[C_Jones]

Hi,

I just got a new K-5 yesterday. This is my second one. I wanted to have one specifically for landscape and one for telephoto to avoid changing lenses in the field and avoid the dust/dirt factor. I tested the new K-5 today. On one or two of the first shots I took there was a small spot in the image on the lower right. It is hardly noticeable, but if someone is looking for imperfection they can see it. I took that picture and some others. On most of the pictures the spot does not even show, but I noticed on a few it does. After I noticed that spot on the first set of test shots, I took my rocket blower and blew off the front and back ends of my Sigma 150-500 lens. I then went out and took numbers of shots of the sky at different focal lengths. I brought back the second set of shots, and a large number of those shots (about 70) were spotless. Then I got to these shots that showed similar to the same thing that I had seen in the first set of test shots. Please note the attached images. ImgP0004 is one that has the spot on it. ImgP0005 is one that is a similar type of shot (of the sky), but does not show a spot. This camera is brand new. This is not a major problem, but you probably know how it is when something is not just right or maybe there is something you can do to remedy it, especially on a technical item. I would appreciate any advice on what I should do. I will probably call Pentax customer service tomorrow and ask them. I did use my dust removal already and it is set to activate each time I turn it on. I have only used air (rocket blower) on my lenses prior to this, and have never attempted to clean anything internally on any of my cameras before. As I mentioned, I would appreciate any advice, and thank you ahead of time for any.

Casey

[elliott]

Sensor dust is more visible at smaller apertures, your top shot was at f16, bottom was at f10.

[Adam]

The dust should fall off eventually. If it doesn't, then CRIS will probably be willing to clean your camera under warranty.

[C_Jones]

I was just going to post the aperture factor as Elliott did. I noticed the effect of the aperture revealing the spot in different shots at F16 and not at F10. That would be great if the dust would fall off. I will confide in Pentax customer service tomorrow and ask what I should do if the dust does not fall off. You two told me what needed to know. I have the original warranty (bought the camera brand new on Amazon from Beach Camera) and extended warranty (2 year) so I will do what customer service recommends.

You were both extremely helpful, thank you. Have a good night.

Casey

[Eric Auer]

Had a similar issue on my K-5 IIs, Lifted up the mirror and it was visible on the sensor. Light blow with a Giotto Rocket took care of it.

[oxidized]

This is likely just sensor dust. I had that on my brand new K-7 also. If you blow at it sometimes it falls off sometimes it doesnt. If you are persistent enough it could fall or just change position. At some point I just gave up and learned to live with it. Every once in a while it will show up on a landscape pic and I will just photoshop it out :/

[C_Jones]

Corto-PA, I have a Giotto Rocket also. I have always used it on my lenses only. I am not too familiar with using it on a sensor but have seen others comment about using it as you mentioned. Though I have hardly ever changed lenses on my cameras, I am more used to just getting the lens mounted and sealing the camera that way than keeping it open and even looking at the sensor, let alone using the Rocket to blow away dust. I suppose you would just blow the rocket air on the flat sensor and look under a light while you are doing it to look for specks of dust. I am not familiar with how vulnerable the sensor is and have not ever attempted "Rocketing" air on one.

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Last edited by C_Jones; 11-11-2012 at 09:25 PM. Reason: small addition

[C_Jones]

Oxidized, I am in a very similar situation as you stated. I was thinking almost the same thing as in living with it, since the spot did not show all of the time. On the other hand I want to be as meticulous as possible. The reason I bought this camera was to be able to not have to switch lenses and avoid dust. I have decided to return this camera, and look at the current prices on another one (K-5). As I stated I already have one K-5, and I just love it. I don't mean to exaggerate, but it is like photography took another step in a very nice way when Pentax made this camera. Thanks for your reply.

[oxidized]

The burden of perfection is a heavy one indeed.

[C_Jones]

I am going to take the careful route of returning it this time. If I get another one that has a similar problem, I am going to confide in Pentax customer service on the matter and take their advice on how to resolve it directly. If they tell me directly to attempt to clean it myself I will. The combination of customer service and the forum keep me well informed. As I mentioned before, my aim is to avoid the dust in the first place. I appreciate all of your help. The shipping carrier is supposed to be here today to pick up my return. I want to mention with regard to advice on cleaning the sensor myself, it sounds like exactly the thing to do and I really respect the technical advice I received, but I am just going to try to get a body that does not require the cleaning in the first place this time.

Thanks

[elliott]

You'll still get dust eventually, it is nearly unavoidable, especially with that giant air pump of a Sigma.

[lister6520]

I am going to take the careful route of returning it this time. If I get another one that has a similar problem, I am going to confide in Pentax customer service on the matter and take their advice on how to resolve it directly. If they tell me directly to attempt to clean it myself I will. The combination of customer service and the forum keep me well informed. As I mentioned before, my aim is to avoid the dust in the first place. I appreciate all of your help. The shipping carrier is supposed to be here today to pick up my return. I want to mention with regard to advice on cleaning the sensor myself, it sounds like exactly the thing to do and I really respect the technical advice I received, but I am just going to try to get a body that does not require the cleaning in the first place this time.

Thanks

It is absolutely normal to get such spots from time to time. With an SLR it is something you have to learn to live with unless you live in a cleanroom. The sensor will need cleaning every now and then. Most often the dust can be blown off but sometimes it will need some more effort.

If you take the camera for cleaning do not be too surprised if it comes back with a more visible dot. No matter how well they do the job no one can guarantee that another speck of dust won;t settle on the sensor by the time the camera gets back to you.

I think you should just try to blow it off and if it doesn;t come of just leave it there. When you collect some more spots that cannot be blown off maybe that would be the time to take it for cleaning.

Always keep in mind that the narrower the aperture the more visible the dust will be. The spot you have seems to show only at F16 and narrowe, which normally you wouldn't want to use anyway because your sharpness will be degraded by diffraction.

[C_Jones]

Thank you lister6520 and all of you others for your advice/information. It helps me understand the factors involved and what can be done. Have a nice Thanksgiving.

[C_Jones]

Hi,

I received my replacement K-5 two days ago, and took it out to take some pictures today. I am happy with the results, and now have two K-5s. One I use for landscape, the other for birding/wildlife, and I do not have to switch lenses in the field. I did use my Giotto blower on my lens before I attached it, and inspected it with a penlight. So, my situation is a good one now. Thank you everyone. Happy Holidays!!

Casey

[tabl10s]

Doesn't anyone here use the Sensor cleaning function?