conurus

mOnAmis · Joined: 14 Sep 2006 Posts: 29

I note what you say about soldering the conductive film in the instructions. Why does it need to be soldered. In devices that I have dismanltled in the past that use this type of conductor they either are soldered using a soldering machine or they are inserted into a slim socket. Why not put such a socket onto your converter?

conurus · Posted: Thu Sep 14, 2006 6:07 pm Post subject:

I have seen that construction in other brands - a flex circuit plugs directly into a surface-mounted flat-cable socket. The flex circuit can be unplugged that way without soldering.

Unfortunately, Contax N lenses do not use that kind of construction. Instead, either the flex circuit board is the same as the main CPU flex circuit board, or the connector, if it exists, hides very deeply inside the lens. I have never diassembled beyond just the mount to figure out which way it is.

mOnAmis · Joined: 14 Sep 2006 Posts: 29

The lens I am currently concerned about is the 17-35. How close together are the conductors on this flex board? How thick is it? Do you know what the melting temp is of the solder or do you have a suggested soldering iron temp?

Is the lens to sensor/film plane distance any different with the N lenses and Conurus mount than it would be with and ND or N1 or in other words are they going to behave optical in exactly the same way as they do on COntax cameras?

Have you tried any/all of these lenses on a 5d or 1DSmk2 yet.? If so what are the results like?
Soryy for the barrage of questions.

conurus · Posted: Thu Sep 14, 2006 9:07 pm Post subject:

Well, the 17-35 version is still under development. There are no install pictures yet but I will try to describe it the best I can. In a nutshell, we desolder and remove the black plastic ring of the lens with the 10 gold-plated connector pins, and solder a small circuit board in its place. The 10 gold-plated pins are spaced rather wide apart, so this is regular thru-hole work. You will need braided wick or a suction pump to remove solder. Either way it has to be rated ESD-safe.

I have not measured the temperature required to do this, but it would be around 650 degree F or 340 degree C. Sometimes, a higher temperature may actually be safer, but I will give you the final temperature after more testing.

Your second question is probably whether the backfocus distance (defined as the distance from the rear element to the film/sensor plane) is maintained after the conversion. As can be inferred from step 2e of our installation instructions:

http://en.conurus.com/install.html

The difference should be exactly 4.00mm. In practice, there is no such thing as "exact", but by putting in the right combination of shims, we need to be as close to 4.00mm as we can. If step 7 makes sense to you, you will see that optically the lens will behave in the same way before and after conversion. Given that all N mount lenses are autofocus lenses focusing beyond infinity, we should not be obsessed with tiny differences so long as it is under 0.03mm.

We do not have a 5D or a 1Ds mk II to try it out. However, some of our customers reported success on those two models.

mOnAmis · Joined: 14 Sep 2006 Posts: 29

Thank you very much for your consise reply. When do you think the 17-35 will be ready or have you posted this already?

Does anyone have any examples of the output of a 5D or 1dsMk2 that they would be willing to share?

Although your instructions are great may I suggest that you create a technical drawing of the measurements in order to avoid doubt.