Pentax Film SLR prism compatability

dmjohn1337 · 09-02-2018, 01:17 PM

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.

Hi all,

First time poster, but I have visited this forum many times and have found them to be very helpful! So I have a Pentax K2 that has a desilvered prism. My question is how likely is it that a prism out of another K body (or even a Spotmatic) would work in the K2. Thanks!

**boriscleto** · 09-02-2018, 02:58 PM

I'm pretty sure the K2 used the same prism as the rest of the K series, and the Spotmatic. There was a thread a while back in which the original poster was buying up Spotmatics to cannibalize the prism to refit K1000s for resale.

**gofour3** · 09-02-2018, 04:10 PM

Originally posted by dmjohn1337

Hi all,

First time poster, but I have visited this forum many times and have found them to be very helpful! So I have a Pentax K2 that has a desilvered prism. My question is how likely is it that a prism out of another K body (or even a Spotmatic) would work in the K2. Thanks!

Best check with Eric, he will know. Not sure about prisms, but he told me once that the focusing screens in a K2 are a different size than a KX/KM/K1000.

Phil.

**pentaxus** · 09-02-2018, 11:26 PM

The focusing screen and prism are a little wider in the K2.

Wild Mark · 09-03-2018, 04:02 AM

The K2 prism is different to the KX, KM and K1000. I think it is even different to its M42 mount sister - the ESII

I have some dead K2 prisms and have compared them to the one linked below as listed on ebay (I am not linked to the seller)

Asahi Pentax SLR Sucher Prisma / new finder prism - old stock (NEU) | eBay

It looks like the real deal. Perhaps worth the punt?

Lord Lucan · 09-10-2018, 01:28 AM

Originally posted by boriscleto

There was a thread a while back in which the original poster was buying up Spotmatics to cannibalize the prism to refit K1000s for resale.

The K1000 (and the KM) was a Spotmatic F with a bayonet mount, and otherwise only detailed differences, so that is a no-brainer. It would not necessarily apply to the K2 or KX though.

stevebrot · 09-10-2018, 01:51 PM

Originally posted by boriscleto

I'm pretty sure the K2 used the same prism as the rest of the K series, and the Spotmatic. There was a thread a while back in which the original poster was buying up Spotmatics to cannibalize the prism to refit K1000s for resale.

One would think, except that the focus screen is larger than other K-series bodies. implying differences in the prism and/or ocular.

Steve

**boriscleto** · 09-10-2018, 02:38 PM

Originally posted by stevebrot

One would think, except that the focus screen is larger than other K-series bodies. implying differences in the prism and/or ocular.

Steve

I've never even seen a K2, let alone looked through the viewfinder of one, so I guess I should have looked it up

The KX, KM, & K1000 are all the same body though...the KX has different meter...

stevebrot · 09-10-2018, 02:44 PM

Originally posted by boriscleto

I've never even seen a K2, let alone looked through the viewfinder of one, so I guess I should have looked it up

I have handled one, but my comment was based on a recent camera comparison post from @LesDMess. The image below was rather enlightening...

Steve

stevebrot · 09-10-2018, 02:48 PM

Originally posted by boriscleto

The KX, KM, & K1000 are all the same body though...the KX has different meter...

~~The KX is different size-wise too, though just a millimeter or so here and there.~~

Nope...wrong. It is officially identical dimensions, according to the user manuals. However, this site has different measurements between the K2, KM, KX, and K1000. The K1000 is the same as the Spotmatic F except for being a little shorter.

Steve

Lord Lucan · 09-11-2018, 03:06 AM

Originally posted by stevebrot

this site has different measurements between the K2, KM, KX, and K1000. The K1000 is the same as the Spotmatic F except for being a little shorter.

Possibly the K1000 is a little shorter than the Spotmatic F, but whatever it is the KM is the same as the K1000 because the K1000 is simply the KM with some features removed (most significantly the self-timer). The line of evolution was : Spotmatic F ---> KM ---> K1000. Apart from the major change from the Spotmatic's screw mount to the KM's bayonet, other changes were relatively minor I believe.

stevebrot · 09-11-2018, 07:34 AM

Originally posted by Lord Lucan

The line of evolution was : Spotmatic F ---> KM ---> K1000. Apart from the major change from the Spotmatic's screw mount to the KM's bayonet, other changes were relatively minor I believe.

Yes, that is the obvious line of evolution. I suspect the size differences are due to top plate design more than anything else. One would have to compare parts lists to determine actual interchange potential of things like prisms.

Steve

09-02-2018, 01:17 PM	#1
dmjohn1337 New Member Join Date: Sep 2018 Posts: 1	Pentax Film SLR prism compatability 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. Hi all, First time poster, but I have visited this forum many times and have found them to be very helpful! So I have a Pentax K2 that has a desilvered prism. My question is how likely is it that a prism out of another K body (or even a Spotmatic) would work in the K2. Thanks!

09-10-2018, 02:48 PM	#10
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by boriscleto The KX, KM, & K1000 are all the same body though...the KX has different meter... ~~The KX is different size-wise too, though just a millimeter or so here and there.~~ Nope...wrong. It is officially identical dimensions, according to the user manuals. However, this site has different measurements between the K2, KM, KX, and K1000. The K1000 is the same as the Spotmatic F except for being a little shorter. Steve Last edited by stevebrot; 09-10-2018 at 03:08 PM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Compatability of modern Pentax lenses on old (35mm film) Pentax bodies	Origineelreclamebord	Pentax SLR Lens Discussion	20	02-14-2013 10:44 AM
SLR lenses and Digital lens compatability	rgabriel756	Welcomes and Introductions	2	11-16-2012 10:58 AM
Old lenses compatability for digital SLR	pointandshoot	Pentax SLR Lens Discussion	14	05-30-2012 03:20 PM
Suggestion Change name of Film SLR and/or SLR Lens sub-forums	clawhammer	Site Suggestions and Help	4	07-31-2008 06:55 AM

09-02-2018, 02:58 PM	#2
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	I'm pretty sure the K2 used the same prism as the rest of the K series, and the Spotmatic. There was a thread a while back in which the original poster was buying up Spotmatics to cannibalize the prism to refit K1000s for resale.

09-02-2018, 04:10 PM	#3
gofour3 Site Supporter Join Date: Oct 2008 Location: Vancouver, Canada Posts: 8,090	Originally posted by dmjohn1337 Hi all, First time poster, but I have visited this forum many times and have found them to be very helpful! So I have a Pentax K2 that has a desilvered prism. My question is how likely is it that a prism out of another K body (or even a Spotmatic) would work in the K2. Thanks! Best check with Eric, he will know. Not sure about prisms, but he told me once that the focusing screens in a K2 are a different size than a KX/KM/K1000. Phil.

09-02-2018, 11:26 PM	#4
pentaxus Site Supporter Join Date: Jun 2010 Location: Central Coast, CA Posts: 1,313	The focusing screen and prism are a little wider in the K2.

09-03-2018, 04:02 AM	#5
Wild Mark Veteran Member Join Date: Jun 2013 Location: Newcastle Photos: Gallery \| Albums Posts: 1,954	The K2 prism is different to the KX, KM and K1000. I think it is even different to its M42 mount sister - the ESII I have some dead K2 prisms and have compared them to the one linked below as listed on ebay (I am not linked to the seller) Asahi Pentax SLR Sucher Prisma / new finder prism - old stock (NEU) \| eBay It looks like the real deal. Perhaps worth the punt?

09-10-2018, 01:28 AM	#6
Lord Lucan Pentaxian Join Date: Sep 2017 Location: South Wales Photos: Gallery Posts: 2,961	Originally posted by boriscleto There was a thread a while back in which the original poster was buying up Spotmatics to cannibalize the prism to refit K1000s for resale. The K1000 (and the KM) was a Spotmatic F with a bayonet mount, and otherwise only detailed differences, so that is a no-brainer. It would not necessarily apply to the K2 or KX though.

09-10-2018, 01:51 PM	#7
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by boriscleto I'm pretty sure the K2 used the same prism as the rest of the K series, and the Spotmatic. There was a thread a while back in which the original poster was buying up Spotmatics to cannibalize the prism to refit K1000s for resale. One would think, except that the focus screen is larger than other K-series bodies. implying differences in the prism and/or ocular. Steve

09-10-2018, 02:38 PM	#8
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	Originally posted by stevebrot One would think, except that the focus screen is larger than other K-series bodies. implying differences in the prism and/or ocular. Steve I've never even seen a K2, let alone looked through the viewfinder of one, so I guess I should have looked it up The KX, KM, & K1000 are all the same body though...the KX has different meter...

09-10-2018, 02:44 PM	#9
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by boriscleto I've never even seen a K2, let alone looked through the viewfinder of one, so I guess I should have looked it up I have handled one, but my comment was based on a recent camera comparison post from @LesDMess. The image below was rather enlightening... Steve

09-11-2018, 03:06 AM	#11
Lord Lucan Pentaxian Join Date: Sep 2017 Location: South Wales Photos: Gallery Posts: 2,961	Originally posted by stevebrot this site has different measurements between the K2, KM, KX, and K1000. The K1000 is the same as the Spotmatic F except for being a little shorter. Possibly the K1000 is a little shorter than the Spotmatic F, but whatever it is the KM is the same as the K1000 because the K1000 is simply the KM with some features removed (most significantly the self-timer). The line of evolution was : Spotmatic F ---> KM ---> K1000. Apart from the major change from the Spotmatic's screw mount to the KM's bayonet, other changes were relatively minor I believe.

09-11-2018, 07:34 AM	#12
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Lord Lucan The line of evolution was : Spotmatic F ---> KM ---> K1000. Apart from the major change from the Spotmatic's screw mount to the KM's bayonet, other changes were relatively minor I believe. Yes, that is the obvious line of evolution. I suspect the size differences are due to top plate design more than anything else. One would have to compare parts lists to determine actual interchange potential of things like prisms. Steve