20d Adapting other lenses to fit

[Fingers]

I have been looking at the cheep macro options for my Canon 20d and as I have one of these in the house

http://cgi.ebay.co.uk/MC-Pentacon-1...goryZ707QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I then came across an adapter that fited the lens the right way round onto the body.!!

http://cgi.ebay.co.uk/M42-Lens-to-c...ryZ30059QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

A perfectly good quality prime lens for vertualy no spend, then the options of same screw fitting lenses bolting onto my 20d. Sounds great. Yes it will only work in manual but I use mine like that any how.

AND THEN,

This open the possibility of adapting all sorts of very good quality cheep lenses?

BUT are there any pit falls with this ?

 

[Garbz]

Depends on the mounts. If the adapter is thick enough it will cause the lens to lose infinity focus unless they place a glass element in the adapter to correct it. In this case you suffer a quality hit and an increase in focal length.

 

[Helen B]

One of the great things about the Canon mount is that the FFD or 'flange focal distance', also known as 'flange focal depth' or 'register', is one of the shortest in the business. This means that many other lenses can be mounted to a Canon while maintaining infinity focus. Some people use Leica R lenses on Canon bodies, for example.

Canon 44.0 mm
Leica R 47.0 mm
M42 45.5 mm
Nikon 46.5 mm

Therefore the M42 to Canon converter flange needs to be exactly 1.5 mm thick to maintain infinity focus. This is quite possible, and it is a useful feature of the Canon mount. The 'throat', or diameter, of the Canon mount is also comparatively large, making adapters easier to make.

Best,
Helen