Dust

[noimmunity]

My photos always have a few spots (tiny bright holes)that must be from dust. I've not found any sensor cleaners in Taipei, so after reading up I've been using a blower followed by a gentle wet cleaning with a soft cloth. It is still impossible to get the sensor fully cleaned. Photos taken with the lens cap on will show numerous tiny bright spots; photos of a white paper taken at f22 will show a few dark blotches. Should I go look for a brush or buy the brush from Copperhill?

 

[joachim]

My photos always have a few spots (tiny bright holes)that must be from dust. I've not found any sensor cleaners in Taipei, so after reading up I've been using a blower followed by a gentle wet cleaning with a soft cloth. It is still impossible to get the sensor fully cleaned. Photos taken with the lens cap on will show numerous tiny bright spots; photos of a white paper taken at f22 will show a few dark blotches. Should I go look for a brush or buy the brush from Copperhill?

Sorry you lost me. I take it you are writing about a digital camera. Dust on a sensor will not lead to bright spots (like with slide film, this will always leave dark spots). Reads more like stuck, hot or dead pixels. Pixel mapping would be the cure for that one. Not sure I missed the boat here.

 

[noimmunity]

Thanks for clarifying that for me. (Yes, it is a digital camera--the RD-1, in fact).
I was hoping it was just dust, but had been wondering if they weren't pixel problems...but since I had tried once the dead pixel correction to no avail, I thought it must be dust. Turns out that was wishful thinking.
Anyway, I repeated the dead pixie procedure several times and now those few annoying bright spots have all disappeared.
A test shot of totally black reveals nothing but black. A test shot of white at f22 out of focus reveals a very even white image, demonstrating lack of dust.
Now my next question is: how do dead pixels occur? I mean, is there anything that can be done to prevent this? Is it a recurring problem?

 

[Tuolumne]

And what happens to those dead pixels when they are "fixed"? Does it map in a new value that is an average of the surrounding pixels? or what?

/T

 

[noimmunity]

I'm afraid that the above-mentioned averaging is what happens, but cannot verify this. What seems strange to me is that the process has to be repeated several times for full effectiveness. But I can't notice any difference in the photos (other than the obvious correction of dead pixies).

 

[MCTuomey]

you might consider the following alternative for sensor cleaning:

http://www.birdsasart.com/lenspens.htm

i've used it on my canon digi gear with success (no connection to the seller)

 

[navilluspm]

Regarding Hot Pixels

Regarding Hot Pixels

Hot pixels are bright. Dead Pixels are black

Here is a post I made on dpreview regarding a hot pixel problem for a Fuji s6000fd. The recommend free fix will work for the RD1 as well.

http://forums.dpreview.com/forums/read.asp?forum=1012&message=27190666

 

[noimmunity]

So, I have blundering into a realization of the differences between hot pixels, dead pixels, and dust.
Coincidentally, I was just testing long exposures with lens cap on this morning, so navillus' post is welcome. I haven't had much experience with digital, so I hadn't realized hot pixels could be a problem on long exposures. Seems to have hit the nail on the head. Thanks!
Have other RD-1 users had similar experience???

 

[RML]

Have other RD-1 users had similar experience???

Of course, I'd say. But the R-D1's software takes good care of them. And dust... well, that's easy. I've used alcohol ketonatus and Q-tips. Easy and, most importantly, also very cheap.