f51 from a f32 lens - How's this possible?

[deckcadet]

Macro lenses change their 'effective aperture' as you focus closer. This effective aperture gets smaller as most macro lenses actually change focal length too as you focus close. Some lenses do not report this, but all Nikon brand macro lenses and some 3rd party ones like your Tamron do.

[PhoebeG]

Harrison,

Thanks, good info. Any thoughts as to why I see so much "junk" (dust, etc) in my images when the aperture gets real small? I had'nt noticed all of that stuff before I got this lens.

I'm tryin to track down a cleaning kit (sensor swabs and the e2 liquid), but had to order it through my local photo store, not available for shipment to me from the usual internet sources.

Phil G.