Sigma k mount 600 mm

Damn_sam · 02-10-2022, 07:44 PM

Hi all hey just bought this lens the other day. All excited to try it out on the k-7. Disappointed, it will not fit, was told when I bought it, it’s sigma k mount. Is there an adapter to go from this lens to the K-7 or the K-70?

Attached Images

**UncleVanya** · 02-10-2022, 08:04 PM

I need to see the entire rear mount from directly above.

That black protrusion could possibly be running into the power zoom/sdm contacts or similar changed parts in the mount.

It’s also possible it isn’t Pentax. Nikon F looks quite similar.

**boriscleto** · 02-10-2022, 08:28 PM

The black protrusion is shifted too far past the bayonet flag. It isn’t needed as there is no aperture lever…

**UncleVanya** · 02-10-2022, 08:34 PM

Originally posted by boriscleto

The black protrusion is shifted too far past the bayonet flag. It isn’t needed as there is no aperture lever…

And yet… this image on the reviews section shows a similar protruding part on a supposedly Pentax fit Sigma 600 mirror lens. It isn’t the same color and perhaps not the same lens.

Sigma 600mm F8 Mirror Lens Reviews - Sigma Lenses - Pentax Lens Review Database

Damn_sam · 02-10-2022, 10:34 PM

Originally posted by UncleVanya

I need to see the entire rear mount from directly above.

That black protrusion could possibly be running into the power zoom/sdm contacts or similar changed parts in the mount.

It’s also possible it isn’t Pentax. Nikon F looks quite similar.

Hi here is a shot from top.

**boriscleto** · 02-11-2022, 05:52 AM

Originally posted by Damn_sam

Hi here is a shot from top.

it's a k-mount lens, Nikon would have the mount dot on the opposite side...

The 'aperture shield' should not be beyond the edge of the bayonet flag, the lens would mount to a K-mount that didn't have SDM contacts with no problems.

Damn_sam · 02-11-2022, 06:21 AM

Is there an adapter or Remedy for this to work?

**UncleVanya** · 02-11-2022, 06:46 AM

Originally posted by Damn_sam

Is there an adapter or Remedy for this to work?

I think if you remove the three screws that part will come out. Then with a cutting tool you can remove the protruding part and it probably will fit. The part was probably used on multiple lenses and was designed to protect the aperture lever used in another lens. Since this lens has a fixed aperture, removal has no negatives.

---------- Post added 02-11-22 at 08:49 AM ----------

You do want to be careful not to allow the dust created a or metal fragments from contaminating your gear, so cut it in a place where you can clean up the debris and it won’t get into the air if you use a tool that might produce fine airborne debris. A simple cutting wheel job done outside is probably good. A manual removal using a smaller hacksaw also might work. You may want to use flat black paint to mask any shiny scars left after removal.

---------- Post added 02-11-22 at 08:50 AM ----------

And be sure to avoid bending the mount!

**marcusBMG** · 02-11-2022, 07:21 AM

That aperture lever guard is completely superfluous on this lens - there is no iris and no lever! Its probably plastic - just cut it off (IIRC the sigma 400mm and sigma 600mm I had didn't have this issue).
Mirror lenses are interesting to play with but I found the sigma 600mm of merely ok iq and little utility. I take out the tamron 500mm more often because I have the 02F eyepiece to go with it - makes a good compact 25x spotting scope.

**mlag** · 02-11-2022, 02:05 PM

1) Strangely enough my mount of the same (sigma 600mm - the first top lens images are identical) lens looks quite different (and similar at the same time...). yours seems to have a protection / hole to accept an aperture sensor or so, mine not.
your serial starts with 2 , mine with 1 so probably different production run.

2) There are some dirt/friction traces on your mount at the bottom of above "top view" picture, showing increased friction/wear on the mount (on one of 3 flanges) and on one of the three screws : is it possible this screw is protruding a bit ? It looks like a bad mounted screw (tilted a bit?) This might block a bit the full rotation of mount...?2.12.0.0

Damn_sam · 02-11-2022, 02:07 PM

Yes I have another sigma 600mm OM mount. It’s on a Om to Fuji adapter. I got this one for the k-50 or 70 so I could keep the small form factor!

---------- Post added 02-11-22 at 02:10 PM ----------

Originally posted by UncleVanya

I think if you remove the three screws that part will come out. Then with a cutting tool you can remove the protruding part and it probably will fit. The part was probably used on multiple lenses and was designed to protect the aperture lever used in another lens. Since this lens has a fixed aperture, removal has no negatives.

---------- Post added 02-11-22 at 08:49 AM ----------

You do want to be careful not to allow the dust created a or metal fragments from contaminating your gear, so cut it in a place where you can clean up the debris and it won’t get into the air if you use a tool that might produce fine airborne debris. A simple cutting wheel job done outside is probably good. A manual removal using a smaller hacksaw also might work. You may want to use flat black paint to mask any shiny scars left after removal.

---------- Post added 02-11-22 at 08:50 AM ----------

And be sure to avoid bending the mount!

Thanks looks like a project for tonight!

---------- Post added 02-11-22 at 02:16 PM ----------

Originally posted by mlag

1) Strangely enough my mount of the same (sigma 600mm - the first top lens images are identical) lens looks quite different (and similar at the same time...). yours seems to have a protection / hole to accept an aperture sensor or so, mine not.
your serial starts with 2 , mine with 1 so probably different production run.

2) There are some dirt/friction traces on your mount at the bottom of above "top view" picture, showing increased friction/wear on the mount (on one of 3 flanges) and on one of the three screws : is it possible this screw is protruding a bit ? It looks like a bad mounted screw (tilted a bit?) This might block a bit the full rotation of mount...?2.12.0.0

I will at it when home. That would be nice if it just needed tightened!

pimpim · 02-11-2022, 03:08 PM

could this be a sigma SA mount? they are very similar, use the same rear caps for example.

**Kerrowdown** · 02-12-2022, 02:38 AM

Welcome aboard, hope you get your issues resolved promptly

Damn_sam · 02-12-2022, 08:13 PM

Originally posted by UncleVanya

I think if you remove the three screws that part will come out. Then with a cutting tool you can remove the protruding part and it probably will fit. The part was probably used on multiple lenses and was designed to protect the aperture lever used in another lens. Since this lens has a fixed aperture, removal has no negatives.

---------- Post added 02-11-22 at 08:49 AM ----------

You do want to be careful not to allow the dust created a or metal fragments from contaminating your gear, so cut it in a place where you can clean up the debris and it won’t get into the air if you use a tool that might produce fine airborne debris. A simple cutting wheel job done outside is probably good. A manual removal using a smaller hacksaw also might work. You may want to use flat black paint to mask any shiny scars left after removal.

---------- Post added 02-11-22 at 08:50 AM ----------

And be sure to avoid bending the mount!

Hi well I had the black inside flange off. The plastic was very brittle! Very brittle! The bayonet broke off. I but the ring back on! And seems to fit and work! But no bayonet needed?

**UncleVanya** · 02-13-2022, 05:17 AM

Originally posted by Damn_sam

Hi well I had the black inside flange off. The plastic was very brittle! Very brittle! The bayonet broke off. I but the ring back on! And seems to fit and work! But no bayonet needed?

I’m not sure I follow. Post an image perhaps? If you are saying one of the three bayonet lugs broke off I think that’s a problem. But those look to be metal not plastic, so I’m confused.

02-10-2022, 07:44 PM	#1
Damn_sam New Member Join Date: Feb 2022 Posts: 10	Sigma k mount 600 mm Hi all hey just bought this lens the other day. All excited to try it out on the k-7. Disappointed, it will not fit, was told when I bought it, it’s sigma k mount. Is there an adapter to go from this lens to the K-7 or the K-70? Attached Images

02-10-2022, 10:34 PM	#5
Damn_sam New Member Join Date: Feb 2022 Posts: 10 Original Poster	Originally posted by UncleVanya I need to see the entire rear mount from directly above. That black protrusion could possibly be running into the power zoom/sdm contacts or similar changed parts in the mount. It’s also possible it isn’t Pentax. Nikon F looks quite similar. Hi here is a shot from top. Attached Images

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Where to get accessories for the FA* 300/2.8, FA* 600/4, FA* 250-600, A* 400/2.8, etc	Clinton	Pentax SLR Lens Discussion	28	07-13-2023 12:07 AM
Nature Isle aux Coudres @ 28 mm, 45 mm and 63 mm FL with DFA 28-105 mm HD and f/16.	RICHARD L.	Post Your Photos!	6	02-25-2022 05:25 AM
For Sale - Sold: Brand New FA 31 mm, FA 77 mm, DA* 60-250 mm, DA* 300 mm	ppkkcao	Sold Items	14	11-02-2014 08:42 PM

02-10-2022, 08:04 PM	#2
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,407	I need to see the entire rear mount from directly above. That black protrusion could possibly be running into the power zoom/sdm contacts or similar changed parts in the mount. It’s also possible it isn’t Pentax. Nikon F looks quite similar.

02-10-2022, 08:28 PM	#3
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	The black protrusion is shifted too far past the bayonet flag. It isn’t needed as there is no aperture lever…

02-10-2022, 08:34 PM	#4
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,407	Originally posted by boriscleto The black protrusion is shifted too far past the bayonet flag. It isn’t needed as there is no aperture lever… And yet… this image on the reviews section shows a similar protruding part on a supposedly Pentax fit Sigma 600 mirror lens. It isn’t the same color and perhaps not the same lens. Sigma 600mm F8 Mirror Lens Reviews - Sigma Lenses - Pentax Lens Review Database

02-11-2022, 05:52 AM	#6
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	Originally posted by Damn_sam Hi here is a shot from top. it's a k-mount lens, Nikon would have the mount dot on the opposite side... The 'aperture shield' should not be beyond the edge of the bayonet flag, the lens would mount to a K-mount that didn't have SDM contacts with no problems.

02-11-2022, 06:21 AM	#7
Damn_sam New Member Join Date: Feb 2022 Posts: 10 Original Poster	Is there an adapter or Remedy for this to work?

02-11-2022, 06:46 AM	#8
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,407	Originally posted by Damn_sam Is there an adapter or Remedy for this to work? I think if you remove the three screws that part will come out. Then with a cutting tool you can remove the protruding part and it probably will fit. The part was probably used on multiple lenses and was designed to protect the aperture lever used in another lens. Since this lens has a fixed aperture, removal has no negatives. ---------- Post added 02-11-22 at 08:49 AM ---------- You do want to be careful not to allow the dust created a or metal fragments from contaminating your gear, so cut it in a place where you can clean up the debris and it won’t get into the air if you use a tool that might produce fine airborne debris. A simple cutting wheel job done outside is probably good. A manual removal using a smaller hacksaw also might work. You may want to use flat black paint to mask any shiny scars left after removal. ---------- Post added 02-11-22 at 08:50 AM ---------- And be sure to avoid bending the mount!

02-11-2022, 07:21 AM	#9
marcusBMG Site Supporter Join Date: Nov 2012 Location: North Wales Photos: Gallery \| Albums Posts: 2,869	That aperture lever guard is completely superfluous on this lens - there is no iris and no lever! Its probably plastic - just cut it off (IIRC the sigma 400mm and sigma 600mm I had didn't have this issue). Mirror lenses are interesting to play with but I found the sigma 600mm of merely ok iq and little utility. I take out the tamron 500mm more often because I have the 02F eyepiece to go with it - makes a good compact 25x spotting scope.

02-11-2022, 02:07 PM	#11
Damn_sam New Member Join Date: Feb 2022 Posts: 10 Original Poster	Yes I have another sigma 600mm OM mount. It’s on a Om to Fuji adapter. I got this one for the k-50 or 70 so I could keep the small form factor! ---------- Post added 02-11-22 at 02:10 PM ---------- Originally posted by UncleVanya I think if you remove the three screws that part will come out. Then with a cutting tool you can remove the protruding part and it probably will fit. The part was probably used on multiple lenses and was designed to protect the aperture lever used in another lens. Since this lens has a fixed aperture, removal has no negatives. ---------- Post added 02-11-22 at 08:49 AM ---------- You do want to be careful not to allow the dust created a or metal fragments from contaminating your gear, so cut it in a place where you can clean up the debris and it won’t get into the air if you use a tool that might produce fine airborne debris. A simple cutting wheel job done outside is probably good. A manual removal using a smaller hacksaw also might work. You may want to use flat black paint to mask any shiny scars left after removal. ---------- Post added 02-11-22 at 08:50 AM ---------- And be sure to avoid bending the mount! Thanks looks like a project for tonight! ---------- Post added 02-11-22 at 02:16 PM ---------- Originally posted by mlag 1) Strangely enough my mount of the same (sigma 600mm - the first top lens images are identical) lens looks quite different (and similar at the same time...). yours seems to have a protection / hole to accept an aperture sensor or so, mine not. your serial starts with 2 , mine with 1 so probably different production run. 2) There are some dirt/friction traces on your mount at the bottom of above "top view" picture, showing increased friction/wear on the mount (on one of 3 flanges) and on one of the three screws : is it possible this screw is protruding a bit ? It looks like a bad mounted screw (tilted a bit?) This might block a bit the full rotation of mount...?2.12.0.0 I will at it when home. That would be nice if it just needed tightened!

02-11-2022, 03:08 PM	#12
pimpim Senior Member Join Date: Sep 2010 Location: Mainz Photos: Albums Posts: 253	could this be a sigma SA mount? they are very similar, use the same rear caps for example.

02-12-2022, 02:38 AM	#13
Kerrowdown PEG Moderator Join Date: Aug 2008 Location: Highlands of Scotland... "Hold Infinity in the palm of your hand" - William Blake Photos: Gallery Posts: 57,819	Welcome aboard, hope you get your issues resolved promptly

02-12-2022, 08:13 PM	#14
Damn_sam New Member Join Date: Feb 2022 Posts: 10 Original Poster	Originally posted by UncleVanya I think if you remove the three screws that part will come out. Then with a cutting tool you can remove the protruding part and it probably will fit. The part was probably used on multiple lenses and was designed to protect the aperture lever used in another lens. Since this lens has a fixed aperture, removal has no negatives. ---------- Post added 02-11-22 at 08:49 AM ---------- You do want to be careful not to allow the dust created a or metal fragments from contaminating your gear, so cut it in a place where you can clean up the debris and it won’t get into the air if you use a tool that might produce fine airborne debris. A simple cutting wheel job done outside is probably good. A manual removal using a smaller hacksaw also might work. You may want to use flat black paint to mask any shiny scars left after removal. ---------- Post added 02-11-22 at 08:50 AM ---------- And be sure to avoid bending the mount! Hi well I had the black inside flange off. The plastic was very brittle! Very brittle! The bayonet broke off. I but the ring back on! And seems to fit and work! But no bayonet needed?

02-13-2022, 05:17 AM	#15
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,407	Originally posted by Damn_sam Hi well I had the black inside flange off. The plastic was very brittle! Very brittle! The bayonet broke off. I but the ring back on! And seems to fit and work! But no bayonet needed? I’m not sure I follow. Post an image perhaps? If you are saying one of the three bayonet lugs broke off I think that’s a problem. But those look to be metal not plastic, so I’m confused.