Wednesday, November 16, 2011
And, don't forget to read your camera's manual, read it again, and take it with you when you shoot. (After all, my "real" job, is as a technical writer.)
For more information, I highly recommend Bryan Peterson’s “Understanding Exposure”.
For example, Landscape typically chooses a mid-range aperture (11 to 20) because everything is usually about the same distance away, and a safe shutter speed (60 to 125) to make sure there is enough light. For ISO, it assumes there’s sufficient available light, so probably doesn’t have to boost the ISO beyond 100 or 200. Night mode on the other hand, assumes there is very little light, so chooses a high ISO and a safe, possibly slowish, shutter speed, and doesn’t really care about the aperture, so chooses something (4.5 and up) that will produce a “good” exposure.
I must confess that I haven’t used these too much, so I’m probably off the mark on how they work. In any event, I suggest that you use them when you need to, but recognize that they are taking a best guess.
If the image is overexposed (i.e., too much light is entering the camera), it will look something like “+ ||| 0 . . - ”, in which case you need to adjust the exposure to use one or more of a slower shutter speed, smaller aperture, or lower ISO to ensure a “good” exposure.
If the image is underexposed, it will look something like “+. . 0 ||| -”, in which case you need adjust the exposure to use one or more of a faster shutter speed, larger aperture, or higher ISO to ensure a “good” exposure.
This is my fav because I’m usually not shooting moving subjects and want to control depth of field. In this mode you choose the aperture (again using one of the command dials) and the camera chooses the shutter speed that will produce a “good” exposure.
Shutter Speed Priority (sometimes shown as just “S”)
In this mode you choose the shutter speed (again using one of the command dials) and the camera chooses the aperture that will produce a “good” exposure.
Once you select Program mode, you use one of the command dials to scroll through the combinations and then select the one that will best capture what you are trying to achieve. For example, if you want to freeze the action, select a combination with a fast shutter speed (i.e., high number, e.g., 500) and the camera will choose the aperture.
Similarly, if you want a shallow depth of field to make the subject stand out from the background, select a combination with a wide aperture (i.e., small number, e.g., 3.5) and let the camera choose a shutter speed that will produce a good exposure.
Note that you may also need to select your ISO setting (assuming your camera enables this for this mode) based on the available light, e.g., 100-200 if you’re outdoors on a sunny day, or 400 and up if it’s cloudy, or even higher in low-light situations.
Program mode is particularly useful when you want to easily capture a number of different types of exposures - some where the shutter speed is most important, and others where you want to control depth of field. I use it when I'm wandering around without knowing exactly what I'm looking for :).
For a brief explanation of these settings, see my Exposure Basics.
Auto is perfect if you need a “grab shot”, or if you are in a situation where you don’t have time to fiddle with your camera settings. On the other hand, it not may achieve the result you are looking for.
Don’t get me wrong – there have been plenty of situations where I thought I could be smarter than the camera’s Auto settings, but was sorely disappointed at the results, especially indoor shots in low light. I have learned to take a shot in Auto first to see what the camera thinks is best, and then use that as a guide when I switch to Aperture Priority or Manual.
With lower ISO settings, you will need one or more of, greater available light, slower shutter speeds, and wider apertures, but you will get less noise. The bottom line – don’t boost the ISO unless you really need to.
Understanding which aperture settings to use can be confusing because of the fact that the higher the number, the smaller the aperture, but the greater portion of the image that will be in focus. Just remember that higher aperture numbers mean more of your image will be in focus. And of course, lower numbers mean that less will be in focus (shallow depth of field), which may be what you want when you are taking a portrait, or a flower that you want to stand out from the background.
F/7.1 - Not that low (wide) but I was close to the grass
To help remember how aperture affects DOF, I like to use the analogy of squinting versus opening your eyes wide. If you squint at something, more of your field of vision is in focus, but it’s all slightly blurry. If you open your eyes wide, what you are looking at directly is in focus, but objects in the periphery aren’t. So too with aperture – smaller apertures (high numbers) mean it’s all in focus, whereas, wider apertures (smaller numbers) mean that only what you are looking at directly is in focus. Well, it works for me…
The higher the number, the less light enters the camera, but the more likely you are to freeze the action in the image you are capturing. If you’re shooting a moving subject, a higher shutter speed is probably appropriate.
The lower the number, the more light enters the camera and the less likely that the entire image will be in focus. Unless you are using a tripod or your camera or lens has built-in vibration reduction, you probably don’t want to use shutter speeds much lower than 60, otherwise you risk a blurry image. However, longer exposures of say ½ a second or longer (again, using a tripod) can produce some very cool effects.
RAW files are exactly what the term implies – the actual bits captured by your camera in its native format. Nothing is lost in the in-camera conversion to JPEG.
Even if you aren’t interested in messing with RAW files right now, you may well be later.
And here's a JPEG produced from the same RAW file edited in Lightroom.
Sure, there is an overhead in terms of capturing and storing RAW files, but if you do any sort of post-processing of your JPEGs already, you might be amazed at how much better your results are when you work with RAW.
For an excellent technical explanation of why I believe you should always include RAW in your image quality settings (probably along with JPEG), check out Thom Hogan’s FAQ page where he addresses the question “Do I really need to shoot NEF? Isn't JPEG good enough?”.
Here's another take on the pros and cons of shooting RAW from Wikipedia:
If you're already converting your JPEGs to TIFs during the editing process, chances are you are converting them back to JPEGs at the end of the process. Starting with RAW and ending with JPEG actually removes one file conversion. And the non-destructive editing with Capture NX2 (and Lightroom), means that you wouldn't need to save the intermediary TIF created from the JPEG.
To be honest, I often convert edited RAW files to TIFs to perform special tasks that I can do only with Photoshop or occasionally with ACDSee Pro. But that's just how I work.
Working with RAW does mean learning new software or at least additional features of your current software. However, once you’re comfortable editing RAW images, I’m pretty sure that you’ll feel that the effort was worth it.
That’s not to say that you will always need to process the RAW files. In cases where you are planning just to post certain images to Facebook or email them, then making leveling and other relatively minor corrections directly to the JPEGs (accepting some loss in quality), makes perfect sense. However, if you are trying to “recover” an image that wasn’t exposed correctly (or the way you wanted), I believe that you are far more likely to be successful if you work with the RAW file.
Here's a JPEG produced from an unedited RAW file.
And here's a JPEG produced from an edited version of the same RAW file with some D-lighting, added saturation and few other minor adjustments.
Workflow is really all about personal preferences, so I'll have to say the jury is out on this one...
I should point out that my current camera is a Nikon D7000 and before that, my first DSLR was a Nikon D80. So, I can really only speak to processing what Nikon calls NEF files when referring to RAW files.
Nikon ViewNX 2
For Nikon users like me, there is the free ViewNX 2, which lets you view, organize, print, and email image files. It also lets you edit images, including RAW images, by adjusting:
- exposure compensation
- picture control
- white balance
Here’s the link to the ViewNX 2 download.
Nikon Capture NX2
A step up from ViewNX 2 is Capture NX2 (I don’t get why these two products use different naming conventions). Capture NX2 offers tons more functionality than ViewNX 2, including:
- batch tools for applying adjustments made on one image to others, renaming and converting files to other formats
- color control points which enable you to modify color, saturation, brightness and other attributes to selected areas of the image
- D-lighting (including a better quality option)
- distortion control
- levels and curves and auto levels
- noise reduction (including a faster and a better quality option)
- unsharp mask and other focus corrections
Okay, it’s not cheap, and admittedly not as feature-packed as Adobe’s Lightroom (LR), which from November 23-29 is on sale for US$199. But in many ways I prefer it over LR which, like many of Adobe’s products, requires you to import your images before you can work with them. I personally find that to be a pain. Of course you can also test drive LR as I did a couple of times. When I looked the other day, the web site doesn’t actually indicate how long the trial period is, but probably 30 days.
Here's a link to the free 60-day Capture NX2 trial.
This past August I picked up a Hitachi 2TB internal drive for about $110 at TigerDirect. In doing some research for this post I discovered that hard drive prices have gone way up since then.
When I looked further, I found an article on TMC Net quoting blogger Marc Bevand whose recent post is titled “1TB Hard Drive Prices up 180% in a Month”. The culprit? - flooding in Thailand, where a large percentage of the hard drives produced in the world are made.
Okay, I have to concede that hard drives, for now at least, are fairly expensive, but I still don't think this is a show stopper long term.
Top 5 Reasons People Don't Shoot RAW - Part 3.
Tuesday, November 8, 2011
- Memory cards with enough capacity to store RAW files are too expensive.
- Hard drives with enough capacity to store RAW files are too expensive.
- Software required to process RAW files is too expensive.
- RAW files would complicate my post-processing workflow.
- JPEG files are probably as good as RAW anyway.
Excuse #1 - Memory cards are too expensive
Before our trip to New York in April of this year, Adorama (which I’ve always wanted to visit) had Sandisk Extreme Pro 16GB SDHC UHS-1 45MB/s cards for sale for $69 USD. At the time, Vistek and Henry’s in Toronto either didn’t have them, or were selling them for a lot more money. I bought two at Adorama for under $150 CAD.
Yesterday I saw that both Henry’s and Vistek are selling what I believe is the same card for $79.99. My 16.2MP D7000 has two card slots, so with two of these cards installed, I can store over 600 images saved in both RAW and JPEG Fine formats!
Of course you can get away with less expensive cards (I wanted the class 10 cards recommended for the HD video on the D7000).
Top 5 Reasons People Don't Shoot RAW – Part 2