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St*wart [deleted] says:
www.luminous-landscape.com/tutorials/hdr.shtml
Posted 38 months ago.
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gabsriel [deleted] says:
Thank you.
I've read :
"If you have done the shots in RAW mode you will first need to process the files, preferably into TIF or PSD format. Ideally you want to keep them in 16 bit mode during RAW processing, though if you have been using a high-res digital back or camera, seven files of 100MB or so each can be too large for all except the most RAM enabled and fastest computer to handle."
Photoshop CS2 and Photomatix can merge directly the RAW files.
This is what I use.
My native RAW files are 12 bits depth (as almost all the digicam).
If I develop them in PSCS2 I will have 16 bits depth TIFF files + noise suppression. Then i understand that it's better to have 5 Tiffs (16 bits) than 5 RAWs (12 bits).
Thanks to you I 've resolved my problem !
Thank you !
Then 5 Tiffs (made in Photoshop from 5 RAWs) are better than 5 RAWs to make a good HDR pic !
Posted 38 months ago.
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A 12-bit RAW file will always contain the most information, even if you convert them to 16-bit TIFF files. But I suppose you know that.
Noise can be a problem whether you use RAW, TIFF or JPEG, and it can be amplified by the HDR process. I don't know if it's worse with unprocessed RAW files, but I haven't had any problems so far.
But, of course, if you have a good noise reduction algorithm, you should use it, if necessary. Just keep in mind that an aggressive NR filter can reduce the image quality to the point where you might just as well have used JPEGs to begin with.
Incidentally, why use 5 files? Which EVs do you use?
Posted 38 months ago.
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gabsriel [deleted] says:
5 photos from -1EV to +1EV
I've made a test.
The first picture : 5 tiffs created in camera RAW with 25 to color noise reduction, photomatix fusion + tone mapping
The second picture : 5 RAW in photomatix, batch mode (just a WB error, it's my fault so don't look at the colors)
Posted 38 months ago.
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gabsriel [deleted] says:
The same thing with a bypass filter 2.5 radius :
Difficult to say which is better.
Noise reduction lowers the sharpening and with a sharpening it remains some details.
With the RAWs there is much more details...
Careful : these pictures was taken without a tripod.
I have to test the difference between RAWs and Tiffs with photo taken with a tripod.
Posted 38 months ago.
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gabsriel [deleted] says:
I profit to publish the entire HDR picture. I choose the "5 RAW process".
It's too much soft...and it's my fault.
But I'm still not sure what I have to choose...
Posted 38 months ago.
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If you are only shooting over a range of +/- 1EV on a landscape like that, don't use five images, it just isn't necessary. Even with a small sensor digital camera, 1 EV bracket steps are fine. With a DSLR, you should be able to use 1.5 to 2 EV bracketing intervals. You will get an improve in sharpness by using less images in a scene like that just because there is less movement in the leaves and foilage.
Posted 38 months ago.
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@gabsriel:
Thanks for posting you results! It's a bit difficult to evaluate the amount of noise when looking at the foliage, but it seems the difference is marginal, at least in the shown crop.
It's a beautiful HDR picture! But, yes, the larger versions clearly reveals that the camera was handheld. I'm amazed that Photomatix isn't better at auto-aligning the images. Have you tried to align them manually?
@avidday:
I agree. 1.5 to 2 EVs is better. Shorter intervals just produce redundant information that doesn't contribute to a wider dynamic range.
@gabsriel:
If you insist on 5 RAW/TIFF images, then try e.g. [-4][-2][0][+2][+4] EV or [-3][-1.5][0][+1.5][+3] EV. And do get that tripod! ;-)
Posted 38 months ago.
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gabsriel [deleted] says:
@avidday : thank you for the advice !
@Certassar : I haven tried to align them manualy. But there was wind... I know that using a tripod is far better but sometimes I forget it or I just can't use it...
Fur the +/- EV I think I have a problem. Maybe I made a mistake. I've to verify what I said.
Ok my SLR is a little weird when he indicates EV in bracketing mode. So I use +/- 2 EV. And it seams that I can't bracket further...whereas I've got +/- 5 EV range...
Posted 38 months ago.
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To put this into some context, this was a +/- 1EV raw bracket in a scene with a lot of contrast, shot handheld (carefully, mind you) and combined with Photomatix. There is very, very little noise, there is good sharpness (even down to preserved CA from the ultra wide angle lens around the snow on the rocks in the foreground). The is an old rule - try and get as much right when as possible you shoot the image, then there is less work to be done in the darkroom later. Replace darkroom with postprocessing and I think it still holds.
Posted 38 months ago.
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gabsriel [deleted] says:
Thank you.
Then have I to bracket with EV compensation "to the right" ?
I think for really really contrasted scenes it's quite difficult, because preserving the sky is so much important...
Posted 38 months ago.
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It depends a little on what you are trying to do. For daytime skies, you usually want underexposure to bring out contrast and detail in clouds. If the sky doesn't have a lot of detail, then it usually isn't worth going too far - you can get the same feeling by increasing foreground dynamic range, like that one I posted. The effect is like using fill in foreground flash, but without the hassle.
Posted 38 months ago.
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gabsriel [deleted] says:
Thank you very much for the advice !
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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now correct me if I am wrong - and an unashamed non techie - but dont RAW files contain ALL information captured on the processor and as such you shouldn't NEED multiple raws to complete HDR as it is already there.
To keep sky contrast you can always run a high pass filter a number of times to kick up resolution - stuck in customs has a really good tutorial on layer masking to achieve high detail skies .... www.stuckincustoms.com/
Posted 37 months ago.
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gabsriel [deleted] says:
I didn't reach the tutorial, sniff...
1 Raw files containt much more information than 1 jpeg file.
But the information that is on a RAW file isn't unlimited. It corresponds to the dynamic range of the camera.
And what human is capable to see is a much more dynamic range than digicam.
HDR is a means to increase the dynamic range by adding several différent files. The DR is able to go further than human perception, because human eyes have a non linear perception (our eyes adapts automatically to the light), and digicam sensors have linear cupturing. That's why an HDR pic, tone mapped seems unreal. And that's why when you use photomatix you have this little eye droper why permit to see than real range of the photo.
For exemple : if in real life the DR is 0 to 20 stops. It's just an example !
1 RAW could have 7 stops : so 0 to 6 or 1 to 7...
If you take 5 RAWs you could have this : 0 to 6 + 3 to 9 + 6 to 12 + 9 to 15 + 12 to 18.
Shooting a scene with different exposures can expand the DR of the final result.
With 1 RAW, you just can't.
And the result you see on Internet when people make "false" HDR with 1 RAW is in fact a tonal compression of the DR of 1 single file. It's an illusion of HDR.
Posted 37 months ago.
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but when u use different raws they all look the same.... the three of them if u take them with a tripod.... what 's the difference between them? why is the info in them different between them... if the light conditions are the same and the exposure will be ajustable but the same for all of them?
Posted 37 months ago.
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now correct me if I am wrong - and an unashamed non techie - but dont RAW files contain ALL information captured on the processor and as such you shouldn't NEED multiple raws to complete HDR as it is already there.
OK then, you are wrong.
Raw files certainly contain all of the picture information captured by the sensor, but the whole point it that the sensor has finite dynamic range (most consumer DSLR cameras are in the 8-9 stop range, Fuji's current CCD can record about 10). Usable dynamic range is closer to 6 stops. Unlike film, imaging sensors do not have a graceful roll off into white or black, you get hard highlight clipping and shadows are pulled hard to black. Further to that, sensors have a pretty harsh noise floor, meaning that it is difficult to push the bottom third of the exposure histogram by more than about a stop without introducing a lot of shadow noise into the image. If you are exposing a scene with a lot of dynamic range, it simply is not possible to record all of that range in a single exposure. The only way to achieve that is via multiple exposures - effectively recording the scene within a set of overlapping finite exposure windows. and then reassembling the final exposure via one of the HDR algorithms.
Originally posted 37 months ago.
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avidday edited this topic 37 months ago.
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gabsriel [deleted] says:
Indeed.
@matt4ya : if your camera takes the same RAW when it brakets, it's a wrong braketting. Some cheap cameras take 3 shots in braketing but it's not 3 different exposures, it's a post process made by the DSP of the cam...well very bad...
"Real" braketting (wich is present in the SLRs and severals point-and-shoot) really takes different shots. So you have differents RAWs.
My Olympus E-1 can take 5 different RAWs files in braketing mode.
Canon 350D, 400D can take 3 different RAWs, etc.
Posted 37 months ago.
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thanks for the tutorial- I lost you around harsh noise floor but I stand corrected.
Posted 37 months ago.
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I'm not clear why I should need more than two, or ideally three, RAWs over a 4 EV range to capture at least 10 stops. Am I missing something?
Posted 37 months ago.
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gabsriel [deleted] says:
@nicoatridge : you're right, 2 or three are enough.
But sometimes not.
Originally posted 37 months ago.
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gabsriel edited this topic 37 months ago.
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OK .. I listened and digested ..... but am looking for some feedback -
To overview I have a nikon and Photoshop CS and Photomatix ...... and heres the pain
If I run the NEFs ( Nikon RAW) through the batch processing of the Photomatix there is often chromatic abberation around white surfaces ....
The only way to remove this is to run them through PHotoshop first BUT .. CS does NOT read NEF - you have to convert them to Digital Negative first .(DNG)... and then save them down to PSD or TIFF BUT Photomatix does not read DNG.- although it will read tiff.
So My Only choice is to Bracket with TIFF ( at best Floating point Tiff) ...
I have tried to manually build HDR from 3 5 and 7 RAW files on CS and it takes Days ....unless I am missing a trick
What are my options ............
Posted 37 months ago.
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gabsriel [deleted] says:
I think you can install the last version of camera raw in CS.
www.adobe.com/support/downloads/product.jsp?product=106&a...
What Nikon SLR do you have ? If it's a D80 or a D200 perhaps the Tiff file would be enough because they have a recent DSP.
You could also Artizen HDR which supports DNG :
www.supportingcomputers.net/
Fdr Tool (free) also supports DNG format :
fdrtools.com/fdrtools_basic_e.php
But I don't know If they use dcraw or not. You have to try them.
Posted 37 months ago.
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D70s - purchased before the launch of the D80
I have tried fdrtools and it is not flexible enough ... I will try artizen HDR .... merci mille fois mec - ou bien je vends ma D70s et je la remplace avec une D80 ....
Posted 37 months ago.
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gabsriel [deleted] says:
Le D80 ne fera pas bien mieux que le D70s sur ce domaine. C'est juste que le DSP est plus performant et produira donc de meilleurs tiff.
Mais l'achat du D80 ne doit pas se justifier par cela. ;-)
Tu dois d'abord trouver un moyen d'utiliser tes fichiers RAW.
Tu sais que tu peux faire la fusion HDR avec tes .nef sur toshop normalement. C'est long mais c'est le meilleur moyen pour avoir un résultat propre.
Enfin de toute façon je te conseille d'essayer artizen car il est plutôt excellent comme logiciel (même si j'adore photomatix aussi).
++
Posted 37 months ago.
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bien que PSCS ne recconnaisse pas NEF.... le D80 boitier seule c'est a 680 Euro TTC en CHine - pourquoi pas ...et enfin je reviens a toel - t'en veut
Posted 37 months ago.
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gabsriel [deleted] says:
Oh mon dieu 680 € ?... vilain, pourquoi tu me tentes...
J'ai pas les sous.
C'est gentil d'avoir proposé quand même !
Posted 37 months ago.
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@gabsriel
Je te recommend de regarder l'article suivant:
www.flickr.com/groups/fdrtools/discuss/72157594384910610/
"Integrated RAW converter DCRAW for direct import of virtually all camera RAW formats (.RAW; .CRW; .CR2; .RAF; .MRW; .NEF; .ORF; .DNG; .PEF; .X3F; .DCR; .KDC; .SRF)"
Wer lesen kann, ist bekanntermaßen klar im Vorteil ...
@TinCHINA
The preferences dialog with Tab "Raw Conversion" allows to change some of the parameters involved in the RAW import and subsequent HDRI conversion process.
Posted 37 months ago.
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gabsriel [deleted] says:
As I said befor, I use FDRTool Basic.
But the problem is that DCRaw is an awful RAW converter because it's old and not really optimized...
As TinChina said : "If I run the NEFs ( Nikon RAW) through the batch processing of the Photomatix there is often chromatic abberation around white surfaces ...."
The problem will be the same with FDR Tools because Photomatix also uses DCRaw...
Posted 37 months ago.
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