Help for angle of view conversion

alcelc wrote:

However, I am afraid that the focal length of 7.5 f/2 be too short to use any usual 10mm or 16mm or longer extension tube.

Yes, it seems tests have proven this is correct !

I tried to put on a 16mm tube on 7-14 f/4, it can't focus at all throughout 7 to 14... I suppose a shorter 10mm tube might be OK around 14 (but mine was broken because of my curiosity on how it works, can't communicate with the camera again after disassembling and reassembling of it another day, looking for a replacement ).

Sorry to hear about your broken lens Curiosity is more important tho !

If you really wish to engage in macro shooting, why not consider a proper native M43 macro lens like Olympus 60 f/2.8 (the most recommended by members), Panasonic 30 f/2.8, Olympus 30 f/3.5 or the older Panasonic Leica 45 f/2.8 that all produce excellent IQ, fast and accurate AF, as well as the usual size advantage over using adapted MF lenses...

Well I am already engaged in macro shooting, I'm making this project mostly using a Canon 100mm with Smart Adapter on the GH4. I'm really looking for a wide angle lens, but the unique macro possibilities of the Laowa 15mm macro are really teasing me.

Judging from the min shooting distance of 12cm of Laowa 7.5, I suppose even if you can put on an extension tube the shooting distance could be virtually 0cm, basically not workable for a lot of macro/close shooting situation.

Right!

The Laowa 15 macro is better, but still costy (US$500 as per B&H?), relatively huge comparing to native M43 native lenses (410g and 83.8mm long having a filter thread of 77mm), not to mention the need of an adapter to convert it into a M43 mount for more weight and size (if you have keen interest on this lens, better check the compatibility since if using a EF mount option, the flange distance of this lens would be 44mm and so a 24.75mm adapter must be used to allow a proper focusing of this lens on the 19.25mm flange distance of M43 system. Not sure how the min shooting distance of 12cm of this lens would be affected. Might possibly affect the macro ability?

Wow, I did not think of that. They do sell the 15mm with an optional adapter for M4/3, so I was supposing they thought of that. Do you mean that the adapter should be one with optical parts as well ?

Just my 2 cents

Worth way more than 2 cents. Thanks a lot !