Fed-50 Lens at f/3.5

[cmdrzed]

Hi all, I recently purchased a Fed-50 collapsible lens from fedka. The lens looks great (it's clean, smooth, and has perfect glass). I have been shooting with it for a couple of days now and I seem to have a problem with f/3.5. The lens is mounted on my M6 via a 50mm adapter and photos taken at apertures >3.5 look great. The ones taken at f/3.5 don't look too good (maybe I am expecting too much?).

It seems that the lens does not focus on what I think it is focused on. Earlier today, I shot a portrait at f/3.5 and the person was blurry but the background became sharp at some point. In other photos taken at f/3.5 the entire image is blurry. I'm fairly certain its not because of camera shake. Any ideas? Also, does anyone have examples taken at f/3.5 that they can post for comparison. I will post an example soon (once the negatives dry).

Thanks.

 

[wolves3012]

Early FED 50s were not necessarily set to the standard 28.8mm lens-to-film distance, they were matched to the body. Later (coated) ones shouldn't suffer that problem but maybe your adapter is upsetting things? I have 2 of them (uncoated) but they "park" inconveniently across the RF window on my IIIC so I've not used them on it. I've used a couple of Industar 22s successfully on the IIIC though.

 

[cmdrzed]

I was thinking that the adapter could be causing problems too. One other thing is that maybe the lens was not extended properly. I am going to shoot another roll later to test this.

 

[cmdrzed]

Well, here is a test shot that I made earlier today. It illustrates the problem I was describing. Focus was placed on the rightmost purple flower but as you can see it is not in focus. I read on a site that spacers can be inserted into the lens to set the distance so it gets correct focus. This process seems rather difficult. Any suggestions ???

Fed 50 Example

 

[cmdrzed]

Posted in the event someone out there does stupid stuff like I do 🙂

I solved the problem. It was a user error problem and I feel completely moronic for it. I removed the lens for inspection and realized that there is a locking mechanism when extending the barrel. It seems that it was not 'fully' extended when I thought it was. The barrel needs to be rotated a bit then it will extend a bit further and lock when twisted in the opposite direction. Geez. The freshly developed negatives look good and I consider the problem corrected. :|

 

[Murray Kelly]

Glad to hear you got out of it lucky. I had a Fed with the same lens and the seller told me as I walked out the door that it was a good portrait lens - it was a bit soft. He loved the pictures he took of his Mom with it.
With the first roll I found that it was miles out of focus. At 6' a picture of my wife and her cousin was terrible until I noticed the buildings in the distance were sharp.
It took a 1.6mm spacer to fix the lens and now it is fine. I wish it had only been a simple matter like yours was to fix! I don't know how he ever put up with it, the way it was.
Murray

 

[fanshaw]

I have a an Industar-50 which cannot be locked after extending it. A manufacturing defect, I suppose.

 

[cmdrzed]

That's odd. This was my first collapsible lens so I assumed a simple extension of the barrel would suffice. I was beginning to think that there was something wrong with it. It is a swell lens