p.6 #3 · lens repair, modification and disassembly guide thread
These aren't really modifications - just just getting the dust out on mostly current Canon lenses. Might be useful to someone wanting to open these up, though:
p.6 #4 · lens repair, modification and disassembly guide thread
Hi All,
I'll be paying more attention to this thread, now that I finally have a G28 on the way. As mentioned upthread, I elected to use a MD 50/2 donor lens due to the smaller diameter and size, but the aperture ring is plastic.
Sebboh, So it looks like you have done a G45 already and now a G28. The 45 looks to have some type NEX adapter, maybe a Leica M bayonet?
Are you planning a M bayonet on the G28? If so, I suppose you would get proper infinity focus on a Leica M camera? minus the rangefinder focusing of course.
p.6 #5 · lens repair, modification and disassembly guide thread
JimBuchanan wrote:
Hi All,
I'll be paying more attention to this thread, now that I finally have a G28 on the way. As mentioned upthread, I elected to use a MD 50/2 donor lens due to the smaller diameter and size, but the aperture ring is plastic.
Sebboh, So it looks like you have done a G45 already and now a G28. The 45 looks to have some type NEX adapter, maybe a Leica M bayonet?
Are you planning a M bayonet on the G28? If so, I suppose you would get proper infinity focus on a Leica M camera? minus the rangefinder focusing of course....Show more →
yes, m-mount for both lenses as it allows me to use helicoid adapters on them for an even better mfd as well giving me more latitude as to which future cameras i use them on.
one issue for me is that i don't presently have an m-mount adapter that hits infinity dead on with leica lenses so i can't tune infinity as well as i would like. hopefully at some point i'll be able to borrow a leica m so i can set the infinity stop precisely where it should be. does anyone know if the gxr flange distance is as consistant as leica's?
for what it's worth, i examined an MD 50/2 at some point while trying to determine a good donor lens and it seemed to have internals that were less conducive to the conversion than the MC 55/1.7 in addition to the poorer construction. can't remember exactly what the issue was though.
interesting, you keep the front part of the contax helicoid attached to the optics.
now i remember why i thought the MD 50/2. wouldn't be that good – i was considering it for the g45 which has to large a rear element to fit through that rear opening and i thought linking the aperture mechanisms between the two lenses would be difficult.
p.6 #8 · lens repair, modification and disassembly guide thread
Yes, I thought it was too difficult to install an aperture linkage with MD 50/2 for G-Biogon 28mm,
so decided to make double-decker lens as you see. It does not look good, but it works fine.
p.6 #9 · lens repair, modification and disassembly guide thread
sebboh wrote:
one issue for me is that i don't presently have an m-mount adapter that hits infinity dead on with leica lenses so i can't tune infinity as well as i would like. hopefully at some point i'll be able to borrow a leica m so i can set the infinity stop precisely where it should be. does anyone know if the gxr flange distance is as consistant as leica's?
For what it's worth, here is my reference, calibrated Leica M to NEX adapter: http://farm4.staticflickr.com/3783/8750042343_b01d12d55d_z.jpg
The thickness looks to be .015" less than .400", or .385". The handle is 25 divisions per revolution. This is the true thickness sitting on the NEX camera. The photo shows the caliper flush against the NEX side, but this adapter has a .005" standoff lip that causes a .005" gap between the camera and adapter. So, my measurement is the true inside thickness.
When used with a Leica M camera and modern calibrated lenses, this Metabones was too thin and the lenses focused past infinity. I shimmed the adapter with I think it was .004".
p.6 #10 · lens repair, modification and disassembly guide thread
sebboh wrote:
harder actually, can't be done while the optics are installed. laziness won out.
Your laziness has more done on your project than my laziness has on my project.
p.6 #11 · lens repair, modification and disassembly guide thread
JimBuchanan wrote:
The thickness looks to be .015" less than .400", or .385". The handle is 25 divisions per revolution. This is the true thickness sitting on the NEX camera. The photo shows the caliper flush against the NEX side, but this adapter has a .005" standoff lip that causes a .005" gap between the camera and adapter. So, my measurement is the true inside thickness.
When used with a Leica M camera and modern calibrated lenses, this Metabones was too thin and the lenses focused past infinity. I shimmed the adapter with I think it was .004".
p.6 #12 · lens repair, modification and disassembly guide thread
Yes, .385". I only mention the standoff gap to give a heads up that some adapters may have a likewise gap. I didn't realize it at first, measuring the outer thickness. Then, on the camera I noticed the gap, and re-measured using the inner part of the adapter face that the camera mount contacts.
p.6 #14 · lens repair, modification and disassembly guide thread
Nice work! Contax G are wonderful lenses, but I wondered if there are any suggestions about adapting lenses from the small compact film cameras? I have seen contax T2 and T and yashica T lenses adapted so far. Has anyone tried to put Contax T3 lens on sony nex? Supposed to be better, but seems to be a more complicated construction (due to closer MFD I guess).
p.6 #15 · lens repair, modification and disassembly guide thread
Edgars Kalnins wrote:
Nice work! Contax G are wonderful lenses, but I wondered if there are any suggestions about adapting lenses from the small compact film cameras? I have seen contax T2 and T and yashica T lenses adapted so far. Has anyone tried to put Contax T3 lens on sony nex? Supposed to be better, but seems to be a more complicated construction (due to closer MFD I guess).
not sure, i've always been curious about those too but figured they probably wouldn't play well with NEX sensors.
p.6 #16 · lens repair, modification and disassembly guide thread
Beautiful work, D. The 28's prettier than the 45, so I'm assuming you don't really need the 45 back. You wouldn't want to give it an inferiority complex, would you?
p.6 #17 · lens repair, modification and disassembly guide thread
freaklikeme wrote:
Beautiful work, D. The 28's prettier than the 45, so I'm assuming you don't really need the 45 back. You wouldn't want to give it an inferiority complex, would you?
thanks! you like the silver better than the black too? maybe i should make another g45 conversion with the silver look. i took a shot out the window yesterday though and discovered the major weakness of the silver lens barrel.
i suspect my g28 feels a little out of place amongst all my rokkors though. he'd probably appreciate his big brother back at some point. have you used it much on the gxr?
p.6 #18 · lens repair, modification and disassembly guide thread
sebboh wrote:
thanks! you like the silver better than the black too? maybe i should make another g45 conversion with the silver look. i took a shot out the window yesterday though and discovered the major weakness of the silver lens barrel.
i suspect my g28 feels a little out of place amongst all my rokkors though. he'd probably appreciate his big brother back at some point. have you used it much on the gxr?
I figured it would have some practical issues, but it's very sleek looking. It does make you wonder why Zeiss likes to put the silver rings on the modern SLR lenses.
It's mounted on the GXR now. If the sky clears up today, I'll be using it for a pano this evening. I'm thinking I should send you the GXR when I send back the 45. I bet the 28 would give great results on it. It's a good time to do it, too, since I won't have any time for my oddball third camera again until the end of the summer.
p.6 #19 · lens repair, modification and disassembly guide thread
freaklikeme wrote:
I figured it would have some practical issues, but it's very sleek looking. It does make you wonder why Zeiss likes to put the silver rings on the modern SLR lenses.
It's mounted on the GXR now. If the sky clears up today, I'll be using it for a pano this evening. I'm thinking I should send you the GXR when I send back the 45. I bet the 28 would give great results on it. It's a good time to do it, too, since I won't have any time for my oddball third camera again until the end of the summer....Show more →
cool, that would probably solve my accurately tuning infinity for m-mount issue. i don't really have any rangefinder wides other than the g28, so i doubt the gxr would see much real world use for me. i am curious how the g45 and 40 cron compare on it to on the NEX-7 (have you tried your 35 lux on it?).
p.6 #20 · lens repair, modification and disassembly guide thread
I have been trying to adapt the Contax T2 Sonnar 38mm f2.8 on my sony nex-3. It has been done before, but it seems to me that the focusing abilities were limited or sacrificed for simplicity or other considerations. So far I have only attached the lens temporarily to check the quality of images. My skills being as they are I ended up removing the mount plate from my sony camera and selotaping the lens onto it! Close-ups look satisfying to me and I will update once I have some images at infinity.
Close-ups look satisfying to me and I will update once I have some images at infinity.
