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Forum: Pentax SLR Lens Discussion
08-12-2019, 04:02 AM
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You probably set the focus limiter by accident.
Change the Focus Range setting to "Full".
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Forum: Pentax SLR Lens Discussion
03-03-2019, 06:35 AM
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I feel that honesty should work both ways.
If the OP has taken apart the lens, them he accepted the responsibility of ownership and should not attempt to return it. The best he can hope for will be a small compensation.
---------- Post added 03-03-19 at 10:36 PM ----------
Please see the photos. The last two photos show front part of lens only. Though, admittedly it doesn't look like the Sonnar lens.
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Forum: Pentax SLR Lens Discussion
03-03-2019, 06:30 AM
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Also, how the seller handles claims can be swayed by the attitude shown by the buyer.
Hopefully, the OP didn't accuse the seller of being a "liar" right off the bat. Calling someone a liar implies that that person is dishonest. Most Japanese merchants pride themselves on running an honest business and being accused of lies will undoubtedly make them less inclined to be helpful.
Now, I'm not saying that this particular seller had no bad intentions, I just don't know, but it usually helps to begin any negotiation with politeness.
Diplomacy is the key.
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Forum: Pentax SLR Lens Discussion
03-03-2019, 05:45 AM
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The only problem I see with return or discount is that it appears that you have already attempted to do a self-repair and taken the lens apart.
The seller can claim the damage is due to your actions.
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Forum: Pentax SLR Lens Discussion
02-21-2018, 04:15 PM
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If you don't see a retaining ring, then yes, the element is probably pressed sealed into the plastic or metal barrel. Whilst it is possible to cut away the surrounding material to release the lens (I've done it many times before with success), it's probably not worth the time and effort in this case. The lens in question is relatively inexpensive and you'd be better off buying a good, used copy.
Actually, there is a possibility that the retaining ring is on the inside, not visible from the front. In which case, you'll need to disassemble the front group.
Sorry, I don't think I've worked on this lens before, so I don't know its construction details.
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Forum: Pentax SLR Lens Discussion
02-19-2018, 07:14 AM
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KENKO Pz-AF UNIPLUS TUBE 25
25mm extension tube with both screw drive AF and SDM AF contacts, as well as auto exposure.
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Forum: Pentax SLR Lens Discussion
02-18-2018, 11:07 PM
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1.) Remove the rubber grip.
2.) You'll find the adjustment screws as circled in the photo attached. There'll be another set on the other side.
3.) Loosen all four screws.
4.) Rotate the section marked "A" in photo either clockwise or anti-clockwise as required.
5.) Re-tighten screws.
6.) Re-fit rubber grip.
7.) Done!
---------- Post added 02-19-18 at 03:12 PM ----------
Actually, there are set of screw holes underneath and you'll probably have to remove the screw instead of just loosening it to allow movement.
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Forum: Pentax SLR Lens Discussion
03-11-2017, 06:19 PM
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Yes, the grip just peels off. I've worked on at least 20 or so of these lenses so i'm quite sure.
Use a thin piece of wood like an ice cream/popsicle stick and work around the lens gently.
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Forum: Pentax SLR Lens Discussion
03-11-2017, 03:44 PM
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On the A50/1.4, the trim ring or the ring with the lettering on it is not threaded.
You need to remove the rubber focus grip first and then you will see three holes. You poke a screwdriver in to those holes to release a catch. Be careful not to use too much force as you may break the plastic clips.
You then loosen the grub screw on the filter mounting ring and unscrew that to get full access.
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Forum: Pentax SLR Lens Discussion
02-07-2017, 07:22 PM
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It seems both "repairers" took the easy way out and cleaned just the blades, instead of doing a proper CLA.
They should have disassembled the lens to clean not only the aperture assembly but also clean and re-lube the focus helicoid.
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Forum: Pentax SLR Lens Discussion
01-26-2017, 08:49 PM
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Technically, you're correct regarding replacement of the ball bearing to restore the click between f-stops. However, the A position of the aperture ring is controlled by a separate push button, so you shouldn't need the ball bearing for that.
If you do decide to disassemble the lens, be careful of the tiny contact pins and springs that may jump out when you remove the mounting plate.
Also, the screwdriver required for removing the mounting plate screws is JIS +0.
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Forum: Pentax KP
01-25-2017, 11:44 PM
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Forum: Pentax KP
01-25-2017, 06:57 PM
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Yodobashi Camera has listed the KP with price of 137,700JPY including tax, minus 10% in points, so the net value is 123930JPY or approximately 1095USD at current exchange rate.
More interestingly, they are calling it a "middle class" model, giving more credence to the rumour that "top class" APS-C model is still to come.
Currently, Yodobashi are selling Pentax DSLR's of K-1 and K-70 models only. (KP will be available on Feb. 23) All others are marked as "No longer available".
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Forum: Pentax News and Rumors
01-24-2017, 07:15 AM
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Noticing that IR sensor for remote release is missing, so I guess it will be all done using your smartphone via WiFi. It would be nice if they include an extension in the app to use your smartwatch to trigger the shutter at least.
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Forum: Pentax SLR Lens Discussion
12-19-2016, 09:12 PM
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As the lens is "screw drive" type, you will hear some noise.
Are you moving the focus with the lens mounted on the camera? If so, do you have the camera set to manual focus mode?
The noise you hear should be more of a whirling noise rather than distinctive clicks.
Does the lens work OK in AF mode? If so, I wouldn't worry too much as that indicates the focus mechanism is working without glitches.
If it still concerns you, I suggest you contact the seller immediately and discuss an amicable resolution.
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Forum: Troubleshooting and Beginner Help
12-15-2016, 09:21 PM
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Perhaps Adam can create an FAQ page and a prominent link on the home page.
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Forum: Pentax SLR Lens Discussion
11-07-2016, 05:42 PM
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I generally don't recommend people to disassemble a lens unless they have the appropriate skill and knowledge, but adjusting infinity focus should be easy enough for most.
The M28/3.5 shares the same basic construction principle as M50/1.4 so just follow the instructions for that lens, which are readily available on the web.
Quick guide:
1.) Remove name ring with rubber stopper, etc. You really need to be careful at this step. Using the wrong size stopper can scratch the lens if it has grit and dirt on it. Also, it can be very difficult to remove if someone has used a thread locker previously or the filter attachment ring is out of shape.
2.) Removing the name ring will reveal three screws which when unscrewed will let you remove the filter attachment ring.
3.) Removing the filter attachment ring will reveal further three screws that you loosen to adjust the infinity focus.
The screws involved are JIS +00 standard and use of appropriate screwdriver is recommended.
When everything goes well, it's an easy repair, However, if you come across problem like stubborn screws then this is when your knowledge and skill is required so that you don't end up stripping the head.
Every lens repair comes with risks so proceed at your own decision.
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Forum: Repairs and Warranty Service
11-05-2016, 07:56 AM
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Sorry to hear about your friend's accident.
Hope is great to have, but sometimes you have to face reality.
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Forum: Pentax SLR Lens Discussion
11-04-2016, 09:53 PM
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It sounds as if someone has taken the lens apart before and did not re-assemble it properly.
There are already some articles on assembly/disassembly of this lens.
Just google "pentax a50/2 disassembly". Although a sightly different design, you can get some hints by looking at other 50mm lens as well such as M50/1.4, M50/1.7, etc.
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Forum: Pentax SLR Lens Discussion
11-04-2016, 09:29 PM
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They are marks left behind after condensation has dried.
Just as a glass filled with cold liquid causes condensation on the out side (you see the small droplets of water), a lens can develop them when subjected to sudden change in temperature. If there are any contaminants in the air, the droplets will leave a mark as it dries.
The more solid white marks are vaporized oil or grease.
Another common cause of clouding is aging of glue used to bond paired elements. This lens, however, does not have such group in its optical design so it can be ruled out.
It looks pretty bad but in fact it should clean up fairly well to a point where it will be usable. However, if the marks have been there for a long, long time and the lens has been stored in an inappropriate environment (high heat and humidity) then it's possible that it has caused a permanent damage.
Like I said before, the lens is cheap, so It's only worth cleaning if you can do it yourself.
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Forum: Troubleshooting and Beginner Help
11-04-2016, 09:14 PM
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Dust on sensor does not cause this kind of problem. Dusty sensor causes dark spots to appear. This is definitely an electrical issue.
Don't go cleaning the sensor with swabs and such unless necessary. Although it's fairly easy and safe to do, there's always a risk that you will end up scratching the surface ESPECIALLY if you live in an environment where there are gravel dust which contains quartz (harder than glass).
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Forum: Pentax SLR Lens Discussion
11-04-2016, 04:21 AM
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Without having a first hand look at the lens, it's difficult to give accurate diagnosis, but I suspect the "fingerprint" you're looking at is what I call clouding or haze.
The clouding will cause loss of contrast and hence won't have the proper colour rendition.
My suggestion is to sell this lens, with proper disclosure about the clouding, and get yourself another good copy. These lenses are easy to find and not expensive. Unless you know how to open up a zoom lens and clean the internal elements yourself, it's not worth the money to have it cleaned professionally.
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Forum: Pentax SLR Lens Discussion
11-03-2016, 07:50 PM
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It sounds like the lens has some clouding or fungus issues.
Hold the lens with bright light source (open window, etc.) behind it and look through the lens. Due to the small diameter of some of the internal elements, it may not be easily discernible but look carefully. You can also use a flashlight, but if you use a super bright LED type, then be careful that you don't blind yourself (temporary). Note that any LIGHT clouding you see with LED flashlight test will have very little effect under most normal shooting conditions.
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Forum: Troubleshooting and Beginner Help
11-02-2016, 06:56 AM
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As others have suggested, I would have suspected the SD card too.
If you don't see the problem when photo is previewed on the camera's monitor, then it would have to be the SD card. I believe the preview images come from the camera's internal buffer so if the photo is OK there, then it would indicate that the sensor is OK.
If the above is true, and since you've already tried different SD cards, try cleaning the SD card slot. Start with an hand-squeeze type air blower and if that doesn't fix it, try a can of compressed air (the type that does not leak even when the can is inverted) but be careful you don't jam the nozzle in too far. Lastly, get a can of electrical contact cleaner and spray it on the SD card contacts, insert and remove several times. DO NOT SPRAY into the camera directly. Although it should be safe, I don't recommend it.
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Forum: Pentax SLR Lens Discussion
10-31-2016, 12:30 AM
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If it wasn't there when you packed it, and no one has touched it since then, and now there's some marks inside the lens, definitely suggests that it's a fungus.
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