hasselblad macro exposure?

[MisterTransistor]

I am a reasonably experienced film photographer from way back, and I have recently started using my father's Hasselblad, which regrettably he is unable to use now. Compared to film SLRs one major difference is the use of a separate light meter but I don't find that much of a problem.
I want to try some macro shots and have ordered an extension tube. But I'm wondering how to get the right exposure? I was initially thinking of daylight shots, but I also have a flashgun with a cable that should connect to the Hasselblad lenses, although I have not tried it yet, so I don't even know how to use it for normal shots.
Any basic pointers appreciated!
Andrew

[Malcolm_Stewart]

I don't know the precise answer, but this pdf for Kenko tubes might have some clues. It gives specific examples and the basic formula, so you should be able to get somewhere close.

[Rhys]

which extension tubes have you got? IIRC it was 2 stops correction for the big one. I used a meter prism finder - much easier lol

[MisterTransistor]

I got the big one - 56E. I'm using a 501C/M and I don't have TTL metering of any kind. I don't understand how that can work with flash anyway...
Basically I'm trying to understand how people get those superb macro shots on Flickr and elsewhere. There are three problems to solve -
1. get the subject to fill (a good part of) the frame
2. get enough depth of field
3. get enough illumination
When I use the 56E with the 80mm planar, the subject is about 5 inches from the front of the lens, and looks about life size in the viewfinder. My hope is that because the distance from the lens is so large (in macro terms) the depth of field at small aperture will be say half an inch. When I scan the negatives (I have an Epson V700) I will then be able to crop quite tightly and still get a decent pixel count.
This leaves illumination as the unsolved problem. As an old fashioned film user, I would look on my flashgun and choose an aperture appropriate for the subject distance. Shutter speed is largely immaterial. I don't think that works for macro distances though ...
Anyway, I ran off a roll this weekend and have sent it for processing. Some natural light shots with long exposures and the rest flash with guesswork. I'm rather expecting the latter to be either underexposed or else very overexposed - I suspect it's hard to get the balance right.
Anyone else tried this kind of thing?
Andrew

[Rhys]

I had a 503CW which had TTL with an appropriate adapter (though never used it - had all the kit on my old CX but that got nicked before I had a chance to use it)
As for the depth of field, you can close the lens down to check that. I'd say 2 stops for the 56E would be about right - I would have checked with a meter prism for you but I've sold all my blad stuff now due to lack of use.

Be interesting to see how your shot came out.

[daft_biker]

When I use the 56E with the 80mm planar, the subject is about 5 inches from the front of the lens, and looks about life size in the viewfinder. My hope is that because the distance from the lens is so large (in macro terms) the depth of field at small aperture will be say half an inch.

Half an inch is probably a bit much DoF to expect when shooting at lifesize - f/32 on a small format gives me about 2mm. Maybe with the 80mm on MF and not going 'pixel peeping' you might get a bit more. (try dofmaster.com

The distance from the lens shouldn't matter directly - if anything using a wider lens which means being closer to get the same magnification you would get more DoF.

Also note with the DoF calculations how much focus is in front and how much is behind the point where you focus. The wider the lens, the more you stop down and the larger the circle of confusion you use the greater the % of the available DoF will be behind the point of focus.

[MisterTransistor]

Found this manual

It shows that with the 56E on the 80mm stopped down to f11 the DoF should be about 4 to 5 mm

Andrew

[MisterTransistor]

Well, I've got the negatives back from Peak Processing and the exposure is not too bad, some of the flash shots are underexposed but others are OK. However, having scanned them at 3200 dpi, I'm very disappointed with the lack of sharpness. I can see the DoF effect but nothing is really pin sharp, I certainly can't crop the image the way I hoped. These are Fujicolor Pro 160S but I have had similar experience with B&W negatives. Frankly I'm beginning to wonder about the CB planar. I expected the Hasselblad package to be superb but I'm not finding that. I have been scanning my Dad's old 6x6 negatives from the 1960's and some of those *are* very sharp - taken on a Contina Reflex with a Steinheil Cassar lens.
Hasselblad/Zeiss Planar with tripod and flash, stopped down, damn well ought to be sharp.
Andrew