Why is RAW noisier than Jpgs?

[nigel_keene]

I have just shot using RAW as I knew light was a problem at the venue I was at

and I thought RAW may give me more options. I found though that shooting at

1600 the images were far noisier that I have usually got from jpgs at the same

speed. Is there something in the PP that I should be doing? .......I would

normally add something like noise ninja anyway....but an explanation as to the

increased noise would really be helpful

[eugene_scherba]

In addition to doing some rudimentary noise reduction when

converting to JPEG, the camera also applies a tone curve

that "squashes down" shadows resulting in less visible noise, but

also in a loss of detail in these areas.

[nigel_keene]

So am I better taking off any default sharpening and noise reduction that CS2 has and then adding my own afterwards?

[saskphotog]

Sometimes I let the RAW processor deal with any sharpening, sometimes I remove it all in RAW processing and do it last. It depends on what I intend do to with the files after they are converted. RAW to Jpeg I often sharpen. RAW to Tiff I usually do not.

 

I believe if the absolute best quality you can produce (for very large printing for example) is the goal, then it is best to sharpen as the very last step in the process.

[beauh44]

<I>So am I better taking off any default sharpening and noise reduction that CS2 has and then adding my own afterwards?</i><P>

 

I think the general consensus is yes. Photoshop CS, by default, has a sharpening value of "25" and I can't recall what the anti-noise value is but it's probably close.<P>

 

Anyhoo, I slide both of those back to zero and if the image is noisy, use a product like Neat Image to deal with the noise, then sharpen according to output. Good luck!

[marknagel]

Nigel, try downloading the trial version of captureone. I did a test before I bought it by shooting 10-20 varying shots in raw/jpg mode, then did my absolute best to process the raw in Photoshop ACR and CaptptureOne. Every picture I processed in CaptureOne was better than ACR and Jpg, and about 1/4 or less the time to do. Mnay of the Raws did not turm out as good as the Jpgs, just the extreme ones (WB corrections, Exposure Corrections, etc).

 

M

[PuppyDigs]

If will help if you enable the auto noise settings in DPP 2.2 (preferences).

[digitmstr]

It all depends on the RAW conversion program you are using (and settings).

 

RAW doesn't do anything to the image, the program you use for conversion does. I use C1 PRO and it works great with my 5D files. I have also used the DPP that came with the camera but, no comparison IMO.

[kelly_flanigan1]

A jpeg scheme has to compress the image; averaging with its neighbors pixel values where blocks become the same value and tone to create a smaller file. Thus a jpeg from a raw or tiff file can have less noise due to this averaging. With a very mild compression ratio the noise will mosttly still be there; with alot compression the noise can many times be quashed and hidden.

[kelly_flanigan1]

Imagine you and your neighbors water bills are 30, 35, 40, 55, 25, 30, 35 bucks. <BR><BR>With jpeg compression the data might be five are 30 bucks; one is 40; one is 55 bucks with the 25, 30 and 35 "noise" lumped and lost into the 30 data set.

[r.sriram]

Another vote for Capture One. I've been playing with the trial version and it produces much more impressive images with far better colour accuracy and detail than I've seen from photoshop.

[alexandru_petrescu]

Nigel, it's normal RAW files show more noise than jpeg because they're raw. DPP (Canon's Digital Photo Professional) knows to eliminate this noise very well, when converting to jpeg, I'm quite happy with results even at 3200.

 

But. But. There are some issues with some jpeg viewers that won't understand correctly the jpeg generated by DPP and still show eg the white little spots on a black background when viewed reduced size. It's a particular case I was in.

 

So, if you offer details about: what viewer? what pp you used to convert from raw to jpeg? PC or mac? then useful step-by-step advice can come up.

[nigel_keene]

Thanks for your comments and advice so far. I have tried reducing the CS2 sharpening and noise reduction to 0 and then have added shapening and nr after converting to jpg and this has definately helped .......might have to give Capture One a go tho!