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Damo 5D
27-12-2010, 9:39pm
I dunno, is it just me, or does anyone else find them not that appealing ?

I always thought it was High Dynamic Range, producing a final image that is a result of merging several frames at different exposures to get a balanced image that covers more stops than a sensor or film can record. I hadn't seen too many images of this type before getting on here, and to me, most of them just look like highly saturated images with unrealistic colour. Some get the range of exposure, but still have way too much colour, and others, well, just colour and nothing else, still black in the shadows and over exposed in the high-lights.

So what is it really supposed to be ?
(this is a serious question, not a dig, so please be nice)

Speedway
27-12-2010, 10:19pm
Good ones you'd never know. Most look like you describe to me too.
Keith.

dbax
28-12-2010, 10:42am
many threads on this topic and the consensus seems to be you either love them or hate them. I reckon they're fine when used in an arty fashion, not so fine when used to represent nature etc. That being said HDR, when well done, can result in some stunning images. I think some that are a blend of the mid range image and the HDR image often give the best results, and subtlety is the key.

Xenedis
28-12-2010, 10:53am
HDR is a technique over-used by many people (especially beginners with the technique), whose result is the turning of an otherwise decent photo into a horribly over-processed, illustration-looking, halated, over-saturated piece of rubbish that screams "I am an amateurish, over-processed HDR image".

Good HDR images are those in which you cannot easily tell that HDR techniques have been used.

If the effect dominates the actual subject or concept, then the plot has been lost.

Less is truly more.

kiwi
28-12-2010, 12:31pm
HDR stands for Hard to Do Right

ameerat42
28-12-2010, 1:14pm
Right, Damo. Also, look at the links in this thread from the other day. Am.
http://www.ausphotography.net.au/forum/showthread.php?74379-A-treatise-on-HDR-and-associated-concepts

Mr Felix
24-01-2011, 6:00pm
OK, I'm going to enter into the question.

I have a power point thing and one of the shots caught my attention to how it looks.

I asked someone who said it was touched up and was an HDR image. I asked if that was like a bracketed shot and they said no. Because this shot has moving things in it, making/taking bracketed shots would not be possible. Instead it is HDR.

Yet, reading what is written here, I am understanding you still need to take multiple shots. Kinda difficult if things are moving.

I shall include the picture as soon as I can.

For the sake of my curiosity - yeah, cats, curiosity, Mr Felix... What can I say? - I'm interested in how you do it with ONE shot.

I'm guessing you can. I'll shut up now until I get the actual picture.

kiwi
24-01-2011, 7:10pm
Take the one photo into Photoshop, adjust exposure by a stop over, a stop under then merge them as a HDR

Mr Felix
24-01-2011, 7:16pm
kiwi,

OK.... (I'd better reitterate, there is a village somewhere missing their idoit) How do I do that?

Though I have photoshop, I have't used that function/feature of it.

Sorry.

ricktas
24-01-2011, 7:21pm
File> Automate > Merge to HDR

(depending on version of photoshop)

William
24-01-2011, 7:50pm
Mr Felix, You have to create an image for a HDR from one file , Preferably from one RAW file , The most common is to get the file and Change the exposure to - 2, 0 , +2 , So now you have 3 images of different exposures , Then load as Rick says into photoshop , File > Automate > Merge to HDR , You can use use any combination of odd numbers , 3,5,7,9 to merge together to get what they call a Pseudo HDR , The real one is done in Camera changing the shutter speed up and down to give you the different exposures to create a true HDR

kiwi
24-01-2011, 7:57pm
Sorry, yip, assuming you know how to create three file with different exposures ?

Mr Felix
24-01-2011, 7:59pm
But making 3 files with three different exposures is bracketed metering - right?

ricktas
24-01-2011, 8:04pm
But making 3 files with three different exposures is bracketed metering - right?

Yes, and then merging those three files using HDR techniques is called HDR!

William
24-01-2011, 8:04pm
Yep , Three different exposures of the same image , Basically blended together,( Sorry Rick you beat me to it )

Xenedis
24-01-2011, 8:07pm
But making 3 files with three different exposures is bracketed metering - right?

Multiple exposures of the same scene (taken at different shutter speeds) can be blended/merged two ways:


manually, by brushing in details from one exposure onto another using layer masks; or
somewhat automatically using HDR merging techniques in the form of dedicated software (eg, Photomatix Pro) or Photoshop's 'merge to HDR' feature.

Longshots
24-01-2011, 9:16pm
well yes and no - the typical sensor on a good DSLR has a fairly good dynamic range, and its quite possible to "draw the information" out of a raw file, to imitate a bracketed image. So in some situations a single raw image can produce not just say 3 differently processed images from the single image, but depending on specific adjustments quite a large number of images - all different "exposures" from the one single exposure (all done in Adobe Camera Raw or similar Raw processor).

Now if you want to then look at Medium format sensors, the dynamic range is quite considerably extended making HDR (which stands for High Dynamic Range) techniques almost pointless. I was using the latest Hasselblad HD40 recently and literally blown away by the amount of information captured, that can then be "accessed" in the Raw conversion processing.

And it gets better because the Red Camera system and their sensors are simply stunning, with a dynamic range of their sensors that have to be seen to believe. What may in Raw look like a desperately over or under exposed image, is simply brimming with such a large range of information, that it makes you wonder if we'll be worrying about exposure in five years from now.

A link for the Red Camera System:
http://www.red.com/

and just in case - a link for the Blad systems:
http://www.hasselblad.com.au/hb/

kiwi
24-01-2011, 9:20pm
Interesting, thanks William, Ive always thought that a topline dslr has about 7 stops dr ? About right ?

Xenedis
24-01-2011, 9:27pm
Personally I would prefer to bracket than try and push exposure in a single raw image, especially as pushing exposure on under-exposed images (even with whatever latitude raw may give) can introduce noise.

I am new to HDR imaging, and of my recent images, I used no less than four exposures, and for my QVB interiors, I used seven images (-3EV to +3EV).

Bracketing doesn't require a great deal more effort at the capture phase, and I'd rather have the most options in the way of the best input I can provide in the form of a wide range of exposures.

Mr Felix
25-01-2011, 1:35pm
Ok found the image.

This is it.

Not mine, but I'd be interested if anyone can tell me "how" it is/was taken/made.

* I have removed this photo. DO NOT put photos on Ausphotography that you have not taken. You are breaching copyright by doing so : Admin *

William
25-01-2011, 1:43pm
Mr Felix, Here's an example of HDR from one RAW file that I did of mine , It has movement in it , The Waves !!

Mr Felix
25-01-2011, 1:52pm
Thanks William,

But is the one I submitted qualify as HDR?

Just the smoke seems too "clear" to be a normal picture.

William
25-01-2011, 2:02pm
Yep , I'd say by the look of it , It's a single RAW image HDR , Mr Felix , Go to photomatix web site you can download a free trial version , Just has water marks on the images , Or buy for $90 , You just have to load one RAW image in , Use the default settings for processing and you'll get what they call a pseudo HDR from a Single file , Which works if there is a heap of movement , Thats the easiest way :)

Mr Felix
25-01-2011, 3:06pm
Thanks.

:th3:

I shall also have to find time and sit down with fotoshop and learn how to do all those/these tricks.

Othrelos
25-01-2011, 3:52pm
"HDR stands for Hard to Do Right "

don't you mean Hard to Do Tastefully?

I actually blend my HDR images by hand, now that I have a graphics tablet (wacom intuos4) I can do it significantly faster and with far more control than what was previously possible.

Mr Felix
25-01-2011, 7:33pm
OK, next question.

My 330D made .CRW files.

Now with the 550D and I take RAW images, I get .CR2 files.

Adobe says it can't load them.

Short of re-naming them - a typical windozxe fixall - what do I need to do to get Adobe to load the files?

William
25-01-2011, 8:00pm
Into what editing program ?

Mr Felix
26-01-2011, 7:01pm
PhotoShop cs3

William
26-01-2011, 7:08pm
You'l probably need to update to CS5 for it to read .CR2 files from a 550D , Each new version of PS includes updates of new Cameras , Dont think the 550D was out when CS3 was released

Mr Felix
26-01-2011, 7:11pm
Ok, next question.

For the sake of learning, while at Parramatta this morning, though I don't do raw files because of the problem mentioned above, I bracketed a shot of some balloons. PhotoShop didn't mind loading the three pictures with the HDR thingy/function.

Ok, it did some things itself but then what happens?

I tryied to save the picture but couldn't save as JPG.

Saved it as the PhotoShop format and tried to look at it.

It is HUGE! And it won't load. 23MEG I think.

I am trying to get my head around the process, but if someone wouldn't mind giving me a bit of help.

ricktas
26-01-2011, 7:21pm
HDR are 32 bit images. JPG are 8 Bit. If you want to save the resultant photo, go to Image > Mode > and change it to 8 bits/channel and then you can save it as JPG

Mr Felix
26-01-2011, 8:06pm
As you can see, I am not good with the programs features.

alextdel
19-02-2011, 12:49pm
This thread has clarified a few things about HDR. Thanks to all.