ;-)
 
Colin,

That is very kind of you to draw our attention to the reading of the tilt sensor.
I must admit I sometimes forget to look at the display and have been confronted with poor negatives later.

Thank you!
 
Hi All,

I understand that it is possible to set the film advance, where the advance is consistantly too much or too little, what worries me is that you have inconsistant spacing, notably after a CLA. I would bet that the "slip wheel" for want of a better name needs cleaning/oiling.

I have an old style 12 Back, an A 12, and an OS 16, all of which give very regular spacing, to such an extent that on the 12 & 16 backs, by re-setting the counter after the last frame I get an extra shot from every film. OK so this is pushing penny pinching a bit far, but then, I don't suppose it does any harm.

Paul & Colin,

I've looked closely and can't find the "Tilt Sensor" on these older models, so perhaps my negatives would improve if I coupled a Theodolite to the dark screen?

Have a great weekend!
Gerard
 
> Paper backing does make a difference. For ex&le, try putting a > 120 roll in a 220 back. You can do it in an emergency, but the > spacing gets progressively worse between negs as you shoot.
 
The amount film that is transported between succesive frames is not determined or regulated by a gear 'counting' sprocket holes, but by assumptions about the diameter of the take up spool that are built into the mechanism.
With each turn of the take up spool, a length of film equal to the circumference of the spool is transported. Since the diameter of the spool (and with it its circumference) progressively increases with the amount of film + backing paper that is wound on it, the number of rotations of the take up spool must progressively decrease to keep transporting the same length of film.
This decrease is regulated by bits of the transport mechanism inside the magazine's shell.

To ensure the assumptions built into the mechanism will lead to proper results, the spool thickness (diameter of empty spool plus thickness of film + backing paper wound on the spool) must be correct.
Wind more, or less, leader on the spool before putting the insert in the shell and engaging the shell's transport mechanism, and it will be off, leading to 'incorrect' spacing.
That's why the thinner Ilford spools were a bad thing. And that too is why you must stop loading at the correct mark.

The thickness of 220 film, which has no paper backing, of course does not agree with the assumptions about the thickness of 120 film that are built into the 12-back's mechanism. That's why spacing will be off when using a 220 film in a 120 back (and vice versa: a 120 film in a 220 back).
 
Gerard,
the Tilt Sensor is optional on the older cameras and is mounted to the accessory rail. In old catalogues it is called "Spirit level". It's readings have no influence on the operation of the camera and are independent of temperature over a very wide range.

Ulrik
 
When using a Data Recording Magazine, the "Tilt Sensor" automagically programs the imprint unit to rotate the letters, so you never have to turn your head when reading the imprint, regardless of the orientation ('portrait' or 'landscape') of the image...

Of course later, when digital photography came along, the orientation sensed by the tilt sensor was put into the EXIF data, so viewing software can automatically show the image the right side up.
 
O.K.

Guys i have understood and Tilt Sensor is back on stage now .
z04_auslachen.gif

The reaction from HASSELBLAD Germany now is , that they will fight for a full replacement
of the CFV BACK but HASSELBLAD COPENHAGEN still has to agree . Thats all , i know up to now . Hopefully , what they tell me , will be true .
It's nice to have friends in the forum . Have a nice weekend to all of you .
Updates about the progress will follow as soon as there are any news .
Best regards Tilt Sensor .
 
Colin

Strine pal . I love it . Simon is not doing very well at the moment . So , some encouraging words would do him good . Lets hope that he will be able to get his 503CW out of the bag again and shoot some wonderful images of the "Blue Mountains" .

Regards from Tilt Sensor
z04_auslachen.gif
 
Thanks for all the answers. I have not had the time to make any photographs last week. (I'm printing) So I have yet to see if this is human or machine error.

I do have a vague memory of being in the cold and pulling out the camera so that the film advance lever got flipped out. (older A12 does not have the slide holder to fold into,) To get it back into the right position I first wound it in the wrong direction. Should not be possible, but could feel that I was "pulling" the mechanism a tiny bit. Can the lock wear out?

The film I used was Fuji 160S (Formerly known as NPS) I have shot loads of this film and know the film is not the issue. 2 out of 5 films had one faulty spacing (overlapping) respectively.

I shot B/W with a second back borrowed from the school. It has a second mark which indicates where Ilford films should "start". And it was loaded with FP4 (since Plus-X is less easy to find). No problems with that one.

By the way, I have yet to see a back which has "perfect" even spacing. None of the one year old backs in the school that. And was the first to use those 503cw's when we first got them. Same thing then. Same with the Mamiya RB's 7II and c330's I have used. But who cares as long as you have plenty of space for you scissors.

Tor
 
Tor,

Did you mean that the crank on the magazine flipped out?

A ratchet mechanism allows you to wind that counterclockwise ("wrong direction"?) as much as you like, without it doing anything but put the crank in another position. Should be possible. No problem.

After exposing the first frame it should also be possible to turn it the other way ("wrong direction"?). That allows you to wind the roll off, should you want to use the magazine with a different roll of film.
Even when the first frame has not been exposed, it is possible to wind the crank clockwise by tiny bits, and after doing that a few times the 'lock' is lifted, and you can wind it freely from there on.

I too have yet to see a back with "perfect" (i.e. perfectly equal) spacing. But indeed: as long as the frames are separated by enough blank space to cut, there is no problem.
 
Q.G.,

Yes, the crank on the magazine flipped out and I accidently winded it ever so slightly clockwise. (after the first exposure) I know about the counterclockwise mechanism since I use it all the time. The camera is tightly squeezed down between the padding in my minitrekker, and the crank is often being "pulled out by the padding" when I rip the camera out of the bag.

Perhaps the crank had been turned accidently by tiny bits in the bag, disabling the lock. But it happened on two films which leads me to believe that it rather has to do with my loading.
On the other hand I have a hard time to imagine that I would be that sloppy. Loading the film has become second nature. (it is a royal pain to get the paper underneath that film guide with frozen hands though!)

When I try to turn the crank clockwise right now it is firmly locked.

Other than that crank occasionally being flipped to "open", I have to say that the Hasselblad has fantastic ergonomics. Nothing that sticks out.

I just had to make some photographs when I was in the mountains, but the group was waiting as we where climbing down. The weather was rough but beautiful with icy blue/black sharp rocks. I was moving fast with the 'blad wedged in my left arm like a rugby ball. (In that terrain a strap would have smashed the camera)
You hold the camera upside down with the viewfinder fitting nicely in your palm, fingers over filmback and lens facing down.

I fell quite dramatically on some icy snow and landed on the elbow/arm which wrapped the camera. But that grip is a solid one, and you can feel confident that no sharp metal is coming through your gloves or jacket. The camera was shaken around but remained in my firm and comfortable grip.

Later, I fell a second time on some ice but with the camera in the backpack. Sure, those Lowepros have good padding but I felt less confident than when holding it in the "rugby grip"
Tor
 
Jürgen:

HASSELBLAD Germany now is , that they will fight for a full replacement of the CFV BACK but HASSELBLAD COPENHAGEN still has to agree .>

I am sorry to hear about your situation. By now they should overnight a new one to you.

I have been thinking about Simon lately and hope he recovers soon.

Regards:

Gilbert
 
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