A Quick Play With HDR

Following some discussion in the camera club I have had a quick look again at HDR, and it is a very quick look. I had used HDR software in the past but I have had several PC incarnations since then and it was no longer installed.

I have just installed Enfuse and used the EnfuseGUI which can create HDR images and, I believe, also do focus stacking. It is open source and so costs nothing. I believe it can also be used as a plugin for Photoshop, Lightroom and Aperture. In that case you use Enfuse and a plugin.

I have put next to no effort into this and I think the results are quite presentable. Because it was so easy I thought I would share it. With a bit of experience who knows what is possible?

The image I have used is a view of the cricket pavilion in Robert’s Park.

Straight from RAW file

The image above is taken from the RAW file. Looking at the settings it looks as though I had very slightly tweaked it – brightened slightly, the contrast increased and the shadows darkened. The sky is a bit (?) nondescript to say the least.

After installing the software I went back to the original RAW file and saved 3 JPEG images from it after changing just the exposure.

Darkened

With this one I darkened the RAW image several f stops and then saved as a JPEG. The sky looks reasonable but everything else is too dark.

As is

This one is saved as a JPEG from the RAW file with next to no adjustments.

Brightened

This one is after brightening the RAW file and saving the resultant JPEG. You can now see a bit of detail on the scoreboard.

HDRd

And the last one is processed through the HDR software accepting the default settings.

I then went through each image and changed the size to 1200×757 and saved at 95% quality. I think the processed one looks quite good. It doesn’t glare at you and was very easy to do. If I was serious about it I should have taken 3 or 5 photos of the scene at different exposures and then worked with loss-less image file formats throughout until the final save as JPEG, but as I said, this was a quick trial and I am quite pleased with the result.

The reason for going back to the RAW file and changing the exposure is that there is much more data in the RAW file. Darkening the RAW file brings detail out of the clouds whereas if I had used a single JPEG the sky might have already been “blown out” – white, with no way of bringing out the contrast between some of the areas as it is darkened. Similarly with the dark areas. Also the JPEG file format looses data and the image can deteriorate every time it is saved.

For an image to render what looks like a wide dynamic range it must darken some areas and lighten others but transition carefully between them. This can cause one of the things I don’t like about some processed images. You can get halos around dark edges. You can often see this along a roof with the sky above. ┬áTo maintain the HDR effect the contrast between the roof edge and the sky is kept high in that area but then as you get further into the sky the sky must be darkened to bring out the clouds. This often means that there is a bright halo around the roof. This is one reason why it may be better, in some cases, to do the work by hand.

My camera backpack

When I started off with my Canon 1000D Digital SLR back at Christmas 2009 I bought a small bag that carried the camera, spare battery and lens brush. The following Christmas I got the Canon EF-S 55-250mm lens which still fitted in the bag comfortably.

In 2011 I bought the Sigma 150-500mm lens. For a while I carried this around in the box-like case it came with but this meant that I did not have a way of protecting/carrying it when it was on the camera. I therefore bought a big shoulder bag but I found that this was uncomfortable on long walks even though it had straps to carry it on my back.

I therefore spent a while looking at alternatives and finally bought a Lowepro Flipside 400 AW backpack. I have been very pleased with this but it was a while before I realised that one of the reasons for the waist strap was to allow you to take the straps off your shoulder and swing the bag round to the front, open it and swap lenses etc. without having to take the bag off and put it down somewhere.

I now use it to carry everything other than my second tripod.

The only downside I can think of is that the tripod fits to the front of the bag and the top strap tends to pull it against the bag and squash things up a bit. If the strap is not tight, or if I use only the middle strap then the tripod leans back and spoils the balance when walking. It might be better if the tripod was fitted to the side of the bag so that the weight is closer to your back.

So, either inside this, Lowepro Flipside 400 AW Backpack

or strapped to it, I fit all this –

Camera

replaced with a Canon EOS 7D in 2012

Canon 50mm 1.8 lens

Canon 18-55mm lens

with Hoya 58mm UV Filter fitted to protect the lens.

Canon 55-250mm lens

with Hoya 58mm UV Filter fitted to protect the lens.
and Canon ET-60 Lens Hood
Sigma 150-500mm

This filter is not normally fitted due to increased chance of “banding” on out-of-focus lines. Perhaps this is as a result of going for a cheap one. I may post about this sometime. I have noticed it on many wildlife photos on flickr and it is certainly not limited to this lens. The lens hood is deep enough to protect the lens from accidental touching. Maybe I will get the Sigma 86mm filter sometime.

Polaroid Auto Focus Macro Extension Tubes

Giottos Tripod
fitted with Giottos Ball Head

Gorillapod
with Ball Head
Spudz Lens Cloth

Extreme Pro 8GB SD Card (read this post about the card)

SD card reader

Lens brush

Air Blower

LCD Display Wireless Remote
(mine is not on Amazon now but this looks like an update to it)

Hoya 58mm Circular Polarizing Filter

Spare battery

Spare battery for the remote release transmitter – bog standard AAA batteries.
Spare battery for the remote release receiver

Olympus voice recorder
– to record sighting and shooting notes. I have yet to use it for that purpose. This is a link to a similar one.

Nikon binoculars

Insect Repellent
– essential when out in the evening along river banks.
Self sealing thick plastic food bag to keep the insect repellant in – I don’t want that leaking over any of the contents of the bag or even leaking on to the bag itself.
A litre bottle of water in a side pocket
Tripod seat This is something I only occasionally take with me.
Collins Bird Guide

I have occasioanlly squeezed my ASUS netbook in there too with a length of network cable and a pair of USB to CAT5 adapters that allow me to connect my camera to the netbook via USB but with the wire between them being readily available network cable. I have yet to use this in anger but it does work.

Using GIMP to lighten shadows and darken highlights

I tend to use GIMP to edit my photos and one of the things I have found useful is a quick and easy way to lighten shadows and darken highlights.

For those that know some of the terminology and have used GIMP (I don’t pretend to be an expert so bear with me if I describe some of it incorrectly) what I do is use a desaturated, inverted duplicate layer set to “soft light” with reduced opacity.

In more detail:-

When editing your image in GIMP go to the menu option “Layer” then click on “Duplicate Layer”. The duplicate layer will now be active but if you do something else before continuing you will need to click on the duplicate layer in the layers toolbar. We now turn it into a black and white image by going to the menu “Colours” and then click on “Desaturate”. I then usually select “Luminosity” and click on “Ok”. When you have done this a few times you might want to try other options. You can also adjust brightness and contrast but remember that this is supposed to be a quick and easy way of making some improvements to the image. You can get clever with layers and layer masks but if you are into that sort of thing you are beyond this little guide.

Now we can invert the image by going to “Colours” and then “Invert”. We should now have a black and white negative of the original image.

Now “all” we have to do is blend this with the colour original by going to the “Layers” dockable window. Press Ctrl and L if you can’t find it. In this window change the Mode to “Soft Light” and reduce the opacity to give you the image you want. You can turn the duplicate layer on and off to see the effect by clicking the “eye” in the check box next to the duplicate layer in the dockable Layer window.