These shots were taken with a modified Canon FD 300mm F4L lens that is fitted to my Pentax K10D.

This shot was taken with the Pentax 1.4XL converter


This shot was taken without the Pentax 1.4XL converter


I am really impressed with the quality of these largely obsolete Canon lenses. If you don't mind manual focus, these lenses are truly exceptional.
This shot is of two blue herons landing side-by-side, again taken with the 1.4XL extender

[jimH]

Nice shots! That lens is working well for you, excellent detail.

[metroeloise]

beautiful IQ!

What is this "Frankinlens?"

How "made to fit?"

MF? I love to MF. That is no problem.

Beautiful IQ!

[8540tomg]

Very impressive Ascara.

Tom G

[gscara]

The Frankinlenses are the old Canon FD lenses. They can be purchased for a song on Ebay and Craig's list, well actually ever since the Panasonic G1 was unleashed, these lenses are slowly increasing in price.

If you only purchase Pentax compatible lenses you have to be prepared to pay a small fortune for long focal length lenses. The SMC Takumar 300mm lens is usually over $200 and has lots of CA and PF. The 300mm K's and M's approach $300 and higher. The A*300mm is over $600. The automatic focus lenses are over $1,000. If you want a 400mm length lens the situation is even worse!!! Yes you can purchase the Tokinas and the Sigmas but you have to be prepared to pay over $500 for decent quality (the at-x's and the APO Macros)

Now look at the particulars. The A*300 lense is not internal focus and, to my knowledge, does not have SD or Flourite elements. This means slow focusing, CA and PF on out of focus elements. The Tokina's have to be be shot at F8 to get decent sharpness and IQ. I personally don't have experience with the Sigmas.

The Canon FD 300mm F4L comes with two UD elements and has no CA and purple fringing. This lens is usable wide open with outstanding results- all the images I have posted were shot wide open. These lenses can be purchased for $200 or less, and yes, you can pay a lot more if you focus on the wrong auction. The Canon FD 300mm F2.8 L's can be purchased for $600 or less. The Canon 400mm f4.5 can usually be purchased for less than $300. The IQ of this abandoned lens family is simply outstanding, especially in those focal lengths where you have to pay a fortune to get Pentax compatible glass.

Try and find a 200mm Pentax macro lens for a reasonable price. If you can find one, be prepared to spend a absolute fortune for Pentax compatibility. This image was taken with a Canon FD 200mm macro that has 1:1 capabilities that was converted to the Pentax mount. While relatively rare on Ebay these macro lenses can be purchased for less than $300.


I love Pentax for their incredible camera bodies. When matched with the obsolete Canon FD lenses the combination can be simply magical!

[metroeloise]

Wow! thanks for the lesson. and these are truly magical...

Conversion? What does that mean? Canon FD lenses? (Excuse my total ignorance ~ I got the gist) But if I search for that phrase I'll find this quality of lens?

[xs400]

Great pics.

Please tell us how you converted the Canon lens to fit a Pentax.

[gscara]

I can describe the process and over the next week or two I will take some images of what I have done and put together a better description.

First the Caveats

• Converting these lenses is likely not reversible. Once you start you have to be committed to the end. You could probably reverse the conversion, but I make use of existing parts when I rebuild the stop-down diaphragm assembly that gives me diaphragm control.
• There is a well entrenched group of Canon FD fanatics that despise anyone that modifies these lenses.
• Most pentax fanatics will think you are crazy because nothing beats Pentax glass.
• You have to purchase a M42-Pentax K adapter plate from ebay. You specifically want to buy one that does not allow for infinity focus, in other words, an adapter that has a thin metal flange. This will take several weeks to arrive.
• None of my conversions are going to win any beauty awards. I don't have access to a lathe or any metal working equipment. My tools are a wooden fret saw with a fine tooth blade, a dremel motor tool, 1/16" thick aluminum plate, epoxy, copper wire, metal files, a couple of clamps, and an electric drill with some small drill bits. I do the entire conversion on the kitchen table in my apartment. In addition, I purchased some UHWM tape from Lee Valley tools to act as a wear strip-bearing, and got my hands on some thin pieces of plywood that I use to sandwich the thin aluminum plate when I saw out the shape that I need. Without sandwiching the thin aluminum it will bend and distort as you saw out the shape.
• Total conversion time takes several evenings. This allows the high strength epoxy to set over a 8 hour period when I create the aperture assembly and fashion the composite mounting plate by epoxying together the M42 adapter plate to the 1/16" aluminum plate.

The process essentially follows these steps:

1. Remove the existing automatic aperture assembly. This is usually the easiest step because you just have to remove three to four small screws.
2. Connect the existing aperture control ring to the existing diaphragm. This process was slightly different on the 300mm F4L and the 200mm macro lens. The macro lens was easier to convert. While the process is essentially similar for both lens and would likely be different for each Canon lens.
3. Mount your new composite adapter plate to the lens.
4. Go and take some pictures and marvel at this new Frankinlens that you have just created!

If you are interested in getting this information, please don't hesitate to PM me and let me know. If I get some requests I will try to steel myself to actually sit down and create the conversion document.

Before I started my first conversion I found some Olympus 4/3 forums where the members had converted a number of FD lenses. Looking at how they did the conversion gave me the courage to purchase the first 300mm F4L lens and give it a go.

If you would like to see more images taken with the converted lenses please check out my Flickr photostream

[kryss]

I can describe the process and over the next week or two I will take some images of what I have done and put together a better description.

First the Caveats

• Converting these lenses is likely not reversible. Once you start you have to be committed to the end. You could probably reverse the conversion, but I make use of existing parts when I rebuild the stop-down diaphragm assembly that gives me diaphragm control.
• There is a well entrenched group of Canon FD fanatics that despise anyone that modifies these lenses.
• Most pentax fanatics will think you are crazy because nothing beats Pentax glass.
• You have to purchase a M42-Pentax K adapter plate from ebay. You specifically want to buy one that does not allow for infinity focus, in other words, an adapter that has a thin metal flange. This will take several weeks to arrive.
• None of my conversions are going to win any beauty awards. I don't have access to a lathe or any metal working equipment. My tools are a wooden fret saw with a fine tooth blade, a dremel motor tool, 1/16" thick aluminum plate, epoxy, copper wire, metal files, a couple of clamps, and an electric drill with some small drill bits. I do the entire conversion on the kitchen table in my apartment. In addition, I purchased some UHWM tape from Lee Valley tools to act as a wear strip-bearing, and got my hands on some thin pieces of plywood that I use to sandwich the thin aluminum plate when I saw out the shape that I need. Without sandwiching the thin aluminum it will bend and distort as you saw out the shape.
• Total conversion time takes several evenings. This allows the high strength epoxy to set over a 8 hour period when I create the aperture assembly and fashion the composite mounting plate by epoxying together the M42 adapter plate to the 1/16" aluminum plate.

The process essentially follows these steps:

1. Remove the existing automatic aperture assembly. This is usually the easiest step because you just have to remove three to four small screws.
2. Connect the existing aperture control ring to the existing diaphragm. This process was slightly different on the 300mm F4L and the 200mm macro lens. The macro lens was easier to convert. While the process is essentially similar for both lens and would likely be different for each Canon lens.
3. Mount your new composite adapter plate to the lens.
4. Go and take some pictures and marvel at this new Frankinlens that you have just created!

If you are interested in getting this information, please don't hesitate to PM me and let me know. If I get some requests I will try to steel myself to actually sit down and create the conversion document.

Before I started my first conversion I found some Olympus 4/3 forums where the members had converted a number of FD lenses. Looking at how they did the conversion gave me the courage to purchase the first 300mm F4L lens and give it a go.

If you would like to see more images taken with the converted lenses please check out my Flickr photostream

Did you get around to providing further detailed account on how you converted FD lens to Pentax? I have an Fd 300mm f5.6 and 85mm f1.8 that I would love to convert.thanks

[misiu_mp]

This is great. I would love to see a more accurate description of the process or some pictures. Links to those olympus forums would be helpful too.

[photocanadian]

I have posted some pointers for a basic (but fully reversible) Canon FD to Pentax-K lens conversion which produces lenses that work very well in AV and M modes at:

https://www.pentaxforums.com/forums/lens-clubs/64271-impossible-lens-club-9.html

Let me know what you end up with - there are many ways to skin this cat.