Very nice! Have never tried that but looks very interesting. 👍
Very nice! Have never tried that but looks very interesting. 👍
Because of the interesting diagonal bokeh shot, I got to post some of my bokeh experiments with external factors as well:

Trying to bokeh hole in my idea? by simple.joy, on Flickr

Overwhelming pressure by simple.joy, on Flickr

Choc-full of sweetness by simple.joy, on Flickr

Time to get in shape for Christmas! by simple.joy, on Flickr

Optical essence on fire by simple.joy, on Flickr
All made with different lenses... Usually most types of experiments like that seem to work better with big diameter lenses though.
Another technique I like to experiment with from time to time is playing with bokeh in the foreground. It might be worth it to mention, that not every lens works equally well when it comes to bokeh in the foreground. It can be a recipe for disaster with some lenses which are very flare-prone and some lenses don't seem to be able to create a lot of pleasing bokeh there or at least not much in terms of bokeh balls...

The thought that bokeh is important... just brush it aside! by simple.joy, on Flickr

Shooting wide angle by simple.joy, on Flickr

Sorry for the meme... but this cake IS a lie! by simple.joy, on Flickr
(faked steam)

Hello there! I'm kind of self-reflective. by simple.joy, on Flickr

... but it was your own poison! I'm just a tool. by simple.joy, auf Flickr

No questions asked by simple.joy, auf Flickr
Of course this is often the result of some trial and error, but it usually pays to experiment with different lenses, materials and lights.
Here's a new capture of the star-variety:

Manipulating light with imperfect tools... by simple.joy, on Flickr
Triangular bokeh of a Ricoh FF1 lens 35mm 2.8 as mounted on A7RII
Thanks - looks great! I particularly like the shot of the red tree (I assume). Also quite the elaborate adaption you have once more - excellent work. I have no idea how close you're able to focus but if you have some closer shots highlighting the triangles even more, I'd love to see some of those here as well.
I've already displayed a number of shots made with a couple of my triangular bokeh lenses, but here as some more:

Triangulating the essence of music by simple.joy, on Flickr

Enormous weight by simple.joy, on Flickr

Jester single moment by simple.joy, on Flickr

Ten up, ten down! by simple.joy, on Flickr
Front cell focusing so even if I could increase that the SA would become more dominant than anything else. The MFD is 90cm / 3' now and between 4.0-5.6 the aperture is more a ninja triangle so at least a Sony FE extension tube is needed to get that working with a tighter/triangle aperture. For macro adaptations I stick to M42 solutions though; mounts, tubes and bellows. And lenses with more blades or without blades.
The aim here was to make a really small pancake lens with an acceptable image quality. You saw the old conversion, meanwhile it is a more 3D printed, more slick design with an extra ring added to handle the aperture better.
Fascinating! Thanks for the explanation. M42 is one of my preferred mounts to use as well, because there‘s a lot of stuff available for it and I also got custom recessed M42 lens boards for my bellows. In order to be able to use bigger lenses or reverse smaller ones inside of my bellows, I also use M58 a lot.
I‘m continually impressed by your 3D printing abilities - is it hard to measure all of the necessary parameters? I wouldn‘t even know where to start. 😅

Your choice! by simple.joy, on Flickr
With this thread in mind I had to make an adapter FE female to M42 male so I could use some FE mount converted lenses on the M42 helicoids or M42 bellows. Not usable for the native FE mount lenses without the aperture control added. The Ricoh FF1 35mm 2.8 pancake and one of the converted Fujinon 45mm lenses were used for the images.
That's really great - thanks a lot for sharing those, I like the shape a lot! What was DSC09831 shot with? Seems to provide very nice possibilities for creating significantly sized triangles, which is always great.
I had a conversation with someone on flickr about star-shaped bokeh lenses and while checking some of my lenses realized that the Asahi Super-Multi-Coated Bellows-Takumar 100 mm f/4 has a very interesting aperture. It's round wide open, then some ninja stars, then geometric stars, then an octagon and fully stopped down it's round again. The Leitz Summicron-DR 50 mm f/2 slightly similar, but doesn't show that variety of shapes. Found that very interesting.

The bokeh is out of the bag... by simple.joy, auf Flickr
Triangular shapes of the Ricoh FF1 Rikenon 35mm 2.8
Pentagonal shapes of the Fujica 35 EE Fujinon 45mm 1.9
Salvaged lenses of compact cameras.
Thanks for clarifying - I always appreciate someone trying unusual lenses like that. As I've said before, I don't feel quite ready to try something like that, but at some point I've got to think of some solutions for the (non insignificant) number of lenses I still need to adapt properly. 😅
BTW. have you created an overview of all your adapted/3D printed solutions and findings on those lenses on some kind of blog etc. or is all of that spread over on the dpreview forum for the most part? I think it would warrent its own kind of place or perhaps an article/series. As far as I'm aware not many are attempting adapting lenses which don't have a regular thread (do you know Matt's crazy lens adventures on flickr? He does use such lenses regularly, I think...) or an already existing adapter, so it would be great if it was documented somewhere.