Yes, the Laowa doesn't have a slot for the lever to go into. I did wonder about removing the lever but decided against since it's only for an experiment and Murphy's Law says that when I want to put it back I won't be able to find it or, even worse, damage the tubes while removing it.

TBH, I was really surprised that there was nothing in my box of odds and ends that would do the job. I thought that what is in there would be able to connect anything to anything else. Unfortunately not.

Steve

Thanks, an interesting suggestion. I've just tried it with the 1.4TC and it works! Goodness knows what a TC that's optimised for long lenses will do with a short focal length lens that's optimised for short distance, high magnification. There's only one way to find out, though. A whole new area for tinkering and experimenting has opened up ... .

However, interesting as it is, it isn't quite what I was looking for because of the extra glass in the TC. So has anyone any other suggestions that do not involve extra glass? And please don't suggest removing the lens elements from the beautiful, precious, oh so useful 1.4TC .

Steve

Today, Mrs L. very kindly gave me a nut that she had found on a tree while out walking. This wasn't entirely random, there was a reason for it. Anyway, the chance to photograph a fresh nut was too good to miss. So I set it up in the macro rig and proceeded to adjust lighting, alignment, focus and all the other things that you need to do before taking a photo (or in this case, a whole stack of photos). Then while doing a final check through the viewfinder - the nut dropped out of its leafy involucre! Thankfully, the nut itself didn't roll somewhere inaccessible so it was put back where it came from. To avoid falling out it obviously had to be upside down. But so what, that's why post-processing software has a 'rotate' button .

And here are the results of the nutty hour or so. K3 + Sigma 70mm macro, stacks of about 40 images processed in Affinity Photo. Affinity Photo must be congratulated on how well it handled alignment with the second image stack - the nut slowly but surely increased its angle of lean while the photos for the stack were being take (definitely not good practice for macro photography...).

Thoughts, comments etc. welcome as usual.

1. After the fall



2. Back again (and upside down)



Steve

First, the reason for the question... Just for fun, I thought I'd put some extension tubes on the Laowa 25mm x2.5-5 macro lens. They didn't fit. The reason is that this manual-everything lens has a plain bayonet mount - no electrical contacts, no screw drive, no coupling of any sort to the camera and, crucially, no slot for the stop-down coupler lever that is present in the extension tubes. The lack of a slot doesn't matter when mounting directly on the K3 (or, as far as I understand it, other DSLRs) as there is no lever.

And now the question... Is there a way of linking the lens to the camera via extension tubes? It must be (a) practical (no surgery on lens or tubes, please!); (b) cheap (this is just for fun, the resulting images might just be a mess of diffraction and aberrations ) and (c) easy (e.g. no searching the world for an obscure adapter only made in March 1974).

Hopefully, one of you good people who enjoys playing with old or unusual lenses might have an answer.

And finally... For info only (it won't help here), the Laowa can be mounted on a Q - the Q to K-mount adapter does not have a stop-down coupler lever (or indeed, much else at the lens end). But I don't know yet whether the results are worthwhile. And I don't have Q extension tubes .

Steve

Thanks. It confirms that the Laowa needs to be at or near max aperture to minimise diffraction. So it's always going to be a trade-off between DOF and diffraction. And that takes it from science to art....

Steve

It isn't the arc itself that niggles (yeah, can't do anything about that), but within each arc of dots and dashes there are a couple of dots that don't line up with the others. Camera movement between shots? A quirk of the alignment algorithm in the stacking software? Or perhaps the earth had a wobble in its rotation??

Steve

The ideas are good, the subject matter is spot on, the pictures are eye-catching.

And definitely worthwhile experimenting at the wind farm. The effect you've achieved with the turbine blades is striking IMHO. And the Morse code star trails have grown on me. At first viewing, I thought it would be better if the stars were single points of light. Now, after coming back to the pictures several times, the broken trails seem to complement the turbine blades - something to do with motion. PIty that the dots and dashes aren't in line - slight camera movement between shots? And aircraft movements at night within a photographer's field of view should be banned. You'll have to go back and do it again . Incidentally, I prefer the stacked version, the HDR version is way too bright for my tastes.

Steve

Would diffraction be a problem if there was a diaphragm and the aperture was reduced? The reason I ask is because the Laowa 25mm x2.5-5 does have a diaphragm (manual, no communication with camera), physical aperture fully open is f2.8 and can close down to f16. However, I'm not closing it down much because of concern that gains in DOF would be offset by increased diffraction. The concerns come from some tests on websites carried out by people with a lot more knowledge and experience than me. One day, perhaps I'll find the time to do some tests of my own, but life does seem to get in the way...

Steve

That last one is a superb skyscape . The top right corner seems a bit dark - was the sky really like that, is it a wide angle lens lens effect, was a polarising filter used (etc.)?

It look like an interesting lens for APS-C, too, as well as full frame - a compact, light weight, short standard zoom equivalent to the 35-70mm that came with my first SLR (nostalgia sets in...:wink.

Steve

And thanks from me, too. Absolutely fascinating, I had no idea that this was the cause of ferns springing up randomly in the garden!

Technically impressive. Clearly a very, very small depth of field and, if I've got the numbers correct, 3mm FOV implies approx x8 magnification. Aesthetically, however, I'd like to have a bit less OOF distraction in the foreground. But that would have meant more images in the stack, of course...

Steve