All Forum Comments
Comment by VividArt posted on Is this the reason why SDM lenses need to be used often and are prone to fail? at 02/08/2016 - 12:37
Good topic David.
I have read as much as I could dig up on the subject, I too own the 50-135 and worry..
I had an unexpected shutter click the other day on my K52s. I had just mounted the lens, was half pressing and the mirror flapped as if it was taking a shot..
No shot was taken by the camera.
I pull mine off the shelf every few months and keep using it as has been suggested. My dry fired shot was the only incident that day, I was chasing airplanes at full zoom and it worked fine for the few hundred shots I took that day.
Related? Likely not, but could have been that the lens was not firmly attached. It was, but I re clicked it into place after the failed shot just to be sure and all was well for the rest of the day..
A note on the causes I've read, likely you have seen these as well but it's worth mentioning.
I read that they used a type of grease in the lens that gets dried up, causes the motor to "load" unnecessarily against the resistance the dried grease offers, this strain on the motor will ask more of the capacitor(s) and will attempt to overcome the resistance eventually leading to the actual motor failing.
The capacitor thing is another can of worms that not many people have heard of.
The story goes: A design for a series of efficient capacitors was "stolen" by a foreign country that has since taken over the market in electronics. You know who...
What I have heard in the electronics industry is that the formula was stolen but was incomplete..
Millions of capacitors were made with this botched formula, they were then used in all electronics across the planet including Japan.
Every kind of device got them for a period of almost 20 yrs, they are poorly made and they often burst. I have changed many of these myself, the types of devices I've seen them in have been top shelf Japanese made pc mother boards, all audio equipment made by Korg, Tascam, Lexicon, Motu, the list goes on and on.
There are thousand of threads out there on the stupid capacitors, they made it into everything. I wouldn't be surprised if they were used to save money on the lenses..
A capacitor should bleed itself within 24 hrs usually, but the instant the camera is turned on, the lens is also fired up electronically - this should recharge a good capacitor at the speed of light.
The new capacitors made with graphine, that replace batteries keep their charge for a very long time.
But when the lens pause's as your lens did, I would imagine that the capacitor has begun to leak it's electrolyte and it's capacity has become diminished causing a vague connection to the rest of the electronics including the motor controller or the other mythical grease issue.
In some cases allowing the equipment to warm up will recharge a dying capacitor but it will effect the performance of the lens or device. I have to replace 12 big ones in a Tascam DM-24 digital mixer that needs a half hour to warm up, the first half hour sounds like static or fried speakers. After the warm up it's very usable but those capacitors are bulging and waiting to burst, I don't use the mixer at this point in time...
On a positive note, the lens can be converted to screw drive by hacking the firmware, I read that doing so before the motor dies is best, other wise the lens might need to be taken apart to free up the sticky motor first..I hear they track faster than SDM..
Then they said they switched to a new motor...? Who knows. The capicitor thing I have seen personally many times and know that they were used extensively..Pentax is pretty hush hush about what they actually fix when something goes bad, likely they didn't know about the capacitors until well after the lenses were designed and sold. Not really the sort of thing anybody would want to admit to..
It's an upsetting topic, I love the lens, can't imagine not having it in my kit. I bought mine almost three years ago, even making sure I bought one that was not in the flagged serial number list, the extended warranty I bought gets me another two years. Here's to hoping right along with my camera bodies and whatever else I own that has them in it.. :-/
Good luck with yours. I hope the info was somewhat helpful.
Regards,
Damien
I have read as much as I could dig up on the subject, I too own the 50-135 and worry..
I had an unexpected shutter click the other day on my K52s. I had just mounted the lens, was half pressing and the mirror flapped as if it was taking a shot..
No shot was taken by the camera.
I pull mine off the shelf every few months and keep using it as has been suggested. My dry fired shot was the only incident that day, I was chasing airplanes at full zoom and it worked fine for the few hundred shots I took that day.
Related? Likely not, but could have been that the lens was not firmly attached. It was, but I re clicked it into place after the failed shot just to be sure and all was well for the rest of the day..
A note on the causes I've read, likely you have seen these as well but it's worth mentioning.
I read that they used a type of grease in the lens that gets dried up, causes the motor to "load" unnecessarily against the resistance the dried grease offers, this strain on the motor will ask more of the capacitor(s) and will attempt to overcome the resistance eventually leading to the actual motor failing.
The capacitor thing is another can of worms that not many people have heard of.
The story goes: A design for a series of efficient capacitors was "stolen" by a foreign country that has since taken over the market in electronics. You know who...
What I have heard in the electronics industry is that the formula was stolen but was incomplete..
Millions of capacitors were made with this botched formula, they were then used in all electronics across the planet including Japan.
Every kind of device got them for a period of almost 20 yrs, they are poorly made and they often burst. I have changed many of these myself, the types of devices I've seen them in have been top shelf Japanese made pc mother boards, all audio equipment made by Korg, Tascam, Lexicon, Motu, the list goes on and on.
There are thousand of threads out there on the stupid capacitors, they made it into everything. I wouldn't be surprised if they were used to save money on the lenses..
A capacitor should bleed itself within 24 hrs usually, but the instant the camera is turned on, the lens is also fired up electronically - this should recharge a good capacitor at the speed of light.
The new capacitors made with graphine, that replace batteries keep their charge for a very long time.
But when the lens pause's as your lens did, I would imagine that the capacitor has begun to leak it's electrolyte and it's capacity has become diminished causing a vague connection to the rest of the electronics including the motor controller or the other mythical grease issue.
In some cases allowing the equipment to warm up will recharge a dying capacitor but it will effect the performance of the lens or device. I have to replace 12 big ones in a Tascam DM-24 digital mixer that needs a half hour to warm up, the first half hour sounds like static or fried speakers. After the warm up it's very usable but those capacitors are bulging and waiting to burst, I don't use the mixer at this point in time...
On a positive note, the lens can be converted to screw drive by hacking the firmware, I read that doing so before the motor dies is best, other wise the lens might need to be taken apart to free up the sticky motor first..I hear they track faster than SDM..
Then they said they switched to a new motor...? Who knows. The capicitor thing I have seen personally many times and know that they were used extensively..Pentax is pretty hush hush about what they actually fix when something goes bad, likely they didn't know about the capacitors until well after the lenses were designed and sold. Not really the sort of thing anybody would want to admit to..
It's an upsetting topic, I love the lens, can't imagine not having it in my kit. I bought mine almost three years ago, even making sure I bought one that was not in the flagged serial number list, the extended warranty I bought gets me another two years. Here's to hoping right along with my camera bodies and whatever else I own that has them in it.. :-/
Good luck with yours. I hope the info was somewhat helpful.
Regards,
Damien
Comment by VividArt posted on Is this the reason why SDM lenses need to be used often and are prone to fail? at 02/08/2016 - 08:25
Hello Maria.
I am upset by this news. I do hope you well, your work on this forum has been some of the most pleasing and satisfying work I have ever seen. You are an inspiration to me and many others I'm sure ! Please take good care and PLEASE come back
Even though the news isn't good, thank you for posting it and letting us all know.
You are a valued member of this community, we are all waiting in the hopes of a speedy recovery.
God Bless and kind regards,
Damien
I am upset by this news. I do hope you well, your work on this forum has been some of the most pleasing and satisfying work I have ever seen. You are an inspiration to me and many others I'm sure ! Please take good care and PLEASE come back
Even though the news isn't good, thank you for posting it and letting us all know.
You are a valued member of this community, we are all waiting in the hopes of a speedy recovery.
God Bless and kind regards,
Damien
Comment by VividArt posted on Time out for me at 04/07/2016 - 06:51
Hello folks.
Over here in Canada there seems to be hope. Most of the the bigger shops have Pentax signs, little stands and related marketing items. The selection isn't the greatest, most lenses targeted for entry level consumers, but all the lenses are available. For camera bodies, most of the stores still carry the k52, K3 and K32, a couple of stores have the 645z to play with
The prices seem to be the highest here compared to other countries.
Ask any staff person about Pentax...? One in fifty might know a thing or two.
The used market is getting lean, seems that people are hanging onto their gear..
My two cents
Over here in Canada there seems to be hope. Most of the the bigger shops have Pentax signs, little stands and related marketing items. The selection isn't the greatest, most lenses targeted for entry level consumers, but all the lenses are available. For camera bodies, most of the stores still carry the k52, K3 and K32, a couple of stores have the 645z to play with
The prices seem to be the highest here compared to other countries.
Ask any staff person about Pentax...? One in fifty might know a thing or two.
The used market is getting lean, seems that people are hanging onto their gear..
My two cents
Comment by VividArt posted on Same old story - where is Pentax? at 05/10/2015 - 08:54
Hello folks,
I agree with David. When I use it I also leave a comment. Personally the whole "like" thing is for the FB crowd. I don't always have time to comment as many might, but if I do see a good picture, I "try" to find the time later to go back and thoughtfully comment. I think it's good to hear why someone likes a photo. After all this is a forum of photographers, I don't learn from my mistakes if people don't comment.
Another point, sure there may be folks that don't want to comment because they fear they can't phrase something that sounds "photographic" but that doesn't matter.
Often I see photos that were so well done that I have no idea how to phrase a thoughtful comment, but simply commenting " I like this" is enough, even if I don't know how to describe why I like it. Yes it can be intimidating to read so many thoughtful comments, I may want to leave one but fear that I can't say something original.
One more point, for many of us, time, thought and planning went into a shot, it was an attempt to create a "pro" looking shot, when I see a comment on one of my photos, it tells me that someone looked at it for a little while and were inspired to comment, in a world where "likes" mean so much to so many and hitting the "like" button is so easy, I feel offering a comment is a way of saying - yes I am busy, but wait, this photo caught my attention, if it catches my attention and keeps it, I feel I should make the effort to comment.
For me it's paying respect to the efforts of people that are trying to improve their craft in a world full of camera phones and photos that were taken with automatic mode.
I agree with David. When I use it I also leave a comment. Personally the whole "like" thing is for the FB crowd. I don't always have time to comment as many might, but if I do see a good picture, I "try" to find the time later to go back and thoughtfully comment. I think it's good to hear why someone likes a photo. After all this is a forum of photographers, I don't learn from my mistakes if people don't comment.
Another point, sure there may be folks that don't want to comment because they fear they can't phrase something that sounds "photographic" but that doesn't matter.
Often I see photos that were so well done that I have no idea how to phrase a thoughtful comment, but simply commenting " I like this" is enough, even if I don't know how to describe why I like it. Yes it can be intimidating to read so many thoughtful comments, I may want to leave one but fear that I can't say something original.
One more point, for many of us, time, thought and planning went into a shot, it was an attempt to create a "pro" looking shot, when I see a comment on one of my photos, it tells me that someone looked at it for a little while and were inspired to comment, in a world where "likes" mean so much to so many and hitting the "like" button is so easy, I feel offering a comment is a way of saying - yes I am busy, but wait, this photo caught my attention, if it catches my attention and keeps it, I feel I should make the effort to comment.
For me it's paying respect to the efforts of people that are trying to improve their craft in a world full of camera phones and photos that were taken with automatic mode.
Hello folks,
My two cents. I have the K5II, it's a great camera, the sharpest body I have tried to date.
I picked the K5ii because I was having issues with two different k5's, the new version seemed to have addressed the issues that plagued the first version. It hasn't let me down once, 80k shots - no issues.
I did buy a K3 last year but after reading about the "crazy mirror sickness" I got freaked out and returned it. I kept waiting for a definitive fix through firmware...
I am currently saving up for the K3ii in the hopes that the second gen has had it's bugs worked out.
I don't use the flash very often, the astrotracer is something I have wanted to buy for a while, I imagine their implementation of it in a camera body along with improved SR might make the astro photography experience better, the people that used the first version of the 0-gps1 had mixed reviews of its design and effectiveness. In theory the astrotracer "in camera" might get more attention from the engineers and we may end up with a much improved version as it would be possible to update it through firmware. The improved SR might have been implemented as a method of improving the functionality of the astrotracer. I hope.
The pixel shift feature is quite interesting. I wouldn't mind fiddling with that.
My main reason for considering this camera is the belief that version 2.0 of anything is usually better than version 1.0, it is my hope that the mirror issues are resolved.
My two cents. I have the K5II, it's a great camera, the sharpest body I have tried to date.
I picked the K5ii because I was having issues with two different k5's, the new version seemed to have addressed the issues that plagued the first version. It hasn't let me down once, 80k shots - no issues.
I did buy a K3 last year but after reading about the "crazy mirror sickness" I got freaked out and returned it. I kept waiting for a definitive fix through firmware...
I am currently saving up for the K3ii in the hopes that the second gen has had it's bugs worked out.
I don't use the flash very often, the astrotracer is something I have wanted to buy for a while, I imagine their implementation of it in a camera body along with improved SR might make the astro photography experience better, the people that used the first version of the 0-gps1 had mixed reviews of its design and effectiveness. In theory the astrotracer "in camera" might get more attention from the engineers and we may end up with a much improved version as it would be possible to update it through firmware. The improved SR might have been implemented as a method of improving the functionality of the astrotracer. I hope.
The pixel shift feature is quite interesting. I wouldn't mind fiddling with that.
My main reason for considering this camera is the belief that version 2.0 of anything is usually better than version 1.0, it is my hope that the mirror issues are resolved.
Comment by VividArt posted on K-3 or K-3 II? at 07/07/2015 - 18:52
The main reason I don't try is that I don't believe everything I read. I don't want to risk frying a perfectly functional lens. Seems like it might be safe with the tape, but not about to take a gamble on spotty stuff I read on the interweb. Looking for expert opinions. Last poster has done more research than I have, maybe that is the only option. I had read from a couple of sources that the tape works, but again - the web...
Thanks,
JMD.
Thanks,
JMD.
Comment by VividArt posted on SDM hack question at 04/02/2015 - 21:25
Hello,
I am not an expert. Hacking the firm ware I believe is intended to completely disable the motor. I want an easier option, less permanent option.
I was hoping to hear from those who have actually tried covering the contacts and the camera recognize the lens. I like trying stuff, but I don't fly blind. An experience or two from others that have tried it would make me more comfortable. I guess the main reason I am not trying it is that I am not sure if those two contacts actually communicate info about the lens as well. Like maybe what position the motor is in...I am not sure.
Thanks,
JMD
I am not an expert. Hacking the firm ware I believe is intended to completely disable the motor. I want an easier option, less permanent option.
I was hoping to hear from those who have actually tried covering the contacts and the camera recognize the lens. I like trying stuff, but I don't fly blind. An experience or two from others that have tried it would make me more comfortable. I guess the main reason I am not trying it is that I am not sure if those two contacts actually communicate info about the lens as well. Like maybe what position the motor is in...I am not sure.
Thanks,
JMD
Comment by VividArt posted on SDM hack question at 04/02/2015 - 20:58
Hello Folks,
The over-saturation was present in every single shot. Yes I could adjust the camera accordingly, to dumb it down a bit, but this is the issue. I don't want to create a special "user" location so to speak, for an odd lens.
What I want from a lens is to simply put it on the camera, point it at a subject and get something accurate.
What I was hoping from you all was to confirm that indeed you have seen quality variants. But it seems that maybe you folks haven't...that's good for you, it seems that maybe pentax sends different batches of stuff to different markets.
What I described was my experience with these two lenses, especially the 50mm, the Leading Pentax pro here at my favorite store stood with me as we shot random things in the store and he also confirmed that the lens was behaving strangely. We stood there together going over the camera, he used the same model (k5) as a wedding photographer, knew the camera as well as I did. Nothing changed the behavior of the lens, this became a great topic of discussion with the staff there.
Then he gave me my second copy with many apologies, agreeing to accept the return if I found the second copy to be acting strangely also. I did, but ended up keeping it past the two week deadline, I was too busy to return it on time. So I was stuck with it.
Same story with the 100 wr, different camera store, but I reproduced the problem in front of that guy and he also agreed that it wasn't the camera or me...and accepted the return.
As I mentioned in an earlier post, we get here in Canada - bad copies of lenses and camera bodies.
I agree with all of you about how unlikely this is, but I feel quite satisfied that I did all the requisite testing to eliminate all other possible reasons. The firmware is one possibility, the other most likely reason is the quality of the lens, especially here.
I don't know what else to say, I compared two copies of the 50, one copy of the 100wr to my other gear and to other gear in each camera store. The end of this story is unfortunate - neither store with their experts could understand the cause, but when a different lens was put on the camera right in the stores, why the different results...?
The why, nobody could explain. Thus my question to this forum.
Here in Vancouver I know two pentax experts, one is a Russian guy who runs the biggest store here (Broadway Camera), He and I have had many discussion about this and he has also seen variants that didn't perform correctly. He has had to ship back batches of stuff to pentax that were sub par. This is something that pentax would require significant proof to even consider accepting the returns, but he did, supplied his data and pentax accepted the returns. Although begrudgingly as he informed me.
This store doesn't just sell Pentax, they sell Leica, hasselblad, the nikon and canon lines, along with sony, with those brands there are also huge discrepancies, canon and nikon have their own QA issues.
All I'm saying here: I have seen variants with two lenses, color rendition being the primary reason I decide to not keep a lens, I am not a lab guy that will spend hours and days scientifically discerning the differences between lenses, but the Russian guy here is, also when he lived in Russia. For me to even be able to return a lens for this reason, the camera store requires proof that the lens is faulty. I did this to their satisfaction, what else can I say?
I do appreciate everyone taking the time to offer their opinion; I apologize if I came off defensive or in another way that may have offended anyone. I really do appreciate the time any member has taken. The hard part for me is that I have been through all of this well before I ever decided to post the question, I had to prove to the store owners that the lens was sub par. It was a long, arduous emotionally exhausting process - I really don't want to begin this process of examining all other possibilities again through this forum.
My question was straightforward - Has anyone experienced color discrepancies with these two lenses?
It appears not, and that some of you think it not possible. Ok.
I am only prepared to offer my experience, I don't really want to take the time needed to prove this to all of you who don't believe. I appreciate the curiosity and I certainly appreciate those among you that want to solve the mystery. I just don't have the spare time to engage this way, I was able to satisfy the camera store guy and I feel like I did my due diligence with my own testing.
As I said, I will try to look for the photos I took with these lenses and the comparative shots I took, hopefully I can find them as I would like to show you guys. I have been with pentax for a couple of decades, when they moved their factory the issues began. It upsets me that there doesn't appear to be the same devotion to absolute quality as there once was with pentax. I read that Hoya nearly put pentax out of business, the new owners seem to be trying very hard to bring the brand back to the spec they were once so admired for, but unfortunately here in Canada, pentax has lost a lot of it's older customers. Currently most stores don't even sell the brand anymore as we did experience enough of the occasionally reported issues found on this and the american forum, that most of the stores don't want to sell the brand anymore. It's sad but true. This link is a bit old, but it does illustrate some interesting market differences. http://ricehigh.blogspot.com/2006/12/where-are-pentax-dslrs-and-lenses-made.html
Also for some reason we see brand new versions of most of the newer lenses on the used market that are either old stock? Or still made in Japan...? I hear rumors that they still make small quantities of the best stuff for the Japan only market.
We use a site called Craigslist, if anyone is interested they can peruse the photography section and see these MIJ lenses, they sell for twice the normal price of the lenses made in Vietnam or the Philippines..
I was just offering my experience, don't want to offend anyone or make statements that people don't agree with. It seems I have, I am sorry to upset anyone.
Warm regards to all of you,
JMD
The over-saturation was present in every single shot. Yes I could adjust the camera accordingly, to dumb it down a bit, but this is the issue. I don't want to create a special "user" location so to speak, for an odd lens.
What I want from a lens is to simply put it on the camera, point it at a subject and get something accurate.
What I was hoping from you all was to confirm that indeed you have seen quality variants. But it seems that maybe you folks haven't...that's good for you, it seems that maybe pentax sends different batches of stuff to different markets.
What I described was my experience with these two lenses, especially the 50mm, the Leading Pentax pro here at my favorite store stood with me as we shot random things in the store and he also confirmed that the lens was behaving strangely. We stood there together going over the camera, he used the same model (k5) as a wedding photographer, knew the camera as well as I did. Nothing changed the behavior of the lens, this became a great topic of discussion with the staff there.
Then he gave me my second copy with many apologies, agreeing to accept the return if I found the second copy to be acting strangely also. I did, but ended up keeping it past the two week deadline, I was too busy to return it on time. So I was stuck with it.
Same story with the 100 wr, different camera store, but I reproduced the problem in front of that guy and he also agreed that it wasn't the camera or me...and accepted the return.
As I mentioned in an earlier post, we get here in Canada - bad copies of lenses and camera bodies.
I agree with all of you about how unlikely this is, but I feel quite satisfied that I did all the requisite testing to eliminate all other possible reasons. The firmware is one possibility, the other most likely reason is the quality of the lens, especially here.
I don't know what else to say, I compared two copies of the 50, one copy of the 100wr to my other gear and to other gear in each camera store. The end of this story is unfortunate - neither store with their experts could understand the cause, but when a different lens was put on the camera right in the stores, why the different results...?
The why, nobody could explain. Thus my question to this forum.
Here in Vancouver I know two pentax experts, one is a Russian guy who runs the biggest store here (Broadway Camera), He and I have had many discussion about this and he has also seen variants that didn't perform correctly. He has had to ship back batches of stuff to pentax that were sub par. This is something that pentax would require significant proof to even consider accepting the returns, but he did, supplied his data and pentax accepted the returns. Although begrudgingly as he informed me.
This store doesn't just sell Pentax, they sell Leica, hasselblad, the nikon and canon lines, along with sony, with those brands there are also huge discrepancies, canon and nikon have their own QA issues.
All I'm saying here: I have seen variants with two lenses, color rendition being the primary reason I decide to not keep a lens, I am not a lab guy that will spend hours and days scientifically discerning the differences between lenses, but the Russian guy here is, also when he lived in Russia. For me to even be able to return a lens for this reason, the camera store requires proof that the lens is faulty. I did this to their satisfaction, what else can I say?
I do appreciate everyone taking the time to offer their opinion; I apologize if I came off defensive or in another way that may have offended anyone. I really do appreciate the time any member has taken. The hard part for me is that I have been through all of this well before I ever decided to post the question, I had to prove to the store owners that the lens was sub par. It was a long, arduous emotionally exhausting process - I really don't want to begin this process of examining all other possibilities again through this forum.
My question was straightforward - Has anyone experienced color discrepancies with these two lenses?
It appears not, and that some of you think it not possible. Ok.
I am only prepared to offer my experience, I don't really want to take the time needed to prove this to all of you who don't believe. I appreciate the curiosity and I certainly appreciate those among you that want to solve the mystery. I just don't have the spare time to engage this way, I was able to satisfy the camera store guy and I feel like I did my due diligence with my own testing.
As I said, I will try to look for the photos I took with these lenses and the comparative shots I took, hopefully I can find them as I would like to show you guys. I have been with pentax for a couple of decades, when they moved their factory the issues began. It upsets me that there doesn't appear to be the same devotion to absolute quality as there once was with pentax. I read that Hoya nearly put pentax out of business, the new owners seem to be trying very hard to bring the brand back to the spec they were once so admired for, but unfortunately here in Canada, pentax has lost a lot of it's older customers. Currently most stores don't even sell the brand anymore as we did experience enough of the occasionally reported issues found on this and the american forum, that most of the stores don't want to sell the brand anymore. It's sad but true. This link is a bit old, but it does illustrate some interesting market differences. http://ricehigh.blogspot.com/2006/12/where-are-pentax-dslrs-and-lenses-made.html
Also for some reason we see brand new versions of most of the newer lenses on the used market that are either old stock? Or still made in Japan...? I hear rumors that they still make small quantities of the best stuff for the Japan only market.
We use a site called Craigslist, if anyone is interested they can peruse the photography section and see these MIJ lenses, they sell for twice the normal price of the lenses made in Vietnam or the Philippines..
I was just offering my experience, don't want to offend anyone or make statements that people don't agree with. It seems I have, I am sorry to upset anyone.
Warm regards to all of you,
JMD
Comment by VividArt posted on 50 mm macro 2.8 and 100 mm wr macro over saturating at 03/02/2015 - 22:06
Hello,
Thanks for your reply. I guess I should dare to remove the filter....I know a guy that bought some aftermarket hood that was much bigger for his 50-135.
Yeah the 16-45 was great for that, great lens. The lens that impresses me is the da15 f4 for direct sunlight. Quite an impressive lens in every respect. so many great lenses
Regards,
JMD
Thanks for your reply. I guess I should dare to remove the filter....I know a guy that bought some aftermarket hood that was much bigger for his 50-135.
Yeah the 16-45 was great for that, great lens. The lens that impresses me is the da15 f4 for direct sunlight. Quite an impressive lens in every respect. so many great lenses
Regards,
JMD
Comment by VividArt posted on 50-135 DA* at 03/02/2015 - 10:11
Good topic David.
I have read as much as I could dig up on the subject, I too own the 50-135 and worry..
I had an unexpected shutter click the other day on my K52s. I had just mounted the lens, was half pressing and the mirror flapped as if it was taking a shot..
No shot was taken by the camera.
I pull mine off the shelf every few months and keep using it as has been suggested. My dry fired shot was the only incident that day, I was chasing airplanes at full zoom and it worked fine for the few hundred shots I took that day.
Related? Likely not, but could have been that the lens was not firmly attached. It was, but I re clicked it into place after the failed shot just to be sure and all was well for the rest of the day..
A note on the causes I've read, likely you have seen these as well but it's worth mentioning.
I read that they used a type of grease in the lens that gets dried up, causes the motor to "load" unnecessarily against the resistance the dried grease offers, this strain on the motor will ask more of the capacitor(s) and will attempt to overcome the resistance eventually leading to the actual motor failing. Temperature can be a factor in storing the lens, I would imagine if the lens were stored in a cool place it might make the grease act differently than stored in a warm place. We also need to think about gravity and it's effects on grease over time especially if the lens were stored in a hot place.
The capacitor thing is another can of worms that not many people have heard of.
The story/rumor goes like this:
A design for a series of efficient capacitors was "stolen" by a foreign country that has since taken over the market in electronics. You have a guess who...
Allegedly stolen anyway.
What I have heard in the electronics industry is that the formula was stolen but was incomplete..
Millions of capacitors were made with this botched formula, they were then used in all electronics across the planet including Japan.
Every kind of device got them for a period of almost 20 yrs, they are poorly made and they often burst. I have changed many of these myself, the types of devices I've seen them in top shelf Japanese made pc mother boards, all audio equipment within a certain time frame made by Korg, Tascam, Lexicon, Motu, most manufacturers, the list could go on and on.
There are thousand of threads out there on the stupid capacitors, they made it into everything. I wouldn't be surprised if they were used to save money on the lenses..
Or they were used unknowingly by Pentax.
A capacitor should bleed itself within 24 hrs usually, but the instant the camera is turned on, the lens is also fired up electronically - this should recharge a good capacitor at the speed of light.
The new capacitors made with graphine, that replace batteries keep their charge for a very long time.
But when the lens pause's as your lens did, I would imagine that the capacitor has begun to leak it's electrolyte and it's capacitance has become diminished causing a vague connection to the rest of the electronics including the motor controller or the other mythical grease issue.. Leaking is the worst case of course, they can fail and remain intact..
In some cases allowing the equipment to warm up will recharge a dying capacitor but it will effect the performance of the lens or device. I have to replace 12 big ones in a Tascam DM-24 digital mixer that needs a half hour to warm up, the first half hour sounds like static or fried speakers. After the warm up it's very usable but those capacitors are bulging and waiting to burst, I don't use the mixer at this point in time...
On a positive note, the lens can be converted to screw drive by hacking the firmware, I read that doing so before the motor dies is best, other wise the lens might need to be taken apart to free up the sticky motor first..I hear they track faster than SDM..
Then they said they switched to a new motor...? Who knows. The capacitor thing I have seen personally many times and know that they were used extensively..Pentax is pretty hush hush about what they actually fix when something goes bad, likely they didn't know about the capacitors until well after the lenses were designed and sold. Not really the sort of thing anybody would want to admit to.. with Pentax's commitment to quality then finding out they had inadvertently chosen a bad supplier...it's a bum deal for both parties. It would be nice if Pentax just gave us the adapted firmware. It would be a nice way to make up for the expensive lens failing so soon. It would put a lot of people at ease I think. I feel like each shot it takes might be it's last..
If they had just stayed in Japan!
It's an upsetting topic, I love the lens, can't imagine not having it in my kit. I bought mine almost three years ago, even making sure I bought one that was not in the flagged serial number list, the extended warranty I bought gets me another two years. Here's to hoping right along with my camera bodies and whatever else I own that has them in it.. :-/
Good luck with yours. I hope the info was somewhat helpful.
Regards,
Damien