[Update on September 23, 2005]
I have sold off many of my lenses with duplicate focal lengths, and only keep the ones I like best. Even so, I still have more than 20 of them, half of them are standard lenses :-)

[June 8, 2005]Update:

I now have over 20 M42 lenses. Believe it or not, I use all of them, some more often than others. The 50mm , 35mm and 28mm lenses are used more often then the long lenses.

After using many manual focus lenses with my 10D and the split focus screen for a few months, and especially only manual lenses the last few weeks, I am totally at home focusing by hand. Sure, I am not as fast as autofocus with moving objects, but in many situations manual focus is fine. I feel like I am back to my Pentax Program Plus days again.

If you have any questions about using screw mount lenses on digital cameras, please drop me a line.

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The manual focus lenses are my fun lenses. It all started when I read a forum and saw that people could use old lenses on the Canon EOS body, and I did some research and found that the Canon EF mount is one of the most adaptable mounts in the world. With a proper adapter, you can mount many manufacturer's lenses on it, including the Nikon (not the new ones with no manual, mechanical aperture settings), Leica, Pentax Universal Mount (M42 or Screw Mount), Contax/Yashica, Olympus, and others.

For most people, the major advantage of using old, manual lenses on digital cameras is the price, and for others, it's the only way to use their favourite lenses on camera bodies which are no longer available or they want to use them on digital bodies. If you have been shopping for a quality prime lens, you would no doubt be shocked by know how much new, quality lenses cost. For example, a 50mm F1.4 Canon lens would cost about $500 Canadian, whereas an older screw mount 50mm F1.4 lens can be had for around $40. The quality of picture these lenses produce is excellent, considering that many of them are 30 or 40 years old.

In the 60s and 70s, most of these older lenses were created like an object of art, and there are usually some very interesting stories, and backgrounds behind those old lenses. Comparing the construction quality, and the materials used, the modern lenses seem inadequate. My Canon 28-70 F2.8L lens costs more than $1000, and yet it is not as well made, or focuses as nicely, as a 40 year old Pentax Takumar. As Mike Johnston mentioned in one of his Sunday Morning articles, he quoted a Japanese engineer as saying if today's lenses are made like the old Takumars, it would have cost more than $1000 for a 50mm lens.

I owned a Pentax Programm Plus for more than a decade, and I sometimes miss mechanical feel of those old, yet well made lenses. Yes it's tricky to focus with the stock focusing screen, but fortunately, the Canon 10D (and the 300D)'s screen is very easy to remove. I used a Nikon FE screen, which seems to be the exact thickness of original 10D screen. I cut the Nikon screen to the same size as the Canon screen and replaced it. It works fantastically. Manually focus is not a chord at all with the right focusing screen, if used under F5.6, as the split screen would darken by this aperture. As a matter of fact, with the split screen, you can see that when autofocus lenses are used, the focus is not always correct as shown by the split screen, although the accurracy is better than I thought. It's spot on most of the time.