[kyteflyer]

A single blot vertically centred and horizontally in the left 1/3 of the screen. At first, I thought it was my computer screen and tried to clean it off. Didn't work.

I then thought, oh its one of the older lenses and I've been careless about cleaning. Except that its on all shots I did tonight in which there was a light coloured sky. I used 3 different lenses, one of which was my brand new 15mm (as in brand new received 3 hours before I went out).

My heart is sinking... and I'm hoping that in the light of day (or on closer looking) it will turn out to be something that was just in *that* part of the sky. I'll take some wall pix also. Not feeling too hopeful.

Right now I am going away to take some deep breaths and chill out. Tomorrow is another day.


Taken with DA15 (cropped to the blot, of course)


Taken with DA35 f/2.8 and pointing in the opposite direction to the others


Taken with Tamron 70-300 at 70mm

Not sure what if anything I'll do about this. I am often out shooting sunrises but more frequently seek those with lots of clouds, they work better. The stain, such as it is, is visible more markedly in skies which become darker eg as the sun goes down... and not at all in extremely light skies.



and



All shots are 100% crops, of course.

Sighhh. Last shot. Small amt cropping, plus resize for display here. The blot is very noticeable.



Now I really am going for the night.

---

Last edited by kyteflyer; 01-25-2011 at 04:29 AM. Reason: adding pix

[twitch]

Buy rocket blower. Use. Problem gone.

[kyteflyer]

Buy rocket blower. Use. Problem gone.

A bit flippant methinks.

[twitch]

It's clearly dust, no need to stress.

[kyteflyer]

It's clearly dust, no need to stress.

Why doesn't it show up when I tell the camera to show me the dust?

Also,whats the rocket blower, I've seen it referred to in other posts.

[ionutmar]

like that
Giottos Rocket Air Blower Review

[theperception2008]

Hi kyte flyer,

That looks like dust to me too. It happens unfortunately. I went through an entire summer vacation taking over 1k photos not realizing that I had dust spots on my sensor. Now that is a PP nightmare! Use the rocket blower often and hold the camera down (the mount towards the ground) as this will let the dust fall out and not stay in the mirror box. the small dust specs are usually taken care of by the built in dust cleaner on the sensor, but the big particles are the ones that stick and need to be "blown" out.

To determine if you have oil stains, shoot a picture of a well lit uniform wall at aperture of f/22 and then if you see small little spots with a white dot in the center. Those then would be considered oil stains.

I hope that helps!

[Hypocorism]

Why doesn't it show up when I tell the camera to show me the dust?

Also,whats the rocket blower, I've seen it referred to in other posts.

Welcome to the K-r Klub. So what's so different with yours?

Fair Question: The main reason why the inbuilt Dust Removal doesn't show or remove it, is because that function's only a crude snapshot, then a vibratory action thing that can only reveal, and or subsequently move the most basic & very loose magnetic-attracted surface dust, not any real "sticky poo".
It's like 'shaking' all the dusty objects in your house, instead of wiping, washing, vacuuming, etc., and I bet you already know how bloody useless that method would be for real cleaning!

Rocket Blower is one of those hand held bulb-puffer air squirty things, probably the more famous brand is Giotto like this; Giottos Rocket Air Blower - Large
Definitely worth owning one, essential with cameras (and PCs too) really, but very unlikely to solve this issue of yours I reckon.

Yes I'd agree with the other respondents that it's almost 100% certain to be crud/dirt/filth/you_name_it, courtesy gift from manufacture -- and not really a big drama.

Anyway, smart move that you actually made an effort to inspect that critical component of your expensive toy, most people don't (sadly...) but I wouldn't be alarmed at this stage. In fact I recommend you use it for the experience to learn to maintain your valuable investment. It's worth it, and fun too to be self-reliant, IMhO.

Wanna boring read about my new K-r (and K-x)?
Dirty Sensor #1 - brand new Pentax K-r [@ f/40] | Flickr - Photo Sharing!

Fwiw: I've since located similar less expensive cleaning tools and will probably buy that alternate brand for my own needs next time. (eg. DCW charged me AUD65 for the O-ICK1, although it should last a long time in normal care and use.)

Fwiw2: Got mine from stoopid JBHiFi and it registered the obligatory standard #2 Shutter Counts on its 1st actuation as part of my life (so it wasn't a pre-loved/recycled/musical-chairs one by any means.)

NP. With a little TLC, it's easy to enjoy your K-r even more. (and get 100% crisp pix too! )

.R.

[kyteflyer]

... I went through an entire summer vacation taking over 1k photos not realizing that I had dust spots on my sensor. Now that is a PP nightmare!

OMG! I would be REALLY ticked off if that were me!!!

Anyway, smart move that you actually made an effort to inspect that critical component of your expensive toy, most people don't (sadly...) but I wouldn't be alarmed at this stage. In fact I recommend you use it for the experience to learn to maintain your valuable investment. It's worth it, and fun too to be self-reliant, IMhO.

Actually I'd like to claim obsessive checking of stuff but I didn't. These blots on my landscape were really obvious as soon as I looked at them.

I was on the brink of packing it up and taking it back to JB. I'd rather have a clean sensor though. I do have a blower, but it has a brush and I'm not putting that inside my camera. I'll take a look at all the options (and see what, if anything, can be got around town rather than having to wait for shipping)

Thanks heaps for your various links and suggestions, all of you

[kyteflyer]

Followed instructions here and got a whole mess of dirt and crud showing up... but nothing in the exact location of that in the shown shots. Maybe its moved.



at least some of this is my grotty computer screen but...

[edit] I notice everywhere its claimed that the spots are most likely to show on light backgrounds. In mine, "normal" sky shots don't show it (which is probably why I hadn't seen it until last evening's shots) and the darker the sky became, as the sun dipped further below the horizon, the darker the spots appeared. Of course there's a point that spot and background would merge, but thats how it was. There are no spots on earlier shots with a light blue sky. Weird

[Hypocorism]

Followed instructions here and got a whole mess of dirt and crud showing up... but nothing in the exact location of that in the shown shots. Maybe its moved.

at least some of this is my grotty computer screen but...

[edit] I notice everywhere its claimed that the spots are most likely to show on light backgrounds. In mine, "normal" sky shots don't show it (which is probably why I hadn't seen it until last evening's shots) and the darker the sky became, as the sun dipped further below the horizon, the darker the spots appeared. Of course there's a point that spot and background would merge, but thats how it was. There are no spots on earlier shots with a light blue sky. Weird

Hah. A PC screen is a useless subject for this (quite technically inept to advise that actually). Use a large sheet of white/light paper instead, or, one of your smooth painted walls, else the sky if it's nice and clear up there today.
Those big smooth sheets of flat thin craft cardboard from newsagents/Kmart etc., are good and can serve as a flash or sunlight reflector later too.

Forget your old already taken photos. Do this seriously as an independent, controlled test, so that you can properly define the problem's extent for safe, sensible and complete correcting.

I suspect you are not stopping the lens right down either, though all your sample pics posted here have their EXIF butchered so provide no useful info for fair analysis.

Yours definitely does look very dirty though so I'd highly recommend the full Monty systematic approach.
Hint: those very large grey blotches that you see in your previous posted samples will mostly dissipate into increasingly smaller dark black objects (as per my sky of Flickr) when taken stopped right down to say f/22 and beyond. (Your 18-55 will go to f/40 so is great option for this job)

Keep at it, you'll get there. Result will be well worth the trouble but please don't try and clean it with any cheap silly rubbish method or product (or read more silly websites).

.R.

[kyteflyer]

Hah. A PC screen is a useless subject or this. Use a large sheet of white/light paper, or, one of your smooth painted walls, else the sky if it's nice and clear up there today.

Forget your old already taken photos. Do this seriously as an independent, controlled test, so that you can properly define the problem's extent for safe, sensible and complete correcting.

I suspect you are not stopping the lens right down either, though all your sample pics posted here have their EXIF butchered so provide no useful info for fair analysis.

Yours definitely does look very dirty though so I'd highly recommend the full Monty systematic approach.
Hint: those very large grey blotches that you see in your previous posted samples will mostly dissipate into small dark black objects (as per my sky of Flickr) when taken stopped right down to say f/22 and beyond.

Keep at it, you'll get there. Result will be well worth the trouble but please don't try and clean it with any cheap silly rubbish method or product.

.R.

Thnaks, I will do some testing today, already got the white paper out, I'll blutak it to a wall (my walls arent suitable as is) and also do more sky shots. The last shot was at f/22 (computer screen) but the others were f/4 (first 2) and f/11. so yeah, I'll try more at max and see how it goes.

Not cleaning it with anything until I've established whether I can live with it or not. I've decided to get a good blower anyway (as per your link) but if anything has to be done to the sensor, I'll take it to a technician, its something I would hate to screw up.

[eddie1960]

blower then a cleaning kit both easily done by users
Pentax and visible dust both make good cleaning kits and they last a long time (12 wands with visible dust for $40 locally)
Giotto as said for the blower. Start with the blower but as above i think you have more issues than a blower would deal with. If these 2 methods don't work then you are off to service but in reality the $50 or so dollars you spend on the cleaning stuff is way cheaper than service. just follow the instructions that come with the cleaning kits
(BTW a lot of service techs use visible dust swabs first)

the liquid cleaner techs use is really next to impossible to buy at retail as it is a controlled substance

[kyteflyer]

blower then a cleaning kit both easily done by users
Pentax and visible dust both make good cleaning kits and they last a long time (12 wands with visible dust for $40 locally) ...

Thanks, I didn't realise Pentax made their own, will look into that. The blower is on order even as we speak.

[JeffJS]

It's dust. The computer screen is ok for looking following the sensor cleaning website but the best thing to use is a clear blue or completely overcast sky.

https://www.pentaxforums.com/forums/pentax-dslr-camera-articles/121739-those-...ml#post1259109

This is what a Stain looks like..