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02-04-2019, 04:23 AM   #1
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aperture problems k 30-- a lenses

My K 30 suffers occasionally of the well known aperture problem. . I have tried to use it with a tamron 70 - 300 mm macro with an aperture ring. I set it on a fully open aperture and AF.
It seems to work well . Can I rely on that every time ?
The reason I ask is that I will lend it to A youngster in the family that wants to photograph animals. He is a week boy that does not deserve too many problems. In this case we want reliabel exposure and AF, its is a minor matter that maximum aperture does not give optimum sharpness . regards

02-04-2019, 04:49 AM   #2
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if you know that the K-30 you have suffers from the aperture block failure issue, you know that you are not going to get reliable exposure unless you are in full manual mode...

that's the entire problem with the aperture block failure...
02-04-2019, 05:38 AM   #3
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As you have an aperture ring on the Tamron lens, try it out with manually chosen apertures, forget about using the A setting. While I am not familiar with the K-30 (and K-50) aperture problem I seem to remember reading somewhere in the forum that the camera will correctly expose. Otherwise as suggested by pepperberry farm, use it fully manual.
02-04-2019, 07:51 AM   #4
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Teach him Green Button mode and use the camera in manual with aperture ring only lenses. Give him some sunny 16 tutorials and a gray card. Let him know about exposure triangle etc.

BTW - what's a WEEK boy?

Also will he be using raw or jpg? If shooting in RAW he has a lot of latitude for shadow recovery so a little bit of underexposure to avoid blown highlights is not a bad thing.

02-04-2019, 08:18 AM   #5
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QuoteOriginally posted by UncleVanya Quote
Teach him Green Button mode and use the camera in manual with aperture ring only lenses. Give him some sunny 16 tutorials and a gray card. Let him know about exposure triangle etc.

BTW - what's a WEEK boy?

Also will he be using raw or jpg? If shooting in RAW he has a lot of latitude for shadow recovery so a little bit of underexposure to avoid blown highlights is not a bad thing.
He has in some aspects - but not all- limited capacities. Therefore the handling must be VERY simple, automatic ISO,jpeg, full manuel aperture and av. All other opportunities are out of reach.That's what worked for me and I hope that this solution is stable, since the solenoid has no work to do.
Normally i go for max quality, but less than that will make him rather happy.
02-04-2019, 08:38 AM   #6
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QuoteOriginally posted by niels hansen Quote
He has in some aspects - but not all- limited capacities. Therefore the handling must be VERY simple, automatic ISO,jpeg, full manuel aperture and av. All other opportunities are out of reach.That's what worked for me and I hope that this solution is stable, since the solenoid has no work to do.
Normally i go for max quality, but less than that will make him rather happy.
So weak not week, gotcha. AV and full manual aperture is only going to work with M42 lenses but I think you mean something else? I'm not aware of any way to make AV mode work with a K mount using the aperture ring on modern digital bodies.

It seems to me you'd be better off getting a functioning body for him or repairing it. Wide open on sunny days will be a challenge - there are exposures you just can't take without stopping down some.

---------- Post added 02-04-19 at 10:45 AM ----------

Rereading this. If the lens is sufficiently slow and the conditions permit the exposure - yes AF and wide open should be consistent using the K-30 with the aperture block failure... for a while. Reports do tend to suggest that over time the ultimate result is that the shutter will also fail but that takes time.
02-04-2019, 09:16 AM   #7
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An AF lens with an aperture ring using the ring in green button manual mode would be a compromise. You would be looking at some of the older lenses or some of the third party offerings with aperture rings.

A fully functioning body would be best. Green/Program and all other modes would work properly with AF lenses.
02-04-2019, 09:29 AM   #8
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QuoteOriginally posted by niels hansen Quote
My K 30 suffers occasionally of the well known aperture problem. . I have tried to use it with a tamron 70 - 300 mm macro with an aperture ring. I set it on a fully open aperture and AF.
It seems to work well . Can I rely on that every time ?
The reason I ask is that I will lend it to A youngster in the family that wants to photograph animals. He is a week boy that does not deserve too many problems. In this case we want reliabel exposure and AF, its is a minor matter that maximum aperture does not give optimum sharpness . regards
Yes, it will work reliably every time.

The camera meters wide open, so if you set the aperture to "wide open", metering will match photograph actually taken; green button metering is needed only when you have set aperture to a smaller opening.

As mentioned, you will get reduced DOF, but if you can "live with" that .....

I took the example photo in our backyard a few minutes ago (*).
The only "PP" was to down-scale for display here.

I used a Pentax-FA 28-105mm f/3.2-4.5 lens set at f/3.2 and Av mode on my K-30 {which now suffers from DIS}.


(*) Actually, I took half-dozen photos of various scenes, but one is enough for this

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Last edited by reh321; 02-04-2019 at 09:37 AM.
02-04-2019, 09:34 AM   #9
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QuoteOriginally posted by UncleVanya Quote
Reports do tend to suggest that over time the ultimate result is that the shutter will also fail but that takes time.
I believe, but do not know, that the shutter failures are a result of using short bursts to restore operation during the early days when Dark Image Syndrome first appears {for the first few images}
02-04-2019, 02:37 PM   #10
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QuoteOriginally posted by reh321 Quote
I believe, but do not know, that the shutter failures are a result of using short bursts to restore operation during the early days when Dark Image Syndrome first appears {for the first few images}
I disagree - but again I don't know this for certain. I just recall reading that the solenoid for aperture and something else shutter related is tied together in the low end shutter/aperture block and handled with separate solenoids in the high end systems like a K-3. I will try to dig that up but it's a needle in a haystack issue. I have been unable to find this and hope that someone else recalls where it is documented.
02-04-2019, 08:10 PM   #11
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QuoteOriginally posted by niels hansen Quote
My K 30 suffers occasionally of the well known aperture problem. . I have tried to use it with a tamron 70 - 300 mm macro with an aperture ring. I set it on a fully open aperture and AF.
It seems to work well . Can I rely on that every time ?
The reason I ask is that I will lend it to A youngster in the family that wants to photograph animals. He is a week boy that does not deserve too many problems. In this case we want reliabel exposure and AF, its is a minor matter that maximum aperture does not give optimum sharpness . regards
After understanding what is happening, in my opinion, I think the best way to go would be a used body. After seeing other threads about the ABF, it seems, sooner or later it will fail completely leaving you with a camera that can only be used in manual.Thinking about your situation, I do not believe that would be good thing.

Just doing a quick search, I found this; Pentax K-7 Digital SLR Camera Body {14.6 M/P} at KEH Camera

I do not know if you can do this, there is also getting your K30 repaired too.
02-07-2019, 03:24 AM   #12
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Thank you for all the answers, here are my reactions
I am retired and on a rather limited pension so I cannot afford a professionel repair, in Denmark it is very expensive .So is another body. I don't think I have the skills for DUI.
I don't agree with uncle vanya that there is a risk of overexposing : the k 30 shutter is fast enough to avoid this if you use auto iso.
I like reh321 s statement which I find logically, and the easiest and cheapest solution. I HOPE that uncle vanya is not right concerning the connection between the two solenoids, and I HOPE that the matter wont be worse as stated by several others.
I will test the camera together with the boy on av, auto iso and max aperture manual from the aperture ring.I guess that 500 poses will give an answer Time will show. I will let you know
02-07-2019, 06:09 AM   #13
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QuoteOriginally posted by niels hansen Quote
Thank you for all the answers, here are my reactions
I am retired and on a rather limited pension so I cannot afford a professionel repair, in Denmark it is very expensive .So is another body. I don't think I have the skills for DUI.
I don't agree with uncle vanya that there is a risk of overexposing : the k 30 shutter is fast enough to avoid this if you use auto iso.
I like reh321 s statement which I find logically, and the easiest and cheapest solution. I HOPE that uncle vanya is not right concerning the connection between the two solenoids, and I HOPE that the matter wont be worse as stated by several others.
I will test the camera together with the boy on av, auto iso and max aperture manual from the aperture ring.I guess that 500 poses will give an answer Time will show. I will let you know
To be clearer, what I recall (but can't find) was that eventually untreated the solenoid stops operating the shutter but since others are using their bodies for a long time... Perhaps I'm misremembering.
02-07-2019, 01:00 PM   #14
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QuoteOriginally posted by UncleVanya Quote
To be clearer, what I recall (but can't find) was that eventually untreated the solenoid stops operating the shutter but since others are using their bodies for a long time... Perhaps I'm misremembering.
I hope so
02-11-2019, 01:34 AM - 1 Like   #15
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500 poses with Tamron 70 - 300mm on av, auto iso and AF and manually max fstop are all ok. I return if that changes
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