Teach me about "diopters"

[FowlersFreeTime]

Instagram served up this interesting offer from PolarPro in my feed last night:

SHIFT Diopter | Shortstache Edition

Enhance your close-focus cinematography with the Shift Diopter – Shortstache Edition. Designed for creators seeking crisp detail, premium glass, and cinematic depth.

www.polarpro.com

Seems a bit pricey, but you do get a set of 3 filters, and claims to give any lens "macro-like" short focusing distance. I have no idea what magnification I could achieve on my standard Sony 16-55 f2.8G lens, but I am curious about that and the Tamron 50-300 because I often carry both and they have the same 67mm filter size. Is this a gimmick or should I have bought this instead of the Tamron 90mm Macro I got for Christmas?

 

[iamdlewis]

I have a diopter. Haven't done much with it yet but I can add some photos this weekend so you can get an idea.

 

[Slug]

Have used them for some time in conjunction with 105 mm Sigma and 90 mm Olympus. There’s quite a variation in quality and I’ve found Marumi achromat excellent. Bear-in mind depth of field is very shallow so focus stacking is helpful. I use a +5 but some users stack several together.

• ILCE-6400
• 105mm F2.8
• 105.0 mm
• ƒ/16
• 1/60 sec
• ISO 250

 

[Slug]

My Sony outfit. I use +3 on the Sigma 105 and +5 on Olympus 90.

• iPhone 8 Plus
• iPhone 8 Plus back dual camera 3.99mm f/1.8
• 4.0 mm
• ƒ/1.8
• 1/40 sec
• ISO 20

• iPhone 8 Plus
• iPhone 8 Plus back dual camera 3.99mm f/1.8
• 4.0 mm
• ƒ/1.8
• 1/15 sec
• ISO 100

• iPhone 8 Plus
• iPhone 8 Plus back dual camera 3.99mm f/1.8
• 4.0 mm
• ƒ/1.8
• 1/24 sec
• ISO 40