Canon FD 50mm f/1.8 SC Six apperture blades

[theo_bern]

<p>Recently I bought an F1n to use it as spares.<br>

It had attached a FD 50mm f/1.8 Breech lock that had oily apperture blades and when I opened it to clean the blades I found out that instead of 5 blades this one had 6 Blades?<br>

Lens # 1066400 Prod. Code P1211.<br>

Is that possible? Also it has the lock button on the back of the lens.<br>

Thank you.</p>

[User_502260]

<p>That's the normal number of blades for the lens you have. Some people do not like the 50/1.8 New FD because it has only five blades. Each manufacturer has a different idea of how many blades a lens should have and whether that should be an odd or even number. Most Nikkor lenses after a certain date had seven blades rather than six. A few high end lenses had nine blades. Once you get past nine or ten it becomes difficult to open and close than as quickly as would be required when using a winder or motor drive. I just looked at 50/3.5 Zenzanon PS for my Bronica SQ cameras. It has only five blades but the blades are curved and the out of focus rendition is pleasing. My 200/2.8 Canon New FD (1st version) has eight blades. Nikon thought an odd number of blades would produce more pleasing out of focus rendition. After a certain point it's a matter of taste. The black front 50/1.8 FD SC with the aperture lock switch on the back is my favorite of the slower Canon FD standard lenses. </p>

[gordon_yee]

<p>There were two versions of the breech lock FD 50mm f/1.8 S.C. lens. Check this earlier thread:</p>

<p><a href="00Qciq">http://www.photo.net/canon-fd-camera-forum/00Qciq</a></p>

<p>This change is documented on the Canon Camera Museum site, though I don't recall any formal announcement by Canon in 1976 when the change was made. It was part of the trend to make lenses smaller, lighter and cheaper.</p>

[theo_bern]

<p>Jeff and Gordon,<br>

Thank you for your replies. The reason I asked was because I have two copies of the 50mm breechlock and both have 5 blades. Now it's clear to me. I will have to try it to see the extra blade effect on the bokeh.<br>

Thanks again.</p>