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tickbird [deleted] says:
I have been converting raw files to Tiff using bibble. making the adjustments there before merging the tiff files. Touch the curves, hue etc in PS. I still seem to be getting too much noise. So any advice would be appreciated as well.
Posted 38 months ago.
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gabsriel [deleted] says:
Yes we need advices !
Posted 38 months ago.
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ONE raw file is better than 5 tiff, you don't have to bracket raw files to obtain HDR, just open the raw and save thre or five version changing the EV:: this is the meaning of RAW in HDR!!!!
shot from a single RAW file taken with an Olympus SP320
Bracketing you'll never be able to freeze a scene!!!
Originally posted 38 months ago.
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mikeletron2 edited this topic 38 months ago.
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@mikeletron2: for someone who is fortunate enough to be able to shoot RAW you are still wrong. 1 RAW can never capture the range (hence the name high dynamic range) of multiple exposures. Also shifting the exposure in some editing software cant do this cause you can not create more data than is captured already. You can use RAW when shooting moving objects yes, but than its just a tonemapped RAW and not HDR. The tonemapped RAW you are showing is quite hideous if i may say so lol.
Posted 38 months ago.
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gabsriel [deleted] says:
Thanks g.h.vandoorn. Now I've not to say that.
What do you think of my question ?
5 Tiffs or 5 RAWs ?
Posted 38 months ago.
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@ g.h.vandoorn: I still think you are wrong, as the best HDR shot come out from a single shot, but instead of discuting it please read these documents:
Tone Mapping and High Dinamic Range Imaging
HDR Photography
and then visit this group:
HDR from a single RAW
the fact is simple: the sensor capture a very higher dynamic range than the one used in the processed JPG file recorded, normally this exceding data is lost, in the case of RAW file you bypass the "engine" of the camera and record the whole data direct on the card, you can process this big amount of data in a second time through a software, and it's not a case that this process is often defined as "developing". Among it in certain cameras (ie: Kodak P880) you can develop JPGs files out of a single RAW direct with the camera through a dedicted software.
I wish it was clear.
***
For wath concern my hdr "Japanese turists over Santa Trinita bridge, Florence" I didn't posted for artistic purposes just to show the fact that IS possible to get a HDR from a single RAW, anyway for your information this shot as been viewed 366 times and commented 23 times.
Also from a single RAW for your LOLs:
Originally posted 38 months ago.
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mikeletron2 edited this topic 38 months ago.
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gabsriel [deleted] says:
Ok i will read the links after this comment.
The picture you're posting is not HDR 32 bits. It's simply LDR tone mapped.
Tone mapping is a function that compress the dynamic range to make it visible in the screen. Tone mapping creates a LowDR picture.
But i will read the links you gave. Perhaps there is a schism in scientific community about HDR !
Posted 38 months ago.
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gabsriel [deleted] says:
Thank you for the doc. It proves that you're wrong :
"There are two main methods for generating HDR imaging. The first method is by using physically based renderers, which produce high dynamic range images generating basically all visible colours. Another way to generate HDR imaging is by taking photographs of a particular scene at different exposure times [2]. By taking a series of photographs at different exposure, all the luminances in the scene can be captured as shown in figure 3a. After the images have been aligned and combined into one single image, the camera’s response function for each of the RGB channels can be recovered and stored. "
1 Raw is better than 1 jpeg or even 1 Tiff
But 3 jpegs are far better than 1 RAW.
Our screen are not able to reproduce HDR. That's why we use tone mapping in Photomatix, to make all the tones be visible in a LowDR display.
When we talk about HDR and when we show our work, like this :
We say : "It's HDR".
In fact this is not HDR. It's LowDR produced with a tone mapping.
Do you know that we can tone map a jpeg and that we will have the same result as your pictures or mine ?
Wanting to make HDR with 1 RAW file isn't a bad idea beacause the range of RAW is important, but It will NEVER make a true HDR, just a "beautiful" LowDR tone mapped from a lowDR picture.
RAW is not HDR
Originally posted 38 months ago.
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gabsriel edited this topic 38 months ago.
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gabsriel [deleted] says:
I suggest you that you take a shot from the sky and overexpose it.
In the pictures some details will be available and other burned.
Take your RAW, make your different RAWs as you wish. Then make the Photomatix stuff.
You will see that NOT ALL the details will remain.
That's because the different exposures of your RAW, will not be true different exposures.
If exposure would not be important , then digital camera would just have to take 1 stop picture in RAW. Then what's the point to have an aperture ans speed priority (PASM) ? The imaging engeneers are just mad ?
Originally posted 38 months ago.
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gabsriel edited this topic 38 months ago.
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gabsriel [deleted] says:
en.wikipedia.org/wiki/High_dynamic_range_imaging
The Photomatix page :
www.hdrsoft.com/
" What are the differences between Exposure Blending and HDR/Tonemapping?
Both processes start from the same source files: differently exposed Low Dynamic Range (LDR) images. And both attempt to produce as final result an LDR image that shows tonal details of the entire dynamic range captured by the different exposures.
The differences are in the process itself. Exposure Blending consists in combining the differently exposed images in such a way that highlights details are taken from the underexposed photos and shadows details from the overexposed ones. Since the bit-depth does not change throughout this process, the basis of Exposure Blending algorithms is a type of weighted average of the source images.
The advantage or Exposure Blending is that it is easy to understand and you can see what you are doing. Also, it is rather familiar to photographers who are used to doing this process manually in image editing applications. In Photomatix, the Exposure Blending functions are named "Highlights & Shadows" and are available under the menu "Combine".
HDR Tone Mapping is composed of two steps. The first step creates an HDR image from differently exposed photos. This HDR image can not be displayed correctly on a Low Dynamic Range monitor, which is why a second step called Tone Mapping is necessary. Tone Mapping consists in scaling each pixel of the HDR image, so that details in highlights and shadows show correctly on monitors and prints (those details are available in the HDR image but not directly visible in both highlights and shadows because of the low dynamic range of the display).
Tone Mapping algorithms vary from a simple gamma curve (which is often what cameras are doing when converting 12-bit RAW data to 8-bit JPEGs) to more complex operators commonly divided into two categories:
· Global operators: mapping depends on pixel's intensity and global image characteristics, but not on spatial location
· Local operators: mapping takes into account the pixels' surroundings (in addition to intensity and image characteristics).
The main advantage of global operators is fast processing. Local operators require longer processing times but they are better at producing a "good-looking" photograph (the human eye adapts to contrast locally). The Tone Mapping algorithm of Photomatix Pro belongs to the category of local operators.
The pros and cons of Exposure Blending vs Tone Mapping in Photomatix Pro are detailed under the section below."
Read the FAQ of Photomatix to understand more and more :
www.hdrsoft.com/resources/dri.html
Posted 38 months ago.
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gabsriel [deleted] says:
Ok sorry for my rudness.
I understood that my question (5 RAWs or 5 Tiffs) doesn't have to by asked in this beginner group.
I think I'm a beginner that's why I asked here. But I was wrong.
I will re ask in the HDR group.
Posted 38 months ago.
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@gabsriel:
Yes, our pics are LDR representations of HDR and, yes bracketed HDR can be better than single shot, but the FACT is that you can get three different dynamic ranges out of a single RAW file, maybe the total dynamic is not as big as in three bracketed shots but is going to be enough for generating an HDR and convertin it to 8bit x channel through tone mapping or other algorithms.
Bracketing can be better but you are going to loose al the "action" shots or get lost with phantoms.
Originally posted 38 months ago.
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mikeletron2 edited this topic 38 months ago.
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Not all Camera RAW files are equal as some maybe only 10,12,14, or 16 bit per channel depending on the camera. So you can imagine there would be a huge difference between a 10 and 16 bit per channel RAW file, but i would personally never convert a RAW into 3 JPEG. I would just tone map the RAW directly. But not all applications will allow that so you do what you gotta do. But i would think it would be easier and much more HDD space friendly to use an application to convert your RAW to something like HDR and then tone map if you can't tone map the RAW directly.
Originally posted 38 months ago.
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mtlockca edited this topic 38 months ago.
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gabsriel [deleted] says:
@mikeletron2 : I absolutely agree with you. And the single RAW tehcnique permits more sharped result. I thought that you really misunderstood what HDR is. So : big sorry.
Perhaps we may try to test if tone mapping on 1 raw is better than tone mapping with 3 modified RAWs.
I will try to publish this test.
Sometimes experimentation is better than words.
Posted 38 months ago.
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gabsriel [deleted] says:
I asked the same question there and made tests :
www.flickr.com/groups/hdr/discuss/72157594373203099/
Posted 38 months ago.
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gabsriel [deleted] says:
The first one is made with 3 RAWs made from 1 RAW : -1/0/+2
The second one is made with just 1 RAW
The process in photomatix is exactly the same.
And the picture are the same, except luminosity a little little different (it's because I chose asymetric EV).
So thanks to the result I had : tone mapping on 1 RAW and tone mapping on 3 versions of the same RAW give the same result !
Know we can save a lot of time.
Posted 38 months ago.
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@mikeletron2: I'm not convince@d by those "documents". The things is you can not capture the same big dynamic range with just one exposure (nothing related to file format). You are basically saying you have the same dynamic range when u shoot one RAW than when u take 5 pictures at different exposures. Using one exposure is nothing more than tonemapping one RAW.
Posted 38 months ago.
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The point is that you can edit your raw files changing exposure but a price is to pay.
If you take 3 bracketed pics in RAW, you can change the settings and make them look quite identical. What you (can) lose is (light) resolution or even details at low and high light.
From a raw file you can be able to get out something from a very dark object but you'll increase the noise.
RAW offers great flexibility and you can do things that you can't do with TIFF and JPEG, but its performance has limits too.
If RAW dynamic is beyond the 12 or 14 bits why they give us these limits? Why they don't give us an HDR image?
Using 1 RAW image can give you a good HDR image, depending on the software (Photshop needs at least 3 really different shots), but saturated light/dark will never come out. It depends on the image.
To my surprise, instead, it seems that using bracketed shots the HDR process reduces the noise.
Look at this pic (please look it at maximum resolution), for example. To me it seems more noiseless than the original RAW files.
Posted 38 months ago.
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gabsriel [deleted] says:
Yep. I agree with you.
But I think my question is still not resolved.
HDR is 32 bits floating points. And it's not 12+12+12bits...
So I think that creating an HDR picture with 3 RAW gives you the same DR than with 3 Tiffs.
So for noise correction I would recommend Tiffs (or RAWs develepped in camera RAW but the workflow will be very long...).
I hadn't got the time to make a test but someday (perhaps before the week end) I will post a comparison (with a tripod) of HDR Tiffs and HDR RAWs.
Posted 38 months ago.
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gabsriel [deleted] says:
I've got an interesting information !
Photomatix uses Dave Coffins Raw development algorithms : DCRaw library, which is good but not as relevant as camera raw (I think).
So if you want to make mutiple raw exposures for HDR, you shoul first use Photoshop.
Posted 37 months ago.
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@Mikeletron2,keep it up.im gong to try it,and your work is no different than Kris Kros ,its very upscale...
Posted 37 months ago.
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