Things are getting spooky round here.
Firstly I viewed Duncans Poppy image bang on the sounding of the 2 minute silence a week ago. Yesterday I viewed Chris's Grandfather clock as the first image in that gallery viewing, see his comment on it. Now today having posted on the use of extension tubes and zooms but with no sample images, I step out to disconnect battery charger from the car and ......... a wasp landed next to my hand. A quick rush inside to get extension tubes and zoom lens on the camera, pick up a flash, reflector and monopod and I managed two sample pics before it flew away. Just got to be more to this than luck.
Lens in use was Nikon 80-200 ED f2.8 and 2 tubes giving an extension of 41.5mm. The lens was initially set at 80mm but as the zoom ring was used to achieve fine focus these are probably at 100mm. Well that is what the lens was at after the wasp flew off. This gave a working distance of 9 inches. Aperture here was f11. Exif if you read it, will show f18 and that is because camera has calculated the light loss from the tubes.
Afraid I have no true idea of the natural light levels as I just set 160sec f11 and manual flash at full bore 18 inches away, with a reflector ( held by Stevie at 45 degrees ). My guess using the sunny f16 rule would put it at about 1 1/2 stops less. Flash was primarily used to allow me to use f11 to give some idea of dof at a sensible point.
It would only be fair for me to point out that the lens in use is although a few years old, a pro quality one. Any true Macro lens would well exceed the image quality here. I would expect edge softness particularly, to be greater with a kit quality zoom. It would be interesting to see any pics from other lenses to see if this is truely a viable cheap way into close ups. Extension tubes costing a lot less than a dedicated Macro lens for those occasional close ups.
Off the top of my head I do not know what lens Christine ( Saphire ) uses, but I have been impressed by the results in her gallery. Hint for a pic here Christine.
Pics here are full frame and crops.
Don