Winding crank slipage normal?

[jim_gardner4]

After a long time of wanting one and saving cash I have finaly brought a new

503cw. It arrived this week and I put a film through it just to try it and get

used to it. When I wind the film for the first 3 or 4 frames, the winding

crank has tension on it all the way through its travel. By the 5th or 6th

frame the last 15 degress (roughley) of travel has little or no tension. As I

expose and wind on through the film the "loose" part of the travel gets

greater until it gets to approx 45 degrees. I developed my film and had a look

at the frame spacings which all seem equal. Can any one tell me if this

progressive looseness is normal as you make more exposures? Thanks.

[russ_britt3]

The film needs to advance different as the film is used, because roll size changes. I hope you can figure out what I am trying to say. But bottom line if the spacing is right on the film all is well.

[antonio_garcia_russell]

I have a new 503cw too - can say I have experienced the slippage you refer to. I would take

it back to the store and have them look at it or let you try another to see if it is an isolated

issue.

[antonio_garcia_russell]

update: just fired of 12 shots (without film) and i did notice that from frame 6 onwards

there is a slight sensation of slippage following a tiny clicking sensation in the winder,

which dissapears after frame 12, i.e. for the final wind on.

[jim_gardner4]

Russ, understand what you are saying and that makes sense but I'm sure my Bronica never used to do it.

Antonio, mine does it with film in but cant say I have noticed it without film in.

[q.g._de_bakker]

I'd say Russ is right. The winding mechanism in the back 'kicks free' earlier as the frame numbers go up, but the wind crank has to complete a full 360 degree turn, no matter what.

[hasselblad technician]

Jim,

 

The short answer to your question is, "Yes,it is normal". Now here's the long answer. When you turn the winding crank on the camera body, you are winding the camera body, winding the lens and winding the film magazine. The tension of winding the camera body and the lens are always constant. What I mean by this is that to wind the camera body and the lens, a steady, constant amount of tension is felt through the entire cycle of turning the winding crank. But when you have a loaded film magazine attached to the camera body, this all changes.

 

When you are turning the winding crank on the camera body with a loaded film magazine attached, you feel the added tension (or load) of moving the film in the magazine. When you advance the camera from the first frame to the second frame, you are pulling a certain amount of film onto the take-up spool. With each successive exposure, the take-up spool doesn't have to turn as much to advance the same amount of film for the next exposure, because the diameter of the film on the take-up spool increases with each exposure.

 

So when you wind the the camera after the first exposure, you will feel a certain amount of tension (or drag) on the winding crank for almost the complete cycle of the winding process. But with each successive exposure, the tension (or drag) on the winding crank will lessen sooner, during the winding cycle, as you don't have to pull as much film onto the take-up spool.

[jim_gardner4]

Understand perfectly, thanks. N.B,I just took a scrap film and measured the amount of film that is unwound in one turn of the film spool (just holding it in my hand)at the start (nearly full spool) and end (nearly empty spool). The difference is well over an inch! I realize that one turn of the winding crank doesnt neccessarily mean the film spool turns one turn but after reading the above I wondered how much difference there was from start to finish. Bit anal maybe but I had never thought about it before and didnt realize the difference would be that much. Thanks all for the help.

[antonio_garcia_russell]

So David, just out of interest. How does the camera actually compensate for the less film on

the spool. Does it use gears or does it use some sort of de-coupling system inside the film

magazine so that the winding action does not carry through to the film back?

[hasselblad technician]

The amount of film that is actually moved from one exposure to the next is determined by the film magazine. This is accomplished by a number of arms and gears. Once the proper amount of film for each exposure has been transported, the drive system in the film back is disengaged, allowing for the complete cycling of the film magazine without transporting any more film.