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r3g
06-09-2007, 03:55 AM
Ok so im trying my hand at HDR. Ive taken a single raw images and broken in up into 7 different exposures w/ Lightroom and saved them as .TIF shown in the picture below.

http://img513.imageshack.us/img513/9532/17828674jg6.jpg


But whenever i try to merge them into an HDR with CS2 i get this message.

http://img186.imageshack.us/img186/7236/errorfy0.jpg



Help. :(

Norm in Fujino
06-09-2007, 09:32 AM
Try Photomatix?

zmikers
06-09-2007, 10:06 AM
Try Photomatix?


Agreed! And check out this tutorial http://stuckincustoms.com/?p=548!

Chrisku13
06-09-2007, 05:19 PM
My advice would be to use different exposures. It looks as though you've simply brightened and darkened the main RAW photo (which you essentially did), and that doesn't increase your dynamic range. I know there are ways to do it with one RAW, but not sure as to how effective it would be.

D Thompson
06-09-2007, 07:26 PM
I seem to remember reading somewhere that if you are using a single RAW file and converting with different exposures that you have to go into the exif and strip it to "fool" CS2 into thinking it's actually shot that way.

AdamW
06-09-2007, 07:39 PM
It looks as though you've simply brightened and darkened the main RAW photo (which you essentially did), and that doesn't increase your dynamic range.

I'm pretty sure that you're mistaken. RAW does contain a wider range of dynamic information than jpg. That's one of the reasons people shoot RAW.

fionndruinne
06-09-2007, 07:52 PM
Out of curiosity, can you compile an HDR image in Photomatix, save it, and open and tone-map it in CS2? That would get around the watermarks that Photomatix puts into tone-mapped images using details enhancer (generally the most effective of the two tools in Photomatix).

zmikers
06-09-2007, 08:03 PM
I'm pretty sure that you're mistaken. RAW does contain a wider range of dynamic information than jpg. That's one of the reasons people shoot RAW.

Using one image and simply lightening and darkening it might work but it definitely is not as effective as using three or more different images. I have posted this in another thread so sorry for the double post. If your shadows are black and or your highlights are blown out, the details in either cannot be recovered as the image has no information in those areas to be recovered. This is the purpose of using HDR. Using different images over and under exposed can save the details in the shadows and highlights and "properly expose" all areas into one photo.

AdamW
06-09-2007, 08:58 PM
Using one image and simply lightening and darkening it might work but it definitely is not as effective as using three or more different images.

I agree that multiple exposures works better, and you explain why very nicely in the other thread. But using different jpgs from a single RAW should work also (just not as effectively.)

And manipulating a RAW file isn't just "simply lightening and darkening." The RAW image contains the data to define a much wider dynamic range than can be displayed on a monitor or in a print. The data is there, what you do in PP is decide which subset of that data to display.

I'd also like to know how to get CS3 to do this with RAW.

zmikers
06-09-2007, 09:07 PM
LOL Fair enough. I know using RAW is better than jpeg, maybe I was a bit to nonchalant about it.:p

AdamW
06-09-2007, 09:14 PM
Well, here's hoping that someone can answer the OP. Cause I've had the experience where I've taken a shot, come home and opened it on my computer, and realizing I should have taken multiple exposures and combined them, tried to do it with a single RAW file and gotten the same error message as Reg. I'd even appreciate someone explaining how to do it manually in Photoshop.

Norm in Fujino
06-09-2007, 09:34 PM
I'm copying this from a similar thread on another forum (http://www.fourthirdsphoto.com/vbb/showthread.php?t=14023):

"First thing to remember is that Photoshop reverses the order of rank, so that
in our example image set above we need to assign the most negative EV to
the least dense image and the most positive EV to the most dense image. This
will avoid an error message which confusingly tells us; "There is not enough
dynamic range in these photos to construct a useful HDR image". There are a
few other things we must do if we want to avoid Photoshop confusing our
attempts at processing with this tool. The rules for HDR that I have observed
can be summarized as follows:


* For Image sets of all sizes, one image will by default have an EV of 0.
Plan for this when using the 'Manually Set EV' window.
* For image sets of 3 or 4 images one image (the lowest density image) will
by default have a negative EV; plan for this when assigning EVs.
* The remaining one or two images will by default have positive EVs. NB it
is possible that Photoshop will assign zero to more than one image. Since this
would be a nonsense, if and when this happens it is time to re evaluate your
selection of EVs; more on this later.
* By default, image sets of 5 or 6 images have the 2 least dense images
assigned negative EVs, and again the next image will by default have a zero
EV and the remaining 2 or 3 images should be positive. Plan for this when
Manually Setting EVs.
* Image sets of 7 or 8 images by default must have the three least dense
images given negative EVs, the forth image set at zero and the remaining 3 or
4 images will need positive EVs.
* Beyond 8 images has not been tested by me and I doubt there will be
many circumstances where 9++ image sets will be used. However, I suspect
that the same pattern of default requirements having some negative EVs, one
zero and the remainder positive would apply"

AdamW
06-09-2007, 09:37 PM
Thanks, Norm!!