Bought a 21mm f/3.4 Super Angulon lens for $750

[sc_rufctr]

Does this help?

Useful video IMO.

https://www.youtube.com/watch?v=t4H5h_ZDZHE&list=PL4wLh5VR2NtKc5ridRZNlFE23BHjd8m6r&index=6

 

[astro8]

Thanks for the links Peter and Jerevan. I have the lens cemented again at the moment temporarily with clear acrylic and have been testing for sharpness across the frame and flare. All seems good to me.

I was racking my brain for a while there as to how to get the three elements in perfect alignment for re-cementing. They more or less free float on top of one another until cemented in place.

I have cnc machines and laser cutters at my disposal with which to to make a jig out of acrylic block, which wouldn't be too hard. Then it dawned on me that I could glue the elements together and align it all by spinning it before the 'glue' had set, much the same way as truing a bicycle wheel. It was pretty easy whilst looking through an 8x magnifier to see the tiniest discrepancy in misalignment.

I have some UV optical cement in the post for the permanent fix. I strongly suspect the reason the rear element was so hard to remove is because it was previously put back askew in the housing and the 'technician' either couldn't or be bothered to remove it to put it right. The tolerance is so tight that I have had it stuck a couple of times myself. I eventually removed it by heating the housing to expand it just enough to let the element fall out. It is all adding up as to why my images were so blurry too, as the thing could never be focused properly. My previous SA was superbly sharp in the center.

Rear group separated...



Before...



After...



A couple of pics just to give an idea. Focus is spot on. It will be interesting to see the what difference the optical cement makes. I'll post some 'proper' pics once I have it UV cemented.

 

[Jerevan]

Just remember that the Canada balsam is much more forgiving, should you make a mistake - you can take it apart easier and reglue again if need be.

 

[kbg32]

It's hard to believe that I just bought a 21mm f3.4 Super Angulon lens, complete with hood and viewfinder, for $750. It was listed on Craigslist and the asking price was $800. I did manage to bargain him down a bit. I told him I really wanted a later serial number version of the lens, which is true. Eventually we agreed on $750 and I gave him my hard earned cash after inspecting the lens for the usual problems (e.g. fungus, haze, dust etc). Everything seemed fine to my untrained eyes. Even the viewfinder, complete with its own case, was in great shape.

Now all I have to do is to go out there and use it.

Ellen

I hate you.

 

[astro8]

Just remember that the Canada balsam is much more forgiving, should you make a mistake - you can take it apart easier and reglue again if need be.

Thanks Jerevan. Something tells me to heed your advice. I've located some locally. I'll post my results.

 

[astro8]

Quick update for those interested...

I've ordered the Canada balsam but in the mean time I have re-cemented with the acrylic. This was a better job as I can see that the lens group is now crystal clear. Upon taking a few test pics, I am quite content with leaving it as is for a while.



What I'm most pleased with is getting rid of the flare. It was really bugging me.