Canon nFD 400mm/2.8 L conversion to EF mount

ZoneV · Expire: 2011-12-02

The FD 400/2.8L is one of the lenses I convert at the moment - I am not ready, but the work before me seems not to problematic.

For this conversion and my FD 85/1.2L I thought about a better option to make the linkage between iris ring and the iris inside the lens.
My last conversions seems much as tinker work - not like something made from an engineer Laughing

I work at the moment at a new system that seems to work for different New FD lenses. A disk with flange holds into the iris ring, and on the flange I could assemble the crank to the iris like in the longer tele lenses (300/2.8, 400/2.8, 500/4.5), or a holder for the iris crank like in the Fd 85/1.2L.

This is the iris ring with the coupling flange:

And here as a first prototype to show the coupling flange with the crank for the 400/2.8 - with slits for the screws it should be screwed together maintaining some clearance for adjustment of the open iris:

And here the parts:

The now used M42 mount adapter could hopefully be replaced with a special made EF mount ring which also corrects the flange back distance - in future. I suppose that with such an FD mount plus the coupling flange New FD conversions would be much easier for me.
At the moment I machine these with a mill and mini lathe, but I start thinking about a small order at a metal supplier if the idea works out well enough.

I hope that I get further this weekend - I could not use the mill in the evenings, much to noisy for the neighbours.

Jesito · Expire: 2015-01-07

Great!.
Thanks for sharing!
You are a brave man, I don't dare to modify any of my FDs... Sad

Regards.

Jes.

ZoneV · Expire: 2011-12-02

Thanks!
The FD lenses are not easy to convert, but I like to pioneer things I do not already have in my DIY Photo Directory
http://4photos.de/camera-diy/index-en.html

ZoneV · Expire: 2011-12-02

On Saturday I finished the louder work on the nFD 400 conversion, yesterday evening I put all the parts together - for the first time.

At about midnight I took the lens on my camera, and tested at night if I get more or less infinity ~ 100 meters distance. Not a real test, but I had some space to go for further distances. Now I have the 6 kg lens with me, and want to test it at lunch time - hope the police don�t disturb me here in the city Smile

My new parts seems to work well - as far I could tell that after this few hours of assembling and doing some first fine tuning.

One of the main parts for the New FD 400/2.8 mount conversion is a ring that holds the iris into place. This ring could be seized inside the outer tube, and the iris could be screwed on this ring. And best: For the alingment of this ring longer screws could be used to help with this task. Here a picture showing the longer screws while mounting this ring inside the tube.

Futher fine tuning is needed, at f/4 at the iris ring the iris is still full open. And the crank for the iris scratches the filter inside the lens, I have to bend the crank a bit.

This conversion is full reversibel. Only small paint loss in the inside where the screws of the iris holder ring scratched the tube. No FD parts are sacrificed. But a lot of machine work was needed.

At the moment I have only a German page about this work, with few images and text. More to come soon.
http://www.4photos.de/camera-diy/Canon-NewFD_400_2.8-EF-Bajonett-Konvertierung.html

marty · Joined: 09 Apr 2009 Posts: 767 Location: Italy

Excellent job.

Cheers, M.

ZoneV · Expire: 2011-12-02

What a crappy weather :-/
There are times with sunshine - but I see these seldom moments from the office, sitting in meetings.

So now only first test images through this lens @2.8, made inside with some extension tubes:

Link to original size:
http://www.4photos.de/camera-diy/Image-FD-400_2.8.jpg

Link to original size:
http://www.4photos.de/camera-diy/Test400-2.8.jpg

greg · Expire: 2012-12-03

I always like to see such handwork, good job.

ZoneV · Expire: 2011-12-02

Now I used the lens for some more suitable objects - birds, nature and farther away objects.
Great!

But there is some ~ dust in the lens, and I have to check if I need more velvet inside for stray light reducing. Sometimes the contrast is not as high as I expect.

Here a picture with 2x teleconverter on the lens, I think it was a Kenko TC.

Bird von Time-4-Photos auf Flickr

Kr�ne im Hamburger Hafen von Time-4-Photos auf Flickr

trifox · Expire: 2014-05-29

hmm.

I am just curious about the holes in the EF adapter -- they're very close to the middle...

In other words - if you have holes close to the outside diameter - the whole mount is stronger - especially when fitting such a heavy lens...

tf

ZoneV · Expire: 2011-12-02

I have used the original FD hole position. No pictures available in the moment.

The screws are strong enough to hold the 6 kg lens hanging at the camera - and the camera hanging on my neck Smile

I have a further strap on the lens, but that was loose.

trifox · Expire: 2014-05-29

ZoneV · Expire: 2011-12-02

Ed Mika

Zone V, great work as always, especially for not harming the original gear. An FD300 2.8 is on the market near my house (and my EF 300 2.8IS is my favourite lens) and I am considering getting it and seeing if I can come up with a conversion kit like my FL 55 1.2 CNC machined from brass since its such a nice material to work with and stronger than aluminum.

1. Do you think there would be much interest for a maybe 200 dollar level conversion kit for this lens and
2. how different are the 300 2.8 and 400 2.8 lenses, would a common kit work for both perhaps?

My EdMika 0.75 works great for the 500-800 lenses but it would be nice to get infinity on the beautiful 300 and 400s for someone who is not as skilled as you and without access to machining equipment. I'm also starting to look at a kit for the 85 1.2 but I'm not sure about which version. The nFD one appears the most common and I have one already but the breech lock may be easier to engineer.

-Ed Mika

ZoneV · Expire: 2011-12-02

Hi Ed - thank you!

The nFD 300/2.8L and 400/2.8L are very similar - but not 100%.
During my work with the 400/2.8L I thought a bit about how I could make things easier.
My result was primarly the nFD iris coupling part, which I could customize with my tools for many or even all original Canon nFD lenses - and make my conversion life much easier.

Furthermore a special nFD-EF mount part with proper thickness and holes could help much for all nFD lenses.
For that part (without all optimization) I have a quote - but I am not sure if I want to got this not very cheap way - need to buy for some hundred Euro.

I did not take a closer look onto your great conversion kit, but I suppose that for the conversion of the 300 & 400/2.8 L one has to open the lens behind the iris, and with long screwdriver open the mount parts - either through the open iris blades, or take the iris assembly away. If one open the false screws, on has the iris opened fully - some people might fear this.
On one of the lenses I need WD 40 oil to get that screws open, I think there I feared the screwdriver could break because I have to use brute force to press it into the screw head.

Not sure about these operations, or if probably a different way is possible. If I remember correctly, I would not recommend this partly disassembly for someone without lens tinkering experience.

For the nFD FD 85/1.2L: For the reversible way I needed a lot of disassembly of the back end, to get the parts away. For non reversible work as common, this is not needed.
Here again, I am not sure about possible easier ways.

As soon as such a kit for 200 USD would be available many of the people owning one would think about that conversion - for own use, or for better selling price.
But in my opinion most photographers didn�t dare to open lenses, couldn�t estimate the number of those owning or buying this lenses + having the guts to do a not very simple conversion - even with ready parts and a description.

Ed Mika · Posted: Sat Sep 03, 2011 8:38 am Post subject:

After we finish the EdMika TS 35mm 2.8 EOS conversion kit we are currently developing I plan on trying to make a reversible universal adapter kit for both the FD 300 and 400 lenses. Thanks for the insight, I am aware that many people will be afraid to do it themselves but with good instructions and no need for custom work or machining I think plenty will be willing to try.