Tuesday, July 5, 2016

Basic Photography: Using Photomatix Essential to boost dynamic range in your images

If you want the best possible native dynamic range in your photos then you should buy a full sensor camera. If you don't have the money for the latest full frame then you may want to get a crop sensor camera and pay $39.00 US for Photomatix Essentials. I do my processing with Corel Paintshop Pro X 8, but often, I additionally use Photomatix Essentials. What I have found is that Photomatix Essentials helps me boost my dynamic range quite a bit without having the halos and other things that accompanies other HDR tone-mapping. The image on the left is taken along the Mississippi River late in the afternoon, close to the blue hour. I was able to boost the dynamic range with the fusion function in Photomatix Essentials. It enhances the details, brightens the image, and gives the appearance of HDR that is not over the top. I seldom use the HDR with tone-mapping presets. However, the fusion preset is perfect.

Here are a couple of screen shots that show the workings of Photomatix Essentials.  It works like most other HDR programs. You can select multiple bracketed images to merge into a HDR image. Many of them incorporate tone-mapping with the HDR, but there are a few presets on this program that use fusion. As I understand it fusion simply fuses together the best aspects of the image to make the dynamic range greater. It fuses the lighter of the shaded areas, and the darker of the highlighted areas to bring the dynamic range into something that more replicates what the eyes see. I have used the above image to show how I made the fused copy.

It is a relatively simple program to use. The Photomatix Essential program is pretty basic without a lot of bells and whistles. You can buy a professional program called Photomatix Pro. The essentials program is $39 & the pro program is $99. You can find these at http://www.hdrsoft.com/ I only use it to boost the dynamic range of my photos. I do not shoot bracketed images per se. I make the brackets with PSP X8. Furthermore, I do not even shoot RAW images. Oh I can see the eyebrows raising right now but it is the truth. I do not want to take the time to process RAW images so I shoot in jpeg. I think the results speak for themselves. I am sure that if you were to shoot RAW that you would get even better results than I get.

However, because I shoot jpeg, I have to do my brackets differently. The closer I make the bracketed photos to each other the less problem I have with noise. I don't make them anywhere near a stop apart. I make them closer to 1/3 stop difference and sometimes even less than that. I get the best results this way because it keeps the noise down. I like sharp photos and reducing noise tends to soften images. Photomatix has a function for lowering noise in the process. I use that function as it is not extreme. The only place I do not use this is with my portraits. I think that HDR of any kind makes the facial features too hard.

Sunday, July 3, 2016

Basic Photography: Low light Photography

Many photographers still prefer film to digital photography. There is a considerable amount of nostalgia for film produced images. There is one area however where digital photography is well ahead of film, and as the months and years go on the gap is widening. The area where digital cameras are well ahead of film counterparts is in low light photography. There is a correlation between ASA (film speed) and ISO (digital image speed.) Whereas 800 ASA was extremely fast film, digital cameras of two iterations back had an ISO of 1600 to 3200 and now, most cameras go up to at least 12,800 ISO. While none of them perform that well at the highest ISO setting, most all current cameras function well at 3200 ISO, by that I mean, produce images with very little noise, and a lot of them do well at 6400 ISO. Sony has a full frame A7SII, that has a native ISO of over 104,000 ISO. What does all of this mean for low light photography? Well, if you have a fast prime lens, f/2.8 or faster, and a camera that performs well at 3200 ISO you can get very good hand-held low light shots. That was not possible even two or three years ago. The above image was with an f/2.8 lens at 3200 ISO. The lens is pretty sharp wide open so you get good results without a tripod.

There are essentially two ways to get good results in low light photography. One is with a fast prime
lens and a camera that functions well at a higher ISO like described above, and the other is the more traditional way, using a tripod, and using a very slow shutter speed. An example would be setting the camera at f/12, ISO 200, and a shutter speed of 5 seconds. That method will get the sharpest low light images. The image on the right was shot in that manner. If you click on the image to enlarge it you will see that the lights are starred. That is a characteristic of low light images shot manually with a narrower f/stop and a slow shutter speed. With that type of photography you have to use a tripod to keep it from blurring. Since I have an APS-C sensor I like to do a form of HDR fusion to get a greater dynamic range for my low light images. Those shooting full frame sensors have a natural dynamic range that is greater and can easily get by with one image. The secret I have discovered for doing HDR fusion with low light images is to make bracket images very close to each other, that is, less than 1/3 EV apart. The closer they are to each other in exposure brightness the less noise. I do not shoot three EV brackets. I create them with my Corel PSP X8 from one shot.

This image on the left was shot hand-held at dusk just before the sun disappeared in what is known as the blue hour. I used the same technique to create close together bracketed photos to make sure that the noise is negligible. The slightly higher dynamic range makes the photo pop and makes it easier to make it sharp. Even when it is a hand-held image shot at f/5.6 to f/7.1. When the closest object is further than 30 ft away then you get a pretty sharp image all the way to infinity. Low light images, at sunset or darker, evening city scapes and street scenes are much more interesting than images shot at high noon or mid day. The best times for interesting photos is early in the morning or late in the afternoon and evening.

One thing that you must do is experiment. You have to be willing to shoot some failures to find out how to be successful. The once nice thing about digital cameras is that you can see the results in the LCD view screen. This makes it possible to perfect what you are doing without returning to the dark room to find out what you accomplished. The other thing that I recommend is to check your exposure meter to be sure that you are at the correct exposure. When I shoot in regular daylight, I like to set my camera at -.70 EV, but not with low light shots. There I want to make sure that I am at .0+/- or if anything at +.30 EV or above. This makes the results much more appealing and avoids having images that are too dark to salvage. If you have a camera that will shoot fairly good images at 1600 ISO, and you have a fast prime, either f/2 or f/2.8, you will find that you can get some really good results hand-held... however, no matter what digital camera you have, you can use manual, a tripod and a slow shutter speed and get really good results.