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Forum: Pentax K-3 & K-3 II
05-21-2018, 12:20 PM
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This problem also occurs in Pentax k-1.
However I do not want to lift the mirror because I'm afraid that I will damage something but the symptoms are the same.
AF inconsistance is most visible with the DFA * 70-200 lens. The problem appears on distances of somewhere 10 meters and more. At first photo - front focus by half the distance, the next shot - back focus by 20 meters, next one - front focus by 1 meter, and another one almost accurate and so on. One photo of ten is spot on. I have checked two copies of DFA * 70-200 on my camera and both my lens and my friends one are completely unpredictable on my Pentax k-1. While the same friend's lens with his k-3 and other cameraz is always perfectly accurate.
I know that my cockeyed k-1 is not the only one.
This guy has exactly the same problem with his Pentax k-1 and DFA* 70-200.
Pawe? Kot | Facebook |
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Forum: Pentax SLR Lens Discussion
05-14-2018, 10:37 PM
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No he is not. This is the lens that I received in exchange for the previous damaged copy and I got it from the Ricoh imaging marketing department.
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Forum: Pentax SLR Lens Discussion
05-14-2018, 02:09 PM
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In general the main thing I wanted them to check was misalignment. The technician said that the lens is not telecentric, but he did not write it into the expertise, because there is no need to enter it -
he explained. I had to argue for half an hour to have it on paper. When he kindly agreed to include a mention in the documents I asked him to take a picture and look at how huge the defect is, but he said he is about to finish his work, he turned around and went away. And the receptionist said: "the expertise is completed, bye."
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Forum: Pentax SLR Lens Discussion
05-14-2018, 01:19 PM
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This is an expertise of the official Pentax service "Opto-technika" in Poland. Before I tried to get an email address to Pentax in Japan from the Ricoh-aftersales in France (they know the matter too), but they refused.
Awscreo, yes this is the new replacement of the DFA 70-200 which was broken too. I can not deal with them for over a year. My K-1 is broken too. So was my previous 5 examples k-5 and k-5II.
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Forum: Pentax SLR Lens Discussion
05-14-2018, 01:10 PM
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Today I received the Pentax DFA* 70-200 from the official Pentax service. I asked them for an expert opinion. Here's what they wrote:
" Summary: The lens is mechanically and optically in very good condition (...) the reduction of resolution on the left side of the frame does not matter in use ( at 70mm focal length, while maintaining the standard lens angle of view) ... no chromatic or spherical aberrations were found " .
I do not know what to think about it. Here's what the lens on the right side and left side looks like in real.
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Forum: Pentax SLR Lens Discussion
04-06-2018, 04:26 AM
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I checked in this respect my k-1 with a friends dfa* 70-200 lens and three of my other lenses and picture was correct. I informed Ricoh about it.
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Forum: Pentax SLR Lens Discussion
04-05-2018, 05:18 PM
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I wanted to mail directly to the headquarters in Japan and describe the problem, but I could not find an e-mail address anywhere on the Internet. So I asked the Ricoh aftersales department in France for an e-mail address to Japan. Unfortunately, they refused to give me the address, explaining that it is pointless, because my email will be automatically redirected to France.
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Forum: Pentax SLR Lens Discussion
04-05-2018, 03:11 AM
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Thanks Reed that's right. The first two photos of street light were taken by rotating the camera within the tripod collar. Manual focus was set in the first picture and than was locked to make the second one.
The next 4 photos of street lampshades were made traditionally - using the linked method. The focus has been set manually on object placed in the corner at first shot (the sharpest one).
How to Check Your Lens for Decentering - Articles and Tips | PentaxForums.com
And when it comes to the inconsistant AF, this is another fault and it seems to me that it is a K-1 defect, because both my copy and my friends 70-200 are completely unpredictable on K-1.
While the same friend's lens with his k-3 is always perfectly accurate.
Yes, I have the Lens Align. But it is useless in this case, because the problem appears on distances of somewhere 10 meters and more. At first photo - front focus by half the distance, the next one back focus by 20 meters, next front focus by 1 meter, and another one almost accurate and so on. (another colleague has the same problem).
This is not the first defective Pentax camera I bought as a new. Five in a row of k-5 and k-5II cameras were defective. Perhaps this is just a problem for a specific batch of goods intended for the Polish market. A place where 1 euro = $1 = 4 zlotes and people have to save money 3 times longer to buy their ideal equipment.
Additionally, each time there were problems with the complaints because the service did not find any problems. They did not find any malfunction of AF in incandescent light, they did not find any problem with the mirror flop issue, the lack of flat contact pin on the bayonet mount (all ball) was not a problem too so wasn't the jamming button nor randomly displayed stamps on the upper display when the camera was turned off.
Maybe that's why the children in the photo school here have a given essays about "The reasons why you should not buy Pentax".
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Forum: Pentax SLR Lens Discussion
04-04-2018, 05:42 AM
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I had the same problem with a brand new Pentax DFA* 70-200 a year ago. After repair a new problem with autofocus occured. One of ten photos was sharp, two was acceptable and
the other photos had a giant front focus and a back focus - for a change.
After more than two months in the Germany service and losing my documentation of the complaint, I received a new copy replacement.
The new copy is decentered too. HUGE decentered. And except that again more than 70% of photos are completely out of focus.
I have mailed service in France again and I sent a lot of examples. According to this method :How to Check Your Lens for Decentering - Articles and Tips | PentaxForums.com
and I sent single photos too, because decentering is clearly visible without any tests. I also checked if my camera is not crooked, but all other lenses are ok.
Guess what is their answer? That it's hard to see if it is broken so I have to send it back to the service again. Because no worrying chromatic aberrations they can see ...
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Forum: Troubleshooting and Beginner Help
01-14-2018, 12:30 PM
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Shuter speed was 1/90 but I tried different speeds like 4s and I used manual.
Why do you think that this is about screen refreshing?
Do different websites cause different refreshing? Is there any other refresh rate at the top of present page than at the bottom?
And if a reason is the screen refreshing why it affects an area beyond the monitor ?
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Forum: Troubleshooting and Beginner Help
01-14-2018, 08:26 AM
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It turns out that not only Google but web pages that have a light interface from edge to edge.
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Forum: Troubleshooting and Beginner Help
01-13-2018, 12:01 PM
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Adam, This is out of camera jpg, resized in PC only.
GMounk, Please read again my last post above. I have pointed out that the strip overlaps not only the monitor screen but the housing too.
Ex Finn. I meant that the screen flashes and refreshes but the frame around the display does not. It is made from black plastic. Despite this, the purple strip covers it.
Rondec, Thank you for the idea. Nice photo.
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Forum: Troubleshooting and Beginner Help
01-12-2018, 02:35 AM
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Thanks for the reply.
Adam, pinholecam note that the picture has a barrel distortion and the violet bar have not.
And here, plastic monitor frame. It is fresh all the time :)
I also tried 1/90s.
Ex Finn, this is not the only puzzle with my pixel shift, but first things first.
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Forum: Troubleshooting and Beginner Help
01-11-2018, 06:00 PM
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Hello,
I would like to share some observation. I wanted to check the difference between the pixel shift and the single photo mode with a new lens. Pointed the camera at the monitor and made several photos.
I paste one of them and a crop here because I have no idea what it is.
Few observations.
The violet bar appears at different shutter speeds and different apertures, regardless of the SD card and SD slot.
It appears when I move the focus slightly backward or forward, just enough to make the moire disappear.
The bar disappears hovewer when focus is moved significantly and the picture is vague.
The bar disappears when another website is opened
and is coming back when the Google browser is opened. So I open different websites and Google alternately a dozen times and every time when I take a picture of Google browser, the violet bar appears and in the pictures of other sites the bar disappears. It disappears in pictures of desktop, photos, programs also.
Of course it happens by accident. So is it a fault ?
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Forum: Pentax Forums Giveaways
12-14-2014, 07:32 AM
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Forum: Photographic Technique
12-11-2014, 08:21 AM
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BrianR, yes I have all parts.
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Forum: Photographic Technique
12-11-2014, 05:15 AM
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Question to the users of the autofocus macro lens.
Do you often disable the AF and focus manually?
I wonder whether it makes sense to put up for sale among Pentaxians, my Leica macro apo elmarit 100/2.8 converted to the Pentax K mount using the Leitax.com part. Or should better undo the conversion and ask someone to issue on ebay.
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Forum: Pentax Full Frame
06-07-2014, 02:56 PM
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It was only a month more between the announcement of the Pentax k20d and k-5. Maximum iso of the Pentax k20d is 6400 and maximum of the k-5 is 51200. It is 3EV.
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Forum: Pentax Full Frame
06-07-2014, 10:59 AM
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Nikon d800 went on sale in March 2012 at a price of $ 3000. 36 megapixels, iso 25600 and large dynamic range roughly describe its ability.
Between the announcement of d800 and Photokina 2014 there is more than two and a half years. It can be assumed that if the number of megapixels, DR and price will remain unchanged then iso will increase (and improve) of at least + 1,5 EV.
At least the same parameters must be FF Pentax in the same price.
So Pentax FF: $ 3000, ISO 76800, resolution 7360 x 4912.
And Pentax MF: $ 8500, ISO 76800 + 1,33 EV, resolution 8256 x 6192.
(in terms of iso of course there is little difference between 5.3 microns vs 4.8 microns; but on the other hand also sensor advancement Apr 15 vs Sep 21)
+ fps + size + weight + max shutter speed + built in flash + lens prices...
What parameters and price for FF Pentax could be competitive to canikon and at the same time logical compared to 645Z ?
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