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HDR Processing

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#1 Clumpybug

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Posted 31 January 2013 - 06:08 PM

Hi folks,

I've got a T3 that I use to do my imaging. I want to start playing around with HDR imaging, and I have a few questions.

1. What is good software to use? I don't have the money to buy Photoshop, can I use something like Gimp? If necessary, I could spend maybe like $100 on some software, but not much more than that.

2. I use DSS to stack my images and get rid of the noise. Whenever DSS is done stacking, the image is all washed out like it always is, so I usually use image editing software that came with my Canon T3 to adjust the color/contrast/brightness, etc. Based on what I've read, when doing HDR processing, pretty much everything except the exposure needs to be the same between the images. Do I need to keep a record of exactly what changes I made to, say, the dark, underexposed image and then apply those changes exactly the same to the bright, overexposed image before doing the HDR processing?

Thanks!

#2 Tonk

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Posted 01 February 2013 - 05:32 AM

Not an answer to the HDR part - but a note on your DSS comment

, the image is all washed out like it always is


Thats usually only the image the DSS shows in the review panel - as its does a guessed stretch to show you something. The image saved under "Save Picture" (lower left panel) is different. I recommend that you turn off the option to apply image processing settings when you save.

DSS does a linear conversion of the RAW and not the (approx) logarithmic conversions that cameras to when converting to say JPEG. This is absolutely correct for AP. So it does mean that you have to apply your own transform in some other software. I always us the Digital Development Processing transform in Images Plus - there are versions of this on most astro image processing software. This is a very good initial stretch

#3 Tonk

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Posted 01 February 2013 - 05:34 AM

This may help. I use Autopano for HDR processing. Not sure if this is in buget for you

#4 Ptarmigan

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Posted 01 February 2013 - 09:01 PM

I use Luminance HDR for HDR processing. It is free.
http://qtpfsgui.sourceforge.net/

#5 avarakin

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Posted 02 February 2013 - 08:50 PM

HDR for astro imaging is a pretty advanced subject and needed only for very few targets like M42. Most folks do artificial "HDR" for M42 in Photoshop.
Before doing HDR I suggest to master the basic processing skills. The software for this is:
1. Fitswork - free and pretty good, see tutorial in my signature.
2. Photoshop CS2 is currently available as a free download from Adobe. How legal to download and use it, I dont know. Use your own judgment. For fear of being banned from the forum, I am not posting a link, but a quick google will bring you to the right place.

Alex

#6 Clumpybug

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Posted 04 February 2013 - 02:17 PM

Cool. Thanks for the help, folks!

#7 lakeorion

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Posted 06 February 2013 - 09:42 PM

I've used Picturenaut for (daylight) skyscapes and clouds. Free and works pretty well.

#8 Mike Unsold

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Posted 10 February 2013 - 10:42 AM

Not an answer to the HDR part - but a note on your DSS comment

, the image is all washed out like it always is


Thats usually only the image the DSS shows in the review panel - as its does a guessed stretch to show you something. The image saved under "Save Picture" (lower left panel) is different. I recommend that you turn off the option to apply image processing settings when you save.

DSS does a linear conversion of the RAW and not the (approx) logarithmic conversions that cameras to when converting to say JPEG. This is absolutely correct for AP. So it does mean that you have to apply your own transform in some other software. I always us the Digital Development Processing transform in Images Plus - there are versions of this on most astro image processing software. This is a very good initial stretch


Digital development in ImagesPlus 4 and 5 is a HDR stretch as shown by http://www.mlunsold....P4/DDP/DDP.html

Mike






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