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08-22-2019, 09:08 AM   #31
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QuoteOriginally posted by bdery Quote
He decided to pay for repairs, using services provided by PentaxCameraRepairs which had been recommended by several people. As we are in Canada, shipping back and forth was complicated but relatives traveling to the US helped us.

The camera worked fine for a good while, now it started acting up again
QuoteOriginally posted by MarkJerling Quote
If you replace the solenoid with the white (made in Japan) solenoid, then the camera will be repaired. Replacing the green solenoid with another green solenoid will mean that the replacement green solenoid may fail too.
Therein lies the question. Rumor has it that PentaxCameraRepairs uses salvage parts from known good body types (assumed to be white solenoids). If @bdery 's brother-in-law's camera is showing symptoms again, then might the problem be more complex than the solenoid?


Steve

08-22-2019, 01:01 PM   #32
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QuoteOriginally posted by stevebrot Quote
Therein lies the question. Rumor has it that PentaxCameraRepairs uses salvage parts from known good body types (assumed to be white solenoids). If @bdery 's brother-in-law's camera is showing symptoms again, then might the problem be more complex than the solenoid?


Steve
I I understand it correctly, then the official repairers use the green solenoid for the repair. But, you're right, if a white solenoid was used for the repair, then there may be another problem. But, until he tries, he won't know.
08-23-2019, 12:50 AM - 1 Like   #33
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QuoteOriginally posted by MarkJerling Quote
If I understand it correctly, then the official repairers use the green solenoid for the repair.
This is the case and some apply the sanding method now instead of replacing it with the green solenoid.
Because it is even cheaper and often the camera functions for about a year.


QuoteOriginally posted by MarkJerling Quote
QuoteOriginally posted by stevebrot Quote
Rumor has it that PentaxCameraRepairs uses salvage parts from known good body types (assumed to be white solenoids). If @bdery 's brother-in-law's camera is showing symptoms again, then might the problem be more complex than the solenoid?
But, you're right, if a white solenoid was used for the repair, then there may be another problem. But, until he tries, he won't know.
I daubt this very much because:

1. To salvage an old body is quite some work, about half an hour.
2. It involves quite some work to find old bodies and thus already costs much more than the green solenoid
3. There are not enough cameras out there to salvage.

4. There is almost zero chance that the white solenoid is going to be manufactured again in Japan!


In Europe the official repairers in most cases deny their customers to built in the white solenoid if the customer delivers it!
And some still play the issue down, speak of mass-hysteria in the forums.

It is simply the most comfortable way to replace the green solenoid or ... presenting oneself very fashionable under the umbrella of sustainability:
To sand/file/grind the plunger of the horseshoe

Last edited by photogem; 08-25-2019 at 09:08 AM.
08-23-2019, 02:11 AM   #34
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QuoteOriginally posted by stevebrot Quote
Leaving the solenoid out of the discussion (sort of a red herring when doing diagnosis), the expected actions run like this:
  • Body set to control to maximum aperture -- coupling on body remains stationary*
* This has to do with how the "A" contact encoding works. Wide open, regardless of f-number, is always no-action.
Nah-nah..nah....nah....... nah:

We won't leave the solenoid out of the discussion because:

1. it is the very opposite of a red hering when doing diagnosis
2. because "wide open" the solenoid does act!

When I repair a camera and it is open on my workbench, I can see how of if the solenoid acts! This is... well: Diagnosis in real life!

When the camera is repaired, i.e. the faulty solenoid is changed, I always do a test ....

kind of double wide open:

a) the camera is still wide open, i.e. frontpart, bottompart and sidepart removed
b) aperture is set to f 1.7 on my SMC Pentax F50/1,7 which I use for tests


and voila:

The solenoid does act/switch in f1,7 = wide open on this lens

Steve, it seems to me you speak from guessing but have you yet opened a K30 with a stuck solenoid, tested it, changed the solenoid so that those assumptions are no longer such but real life observations?!

08-23-2019, 09:48 AM   #35
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QuoteOriginally posted by photogem Quote
kind of double wide open:

a) the camera is still wide open, i.e. frontpart, bottompart and sidepart removed
b) aperture is set to f 1.7 on my SMC Pentax F50/1,7 which I use for tests


and voila:

The solenoid does act/switch in f1,7 = wide open on this lens
Interesting. I am glad are able to test rather than guess. I have actually witnessed normal operation of the actuator when set to full open.* It moves not, though on a defective camera it moves (duh). Explain how if the solenoid acts/switches, why the actuator does not move. Your observations have caused me to suspect there is more to this problem than just a solenoid and that there is misunderstanding of its role.


Steve

* Easily done if one has an Adaptall-2 PKA adapter to mount without lens attached.

BTW, Nah-nah..nah....nah....... nah is beneath you.

Last edited by stevebrot; 08-23-2019 at 10:18 AM.
08-23-2019, 10:41 AM   #36
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QuoteOriginally posted by stevebrot Quote
Interesting. I am glad you are able to test rather than guess. I have actually witnessed normal operation of the actuator when set to full open.* It moves not, though on a defective camera it moves (duh). Explain how if the solenoid acts/switches, why the actuator does not move. Your observations have caused me to suspect there is more to this problem than just a solenoid and that there is misunderstanding of its role.


Steve

* Easily done if one has an Adaptall-2 PKA adapter to mount without lens attached.
This is the wrong approach.
You can only test the solenoid in action with a lens installed. It won't act without a lens.

I tried to explain how the solenoid with all the other linked parts works HERE

Also: Optical pre-view will not work if the solenoid is stuck.


Best to try it by testing it oneself with an open Pentax with a functioning solenoid.

(or better, with a non-functioning solenoid and then replacing it to see the difference)


Very cheap, an old Pentax *ist or K100D or similar, even a K10D.

The Adapt-All adapter doesn't substitute a lens, it is what it is, an adapter.

The usual aperture-diphragm-control-unit-solenoid-dark-exposure-problem is

solely due to the stuck plunger of the solenoid

This has been proven now many times and I don't quite understand why you still negate/deny this?

But further problems are possible if one doesn't solve it the right way:
If one tries to force the solenoid to work or tampers the wrong way with it, it can bring the mechanisms linked with it out of alignement.
Then one has to learn how to align the complect mechanisms if not further damaged (which sometimes happens).


Further study you find in older Pentax Service manuals such as for the K10D, K20D etc.



In all of those the exact adjustment is shown:

Last edited by photogem; 08-25-2019 at 09:19 AM.
08-24-2019, 05:29 PM   #37
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QuoteOriginally posted by photogem Quote
Wrong approach.

I tried to explain how the solenoid with all the other linked parts works HERE
Thank you for the helpful link. The explanation there goes a long way to explaining how this all works and getting a broader understanding of how there might be premature failure of the solenoid component similar to photos you have shared in the past.


Steve
6 Days Ago   #38
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I repaired my K30 2 years ago with the flash solenoid from an MZ-30. The aperture works 100% of the time with AAs even out in the cold doing astro (down to depletion a couple of times). I used Lidl Tronic 2400s and now Eneloops as they last longer.

If I use the official or third party li-ion I get aperture failure 50% of the time.

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