Flexar 400mm f6.3

Lurch · 02-26-2013, 04:05 PM

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Morning all,

I recently picked up an old Flexar 400mm 6.3. I'm assuming its just a generic lens of some description?

Anyway; the mount point is this:

It seems removable with the three little screws; but is this some kind of generic mount piece? Can I get a K-mount version to replace it?

Cheers,
Lurch

**boriscleto** · 02-26-2013, 04:13 PM

T-mount - Wikipedia, the free encyclopedia

You will need a T-ring adapter to attach it to the camera. For example...

General Brand T-Mount SLR Camera Adapter for Pentax K ATPK B&H

You should be able to get one cheaper locally.

Lurch · 02-26-2013, 04:15 PM

*Ding* - thanks mate.
I thought that was the case, but I got confused between a t-mount and an adaptall?

**boriscleto** · 02-26-2013, 04:19 PM

Originally posted by Lurch

*Ding* - thanks mate.
I thought that was the case, but I got confused between a t-mount and an adaptall?

Adaptall is a later mount that allowed for automated aperture.

Matt's Classic Cameras: Tamron Adaptall-2 System

The other systems were Soligor's T4 mount which evolved into the Vivitar TX mount. Sigma had the YS mount.

Lurch · 02-26-2013, 04:22 PM

Ahh - gotchya.

BTW; is there any real benefit to replacing the T-Mount as opposed to just using a M42/K adapter on teh existing T-Mount?

vonBaloney · 02-26-2013, 04:29 PM

Originally posted by Lurch

Ahh - gotchya.

BTW; is there any real benefit to replacing the T-Mount as opposed to just using a M42/K adapter on teh existing T-Mount?

No, just get an adapter. That's what you're supposed to do -- there is no such thing as "t-mount camera".

They're cheap. This one is good:

T2 T Mount T Ring Adapter for Pentax K PK K 7 K x K20D | eBay

The thing that is removable probably *is* an adapter -- m42 I suspect. Underneath it are the t-mount screws (which are also 42mm, but different pitch).

Lurch · 02-26-2013, 04:34 PM

Ahh - ok; let me re-phrase that..
I figure I can either:
Get a whole new T-Mount > PK Adapter or
Just get a M42>PK adapter to screw onto the existing T-Mount > M42 adapter.

**boriscleto** · 02-26-2013, 05:00 PM

Originally posted by Lurch

Ahh - ok; let me re-phrase that..
I figure I can either:
Get a whole new T-Mount > PK Adapter or
Just get a M42>PK adapter to screw onto the existing T-Mount > M42 adapter.

There are 2 parts to the T-mount. The first is the T-mount adapter that is already on the lens. That is a 42mm x .75 mm thread pitch. (M42 is 42mm x 1mm). The second part is the T-ring adapter. That is the part that mounts the lens to the camera. What you need is the T->PK ring.

vonBaloney · 02-26-2013, 05:05 PM

Originally posted by Lurch

Ahh - ok; let me re-phrase that..
I figure I can either:
Get a whole new T-Mount > PK Adapter or
Just get a M42>PK adapter to screw onto the existing T-Mount > M42 adapter.

One adapter or another, yes. Don't spend too much -- that lens probably isn't worth it. There are a million of those generic t-mount 400/6.3s out there and most of them are relatively crappy. Expect heavy lateral CA on the edges -- this is a lens that actually becomes sharper in post-processing if you have Lightroom 4 or similar because it will rescale the misaligned colors. You can get a decent image of it (at least in the center) if you stop down to f11 and use a tripod.

excanonfd · 02-26-2013, 05:11 PM

As Boriscleto says, the thread pitch is different, You will be able to screw the M42 adapter on the T2 mount about 1 turn before it stops, if you try forcing them together, you'll ruin one or both parts, rendering your lens useless. Safest to get a T-K ring.

Lurch · 02-26-2013, 05:29 PM

Hmm...
This lense only seems to have one 'bit'

And the screw size is definitely M42

vonBaloney · 02-26-2013, 05:36 PM

I think you've left part of the adapter on -- t-mount adapters are often built like that with an inner ring that comes out. You should be able to unscrew the remaining ring...

Lurch · 02-26-2013, 05:46 PM

Ah-HAH!!

Thanks guys!

vonBaloney · 02-26-2013, 05:54 PM

Yeah, so you could have just unscrewed it I guess (sometimes they are locked down though). So that ring goes back in the adapter -- not sure why they make them like that...

Lurch · 02-26-2013, 05:56 PM

So its the bit on the far right I want to replace with a K version?
I cant help but think that with this lens meaning to sit on a tripod, just putting a simply M42>K adapter would have the strength.

02-26-2013, 04:05 PM	#1
Lurch Veteran Member Join Date: Apr 2011 Location: Canberra, Australia Photos: Gallery \| Albums Posts: 582	Flexar 400mm f6.3 Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here. Morning all, I recently picked up an old Flexar 400mm 6.3. I'm assuming its just a generic lens of some description? Anyway; the mount point is this: It seems removable with the three little screws; but is this some kind of generic mount piece? Can I get a K-mount version to replace it? Cheers, Lurch

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02-26-2013, 04:13 PM	#2
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	T-mount - Wikipedia, the free encyclopedia You will need a T-ring adapter to attach it to the camera. For example... General Brand T-Mount SLR Camera Adapter for Pentax K ATPK B&H You should be able to get one cheaper locally.

02-26-2013, 04:15 PM	#3
Lurch Veteran Member Join Date: Apr 2011 Location: Canberra, Australia Photos: Gallery \| Albums Posts: 582 Original Poster	Ding - thanks mate. I thought that was the case, but I got confused between a t-mount and an adaptall?

02-26-2013, 04:19 PM	#4
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	Originally posted by Lurch Ding - thanks mate. I thought that was the case, but I got confused between a t-mount and an adaptall? Adaptall is a later mount that allowed for automated aperture. Matt's Classic Cameras: Tamron Adaptall-2 System The other systems were Soligor's T4 mount which evolved into the Vivitar TX mount. Sigma had the YS mount.

02-26-2013, 04:22 PM	#5
Lurch Veteran Member Join Date: Apr 2011 Location: Canberra, Australia Photos: Gallery \| Albums Posts: 582 Original Poster	Ahh - gotchya. BTW; is there any real benefit to replacing the T-Mount as opposed to just using a M42/K adapter on teh existing T-Mount?

02-26-2013, 04:29 PM	#6
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by Lurch Ahh - gotchya. BTW; is there any real benefit to replacing the T-Mount as opposed to just using a M42/K adapter on teh existing T-Mount? No, just get an adapter. That's what you're supposed to do -- there is no such thing as "t-mount camera". They're cheap. This one is good: T2 T Mount T Ring Adapter for Pentax K PK K 7 K x K20D \| eBay The thing that is removable probably is an adapter -- m42 I suspect. Underneath it are the t-mount screws (which are also 42mm, but different pitch).

02-26-2013, 04:34 PM	#7
Lurch Veteran Member Join Date: Apr 2011 Location: Canberra, Australia Photos: Gallery \| Albums Posts: 582 Original Poster	Ahh - ok; let me re-phrase that.. I figure I can either: Get a whole new T-Mount > PK Adapter or Just get a M42>PK adapter to screw onto the existing T-Mount > M42 adapter.

02-26-2013, 05:00 PM	#8
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	Originally posted by Lurch Ahh - ok; let me re-phrase that.. I figure I can either: Get a whole new T-Mount > PK Adapter or Just get a M42>PK adapter to screw onto the existing T-Mount > M42 adapter. There are 2 parts to the T-mount. The first is the T-mount adapter that is already on the lens. That is a 42mm x .75 mm thread pitch. (M42 is 42mm x 1mm). The second part is the T-ring adapter. That is the part that mounts the lens to the camera. What you need is the T->PK ring.

02-26-2013, 05:05 PM	#9
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by Lurch Ahh - ok; let me re-phrase that.. I figure I can either: Get a whole new T-Mount > PK Adapter or Just get a M42>PK adapter to screw onto the existing T-Mount > M42 adapter. One adapter or another, yes. Don't spend too much -- that lens probably isn't worth it. There are a million of those generic t-mount 400/6.3s out there and most of them are relatively crappy. Expect heavy lateral CA on the edges -- this is a lens that actually becomes sharper in post-processing if you have Lightroom 4 or similar because it will rescale the misaligned colors. You can get a decent image of it (at least in the center) if you stop down to f11 and use a tripod.

02-26-2013, 05:11 PM	#10
excanonfd Veteran Member Join Date: Jan 2010 Location: Vancouver, BC Posts: 1,421	As Boriscleto says, the thread pitch is different, You will be able to screw the M42 adapter on the T2 mount about 1 turn before it stops, if you try forcing them together, you'll ruin one or both parts, rendering your lens useless. Safest to get a T-K ring.

02-26-2013, 05:29 PM	#11
Lurch Veteran Member Join Date: Apr 2011 Location: Canberra, Australia Photos: Gallery \| Albums Posts: 582 Original Poster	Hmm... This lense only seems to have one 'bit' And the screw size is definitely M42

02-26-2013, 05:36 PM	#12
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	I think you've left part of the adapter on -- t-mount adapters are often built like that with an inner ring that comes out. You should be able to unscrew the remaining ring...

02-26-2013, 05:46 PM	#13
Lurch Veteran Member Join Date: Apr 2011 Location: Canberra, Australia Photos: Gallery \| Albums Posts: 582 Original Poster	Ah-HAH!! Thanks guys!

02-26-2013, 05:54 PM	#14
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Yeah, so you could have just unscrewed it I guess (sometimes they are locked down though). So that ring goes back in the adapter -- not sure why they make them like that...

02-26-2013, 05:56 PM	#15
Lurch Veteran Member Join Date: Apr 2011 Location: Canberra, Australia Photos: Gallery \| Albums Posts: 582 Original Poster	So its the bit on the far right I want to replace with a K version? I cant help but think that with this lens meaning to sit on a tripod, just putting a simply M42>K adapter would have the strength.