Nomad Z
Well-known
Brian, any clues on how to get the aperture blades out of an I-61? I've decided that the mechanical slop at the mount of my example will always annoy me, so it's getting turned into a lupe. I've got the optical module out, and have removed the front and rear elements. It seems that the blades come out through the front, but there is another element still inside which is in the way, and with no obvious means of removing it. Is it a friction fit or something?
I have not taken one of these apart in a long, long time... I seem to recall the middle group being glued in.
I ended up converting my I-61 to Contax Mount. I know what you mean about the slop on the focus mechanism. The optics are great, that mount- not. The thread of the optics module is that the retaining ring screws into is the same as the threads of the J-8. Not you make me wonder if it could be remounted in a J-8 LTM focus mount.
I ended up converting my I-61 to Contax Mount. I know what you mean about the slop on the focus mechanism. The optics are great, that mount- not. The thread of the optics module is that the retaining ring screws into is the same as the threads of the J-8. Not you make me wonder if it could be remounted in a J-8 LTM focus mount.
Nomad Z
Well-known
If it's glued in, then in it will stay. I since unscrewed the little pin that's used to adjust the aperture, and moved the mechansim hard over to wide open, and it seems to have decided to stay in that position, so removal doesn't seem neccessary.
Agreed on the mount - it's like a brake disc between two pads. Mine had slop in it, until I worked out that I could machine a little material away and reduce the slop. However, I must have taken a smidge too much off, because the focus ring was binding when the three screws were tightened. Back them off a little, and it would free up. I could have done a little more machining of whatever the other surface was, but I realised that it would wear eventually, and the slop would come back. Not worth the hassle, really, which is a shame, because they seem to have a reputation for very good optics. Still, makes for a rather nice lupe at a bargain price - nice and sharp across the field.
I've been fiddling around, trying to find something that could be used to support it at a suitable distance for viewing negs, and for use with my large format camera, hopefully taking advantage of one or other of the threaded parts to make it focussable. Looked at bits of plastic plumbing with a view to incorporating the bezel that is around the front element of the original lens, but that thread is a bit coarse and feels like it will slacken by itself.
Then I spotted a cheapie lupe that I've had for years and tried the rear retaining ring in that - it was a perfect fit, so I popped the plastic lens out and jammed the I-61 ring in its place. Turns out that the distance it holds the optic from the surface is just about spot on, and the fine thread on the retaining ring makes for easy focus adjustment. The photos below show the result so far.
Retaining ring in the plastic body of the cheap lupe, with the I-61 optic beside it.
The two parts assembled into my bargain lupe.
Agreed on the mount - it's like a brake disc between two pads. Mine had slop in it, until I worked out that I could machine a little material away and reduce the slop. However, I must have taken a smidge too much off, because the focus ring was binding when the three screws were tightened. Back them off a little, and it would free up. I could have done a little more machining of whatever the other surface was, but I realised that it would wear eventually, and the slop would come back. Not worth the hassle, really, which is a shame, because they seem to have a reputation for very good optics. Still, makes for a rather nice lupe at a bargain price - nice and sharp across the field.
I've been fiddling around, trying to find something that could be used to support it at a suitable distance for viewing negs, and for use with my large format camera, hopefully taking advantage of one or other of the threaded parts to make it focussable. Looked at bits of plastic plumbing with a view to incorporating the bezel that is around the front element of the original lens, but that thread is a bit coarse and feels like it will slacken by itself.
Then I spotted a cheapie lupe that I've had for years and tried the rear retaining ring in that - it was a perfect fit, so I popped the plastic lens out and jammed the I-61 ring in its place. Turns out that the distance it holds the optic from the surface is just about spot on, and the fine thread on the retaining ring makes for easy focus adjustment. The photos below show the result so far.
Retaining ring in the plastic body of the cheap lupe, with the I-61 optic beside it.
The two parts assembled into my bargain lupe.
This is my solution to the I-61 focus mount...
Collapsible I-61 in Contax Mount.
On the slop in helical: I use heavy vacuum pump grease under the ring. You know the one. It works, helps control the slop. I do not like working on I-61's, they can drive you crazy. Comes apart, goes together "not quite right". Have to fiddle with grease.
Collapsible I-61 in Contax Mount.
On the slop in helical: I use heavy vacuum pump grease under the ring. You know the one. It works, helps control the slop. I do not like working on I-61's, they can drive you crazy. Comes apart, goes together "not quite right". Have to fiddle with grease.