Pentax S1a/H1a mirror problem

[terry_scott]

I've just this morning received a black Asahi Pentax S1a (they were

the H1a in the States) by mail order. Cosmetically, it's very good.

And it works except -- the mirror does something odd.

 

It goes up as usual but, after the shutter curtains have finished

travelling, stays up for nearly one second before dropping down.

 

Okay, the camera's 40 years old or so but my other Pentax S1a (a

chrome one) doesn't do this.

 

Does anyone know whether this is a symptom of something awful yet to

come?

 

I can reject the camera, return it to the dealer, but would like to

keep it if the dealer can fix it properly. I'd like opinions on

whether, if the mirror were fixed, something else "in back of it" is

wrong that might develop in due course.

 

I'd appreciate any advice.

[michael_linn]

The dropping of the mirror is triggered by the second curtain completing it's travel in a normal manner. Your problem may be caused by the second curtain not having enough momentum due to old lubrication or weak spring tension. In this case, the mirror is not the only problem- the shutter speeds will likely be off also. Luckily, it's a well made camera which is easily repaired. Many camera repair technicians (beyond a certain age) were originally trained on this actual camera. This one needs a clean, lube, and adjustment.

[valen]

<p>Well, obviously something is wrong. If the camera is otherwise in good condition it can probably be fixed though. If the seller claimed it was in working condition he should be willing to take it back or fix it.</p>

 

<p>I also have an S1a that belonged to my father. A couple of years ago the shutter started sticking so that only half the frame was exposed. I sent it to John Titterington who fixed it for a reasonable cost. If you really like the camera you could consider having him give you an estimate on repairing it. It might just need a CLA.</p>

 

<p>Here's John's URL: </p>

 

<a href="http://www.geocities.com/~titterington/camera-repair/">http://www.geocities.com/~titterington/camera-repair/</a>

[connealy]

If it is like my Spotmatic, there is a small strip of light seal where the end of the mirror comes up to the body. Might be worth checking that to see if it is old and sticky. If so, it is easy to replace. If the camera has never been serviced, you may need light seals all around anyway.

[terry_scott]

Thank you all for your advice. Much appreciated. Agreed: a camera this old would surely benefit from a Clean-Lubricate-Adjust. This morning I exposed a roll of Pan F in the S1a to check speeds, curtain travel and so forth - right now, the film is in a developing tank and I'll be processing it this evening. That will let me consider whether a CLA is vital or simply desirable.

 

The matter of the second curtain interests me too. With the back cover open, transit seems smooth and sure, though. I'll mark that as a maybe if the next item doesn't work out.

 

I'm hoping that attention to the foam strip in the top-front of the mirror box will cure things. (Back to the dealer's repairman.) I have a thought as to how this might be checked.

 

The idea is for me to find a thin piece of paper, cut it to size, and place it over the foam strip to prevent contact between the mirror and the (sticky?) strip when the shutter is fired. Then fire the shutter (camera upside down to keep the paper in).

 

This should tell me whether the foam strip is the problem. If the mirror flips down as it should... If it doesn't, back to square one.

[terry_scott]

This morning, I fired the S1a normally. Then I held it upside down and fired it.

 

Result: upside down, it took several seconds before the errant mirror flicked back down. That's different!

 

Tried it around again, normal way up then upside down, and got the same effects.

 

This does suggest to me that the foam strip is the problem. Any further ideas?