Originally posted by Lowell Goudge someone commented that this may be also a function of focusing distance, does the aperture change if you focus to infinity and read F4? I did not see a response to that. Also how close to 70 does it get to and remain at F4?
I would be interested. it may be they are playing on permissable tolorances, and if so, that would be too bad, i.e. at 65 its F4 but at 70 it is 4.5 . Also can you tell us the filter diameter, and the diameter of the front element.
simply put an F4 lens at 70mm should be a diameter of about 17.5mm only.
Umm.. I responded with... " let me check.. this happens both ways ;(." So it happens both ends of focus ;/. Whether it is macro or not also. Umm... filter diameter is 72mm I believe...
I can't really explain how close to 70 does it get and remain at f4 because anything about 50mm is shown as 50mm on the data. So... I'm just going to take some pictures to show you guys. Please excuse the Sony P&S ;P.
Got some pictures up.
Excuse the blurry.
At F4.5
Here are the Focus ring adjustments that keeps it at F4.5 still
These two are about the threshold where they change from 4-4.5
At 70mm
This is just when it's below 70mm to show you it can actually go to F4.0
Sorry ;( going to sleep... and going away first thing in the morning... so might not be able to reply to the thread. Sorry!
Last edited by NecroticSoldier; 06-24-2010 at 08:29 PM.