Dead Pixel on JPEG But Not RAW

M

martinledford

Newbie
Local time
11:44 PM
Joined
Mar 17, 2005
Messages
4
I purchased an RD-1 this week and shot RAW format for two days. Today, I shot B&W JPEG (H) and noticed a dead pixel in the exact location on each B&W JPEG image. However, when I switched back to RAW the dead pixel was no longer there. Should I be concerned about this and return for an exchange? Or is this related to some internal algorithm regarding noise reduction?

Thanks,
Martin
 
If everything else is working well on the camera, I wouldn't return it for just the one dead pixel.

Cheers,

Sean
 
maybe I would return it thinking of the high price of it, it should be flawless
 
Martin, if I were you I'd read Jorge's post on the slow death of digital. ;) (Just funning with ya.)
 
Martin,

Frank wasn't serious. He's just messing with you.

Sean
 
Martin,
If you have read the other posts about Stuck/Hot pixels you will see that this is not uncommon with the R-D1. I have three stuck pixels and personally have not seen an R-D1 without at least one. Given that many exchanged cameras have been worst in this and other respects I would keep the one you have unless there are any other serious faults.
 
Last edited:
If one has an R-D1 with accurate rangefinder focusing, a viewfinder mounted truly square in the camera, just one hot pixel and no other faults...hold onto it for dear life. As much as I love this camera (and I do) one cannot deny that some of them have had defects of one kind or another. But a good copy of an R-D1 is certainly worth having. Should there be better QC for $3000? Absolutely. But...the situation for now is what it is and there are some very good examples of the R-D1 out there - I have one of them.

Jim,

What do you shoot that makes having three bodies desirable? news? weddings?

Cheers,

Sean
 
Sean,
Guess I should always get someone to proof read my posts so they make sense. I have now edited to read three "stuck pixels". I have checked a total of three R-D1's at my dealer and on the Epson stand at Focus on Imaging and all have had stuck/hot pixels when the iso is pushed to 1600.

Now the thought of owning three R-D1's each with a different "Star" lens from your ongoing tests. :) :) :) It's just the money thats the problem. :bang:

Thank's for pointing out the lack of clarity.
 
I have just read Frank's thread on Good things coming in pairs.

Perhaps I do need 3 R-D1's just to up the ante! :p :)
 
Based on what I know so far, if money were no object, I'd indeed carry three R-D1 bodies for working in fast changing circumstances:

R-D1 with Voigtlander Ultron 28/1.9 $3000 + $440.00
R-D1 with Leica 35/1.4 ASPH $3000 + $2795.00
R-D1 with Leica 50/1.4 ASPH $3000 + $2495.00

Total cost: $14, 730 (although I've already got the first body and the Ultron so that's a start)

One of my tasks today is to start to get a feel for how close the Nokton 1.5 comes to the Leica. The CV 35/1.2 is a good lens but, so far, it's not a match for the Leica 35/1.4.

Cheers,

Sean
 
Hot/Dead Pixels on JPEG vs. RAW

Hot/Dead Pixels on JPEG vs. RAW

Hey, Guys:

Thanks for your responses to my question. However, I am still confused as to why when shooting 1600 I would see a hot/dead pixel on a the JPEG image but not on the RAW image at 1600. These shots are the same image at the same time.

Thanks,
Martin
 
Martin, can you please clarify? Do you see the 'non'-hot pixel on a tiff or a jpeg you've processed from the RAW?

I imagine that the hot pixel is below the noise threshold for the RAW conversion (there will be some background noise reduction), but is seen as a 'feature' by the on-board jpeg algorithm, which can then be amplified in the compression process.

I have a 1-pixel hotspot in RAW, which becomes a 5-pixel star in jpeg. Not quite the same case, but perhaps a similar process?

cheers
Phil
 
pfogle said:
Martin, can you please clarify? Do you see the 'non'-hot pixel on a tiff or a jpeg you've processed from the RAW?

I imagine that the hot pixel is below the noise threshold for the RAW conversion (there will be some background noise reduction), but is seen as a 'feature' by the on-board jpeg algorithm, which can then be amplified in the compression process.

I have a 1-pixel hotspot in RAW, which becomes a 5-pixel star in jpeg. Not quite the same case, but perhaps a similar process?

cheers
Phil
Click to expand...
Hey, Phil:

Thanks for the response. My test involved shooting a dark wall twice. The first time using RAW at 1600. I then use the Epson RAW converter in PS (Mac version) and convert with standard settings 16-bit into PS. Then, I shoot the same wall scene with JPEG High @ 1600. I use "standard" settings in the camera set-up. I've also used NR set to highest setting. I open this image in PS as well. When I compare the RAW version to the JPEG version, I see a hot spot (same place every time) in the JPEG version but it's not there in the RAW version. I find it odd that the RAW version never shows the hot spot but the JPEG does.

Thanks for your help.
Martin
 
well, I think you're lucky it's only in the jpg! It's a drag though, when you need jpg. Still, they ususally aren't visible in prints.

As far as NR goes, I'm not really sure, but I think that the noise reduction in the built in film settings are for shutter speeds of 2 secs an over, using dark field subtraction. At least, I think that's true if the NR is set to 'high'. Obviously, they'd use a different method in PhotoRaw.

Out of interest, do you see the hotspot if you make a jpg from the RAW, rather than 16bit tiff?

cheers
Phil
 
You must log in or register to reply here.
Back
Top Bottom