Camera lens stop down rings...another question

[Vixen4eva]

Helllo

Probably a silly question but i`m going to ask it anyway...

When using the rings do you leave the lens wide open or adjust it using the camera settings to match the desired f ratio? I`ve just purchased a Canon 200 mm f2.8 USM and was using it last night for the first time at f4 (using the rings) but the camera was still set at f2.8.

Thanks
Alan

[symmetal]

Leave it fully open. If you adjust it to match the ring you run the risk of the iris blades being in shot again which defeats the purpose of using rings. The camera is in fully manual mode so its internal exposure calculations aren't used.

Alan

[Vixen4eva]

Thanks Alan just wanted confirmation....

Regards

Alan

[ollypenrice]

Yes, keeping the blades out of the path is the whole point.

Olly