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9.21.2008

HowTo: HDR Photography for free w/ Qtpfsgui

I've been playing with HDR photography as of late.

If you're not familiar with HDR photography, it is a system to capture the dynamic range of 3 or more differently exposed images into one. This means the new image contains all the good details from three images...so your highlights aren't all blown out and white, and your shadows still have detail in them instead of just being plain black. You're going to use software to merge your multiple exposures into one very detailed HDR file, usually in EXR format. These HDR files have a greater dynamic range than normal monitors or printers can output. Once you have created an HDR file, you use tonemapping to convert it down into a conventional image that our puny earthling monitors and printers can output. The tonemapping plugin or software is going to smoosh all this extra visual data you collected down into a plain old Photoshop or JPEG or other "normal" image file. This is similar to taking a very detailed audio recording and converting it into an MP3.



While playing with HDR it's fun, I'm not making my living on photography. I can't justify going out and buying Photoshop right now. I can get by between my copy of Elements and GIMP.
Last time I checked, Photoshop could create HDR, but didn't have a tonemapping plugin yet. So you'd still have to buy additional software.

I discovered a cool piece of free software (open source) that can do HDR image creation and tonemapping. It's called Qtpfsgui. You can download it here. It's cross platform, so it runs on Mac, Windows, or Linux. I'm using it under Vista Home Premium 32-bit with no problems.

The only glitch I've noticed is that sometimes the progress bars will hang for a long time, and it may seem like the application is frozen, but it's actually still running, HDR imaging is just very processor intensive. You'll notice this more on slower computers or older notebooks. It's not noticable on my Core 2 Duo desktop, but alignment and tonemapping can take several minutes on my 1GHz Pentium M notebook.


I found a very good newbie friendly guide to using Qtpfsgui to create High Dynamic Range images here: http://www.dtgeeks.com/journals/article/hdr_imaging_explained/


Give that a read and then download Qtpfsgui and give it a try.


Remember to save your HDR image as an EXR file before you move on to tonemapping. I recommend doing test tonemaps using the various presets at low resolution to figure out your settings before doing a final tonemap at high resolution.

9.19.2008

HDR Photo of Wells Street Bridge


Wells St Bridge in HDR
Originally uploaded by macrogeek

This morning I stopped on the way to work to shoot a few pics.
I explored this old wood and steel bridge near the southern end of Wells Street in Fort Wayne. I took 3 exposures using auto-bracketing at +/- 2 EV.
I was using a monopod instead of a tripod, because it's easier to pack in and out of the car for quick shots.

I assembled the HDR image using Qtpfsgui to create an EXR file and then tonemapped the HDR image down to JPEG. I used the Mantiuk preset for tonemapping.

I'm pretty happy with this result so far, except I think I need to crop it a bit. I'm probably going to reshoot it instead of doing more editing. I accidentally shot this at ISO 1600 instead of 100, and so at larger sizes the visual noise / grain is too apparent. Once I reshoot I'll post another copy.

I've only been using Qtpfsgui for about two weeks, I've assembled 4 or 5 High Dynamic Range images this way so far. This is one of the best images I've gotten thus far.

9.17.2008

Lunch w/ bugs


IMG_0381
Originally uploaded by macrogeek

I took a quick lunch today and then took a walk to the edge of a nearby field. Lots of butterflies, grasshoppers.and weird plants.

I did some shots to practice manual focusing on the dslr on the fly. I'm loving the manual control on the XTi compared to the Powershot G5 I was using before. It's tough to autofocus on a scene like this with a point and shoot...they tend to scope in and out on all the leaves. Hand focusing with the SLR lets me home in on things like moving bugs with a great amount of control.

9.16.2008

Testing the New Camera


IMG_0340
Originally uploaded by macrogeek

Well, I finally made the move to a DSLR camera.
I've been using my trusty Powershot G5 for years, and this has been a long needed upgrade. Since I got the G5, I've barely touched my film cameras since. The convenience of digital outweighed the loss of features from my trusty 35mm SLR's.

Since it's been 3 or 4 years since I've done any true photo projects other than shooting an occasional wedding, I'm going to be doing a lot more photography for myself. I'll give myself the occasional "assignment" or theme to work from, but mostly I'm just going to try to be shooting stuff that I enjoy more regularly.

I'll post whatever I find amusing and worth sharing to my Flickr account and blog the relevant images as well.

This one is one of the first daylight test shots I did with the new Rebel XTi. It was bright daylight, around 1/5000 of a sec exposure @ F5.6. This was the runoff stream from a fire hydrant being purged.

Flickr

This is a test post from flickr, a fancy photo sharing thing.

9.13.2008

Video Game Relic

I found this while I was cleaning today. It's my original one from
when I was a kid.