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Hasselblad HC Extension Tubes question.

aDam007

New member
Hi guys,

Quick question about the HC extension tubes, I've seen the chart, but it's a bit difficult to determine practical uses from a chart of confusing numbers.

So what I'm asking is, what are the general uses for a 13 vs 26, vs 56 extension tube when you're using a 50, 100, 150 since those are the three lenses I'm pretty set on owning (btw if anyone is selling PM me). I do a wide range of things from amateur macro work, to paid portrait work, some food and product work, fashion etc.

I have the a set for my canon setup, so is it similar in usage?

Thanks,
Adam
 
Last edited:

Udo

Member
Hi Adam,

first of all the numbers attached to the extension tubes (13, 26 and 52) give you the thickness of those extension tubes in mm. The longer the tube is (longest is 52 mm) the closer you can get to the object. And this is exactly what you find in those tables you mentioned for each HC(D) lens plus the depicted areas. These tables are available for metric and imperial distances. Furthermore those tubes can be stacked. All lens' electronic functions continue to work due to electrical contacts in the tubes.

Regards,
Udo
 

aDam007

New member
Yeah, as I figured it's just the same as extension tubes I use for canon.. I mean, same principle.

Ok, so let me rephrase my question since I don't actually have 13, 26, 52 tubes for my canon, the numbers aren't the same. I was wondering if say I used the 100mm, then the 13 would let me fill a subjects face with the lens, and a 26 would let me get both eyes within the frame, and a 52 would allow one eye? Is that kinda the spacing?

Guess unless someone has extensive use with them, it's hard to answer.
 
P

Porpoise

Guest
I never used the HC rings but it's not that hard:
1/f = 1/d + 1/D
f: focus length of lens
D: distance sensor to lens
d: distance subject to lens
For a 100mm lens with a minimum focus distance of 1.2m, the distance between lens and sensor is 109.1mm. If you add 26mm with an extension ring, the minimum focus distance will be 38.5cm.
Magnification is D/d. So here you should cover about 2.85x your sensor size.
Mind you, distances on the lens scale normally indicate d+D.
 

P. Chong

Well-known member
I use the tubes extensively. I have the 52 and 26, and use both of them stacked or individually. With the 120 Macro, and using both the 52 and 26 for a total extension of 78, you can get the whole of one eye covering the entire sensor area for my H3D-39.
 

aDam007

New member
Interesting Porpoise, thanks for the lesson. It's just a bit hard to think of coverage in those terms. But at least it'll give me an idea of what I can expect.

P.Chong, I'm obviously gonna have to come over and test your gear ;)
 
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