Insert matches back, why important?

[wkjagt]

Frequently I see advertised that an insert matches the back when it's a

Hasselblad back. Why is that important?

[William Kahn]

I researched the same question a couple of years ago and the answer I got (If I remember right) was that each back/insert combination is hand-crafted to some extent for the best fit and mechanical match. That's why you have matching numbers on both pieces.....

[john_gleason1]

From the archives:

 

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=001mOe

 

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=001QRZ

[ken_schuster]

The reason the inserts are carefully adjusted and serial-numbered to match the backs is to get as close as possible to perfect film plane positioning and repeatability. If the the insert can jiggle as little as a millimeter toward or away from the lens, the film plane will be forward or back-focusing. If it jiggles left and right, critical registration positioning will be off. Zeiss glass is wonderful, but if the film's not where it should be, you could get the same image quality with much less expense. I have often seen photographers treat their lenses like fragile butterfly wings, and then toss their camera backs into a drawer.

[simonpg]

The film backs are a precision instrument and the "matching" of magazines to backs is part of Hasselblad's precision manufacturing.

 

While Ken's response is perfectly accurate, the reality is that one need to be too fussed about having "non-matching" magazines/backs.

 

The reality is that many many professionals who had kits with numerous backs often mixed magazines and backs without realising it - pressures of commercial photography.

 

Personally I've never heard a pro say he had an issue with un-sharp images due to a mis-matched magazine / back.

 

Yes, in buying all my backs second hand, I have preferred to have matching magazines/backs for obvious reasons. I suggest to others they do the same.

 

But, I do have one back that has a magazine with no serial number sticker fitted to it ( I have no idea if it is the original matching back or not). It was like new and the ONLY current version back for sale in my state at the time I needed one.

 

So, maybe the sticker just came off it - who knows. But this back has never produced anything other than razor sharp images where they should be razor sharp.

[jrsmith]

Willem

 

I have four magazines. Three of them have matching insert numbers, one does not. I can see no difference whatsoever in image sharpness between the matching ones and the mismatched magazine.

 

John

[Ed_Ingold]

Hasselblad inserts are hand-adjusted so that the film-flattening rollers on the insert align with the corresponding rollers on the back. All my inserts match, so I can't say what a mismatch would do. As long as the film doesn't bind, any effect would be limited to the extreme top and bottom of the image.

 

Unless you scan with a glass-plate holder and exercise extraordinary care (heavy tripod, good technique) when shooting, you might not see the difference between an Hasselblad and 35mm, other than grain.

[wkjagt]

Hi, thanks for the info. I was just very interested, not because I have an unmatching back, but because I wanted to understand the importance of it. I have just bought my first Hasselblad, that's why I asked.

I don't scan with a glass plate, because I print my photos in the (color) dark room. Maybe for that it would be important if the matching back issue was in fact important, because the good old dark room is supposed to get the maximum quality out of a neg I guess (if using a good enlarger with a good lens and if I knew what I was doing in there etc. ofcourse.)

[stever_max]

Simon Galbally:But, I do have one back that has a magazine with no serial number sticker fitted to it ( I have no idea if it is the original matching back or not). It was like new and the ONLY current version back for sale in my state at the time I needed one.

 

I have seen back without numbers. They are very old backs.

 

Steve

[q.g._de_bakker]

But even very old backs have serial number on both shell and insert.

[kparratt]

Willem,

 

Remembering an A12 I sent for service to Hasselblad in Sweden, one that did not have a matching insert. It came back working as new, and as part of the service, the insert was adjusted to the housing, and had it's new number marked on it. From then onwards, it became a "matching" insert.

 

So it's a procedure of production-line assembly, and of service if required. (But it would need to be done by someone who really knew the job.)

 

Cheers, Kevin.

[simonpg]

QG is right. And in any case my back was manufactured in 2001. The residue of the sticker is in the space made for them.

 

Kevin makes a very good point. When my "unmatching" back/ magazine were serviced a year ago the report came back - adjusted magazine to back fit. But no new sticker was added - Aussie authorized service company rather than Hasselblad in Sweden.