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HDR Workflow – Should you convert to Jpegs before processing

September 19, 2011 / Bruce posted in Announcements, Learning, Photomatix / No Comments

I’ve heard it said a number of times, but I just don’t understand it. Why would you do this? What I’m referring to is converting your images to jpegs before processing them for HDR in Photomatix. I’ve had a number of people tell me that you should convert to jpegs prior to merging to HDR in Photomatix because you’ll get a better result and because the software converts to jpeg before processing anyway! Let me tell you here and now – this is hogwash!! The answer is “NO”! You should not convert from RAW or Tiffs to jpegs prior to processing the HDR, regardless of what you may have read or been told, you should not do this!

In a recent conversation with an individual from Canada I was told I should try the above because that is what “Trey Ratcliff” recommends and he has been doing HDR for years, therefore he should know what he is talking about. My response was simply “that doesn’t make sense. Why would you ever convert to a format that throws away a significant amount of data before making use of the data? I’ve always used the Tiff file format and have gotten great results in my HDR images (see the image above).”

Well my friend from Canada posed the question to the makers of Photomatix (HDRSoft) and received a definitive answer from Geraldine of the Photomatix Engineering Team that should put an end to this nonsense:

“Photomatix does NOT convert the images you are importing to JPEG for internal processing, and never did it. It would not make any sense to do this…

The only moment Photomatix converts to JPEG is when you want to save the image created by Photomatix and choose to save it as JPEG. This applies to an image created by Photomatix, not to an image you imported.

Regarding whether it is better to convert RAWs in Photoshop before processing in Photomatix, you will find a detailed discussion on this on the FAQ here:
www.hdrsoft.com/support/faq_photomatix.html#process_raw

However, converting TIFF files to JPEGs in Photoshop before processing in Photomatix is a bad idea, given the loss of quality due to the conversion to JPEG.”

Please take note of that last sentence again “converting TIFF files to JPEGs in Photoshop before processing in Photomatix is a BAD (emphasis added) idea…”.

Thanks Geraldine!

If you shot your image sequence as jpeg files, then you should process them as jpeg files because you’ve already thrown away 1/3 to 1/2 of the available data by shooting in jpeg format. However, if you shot your image sequence in RAW or Tiff, then it is recommended that you process the HDR sequence as a series of Tiff files. Why not RAW files, please refer to the link above for information on RAW processing in photomatix. In short, yes you can and Photomatix does support it, however you might get better results if you convert the RAW files to Tiffs using Photoshop, Lightroom, Aperture, or other more sophisticated RAW processor.

With that said, I would ask that you share this post with everyone you know – tweet it, retweet it, share it on facebook, and any other social media site you might participate in, and let’s put an end to the myth that “you should convert to jpegs prior to HDR processing”!

Using All Available Detail

May 31, 2011 / Bruce posted in Learning / No Comments

Sometimes to make the shot work, you need to have access to all the available detail that the camera can capture. If you are shooting in JPG mode, then you are throwing away the available detail and letting the camera decide what to keep and what to use. In some cases this might be okay, particularly if all you want is snap-shot type of quality from your images. However, for those of use who want more from our images, this is not okay and is why I strongly suggest you shoot in RAW mode rather than JPG mode.

RAW mode can capture a significant amount of image detail that you might not see. For example, here’s an image I shot recently inside the Burlington Railway Presidents car in the dining area. It’s a nice image that was exposed for the light inside the car. This means that the details in the windows is lost – or is it?

I processed the image in Lightroom 3 getting the details of the room just right. Even though this is a nice image as is, it feels a little closed off to me. Not all that inviting. So I created a “virtual” copy of the image in Lightroom, and with this copy I used the exposure slider to underexpose the image by almost 4 stops, which gave me the following image.

As you can see, there was significant detail that the camera was able to capture in what appeared to be overexposed or lost information in the first image above. This is the value of a RAW image. Sometimes you can pull back the detail from the overexposed or underexposed areas of the image. Of course the amount of detail you can pull out of these areas depends on the original exposure and the lighting of the scene. In other words, don’t expect this to work in every situation. It may work, but to vary degrees of success.

In this case, I was lucky enough to have about 4 stops of information/detail available. For this image, I think the view in the window areas is nice and I want to include this detail in the original shot above. Since I now have the original, and the copy I made in Lightroom to which I adjusted the exposure for the window detail, I can now open these two images as layers in Photoshop and blend the two images together.

Once in Photoshop, I made sure the underexposed image was at the bottom of my layer stack, and the original image at the top. I then added a layer mask to the original image and painted over the windows with a black brush (black allows the layer below to show through, white blocks the layer below). Once I had painted over each of the windows with my black brush, I had the following final image which feels more open and airy and inviting.

This is one of those images that some people will mistake for an HDR image because you can get the same result through HDR processing. However, in this case, the light was low inside the train car and space did not allow for a tripod. Hand holding was the only option, and to shoot 5 or more frames in HDR in low light would have been extremely difficult to get a good sharp result. But, as you can see, shooting the image in RAW and a single exposure gave me the same kind of results as an HDR image without losing sharpness due to camera shake during slow exposure times needed in the HDR sequence.

If you’re wishing you had more detail in the sky or in a window or wherever in your scene, don’t dismiss the potential detail that may be there if you shot the image in RAW mode. If you didn’t shoot it in RAW mode, then you should be asking yourself why?

HDR without the “look”?

January 31, 2011 / Bruce posted in Informative, Thoughts / 1 Comment

Yes, I seem to be harping on this issue some, but I feel it is an important issue. Although you can achieve a number of different looks with HDR photography from very natural to surreal and beyond, the technique was developed to allow photographers to capture and render a scene that couldn’t be captured before due to limitations within the camera. However, the technique also opened up the ability to apply a creative and artistic twist to the image that was very difficult to do otherwise.

I tend to prefer a more realistic look in my HDR images. Realistic to the point that the only way you would know HDR was used in the creation of the image is if 1) you are a photographer and recognize the dynamic range of the image is more than a single frame can capture, or 2) I tell you it is an HDR image. My preference is just that, my preference or stylistic choice. It is what I feel presents the image in a way that is representative of my vision when I captured the image on my camera.

I could have presented this image in any number of stylistic possibilities that the HDR technique opens up, but this is the presentation I chose for this image because it matches my vision.

Because HDR photography has many different “looks”, it would be improper to categorize HDR as “a” look, which is what people tend to want to do. My argument is simple, HDR is not a single look, but many looks! So please don’t say an image has or does not have the “HDR Look”. Doing so demonstrates a lack of understanding in relation to HDR photography. Enjoy the image the way the photographer chose to present it, and not critique it for the technique that was used to create the image. This is what it is all about – really!

What’s in Your Library?

December 2, 2010 / Bruce posted in Learning / No Comments

Yes, I read a lot. For me, learning is a continual process. I have a number of photography books in my library that I refer to often. I heard it said that the day you stop learning is the day you die! Well I don’t plan on dying anytime soon, so my library of photography books (as well as other subjects I’m interested in) will continue to grow. Here is a picture of some of the photography books I have. I did not include the how-to specifics on Photoshop and Lightroom that I have. (click the image for a larger view)

My four favorites are the ones in front, primarily because I love landscape photography and HDRi! The other book “Vision & Voice” by David Duchemin has got to be my all time favorite book. David takes you through his process of expressing his vision & voice through photography using Adobe Lightroom. It is a powerful book and has helped me to begin to understand the process of refining my vision. This vision is the one that caused me to take the image to begin with. The voice is how to express the story you want the image to project. Well worth the money I spent to get this book. If you are looking to add a book to your library this Christmas, this is the book I would recommend.

As for HDRi photography, I absolutely love Jack Howard’s approach in “Practical HDRi”. As the name suggests, it is a very practical approach to learning the art of HDRi photography. This would be my first recommendation of books on HDRi photography. Jack also gives a couple of bonuses in his book, but I’m not going to tell you what they are, you’ll have to get the book for that!

I like a wide variety in my library (as you can see in the image above) and I don’t think any library on photography would be complete without Brian Peterson. You just have to have at least one of his books. Me, I have three and I also subscribe to his emails from the Perfect Picture School of Photography (PPSOP). There are lots of video tutorials he does and sends them out to his subscribers.

Anyway, if you can’t tell, I think education and continual learning are important no matter what you are interested in, and the more you invest in your learning, the better off you’ll be! So do yourself a favor this holiday season and invest in your education, be it through books, classes, or workshops!

Photomatix Pro 4 – Short Review

October 20, 2010 / Bruce posted in Impressions, Photomatix, Reviews / No Comments

Photomatix Pro version 4 has been available for about a month now, and I’ve been using it since it was in beta. Yes, even the beta version with all it’s bugs and quirks was better than version 3, and I dare say better than most of the competitors products. I have looked at and used a few of the competitors products, but my preference is still Photomatix. It is hands down the best HDR tool available and is the choice for most professional photographers.

I have written a couple of tutorial/references for Photomatix version 3 which are available on this site…

Exposure Fusion in Photomatix – A Reference

Tone Mapping in Photomatix – A Reference

Most of what is written in these references is still valid and applicable to version 4 as the basic controls did not change. However, there are a few new features worthy of mention.

Selective deghosting. ghosting occurs due to movement in the scene, either in the background such a leaves blowing in the wind, or in the scene itself such as people moving through the scene. In version 3, the automatic deghosting worked pretty well, but in some cases it would not remove all the ghosting from the scene. In version 4, the selective deghosting allows you to select the areas of concern and specify which image of the set to use for the deghosting. The results are well worth the upgrade. Oh, did I mention that the upgrade is free for owners of Photomatix Pro version 3! Well it is!
Improved noise reduction. one of the facts of life in HDR Photography is noise. When combining multiple images together noise becomes a factor especially in the darker images. Photomatix version 4 now addresses the noise issue upfront by applying noise reduction technology to the source images so that the resultant image has less noise. Very cool when you think about the time savings realized.
Thumbnail previews! this is one of my favorite additions to the new version. You can now scroll through the thumbnail previews and select the one that closely resembles the look you are after. It is then a short set of tweaking the settings for just the right look and your done. Also, if you create a preset and save it, Photomatix creates a thumbnail view of your preset for the next time you use the program. Very cool!

These are the most notable additions to the new version, but that is not all. There have also been some adjustments to existing functionality and additional improvements added. They even increased the speed which is a very big deal that we are all happy with. Creating HDR imagery takes time and any reduction in the time to create the image means more time available to shoot more images! Yea!

Here’s a basic summary of Photomatix Pro 4 features: Tone mapping and exposure fusion methods are now accessible from the same area allowing you to switch back and forth before deciding on which method is best for your image, there are two methods available for tone mapping and six methods for exposure blending, semi-manual or automatic deghosting, 16 bit support, tone mapping a single 8 bit image, alignment tool, batch processing, and full support for both Mac and Windows environments.

If you are contemplating HDR photography, or you are into HDR photography, I highly recommend getting Photomatix Pro version 4. If you are purchasing for the first time use code “HDRPhotoZone” to receive a 15% discount off the already amazing price of just $99. If you already have version 3, what are you waiting for? Here’s the link: Photomatix Pro 4

Exposure Fusion in Photomatix – A Reference

August 12, 2010 / Bruce posted in Photomatix, Tutorial / 4 Comments

If you are looking for a good way combine multiple exposures to achieve dynamic range in a natural or realistic maner, you should give the exposure fusion method a try. Although you can achieve realistic looking images using the tone mapping options, exposure fusion will give very good results with a lot less work on your part. The exception is that if you have moving objects in your scene, you might want to use the tone mapping option to take advantage of the deghosting feature. Additionally, for really high dynamic range images, tone mapping will be the better option as exposure fusion doesn’t handle really high dynamic range very well – i.e. it won’t look natural.

The first options you have within exposure fusion allows you to select how the exposure fusion should work or which method you want to use. There are five options.

Average will average the exposures together based on the available information in the exposures. You do not have any options available to you with this method and I find it rare that you would ever want to use it. After all, when would you want a straight average of anything?

Highlights & Shadows – Auto looks at the highlights and shadow information in each of the exposures and blends these exposures together to achieve a natural and realistic look. Again, there are no adjustments that you can make with this method. Although the results look pretty good, I would rather have some control over the outcome rather than letting the computer decide what the final image should look like. So again, it is rare that I would use this method.

Highlights & Shadows – 2 Images allows you to select which two images of your set to use then applies the “auto” method to blend these images together for the final result. There are no adjustments available other than selecting which two images to use. This method may get you the result you’re looking for, but if you want to tweak your image, this is not the method to use.

Highlights & Shadows – Intensive applies a rather aggressive blending or fusing method that often causes banding or an unnatural look in clouds. Luckily, this option gives us three sliders for some control of the final look. Of the three sliders, Radius has the most effect on the image because it sets the weighting amount to use when fusing the images together. The higher the number the less banding and haloing you will see, but it takes significantly longer to process the image. If you use this method, and you should try it, adjust the radius first to dail in the overall look of your image, then adjust the local contrast using the Strength slider. Negative numbers on the strength slider will flatten your image by removing contrast and positive numbers will punch up the contrast and increase depth. Lastly adjust Color Saturation to your desired amount. Just remember, too much of a good thing is not good – make small adjustments and maybe don’t adjust the color at all within photomatix. Save the color adjustments for photoshop, lightroom, or other photo editing software used in your post processing work flow.

Highlights & Shadows – Adjust applies the same blending or fusing of the auto method, but allows you to make a number of adjustments to the final image. This is the default method for exposure fusion and is the method you will end up using for more than 90% of your images for which you use exposure fusion.

At left you see the adjustment panel for the adjust method. I will go through each of these controls in the order in which you should use them (which is not the order – top to bottom – they are presented). Although I am suggesting a certain order for using these controls which I hope will make sense, you can use them in any order you choose. So let’s get started.

Blending Point – this controls the weighting given to the under exposed images versus the over exposed images. If you want the fusion to use more information from the underexposed images, move this slider to the left or into the negative numbers. Likewise, move the slider to the right or into the positive numbers if you want to include more information from the over exposed images. Another way to think of this control is to think of it as an exposure control – negative numbers will under expose where positive numbers will over expose your image.

Accentuation – this is the same as the Strength slider in the intensive method. It controls local contrast. Moving the slider to the left into negative numbers will remove contrast and flatten the look of your image. Moving the slider to the right into the positive numbers will punch up the contrast and increase depth.

Shadows – this controls the brightness of the shadow areas without affecting the highlights. If the shadow areas in your image are too dark, move this slider to the right to brighten up the shadows. Again, remember a little adjustment goes a long ways. Don’t over do it.

White Clip – Think of this as a fine tune adjustment for contrast in the highlight regions of your image. Increasing this slider – moving it to the right – will increase contrast in the image but does it at the expense of detail in the highlights. You will lose detail in the highlight regions when increasing the white clip slider.

Black Clip – works the same way as the white clip, just does it’s work in the shadow regions of your image. Increasing this slider – moving it to the right – will increase contrast in the image at the expense of detail in the shadow regions, i.e. you will lose detail in the shadows when increasing this slider.

Midtone – controls the overall brightness of the image but also affects contrast. Moving the slider to the left reduces brightness in the image and increases contrast. Moving the slider to the right will brighten the image but reduce overall contrast. To dial in just the right look may require multiple adjustments to Accentuation, White & Black Clip, and Midtone sliders. Just make small adjustments as you dial in the right look.

Color Saturation – does just what the name suggests, it adjusts the saturation of the color in the image. This is a global control and as such you may want to consider making color adjustments in photoshop, lightroom, or other photo editing software that is designed specifically to work with color. I have at times increased this slider to add just a little more color to my image, but I will always fine tune the color in other photo editing software.

360 degree image – removes the seam from a 360 degree panorama. This is another option that is probably better left to another application that is designed specifically for processing panoramas.

Presets – allows you to select and/or save presets for use. If you have dialed in a specific look that you like, save it as a preset. Then on the next image all you need to do is select your preset and your done!

Again, remember that when you click on the process button, you are not done. Your image is now at that RAW stage and additional post processing is needed to finish up and give the image it’s final look.

That’s all! Hope you find this reference of use.

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