Tamron 28-75 + macro rings?

[mesmerized]

Hello there,

Has anyone here tried to use macro rings with the Tamron 28-75 f/2.8 on a Sony A7(iii) body? I'm really tempted to get the Sony 90mm G f/2.8 macro lens but I figured that getting a set of macro rings and maybe saving some cash would be the wiser choice. I know macro rings will never give me what a real macro lens will, but how much magnification can I get out of such a combination?

Cheers

 

[Richard Crowe]

I have both a set of macro rings (extension tubes) as well as a set of four close-up lenses in 67mm. I got the close-up lens set as part of a lot of filters which were included when I purchased a used lens. However I have never used them. I think that I will make a dedicated effort to use both the extension tubes and the close up filters this afternoon. It will give me something constructive to do during my COVID-19 social distancing...
The reason that I have not used the extension tubes is that the bare 28-75mm lens has provided the close up capability that I have needed. The lens provides between a 1:3 at 28mm and 1:4 at 75mm magnification...

 

[Richard Crowe]

My extension tubes/macro rings are 10mm and 16mm plus I could combine them to add up to 26mm...

Here are the magnifications for the Tamron at 28mm
10mm .65x magnification
16mm .82x magnification
26mm 1.18 magnification
For the lens at 75mm
10mm .47x magnification
16mm .55x magnification
26mm .69x magnification

I also have a set of close-up filters/diopter lenses
For the lens at 28mm
+1 diopter .29x magnification
+2 diopter . 32x magnification
+4 diopter .39x magnification
+10 diopter .60x magnification
For the lens at 75mm
+1 diopter .44x magnification
+2 diopter . 54x magnification
+4 diopter .74x magnification
+10 diopter 1.35x magnification

Reference for above: https://www.cambridgeincolour.com/tutorials/macro-extension-tubes-closeup.htm

I don't use either the extension tubes or the diopter lenses because I have a 60mm macro lens which will provide a 2:1 image ratio without any added tubes or diopter lenses. However - my calculations from the above table indicate that with this lens I could achieve a maximum 2.43x to 1 image ratio with 26mm of extension tubes and if I had a 62mm diopter filter, I could achieve a 3.8x to 1 image ratio.