FD 35-105mm Focus Problems?

M. Gilden

M. Gilden

Canon DSLR Moderator
After hearing glowing reviews of the FD 35-105 F3.5 (constant aperture), I decided to pick one up from KEH. Price for bargain quality was right, and picked up a cheap jiakgong FD to M43 adapter (coming from an EOS world, this was my first FD lens).

I'm noticing that the lens does not seem to reach infinity focus. I understand that this is normal on when using adapters on bigger SLRs due to the flange distance, but adapters for mirrorless cameras like the M4/3rd mount should be a perfect fit.

The question is, is there something wrong with this particular lens or the adapter? While adapters range in build quality, I have never heard of one causing focus problems.

I've seen others on the forum mention Jiakgong's adapters, and I like the option to attach a tripod mount to the ring for heavier lenses:
http://www.ebay.com/itm/33056898581...NX:IT&_trksid=p3984.m1497.l2649#ht_3179wt_917

Could it be the lens? I wish I had another FD to try, just to see if it can focus to infinity. I'm not near a camera shop at the moment and none of my colleagues use FD, so I'm really not sure what to think at this point. Wondering if anyone out has any input?
 
Ok wait, there's more info to add:

I noticed that focusing on near subjects is difficult as well. I know I can use the macro mode on this lens and go closer (as long as I'm willing to keep the zoom at 35mm), but without it I can't seem to focus on anything closer than around 3 ft. The markings on the lens say I should be able to hit focus at 1.5ft, so I'm pretty sure something is off here.
The focus wheel seems to turn smoothly, everything else about the lens appears to work great, but I feel like I'm not hitting the full range of focus, and falling short on either extreme.

If it were an adapter problem caused by inaccurate flange distance, the focus range would be shifted. In other words, I would never be able to reach infinity because it would past the end of the focus wheel, however I would hit near focus sooner in the other direction, and actually be able to focus closer as a side effect. At least, I think this is how it works unless I'm missing something fundamental here.

So, if I'm not able to reach either extreme of the focus range, it must be some fault in the lens, right? Perhaps one of the elements isn't moving or something?
 
I would lean towards the lens as the problem, especially since you experiencing problems at both the minimum focal distance, and at infinity.
 
That's what I suspected, good to hear I'm not alone in my theory.

Time to find out how KEH handles return/exchanges? :)
 
it may (or may not) be the adapter; I use ciecio's one and it focuses to infinity with my 35-105.

as for close focusing, you got it a bit wrong - it says 1.5m and 5ft ;)
 
Interesting- I guess I may have been looking at the wrong number.
So if I'm managing to focus at 3ft, I'm actually getting closer than I'm supposed to be able.

That could be a problem with the adapter, however if the problem is indeed related to the flange distance, I should also be able to overshoot infinity focus on the other end of the focus wheel, shouldn't I?
The science of optics can get kind of confusing, but if the entire range of focus has been shifted closer wouldn't I be able to reach infinity closer on the wheel as well?

Right now, I can't seem to reach infinity- I turn the wheel all the way around, and it gets close but seems to stop just before reaching that point. Does that make sense? Am I still leaning towards a lens problem versus an adapter one?

I'm going to try and get my hands on another FD lens and see if I can reach infinity on it, but it probably won't arrive for another few days.
 
M. Gilden said:
So if I'm managing to focus at 3ft, I'm actually getting closer than I'm supposed to be able.

That could be a problem with the adapter, however if the problem is indeed related to the flange distance, I should also be able to overshoot infinity focus on the other end of the focus wheel, shouldn't I?
Click to expand...

Not if the entire focusing range has "shifted" towards the close up end of the lens. In that case you would indeed run out of focusing ability short of infinity.

Sounds like a flange distance issue to me.
 
stoneinapond said:
Not if the entire focusing range has "shifted" towards the close up end of the lens. In that case you would indeed run out of focusing ability short of infinity.

Sounds like a flange distance issue to me.
Click to expand...

Ah. I guess that makes sense as well. Bugger. I will have to try it with another lens to confirm when I can. Strange though, I know build quality was suspect on the cheaper adapters but I would be really surprised if the flange distance was not consistent- that's kind of hard to mess up with these adapters. Also, I know other forum members have used jiakgong adapters successfully. I guess it could really be either.
 
Drat. Just found out the other lens I'm waiting on didn't ship until today, probably won't have anything to test until next week. Would really like to get to the bottom of this already.
 
UPDATE:
Got my hands on a 135mm F/2.8 in FL mount today. Tried it out, and managed to focus to infinity as well as what appears to be the appropriate macro length. So, I'm guessing this particular lens is the problem and not my adapter. I will contact KEH tomorrow and see about an exchange- otherwise, the 35-105mm is really a very nice lens. I actually used it today despite the range issues, as a second angle during an interview.
 
You must log in or register to reply here.
Back
Top