RAW photo shooting

Started by dark-shadow, October 12, 2014, 11:06:42 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

dark-shadow

Hi,

I'm completely new to RAW photo shooting. The RAW pictures I took with my EOS 550D are rather noisy. I realized that I have to post-process RAW images on my own, using RAW editing software. Have I understood it right that noise reduction is usually done by the camera, but for RAW images I have to do it manually? If so, how are other people doing this?

Here is what I want to achieve:
* Take photos in RAW mode (mainly to be able to use advanced features like aettr and dual_iso)
* Post-process (preferably automatically) via script or using graphical tools like RawTherapee (or any other Linux software if someone can recommend one)
* Save the results as regular JPEG (I don't want or need to keep the RAW images around, except perhaps for some particular photos). Image dimensions can be appropriately the same as regular JPEGs written by the camera, or any other of those standard sizes.

My primary concern is the noise, though; I wonder, did I do something wrong regarding the way I shot these pictures?

garry23

May I suggest you first get used to shooting in RAW without using any additional ML functionality.

Your camera should have come with software to process RAW images.

Additionally think about software such as Photoshop Elements.

The thing with RAW us that you need to create the image in post.

Once you better understand the strengths of RAW, then move on to ML enhanced RAW capture.

As for noise, use base (100) ISO, for minimum noise and, of course, seek out optimum exposure.

Walter Schulz

And I would think twice about not saving your RAW files. Over time I saw various enhancements in RAW converters and add-ons. After driving some older RAWs through my workflow again I sometimes was glad having taken the effort a second time. Not always, of course!
I found a link:
http://www.pentaxforums.com/reviews/linux-for-photography/introduction.html

PSE has WINE rating "silver" so it may run in Linux
https://appdb.winehq.org/appview.php?appId=1794

dark-shadow

Long time ago, but... thanks for the suggestions.

I didn't have a problem with not using the correct RAW software nor understanding RAW. It was simply that the settings I chose for taking pictures were too demanding for my equipment, producing the noisy results. No software can help with that though GIMP with the GMIC plugins did a hell of a job at that when I think about it. BTW: The software that came with my camera and runs in Windows sucks, compared to the alternatives.

For linux, I have started working with RAW using these two applications:

1) RawTherapee: I found this to be a bit more intuitive to use first. Although it claims to have good support especially for ML, the default settings it chooses seem to be a contradiction to these claims. But I do like the workflow and user interface a bit more than that of Darktable.

2) Darktable: This opens the DNG files with proper parameters. If I only want to open the files and export them to JPG, without applying many other tweaks, then this is what I use now.

So far, both apps do not have native support for Dual-ISO yet. Maybe someone writes a plugin etc. in the future.

garry23

@Dark-shadow

You don't need an app to process dual-ISOs.

Just use the standalone .exe.

As for noise, if you 'just' use ETTR and not worry about mid or shadow S/N, and set an ETTR exposure on a contrasty scene, ie bright highlights, this will push the main scene down in exposure. Remember ETTR is trying to stop the highlights from being over exposed. So use the S/N options, which will protect those areas at the expense of the highlights.

If you have a 'normal' scene and ETTR and use Dual, you are using the optimum strategy.

If the scene has more contrast than 'normal', then you are advised to adjust the ETTR settings or bracket.

BTW if you bracket, use ML auto bracketing and set your base exposure off the shadow areas where you wish to see details, ie use the ML RAW spotmeter on EV to, say, set the shadow detail area to -2-3Ev. Doing this will give you a perfect bracket set.

Good luck

dark-shadow

garry23, thanks for your tips, I will try to improve my results with these suggestions. My 'normal' RAW pictures are pretty good with AETTR, but I have already experienced some limits of dual iso, e.g. chroma noise on pictures with water etc., and the pictures I take in dark areas are still really bad with lots of noise, and sometimes blurred. It will take me some more experiments to figure out how to get this right.

garry23

@dark-shadow

IMHO don't waste your time trying to 'get it right'. You wont, as no two scenes are the same.

Just gauge when to change your exposure setting strategy.

In very contrasty scenes, dual-ISO may not help that much. I use Dual-ISO with ETTR, to protect the highlights, and 'lift' the shadows, but 'only' by about 2-3 Ev.

If you visually can't gauge the DR of the scene, use the ML Spotmeter to 'scan' the scene, to see the EV difference between say the shadows you are trying to capture detail in and the highlights you wish to not see blown out. These two numbers will give you a feel for which exposure strategy to use, eg:

1. Simple Canon - but why bother if you have ML loaded :-)
2. ML ETTR
3. ML ETTR + Dual-ISO
4. ML bracketing

I find the ML spotmeter a real boon: a RAW spotmeter that, on most, lenses is less than an external 1-deg spotmeter.

Good luck with the experiments :-)

Cheers

Garry