Spotty istD images


Link Posted 06/09/2004 - 23:20
I finally decided to go for the *istD just last week. Started shooting with it on Saturday and since have taken about 100 or so images. The latest ones show some greyish/black spots - one in particular. The marks appear regardless of lens changes so I presume the marks must be either imperfections or dirt on the sensor. Any advice on how to sort the problem?


Link Posted 06/09/2004 - 23:33
This sounds like a classic dirty sensor.

There are various threads and external information on various sites about how to sort this.

They vary from blasting the sensor with air, using a sensor cleaning kit with isopropyl alcohol plus wipe, to an indignant "I wouldn't touch the sensor at all" from a man in the Spectrum shop in TCR

It's really up to you, have a read around.

George Lazarette

Link Posted 07/09/2004 - 09:14
As the 'Phone says, there are various options. It is odd, though that yours developed this problem so quickly. I would take it back to where you got it and ask them to fix it, because it sounds as though the camera came with a dirty sensor.

Failing that, the first thing to try is to blast some air at the sensor, and in my experience this is often all that is required. So far, I have cured my problems just with an ordinary blower, but you can get compressed air in cans.

If that doesn't work, then you're into sensor cleaning, and this is either a DIY job (if you're brave), or something you can pay for.

With film, it's scratches on the neg. With digital, it's sensor dirt. Nothing is perfect.

Prevention is better than cure. Avoid changing lenses in dusty places.


Link Posted 07/09/2004 - 22:26
Thanks for your help guys,
looks like a few hefty(ish) puffs of air from a hypodermic syringe has done the job. 'Clean room' lens changing from now on?!


Link Posted 30/11/2004 - 16:41
If only!

I'm now looking for a 17mm to 400mm f2.8 zoom lens with macro. It's very hard to change lenses on the back of a jeep in the Tsavo Game Park without getting a bit of dust in... but I've tried changing them inside a clear carrier bag. In the UK Morrisons Supermarket are handily doing a clear carrier bag!!


Link Posted 01/12/2004 - 13:23
All sensors will inevitably come with a few 'dead' pixels, but these shouldn't be obvious. You might pick them up if you zoom in in Photoshop.
I would advise against using compressed air cans to blow the sensor. They blow cold air that can cause water vapour to condense on the sensor!! Stick to an old fashioned blower.
Just joined forum, look forward to talking to fellow pentax users.
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