Reverse-Macro Imaging

[BW]

I se nothing funky with hazel catkin on my monitor. I wouldn't call the highlights "blown". It certainly is well within level of acceptance. But standards may vary.

[John Koerner]

Interesting ... almost looks like an x-ray more than a photograph.

How did you achieve that affect?

[BW]

Its a double exposure.

[Bjørn Rørslett]

An example of stacking lenses. In this case, without reversing any of them. 105/4 Micro-Nikkor and 105/4 Bellows-Nikkor in combination.

Fly in early spring. 3X (taken from a small jpg, the original file not accessible at present. The original has been printed large)

[Bruno Schroder]

You had mentioned that trick of yours before, Bjørn, but I think it is the first time I see what you can do with it. This is more than excellent.

[BW]

How do you calculate the magnification, other than the object size in relation to image size?

[Bjørn Rørslett]

How do you calculate the magnification, other than the object size in relation to image size?

Shoot a ruler - read out the covered length of it - divide by appropriate sensor dimension == M (magnification)

For stacked lenses, one frequently sees the formula M= (long focal length)/(short focal length), assuming the longer lens is the master lens mounted to the camera. Sometimes this relationship predicts the true achievable magnification, sometimes it is off and then by a good margin.

It is tempting to use the master lens with automated aperture setting, however, the better result normally is acquired by stopping down the front lens and keeping the rear lens wide open. If this method is adhered to, putting in an E2 or something similar to be able to flip the aperture back to wide open for focusing is beneficial.

[BW]

I thought there was a magic workaround that didnt involve that boring exercise

[Bjørn Rørslett]

I just edited the previous post to indicate a certain magic might exist, but it is not infallible.

For example: 50 mm lens stacked on 200 mm => M ~ 4 (200/50). Or 4X life size if you prefer that notation.

Whether or not the front lens should be reversed is found by trial and error. It has to do with the matching (or mismatch) of pupils for each lens. By keeping the master lens wide open, vignetting caused by the rear component is mitigated to a large extent.

[BW]

Thanks Bjørn!

[Bjørn Rørslett]

This is ice crystalline structures at 2X. Actually one would imagine 1:1 because 2*105/4 lenses were combined, but no.

(so much fine detail here I had to compress the jpg quite a bit to make it fit the max.attachment size)

[John Koerner]

How do you calculate the magnification, other than the object size in relation to image size?

You might want to bookmark this series of magnification calculators.

It has everything from bellows, to reverse ring, to lens-stacking calculators.

[Bjørn Rørslett]

Shooting a ruler is still the simpler approach. Might be more appropriate as well if the optics cannot be modelled as a 'thin' lens with zero internodal space.

[Jakov Minić]

Bjørn, the ice crystalline structures are bitingly detailed. They just scream with the texture and colors. Lovely!

[Bjørn Rørslett]

Even this small jpg at normal quality level would be about 6 MB in size ... Had to compress to mediocre quality to make it fit here. So yes, these structures are very rich in detail.