New SIGMA-SA macro tube......

[Guest .]

Uwe's (Netzuser's) Invention!!!

Hi All,

I have to point out here, that the macro tube is Uwe's invention. He built the one, I am presenting above.

I just did the test shots.

Uwe is a real genius with such nice projects! :z04_TUjXSMUS: He was the first who put a SIGMA-SA bellows into practice.

Further, it was his idea to do a DIY retro conversion with SIGMA-lenses.

Later then it was my idea, to do a non-destructive retro adapter for macro use.

Well, as soon as you have the raw-materials i.e. both bajonet-rings (camera and lens) it is not all that difficult to do these accessories.
Normal technical skills and the ability to do some radio/micro-soldering should do!

Serial production is difficult because of a shortage of bajonet raw-material.
If it was possible to produce it in larger quantities, you would not need old cameras and lenses for each piece.

See you with nice pictures

Klaus

 

[Guest .]

Additional 45mm Macro Tube

Hi All,

nobody can stop me!

I built an aditional 45mm macro-tube. Sure, that it can be combined with the above mentioned 20mm-tube from Uwe's production.

The making was a lot of work (took me about 4hs!) but it is no magic to do.
45mm you simply reach using the complete light-case of an old SIGMA SA300.
The only problem then is, to have both bajonettes arranged half way centric, since the light-case is designed asymmetrically.

To have it impermeable to light, I simply used some insulating tape.

The elecric wiring is the same as with our bellows ... just compare HERE.

View attachment 922

Let's have a look!

SIGMA 18-200mm OS

All that goes without macro-aid: ......................... / ...........................Both tubes fitted

View attachment 923 View attachment 924

Findings:

1) The OS works beautifully within macro range! The macro is done freehanded (ellbows supported on the table) at 1/4s!! shutter-speed 173mm focal length and ISO 400. I used a dim 40W desk lamp on purpose, since we are talking about AL-OS-macros!

2) Image quality is considerably well with the lens on open aperture!

3) The depth of field runs towards zero (as you can see!)

4) The loss of light is something around one aperture value (you can live with that!)

5) As I indicated above ... the bigger macro-tubes can only be used with the longer focal lengthes of the lens although magnification can be increased visibly to an estimated 1:1 ratio ... therefore, Uwe's 20mm tube is the best match with the 18-200mm DC OS lens.

Summing it up .....

The more I am concerned with macro-shooting, the more I go for using flash-lights. Using a flash is the only way to have enough light for slowing down aperture to an extent that ensures a broad DOF-range, frequently needed for insects.

I am very much looking forward to make new experiences with the new macro-tubes (combined with OS-power) as soon as I have acceptable light.

Well, I do not like test-shots all that much ... therefore I did all in my power to have a considerable macro at hands for illustrating the above mentioned devices. This was a difficult thing to do, because of very little light available in the garden.

Exposure: ISO400 / .....1/30s.... / F:5.6 / 115mm

At least I managed this one this afternoon .... a very little moss-plant carrying a water-drop.

View attachment 925

See you with nice pictures

Klaus

 

[netzuser]

Hi Klaus,
thanks for this informative posting.
Very interesting to read your findings and reccomandations.
Hopefully some users will participate.
Regards
Uwe