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Microstock Photography Forum - General => Software => Photoshop Discussion => Topic started by: rjmiz on May 06, 2007, 06:39

Title: Why not try HDR next time you shoot!?
Post by: rjmiz on May 06, 2007, 06:39
What is HDR? should..... I shoot HDR?....Are they any advantages to HDR?

HDR stands for "High Dynamic Imaging"
How this is accomplish is a combination of shooting technique, and software that will produce it.

How this works is: You take a minimum of 3 shots of a subject on a tripod.
One exposed perfectly (using any f stop of choice) and the other two...1 under and 1 overexposed changing speed.

an example below

(http://microstockpix.com/hdr1.jpg)

Now using software that will line up, and combine the 3 images (I use ps)
you get better shadows and highlights, a more "Dynamic" range if you will.

The image below demonstrates this better than I can explain it.
The image left is the HDR and right the perfectly exposed image that would have been produced by the camera naturally.

(http://microstockpix.com/hdr2.jpg)

A closer view below.

(http://microstockpix.com/hdr3.jpg)

Why not try it! HDR works best when the image itself displays potential dynamic range.
You can not squeeze HDR from an image that does NOT have Dynamic Range in the first place.
So HDR is not suitable for every image you take. Where you have lots of shadows, and highlights works though.
Title: Re: Why not try HDR next time you shoot!?
Post by: sim on May 06, 2007, 07:31
This was my first effort using HDR on CS2 with 7 exposures, its a bit over the top but I like the effect.
It's also possible to create the  3 to 7 images required to merge in HDR from one image by setting different exposures through RAW editing, anyone try this?(http://farm1.static.flickr.com/107/277919179_51cee94f1f.jpg?v=0)
Title: Re: Why not try HDR next time you shoot!?
Post by: Lizard on May 06, 2007, 07:59
Its possible to create HDR by changing exposure at raw file , it will lead you to a visually nice result , but with lots of noise and if you need the image for stock it will most probably be rejected at most of sites. The amount of noise at least from my experience is too much for  noise reduction to handle and the photo will have the plastic (lack of details) look. Even noise reduction with masking wont help much.
Title: Re: Why not try HDR next time you shoot!?
Post by: rjmiz on May 06, 2007, 11:38
I use RAW images for HDR....only RAW.
Reason being is JPG's are what I call "Pre-cooked" images. They are processed by the camera and contain artifacts,
PLUS I like to post process my imgaes in 16 bit. I don't get artifacts in 16 bit. Then when I do convert them to 8 bit
to make then JPG's the are almost free of any errata from processing.

Using one RAW image and making 3 or jpg's to merger HDR is a bsolutely absurd! You lose all the dynamic range!
It's silly, crazy to do that....you gain absolutely nothing, in fact you actually LOOSE alot! Try it!
Title: Re: Why not try HDR next time you shoot!?
Post by: phildate on May 06, 2007, 13:08
Miz ...please allow me to point out a few slight errors in your post:

HDR stands for "High Dynamic Range" compared to LDR "Low Dynamic Range". HDRI is "High Dynamic Range Image"

If taking three images, you probably won't get the dynamic range required with -1/0/+1. Instead you'd be better with -2/0+2 or even -3/0/+3. I prefer to take at least five exposures, sometimes seven and occasionally nine.

Most people agree that you get a much better final result if you merge your images and do the tone mapping in specialist software such as photomatix by hdrsoft. Using it's batch function on a single RAW file (I know it's sounds weird but it works) you can get an HDRI from a single RAW file. This method works much better than turning one RAW file into three differently exposed TIFFs or JPEGs and then merging those.

From what I have read on other HDR forums, the majority feel that you get the least noise by turning RAW files into TIFFS and then importing them into Photomatix. However, I feel that the ease of using RAW files directly outweighs the slight increase in noise this might result in.

Anyway, here are a couple of my HDRIs:

(http://farm1.static.flickr.com/171/473539560_905fe63135.jpg)

(http://farm1.static.flickr.com/183/482014043_15e7bb16d7.jpg)

(http://farm1.static.flickr.com/219/476212989_9d70a968c2.jpg)

I tend to try and get a realistic picture that represents what I could remember seeing with my own eyes. Over-processing can lead to a very distinctive look which, whilst neither being wrong or right, is not usually the effect I am after.
Title: Re: Why not try HDR next time you shoot!?
Post by: Clivia on May 06, 2007, 13:13
Impressive images Phil. I must give this a try.
Title: Re: Why not try HDR next time you shoot!?
Post by: Read_My_Rights on May 06, 2007, 13:26
Whenever I try to submit pictures where the dynamic range is compressed (good highlight detail AND good shadow detail) via various Raw manipulations I often get rejected at the micro stock agencies for "Flat lighting" Duhhh. Whereas the same picture with nice fat constrast and little shadow detail (all black) has a much better chance of acceptance.
Therefore my question: Is HDRI even appreciated by stock agencies?
Does success increase the less the picture looks like HDRI?
Phils skyline is in my oppinion the best example (night and dusk pictures of lightsources - cityscapes etc.) where HDRI is a must to show any detail in the shadows - however not often appreciated by the stock agencies.
Does labeling such a picture with HDRI help?

"Flat lighting" my a**. That's the point. (Sorry for the rant)
Title: Re: Why not try HDR next time you shoot!?
Post by: phildate on May 06, 2007, 18:16
If you do a search for HDR on IS you will find some images but they tend to look very natural. I haven't tried submitting any of these yet but I will let you know if I do. Part of me feels like too much work has gone in to them for them to be sold at 25c so I will probably just sell them exclusively at Fotolia and can then see a nice high price for them. Yes downloads will be fewer but at least I will feel that people have paid the right value for them.
Title: Re: Why not try HDR next time you shoot!?
Post by: Read_My_Rights on May 06, 2007, 19:34
good idea. thanks
Title: Re: Why not try HDR next time you shoot!?
Post by: Karimala on May 07, 2007, 00:36
I'd never even heard of HDR until a few weeks ago, and that's only because I stumbled upon it after installing some other automated programs.   :P  Pretty cool seeing what it does.  Thanks, guys! 
Title: Re: Why not try HDR next time you shoot!?
Post by: Grizzlybear on May 07, 2007, 02:22
If you don't have photoshop CS2 at least,you will either need to purchase a plug in,or use DRI (dynamic range Increase)

Using camera on tripod, take one shot metered for highlights,and one shot metered for shadows using spot-metering

Open both images in photoshop, add light image to dark image as a new layer

Select>color range-"highlights",check"invert" click"ok"
Add layer mask
Filter>blur>gaussian blur 250 pixels
Flatten and save

resulting in details in both shadow and highlights. Regards, grizzlybear
Title: Re: Why not try HDR next time you shoot!?
Post by: Daneel on May 07, 2007, 10:55
Hi!

Can anyone explain why HDR increases the noise in the resulting photos?

Thanks,
Michael
Title: Re: Why not try HDR next time you shoot!?
Post by: rjmiz on May 07, 2007, 10:58
Sorry not me...I have never had that problem. In fact I didn't know it even existed until a few guys mentioned it!
Title: Re: Why not try HDR next time you shoot!?
Post by: phildate on May 07, 2007, 20:21
Hi!

Can anyone explain why HDR increases the noise in the resulting photos?

Thanks,
Michael


Done properly you shouldn't experience any increase in noise.
Title: Re: Why not try HDR next time you shoot!?
Post by: Keefo on May 08, 2007, 14:54


[/quote]

Done properly you shouldn't experience any increase in noise.
[/quote

Hi Phil,

What's the proper/suggested way to do this without increasing noise? I've used Photomatix, and the tone mapped images almost always have increased noise.  I think there's even a warning or info in the help indicating that the tone mapped option usually increases noise -- the last version I used was a beta they had for download a few months ago; my HD died a couple of weeks ago, and I haven't re-installed all my apps yet (so don't have Photomatix handy).  If you have any cool tips, etc for using it, it would be great if you'd post them.  Photomatix is very cool and easy to use on the surface, but I think I'm missing out on a lot of the nuances/power of the app.

Thanks,

Kevin