Nikkor 105mm f2.5 non-AI on K10D

Nachodog · 04-24-2009, 01:59 PM

Upon reading another thread found here, I purchased a Nikkor 105mm at a camera show. I got a good deal for it because a previous owner had tried to modify it, but only got part of the job done.

Here are some photos of the lens in question (These photos are post-modification):

The first thing I did was use an orbital sander to make the aperture ring narrower. This will give the mount a bit more clearance.

In order to do this, i had to remove the aperture ring altogether. This was easy to do once I removed the retention screw and the aperture ring just screws off.

The retention screw also moves the aperture blades open and closed by moving a slot back and forth. When putting the aperture ring back, it's important to keep this in mind and make sure the retention screw is lined up with the slot.

Once that was done, I drilled a whole in the mount collar to get the lens to lock on to the lock pin on the camera. You'll notice that I drilled two holes. The one on the bottom was an earlier miscalculated hole.

It's not pretty, but I'm perfectly confident that I won't drop it by accident. One thing to keep in mind is that a drilled hole will be tapered if it is shallow and the lock pin will simply slip out. I had to grind the hole so the side that the lock pin grabs onto was perpendicular instead of sloped.

Let me know if you're interested in sample pictures, I'll try to take some and post them.

**pacerr** · 04-24-2009, 07:03 PM

>" One thing to keep in mind is that a drilled hole will be tapered if it is shallow and the lock pin will simply slip out.

You can easily square-up/clean up the hole (or do the whole job) with one of the carbide/diamond burrs or milling bits made for the Dremel or other rotary tools.

I intentionally off-set the notch about 20 degrees when possible (depending on how the lens seats on the mount) so the flash bulge doesn't hide the aperture ring.

H2

ilya80 · 04-25-2009, 01:14 AM

Please post the samples, wide open included please.

Nachodog · 04-29-2009, 02:02 PM

Here are some samples (no pp only resized):

f2.5 - iso 100 - 1/1000 s

100% crop @2.5 (weird bokeh wide open)

100% crop @2.5

f5.6 - iso 100 - 1/250 s

100% crop @5.6

f8 - iso 100 - 1/125 s

Overall, I'm very happy with this lens. It's quite sharp when I can manage to focus it. I'm thinking a new split prism focus screen might be in order.

davef · 04-29-2009, 03:52 PM

This was my favourite protrait lens way back when I used a Nikon F and other Nikon film bodies.... Dave

Wheatfield · 04-29-2009, 04:57 PM

I don't suppose you'd part with the rabbit ears and retaining screws would you?

Nachodog · 04-29-2009, 05:22 PM

Originally posted by Wheatfield

I don't suppose you'd part with the rabbit ears and retaining screws would you?

Wouldn't bother me a bit. Although, since I took the orbital sander to the aperture ring, i actually sliced about 1/3 of the screw head off. Not sure it'd be any use to you in that state.

If I get my hands on another Nikkor, I'll take them off before I sand it down and they're yours.

roentarre · 04-29-2009, 10:23 PM

Depends on the pricing, it is not bad as a lens. I found the harsh edged bokeh a little concerning there.

The colour is usually not a problem with old Nikon primes. There is little flat look to their images as well.

Nachodog · 04-30-2009, 07:17 AM

Originally posted by roentarre

Depends on the pricing, it is not bad as a lens. I found the harsh edged bokeh a little concerning there.

The colour is usually not a problem with old Nikon primes. There is little flat look to their images as well.

Hmmm... you've got me a bit worried. I noticed that my shots all feel a bit flat, but I chalked it up to my dingy screen. I've noticed this with a few of my other lenses as well. Could there be something wrong with my camera? Any ideas?

I think I'll investigate further when I get home.

Wheatfield · 04-30-2009, 08:53 AM

Originally posted by Nachodog

Wouldn't bother me a bit. Although, since I took the orbital sander to the aperture ring, i actually sliced about 1/3 of the screw head off. Not sure it'd be any use to you in that state.

If I get my hands on another Nikkor, I'll take them off before I sand it down and they're yours.

PM sent.
As part of my middle aged craziness I decided that I wanted to build the Nikon kit that I dreamed of when I was a teenager.
With this in mind I sent out shopping on ebay and found some very well kept equipment from the mid 1970s (F2s and a few lenses that were it's contemporaries), but one of the lenses that I bought was missing the rabbit ears.
I'll grab this from you, I probably have a screw or two around the house that will work.

Thanks

Nachodog · 05-09-2009, 07:24 PM

Here is another shot with the Nikkor. I think I figured out the colour issue (wrong colourspace) and the focus is spot on. I'm very impressed with this lens and what it can do. It seems that I'm the weakest link here, not the lens.

Taken @ f8 and resized:

100% crop:

mikeSF · 05-09-2009, 10:34 PM

Originally posted by Nachodog

Here is another shot with the Nikkor. I think I figured out the colour issue (wrong colourspace) and the focus is spot on. I'm very impressed with this lens and what it can do. It seems that I'm the weakest link here, not the lens.

Taken @ f8 and resized:

Channel 6 is the cowbell track...please turn it UP!

04-24-2009, 01:59 PM	#1
Nachodog Veteran Member Join Date: Dec 2007 Location: Montreal, Qc Posts: 472	Nikkor 105mm f2.5 non-AI on K10D Upon reading another thread found here, I purchased a Nikkor 105mm at a camera show. I got a good deal for it because a previous owner had tried to modify it, but only got part of the job done. Here are some photos of the lens in question (These photos are post-modification): The first thing I did was use an orbital sander to make the aperture ring narrower. This will give the mount a bit more clearance. In order to do this, i had to remove the aperture ring altogether. This was easy to do once I removed the retention screw and the aperture ring just screws off. The retention screw also moves the aperture blades open and closed by moving a slot back and forth. When putting the aperture ring back, it's important to keep this in mind and make sure the retention screw is lined up with the slot. Once that was done, I drilled a whole in the mount collar to get the lens to lock on to the lock pin on the camera. You'll notice that I drilled two holes. The one on the bottom was an earlier miscalculated hole. It's not pretty, but I'm perfectly confident that I won't drop it by accident. One thing to keep in mind is that a drilled hole will be tapered if it is shallow and the lock pin will simply slip out. I had to grind the hole so the side that the lock pin grabs onto was perpendicular instead of sloped. Let me know if you're interested in sample pictures, I'll try to take some and post them.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
For Sale - Sold: Nikkor Ai 105mm f/2.5, adapted to Pentax K-mount (US/CAN)	farfisa	Sold Items	3	05-06-2010 01:45 PM
For Sale - Sold: Nikon Nikkor 105mm f/2.5	Voe	Sold Items	3	08-19-2009 01:41 PM
Modify Micro-Nikkor 55mm for use with K10d	Nachodog	Pentax SLR Lens Discussion	1	07-15-2009 05:39 PM
K10D and Vivitar 105mm PK-A/R mount?	Tom M	Pentax DSLR Discussion	15	09-19-2007 08:58 AM

04-24-2009, 07:03 PM	#2
pacerr Loyal Site Supporter Join Date: Jan 2008 Location: Paris, TN Photos: Gallery \| Albums Posts: 3,350	>" One thing to keep in mind is that a drilled hole will be tapered if it is shallow and the lock pin will simply slip out. You can easily square-up/clean up the hole (or do the whole job) with one of the carbide/diamond burrs or milling bits made for the Dremel or other rotary tools. I intentionally off-set the notch about 20 degrees when possible (depending on how the lens seats on the mount) so the flash bulge doesn't hide the aperture ring. H2

04-25-2009, 01:14 AM	#3
ilya80 Veteran Member Join Date: Oct 2008 Location: Saint-Petersburg, Russia Photos: Albums Posts: 410	Please post the samples, wide open included please.

04-29-2009, 02:02 PM	#4
Nachodog Veteran Member Join Date: Dec 2007 Location: Montreal, Qc Posts: 472 Original Poster	Here are some samples (no pp only resized): f2.5 - iso 100 - 1/1000 s 100% crop @2.5 (weird bokeh wide open) 100% crop @2.5 f5.6 - iso 100 - 1/250 s 100% crop @5.6 f8 - iso 100 - 1/125 s Overall, I'm very happy with this lens. It's quite sharp when I can manage to focus it. I'm thinking a new split prism focus screen might be in order.

04-29-2009, 03:52 PM	#5
davef Veteran Member Join Date: Feb 2007 Location: Ontario Posts: 433	This was my favourite protrait lens way back when I used a Nikon F and other Nikon film bodies.... Dave

04-29-2009, 04:57 PM	#6
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,986	I don't suppose you'd part with the rabbit ears and retaining screws would you?

04-29-2009, 05:22 PM	#7
Nachodog Veteran Member Join Date: Dec 2007 Location: Montreal, Qc Posts: 472 Original Poster	Originally posted by Wheatfield I don't suppose you'd part with the rabbit ears and retaining screws would you? Wouldn't bother me a bit. Although, since I took the orbital sander to the aperture ring, i actually sliced about 1/3 of the screw head off. Not sure it'd be any use to you in that state. If I get my hands on another Nikkor, I'll take them off before I sand it down and they're yours.

04-29-2009, 10:23 PM	#8
roentarre Veteran Member Join Date: Oct 2006 Location: Melbourne, Australia Posts: 11,783	Depends on the pricing, it is not bad as a lens. I found the harsh edged bokeh a little concerning there. The colour is usually not a problem with old Nikon primes. There is little flat look to their images as well.

04-30-2009, 07:17 AM	#9
Nachodog Veteran Member Join Date: Dec 2007 Location: Montreal, Qc Posts: 472 Original Poster	Originally posted by roentarre Depends on the pricing, it is not bad as a lens. I found the harsh edged bokeh a little concerning there. The colour is usually not a problem with old Nikon primes. There is little flat look to their images as well. Hmmm... you've got me a bit worried. I noticed that my shots all feel a bit flat, but I chalked it up to my dingy screen. I've noticed this with a few of my other lenses as well. Could there be something wrong with my camera? Any ideas? I think I'll investigate further when I get home.

04-30-2009, 08:53 AM	#10
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,986	Originally posted by Nachodog Wouldn't bother me a bit. Although, since I took the orbital sander to the aperture ring, i actually sliced about 1/3 of the screw head off. Not sure it'd be any use to you in that state. If I get my hands on another Nikkor, I'll take them off before I sand it down and they're yours. PM sent. As part of my middle aged craziness I decided that I wanted to build the Nikon kit that I dreamed of when I was a teenager. With this in mind I sent out shopping on ebay and found some very well kept equipment from the mid 1970s (F2s and a few lenses that were it's contemporaries), but one of the lenses that I bought was missing the rabbit ears. I'll grab this from you, I probably have a screw or two around the house that will work. Thanks

05-09-2009, 07:24 PM	#11
Nachodog Veteran Member Join Date: Dec 2007 Location: Montreal, Qc Posts: 472 Original Poster	Here is another shot with the Nikkor. I think I figured out the colour issue (wrong colourspace) and the focus is spot on. I'm very impressed with this lens and what it can do. It seems that I'm the weakest link here, not the lens. Taken @ f8 and resized: 100% crop:

05-09-2009, 10:34 PM	#12
mikeSF Pentaxian Join Date: Jan 2009 Location: East Bay Area, CA Photos: Gallery Posts: 6,622	Originally posted by Nachodog Here is another shot with the Nikkor. I think I figured out the colour issue (wrong colourspace) and the focus is spot on. I'm very impressed with this lens and what it can do. It seems that I'm the weakest link here, not the lens. Taken @ f8 and resized: Channel 6 is the cowbell track...please turn it UP!