I also want to understand why I don't get any hot pixels when I use the
Photoshop CS raw converter and create a tiff file that way. Perhaps I
need to tweak the settings.


 On Mon, 2004-03-15 at 10:40, Dr. Shaun Canning wrote:
> Hi Frits, 
> 
> It seems like the hot pixel phenomena are pretty widespread, but then some dont seem 
> to have any at all. It will be interesting to
> see what the 'average' number of hot pixels is amongst those who submitted results 
> to Rob.
> 
> Cheers
> 
> Shaun
> 
> Dr. Shaun Canning
> Cultural Heritage Services
> Lawrence Way, Karratha, 
> Western Australia, 6714
> Mob: 0414-967 644
> 
> [EMAIL PROTECTED]
> www.heritageservices.com.au
> 
> 
> 
> -----Original Message-----
> From: Frits Wüthrich [mailto:[EMAIL PROTECTED] 
> Sent: Monday, 15 March 2004 7:37 AM
> To: [EMAIL PROTECTED]
> Subject: Re: *ist D Pixel Comparison Test
> 
> I ran this test using a TIF file, which is recommended, as a jpg might
> cause false reporting on hot pixels which are artifacts of jpg
> compression.
> When shooting RAW and using the converter of Photoshop CS to create a
> TIFF, I didn't find any hot pixels.
> With TIF writing by the camera on the flash card directly however, I did
> find hot pixels, no dead ones. I did the test with Noise Reduction (NR)
> on and NR off.
> 
>       NR off  NR on
> 30 s  834     3
> 15 s  82      5
> 8 s   31      0
> 4 s   25      0
> 2 s   15      0
> 1 s   17      0
> 1/2 s 11      0
> 1/4 s 5       0
> 1/8 s 2       2
> same results up to and including 1/4000 s (2 hot pixels with NR off and
> NR on).
> 
> On Sun, 2004-03-14 at 00:39, Dr. Shaun Canning wrote:
> > Hi guys, 
> > 
> > Anyone willing too take part in a little experiment with your *ist D? I know how 
> > you guys all love comparing lenses and gear from
> > time to time, so hopefully a few of you might help me out. 
> > 
> > I want to compare the number of recorded 'hot' pixels with other owners to see if 
> > the results I got from testing are normal or
> > otherwise. It'll take about 3/4 of an hour to run the tests the same way I did. 
> > 
> > I used a little utility called 'Dead Pixel Test' which is available at 
> > http://www.starzen.com/imaging/deadpixeltest.htm
> > 
> > I took a series of shots with the following set-up. 
> > 
> > 1. Lens cap on
> > 2. Viewfinder cap on
> > 3. Manual mode
> > 4. Manual Focus
> > 5. JPEG Highest Quality 
> > 6. F8.0 using FA 24mm (not that the lens should really matter)
> > 7. Noise reduction On
> > 
> > I took frames with shutter speeds ranging from 1/4000 down to 2 seconds (all 
> > speeds in between). I then used the Pentax Photo
> > Browser to export a *.csv worksheet to work on in excel. Then I ran each frame 
> > through the test program, as per the instructions.
> I
> > set the Luminance threshold to 60, and the Dead Pixel threshold to 100. 
> > 
> > Thankfully, I recorded no dead pixels, and the worst result was a total of 4 'hot' 
> > pixels at 1/8 and 1/6 sec. noise reduction does
> > cut in at 1/4 sec, eliminating all 'hot' pixel occurrences from 1/4 too 2 secs. 
> > 
> > As other have pointed out, some of the images I uploaded yesterday definitely 
> > display hot-spots caused by these 'hot' pixels. What
> I
> > am interested in is the results that anyone else may get to compare to my camera. 
> > 
> > Thanks in advance, 
> > 
> > Shaun
> > 
> > Dr. Shaun Canning
> > Cultural Heritage Services
> > Lawrence Way, Karratha, 
> > Western Australia, 6714
> > Mob: 0414-967 644
> > 
> > [EMAIL PROTECTED]
> > www.heritageservices.com.au
> > 
> > 
> > 
> > -----Original Message-----
> > From: Dr. Shaun Canning [mailto:[EMAIL PROTECTED] 
> > Sent: Sunday, 14 March 2004 6:37 AM
> > To: [EMAIL PROTECTED]
> > Subject: RE: *ist D Photos
> > 
> > Thanks Mark. I would have liked the 'in flight' shot to be a bit sharper, but you 
> > know how fast these little buggers move. It was
> > more luck than good management. I'm pretty happy with the overall performance of 
> > the *ist D though, even if I do have a couple of
> > 'hot' pixels. 
> > 
> > Cheers
> > 
> > Shaun
> > 
> > Dr. Shaun Canning
> > Cultural Heritage Services
> > Lawrence Way, Karratha, 
> > Western Australia, 6714
> > Mob: 0414-967 644
> > 
> > [EMAIL PROTECTED]
> > www.heritageservices.com.au
> > 
> > 
> > 
> > -----Original Message-----
> > From: Mark Cassino [mailto:[EMAIL PROTECTED] 
> > Sent: Sunday, 14 March 2004 2:54 AM
> > To: [EMAIL PROTECTED]
> > Subject: Re: *ist D Photos
> > 
> > Cool photos, especially the dragonflies in flight.
> > 
> > I was wondering how the *ist-D would do with bugs - looks great! (Mine 
> > arrived with the first snow, so no chance to test it on insects yet).
> > 
> > - MCC
> > 
> > At 12:41 PM 3/13/2004 +0800, you wrote:
> > 
> > >Hi gang,
> > >
> > >Here are the results of my first foray into the bush with an *ist D. all of
> > >the shots were taken with the *ist D, battery grip, FA 100mm macro. All were
> > >handheld. Photoshop work was limited to sharpening and adjusting the levels
> > >a bit.
> > >
> > >The files are all in the 1-3 mb range, so be warned, they'll take a while to
> > >come down the pipe via a 56k modem. None of them are resized.
> > >
> > >http://www.heritageservices.com.au/Pentax%20ist%20D%20Photos/Web%20Gallery/i
> > >ndex.htm
> > >
> > >Tell me what you think?
> > >
> > >Cheers
> > >
> > >Shaun
> > >
> > >Dr. Shaun Canning
> > >Cultural Heritage Services
> > >Lawrence Way, Karratha,
> > >Western Australia, 6714
> > >Mob: 0414-967 644
> > >
> > >[EMAIL PROTECTED]
> > >www.heritageservices.com.au
> > 
> > -----
> > 
> > Mark Cassino Photography
> > 
> > Kalamazoo, MI
> > 
> > http://www.markcassino.com
> > 
> > -----
> > 
> > 
> > 
> > 
> > 
-- 
Frits Wüthrich <[EMAIL PROTECTED]>

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