----- Original Message ----- From: "conestoga304" <[EMAIL PROTECTED]> Sent: Sunday, November 30, 2003 3:02 PM
> Folks > > I need your help - please read explanation and request! > > I am in China and may have the opportunity to visit a museum later in > the week. Some of my photo gear was packed in the checked baggage and > I am concerned that it *may* have suffered shock damage - not on the > flight but during the taxi ride later (roads are very rough). The > lens was well packed, but... > > The particular lens in question is the old EF 28-70 f3.5/4.5 Mk2 - > it's not an 'L' lens but it is really quite good - or at least was. > > The possible problem is with the aperture diaphragm. When the lens is > not powered (i.e. disconnected from the camera or the camera > indicates 'wide-open' f3.5 or 4.5 depending on focal length) I would > expect the petals of the diaphragm to be fully retracted and not > visible. This is certainly the case with the other two lenses that I > have with me. > > This is not the case with my 28-70 - rather, in the above state I can > see the petals (a little bit) and I'm not sure that this is normal. > > Apart from this the lens 'seems' to function as you would expect - it > focuses, the diaphragm opens/closes when CF11 on my EOS10 (depth of > view preview) is selected, I hold down the partial metering button > and adjust the aperture in Av mode. > > It's just that I don't remember seeing the petals before - not that I > have really ever looked. But the sight of them struck me as 'unusual'. > > Request. Would some kind soul please take a look at their example of > this particular lens and let me know what they see with regard to the > diaphragm. > > Does anyone maybe know of a simple test to verify, or give greater > confidence of, correct operation (short of getting films developed). Steve, If what you are seeing is as though the lens were stopped down ever so slightly, then you need to check this at both ends of the zoom range. If it is not visible at one end then it's likely that nothing is wrong. Some zooms are designed this way. HTH CraigZ * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
