K-70 underexposure...appears to be the stuck solenoid.

**photogem** · 04-15-2021, 10:06 AM

Originally posted by FozzFoster

Originally posted by jon.partsch

Also, I think the prevailing theory is that cameras manufactured after 2015 didn't have the *really* bad solenoid, just a mediocre one. The problem is considered rare in K70s and thought only to impact the early ones - be sure to check the manufacturer date of your camera

I didn't know this - thanks for the info - checked my K-70 and it was manufactured in 2020! Glad I didn't get old stock. But I guess 'mediocre' isn't very comforting. I do have extended warranty though as well

Now, not that we get another internet-fairytale...
when was the Pentax K70 introduced?

Good source is THIS ONE

**tonyzoc** · 04-17-2021, 04:57 PM

Make sure you get/have an electric soldering pen with a fine point. Don't use a butane type. You need a fine point tweezers and a set of JIS screw drivers. I botched my K-S2 repair probably because I had a poor butane soldering pen. When I fixed my K-70 I had a temp adjustable electric soldering pen and the repair was easy and my K-70 has been working great ever since.

DMITRY1 · 04-18-2021, 07:02 AM - **1 Like**

I bought a JIS 000 screwdriver and a Xuron 450 fine needle nose plier. I will be using a soldering iron with a pen tip; I don’t have a soldering pen. Waiting for the solenoid to arrive.

DMITRY1 · 04-25-2021, 02:12 PM - **2 Likes**

I just finished replacing the solenoid. The most time-consuming part was unscrewing and screwing back together the body housing. Overall this was a fairly easy job, and took about an hour to finish.
Thank you, photogem, for he explicit and indispensable tutorial!!! This job wouldn't be possible without it.
I did manage to drop a screw inside the body cavity, and when i was shaking it to have it drop out, a small plastic washer fell out from somewhere inside the camera, along with the lost screw. Didn't bother looking where it came from, just wanted to mention it.
Also, the screw head holding the green solenoid was secured with some locking compound, and was a bit of a bugger to loosen.
I purchased this JIS #000 screwdriver. Moody Tools - Screwdriver, JIS Type S #000 Pollicis - 51-2063 - Phillips Head Screwdrivers - amazon.com?tag=pentaxforums-20& I didn't want to use a cheap Chinese screwdriver.
The aperture works fine now.

reh321 · 04-28-2021, 06:37 AM - **1 Like**

Originally posted by DMITRY1

Camera is 3 years old. Only 3,200 actuations.

I purchased my KP in 11-2018, but PF's "shutter count tool"
Check Camera Shutter Count and Manufacture Date
says it was built a complete year earlier.

Did you happen to record the "built date" also?
I was thinking it might have come from old stock; we received many "Dark Image Syndrome" reports at one time, but they seem to have tailed off now.

DMITRY1 · 05-01-2021, 01:41 PM - **1 Like**

Originally posted by reh321

I purchased my KP in 11-2018, but PF's "shutter count tool"
Check Camera Shutter Count and Manufacture Date
says it was built a complete year earlier.

Did you happen to record the "built date" also?
I was thinking it might have come from old stock; we received many "Dark Image Syndrome" reports at one time, but they seem to have tailed off now.

Shutter Count 3,309
Manufacture Date 2017:11:07

Nothing to be proud of, Pentax, but at least it cost me less than $80 including the new solenoid and the screwdriver to get it going. Thanks again to photogem !!!

DMITRY1 · 05-02-2021, 07:42 PM

Interesting...after I replaced the solenoid, my lenses are now overexposing by 3 stops. This didn't happen before the solenoid went bad...
What are your suggestions?

**photogem** · 05-03-2021, 12:19 AM

First do a complete reset and try again.
Usually this will solve it.

Tthen check again.
If it continues, up-load photos with EXIF-Data.

I was not able to answer for a week, so here some additionals:

Your shuttercount proves again:

- Low shutter count
+
- not used for a while ...... is often one of the reasons why ABF happens.

The "left-over" plastic washer belongs to the microphone-socket.

I cannot alter the tutorial anymore in this section, but we had this problem plus another washer with the K-S2 which is almost identical for the repair, see HERE on page-2 of the K-S2 tutorial

DMITRY1 · 05-03-2021, 06:26 AM

The first one is manual mode.
Second is in auto. The auto mode image is more accurate. Manual mode image is overexposed.

mtkeller · 05-03-2021, 06:41 AM

Those are essentially the same exposure. One has the aperture 1+1/3 stops wider, but it also has the shutter speed 1+1/3 stops faster.

**photogem** · 05-03-2021, 11:34 PM

@DMITRY1

id you do a reset?
And then try in Av and Tv modes

**clackers** · 05-03-2021, 11:55 PM - **1 Like**

Originally posted by DMITRY1

The first one is manual mode.
Second is in auto.

?

There are not three stops difference between the two, Dmitry!

DMITRY1 · 05-04-2021, 05:17 AM

I take a lot of photos with studio lighting in manual mode, using soft boxes for illumination.
The first one is in M-mode. The EV bar scale was zero'ed, but the image is noticeably overexposed.
The second one is in AUTO-mode. Other than the White Balance, the exposure is correct.

I did the reset prior to taking these frames.

**clackers** · 05-04-2021, 06:21 PM

Again, Dmitry, these are two photos with entirely different settings, and they are not three stops apart.

Not a Number · 05-04-2021, 07:58 PM

Take a photo in auto. Change to manual and dial in those settings including ISO and take a photo of the same subject.

05-03-2021, 11:34 PM	#26
photogem Site Supporter Join Date: Apr 2015 Posts: 3,522	@DMITRY1id you do a reset? And then try in Av and Tv modes

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04-15-2021, 10:06 AM	#16
photogem Site Supporter Join Date: Apr 2015 Posts: 3,522	Originally posted by FozzFoster Originally posted by jon.partsch Also, I think the prevailing theory is that cameras manufactured after 2015 didn't have the really bad solenoid, just a mediocre one. The problem is considered rare in K70s and thought only to impact the early ones - be sure to check the manufacturer date of your camera I didn't know this - thanks for the info - checked my K-70 and it was manufactured in 2020! Glad I didn't get old stock. But I guess 'mediocre' isn't very comforting. I do have extended warranty though as well Now, not that we get another internet-fairytale... when was the Pentax K70 introduced? Good source is THIS ONE

04-17-2021, 04:57 PM	#17
tonyzoc Loyal Site Supporter Join Date: Jul 2018 Posts: 992	Make sure you get/have an electric soldering pen with a fine point. Don't use a butane type. You need a fine point tweezers and a set of JIS screw drivers. I botched my K-S2 repair probably because I had a poor butane soldering pen. When I fixed my K-70 I had a temp adjustable electric soldering pen and the repair was easy and my K-70 has been working great ever since.

04-18-2021, 07:02 AM - 1 Like	#18
DMITRY1 Junior Member Join Date: Jan 2018 Posts: 41 Original Poster	I bought a JIS 000 screwdriver and a Xuron 450 fine needle nose plier. I will be using a soldering iron with a pen tip; I don’t have a soldering pen. Waiting for the solenoid to arrive.

04-25-2021, 02:12 PM - 2 Likes	#19
DMITRY1 Junior Member Join Date: Jan 2018 Posts: 41 Original Poster	I just finished replacing the solenoid. The most time-consuming part was unscrewing and screwing back together the body housing. Overall this was a fairly easy job, and took about an hour to finish. Thank you, photogem, for he explicit and indispensable tutorial!!! This job wouldn't be possible without it. I did manage to drop a screw inside the body cavity, and when i was shaking it to have it drop out, a small plastic washer fell out from somewhere inside the camera, along with the lost screw. Didn't bother looking where it came from, just wanted to mention it. Also, the screw head holding the green solenoid was secured with some locking compound, and was a bit of a bugger to loosen. I purchased this JIS #000 screwdriver. Moody Tools - Screwdriver, JIS Type S #000 Pollicis - 51-2063 - Phillips Head Screwdrivers - amazon.com?tag=pentaxforums-20& I didn't want to use a cheap Chinese screwdriver. The aperture works fine now.

04-28-2021, 06:37 AM - 1 Like	#20
reh321 Pentaxian Join Date: Nov 2014 Location: South Bend, IN, USA Photos: Gallery \| Albums Posts: 23,181	Originally posted by DMITRY1 Camera is 3 years old. Only 3,200 actuations. I purchased my KP in 11-2018, but PF's "shutter count tool" Check Camera Shutter Count and Manufacture Date says it was built a complete year earlier. Did you happen to record the "built date" also? I was thinking it might have come from old stock; we received many "Dark Image Syndrome" reports at one time, but they seem to have tailed off now.

05-01-2021, 01:41 PM - 1 Like	#21
DMITRY1 Junior Member Join Date: Jan 2018 Posts: 41 Original Poster	Originally posted by reh321 I purchased my KP in 11-2018, but PF's "shutter count tool" Check Camera Shutter Count and Manufacture Date says it was built a complete year earlier. Did you happen to record the "built date" also? I was thinking it might have come from old stock; we received many "Dark Image Syndrome" reports at one time, but they seem to have tailed off now. Shutter Count 3,309 Manufacture Date 2017:11:07 Nothing to be proud of, Pentax, but at least it cost me less than $80 including the new solenoid and the screwdriver to get it going. Thanks again to photogem !!!

05-02-2021, 07:42 PM	#22
DMITRY1 Junior Member Join Date: Jan 2018 Posts: 41 Original Poster	Interesting...after I replaced the solenoid, my lenses are now overexposing by 3 stops. This didn't happen before the solenoid went bad... What are your suggestions?

05-03-2021, 12:19 AM	#23
photogem Site Supporter Join Date: Apr 2015 Posts: 3,522	First do a complete reset and try again. Usually this will solve it. Tthen check again. If it continues, up-load photos with EXIF-Data. I was not able to answer for a week, so here some additionals: Your shuttercount proves again: - Low shutter count + - not used for a while ...... is often one of the reasons why ABF happens. The "left-over" plastic washer belongs to the microphone-socket. I cannot alter the tutorial anymore in this section, but we had this problem plus another washer with the K-S2 which is almost identical for the repair, see HERE on page-2 of the K-S2 tutorial

05-03-2021, 06:41 AM	#25
mtkeller Veteran Member Join Date: Feb 2019 Location: Sioux City, IA Photos: Gallery Posts: 938	Those are essentially the same exposure. One has the aperture 1+1/3 stops wider, but it also has the shutter speed 1+1/3 stops faster.

05-03-2021, 11:55 PM - 1 Like	#27
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by DMITRY1 The first one is manual mode. Second is in auto. ? There are not three stops difference between the two, Dmitry!

05-04-2021, 06:21 PM	#29
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Again, Dmitry, these are two photos with entirely different settings, and they are not three stops apart.

05-04-2021, 07:58 PM	#30
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	Take a photo in auto. Change to manual and dial in those settings including ISO and take a photo of the same subject.