Where can I get a Pentax Spotmatic pentaprism?

P

puggie

Suspended / Banned
Messages
889
Name
Bill
Edit My Images
Yes
I have a pentax Spotmatic ESII with a ragged line accross the bottom of the viewfinder. I've opened it all up and found the pentaprism is beginning to de-silver on the back. So I want a replacement pentaprism, anyone know where I may find one (or does anyone have a duff spotmatic in their loft).

at the moment Its looking like a mini waist level finder slr :)
 
If theres any chance of getting one, look here:

http://www.asahiphoto.co.uk/

They brought all of Pentax's old spares, parts etc. They do have a shop where you can buy things like focusing screens but nothing like a whole pentaprism.
Contact them about if they can help you. If they say you need to send it into them (which is likely) then take it from me, their repair service is top notch, I got my dads Pentax SMC-A 50mm f1.7 repaired by them and they did an outstanding job.

Spotmatic pentaprisms are all the same across the entire range though so you may be able to get one out of a broken one but I doubt it'll work very well as any tolerences with position etc are likely to be a bit suspect.
 
I did email them last night. It looks like I may have got one for the cost of postage from a very kind member of another forum (Pentaxuser.co.uk). The prism is very simply fixed and there should be no alignment issues, all its doing is bending the viewfinder image round 90deg, exposure measurement and everything else is done prior to the pentaprism on the focusing screen. its just held on by 2 grub screws and a pair of springs the design is self aligning.

I'll let you know how i get on.
 
This is the problem on the back of the prism:

IMG_5964.JPG


And this is how it shows up in the viewfinder:

IMG_5970.JPG


Waist level conversion???

IMG_5966.JPG


IMG_5968.JPG
 
Last edited:
Does the pentaprism have the shutter speeds/lightmeter galvanometer needle on it or is it on the focusing screen? From your pictures it looks like its not on the screen. If its on the prism then you will need one for an ESII as only them have one like that.

showphoto.php
[/url][/IMG]

Sorry about the somewhat bad picture (its from a poorly scanned manual on Pentax's website) but thats what I am talking about and it should look like.

How much did you get the ESII for by the way? (I wouldn't mind one either!)

EDIT: Just noticed that it is on the focusing screen in your pictures, I was looking on the wrong side as I forgot that it would be on the left not right as its reversed by the pentaprism.
 
Last edited:
Yep, its all on the focusing screen the all the prism does is bend the image for the viewfinder, this is why I think the spotmatics will be all interchangeable I should know one way or the other by the weekend.

The ESII was bought with the view finder issue known from US ebay (but my thinking was it must be a simple optical fault. didn't affect the pics). I think it was £102 delivered from the states and customs hit me for another £22 (which I was hoping to avoid :( ) but it did come with a mint SMC 50mm f1.4 lens, the later 8 blade aperture version, which normally go for nicely over a ton over here. the Camera is mint though, no scratches or brass showing anywhere.

worth noting that Ashaiphoto will not touch them for repairs, so if your buying make sure its a good one, the Spotmatic F is probably the better option in the long term (which is fine as I bought one of those too :))
 
The parts are near impossible to get these days as the electronics are the main problem usually and use completely obsolete and hard to get components. I don't see why the pentaprism would be an issue though.

This place might do for you if you can't do it yourself, but the cost (£76.00) is almost the entire price you paid although it is for a full CLA service. Once again its subject to parts though.

http://harrowtechnical.co.uk/repair-prices/
 
apparently Spot F and K1000 prisms are drop in replacements :)

might 'borrow' the prism out of my F tomorrow to see.
 
Just get a cheap or broken K1000 then and steal the prism out of that, please don't go taking a Spotmatic F apart. I can't bear to think of it as their such wonderful classics.

EDIT:

Seems broken K1000's don't exist on ebay but there is a broken Spotmatic F with an intact pentaprism here:

http://cgi.ebay.co.uk/Pentax-Spotmatic-F-w-55mm-F2-Lens-Parts-Repair-/230523121227?pt=Film_Cameras&hash=item35ac3fae4b

Its in the states but I don't imagine postage would be too much. The only slight sort of problem is that its marked 'Honeywell Pentax' not 'Asahi Pentax' as Honeywell were the US importers. However you should be able to use a Pentaprism from a KM, KX or K2 as well as they are essentially the same body as the K1000 with just less features.
 
Last edited:
Well I fitted the plain old spotmatic prism to the ESII and despite being fractionally different on the corners, its fits fine and looks fine and seems to work ok.

Just need to get the rest of it back together and I'll run a roll of film through it this weekend.
 
You must log in or register to reply here.
Back
Top