Need Multiple Batteries Charged?

This article is one for those who do a fair amount of travel and for those of us who have multiple cameras. You run into a little bit of a problem with the batteries. Steven has covered in the past the Camera Battery Hack. We have also linked to other Camera battery hacks to extend those star trails long after the stock battery would have died.

What I want to talk about here is chargers for your stock batteries and here is the rub most of the chargers you buy for camera battery are specific for only one battery. Recharging batteries is a pain because batteries drain and recharge at different rates so at sometime you are left with 3 dead batteries all different types. That takes three different chargers all of which charge at different rates. And carrying more chargers means more chargers to forget, more outlets that are occupied.  And since each charger charges at a different you have to keep checking and checking the chargers to swap in the discharged batteries.

Suppose you move between hotels and locations in the remote Alps with your photo buddies on a once-in-a-lifetime time trip. But, you just forgot your charger in civilization. Well sucks for you. You will have to nurse that battery and it looks like no star circles for you. Well your friend might have you covered. If he had the Digipower travel charger which can charge multiple batteries at the same time. So lets look at the specs of the charger…North America/Japan and European Voltages (100-240VAC 50-60Hz 0.2A) (even the ability to charge two batteries at once.) These changers also come with the wall outlet adapters no need for use or buy another voltage converter. There is also a safety timer to prevent batteries from over charging as well as short circuit protection. The best part is the multiple inserts for different battery types. No matter where you are or what type of battery your buddies have, you got it covered in one charger. These multi-chargers are typically sold as brand specific Nikon, Canon, or Sony but they cover a large number of battery types in that brand. All of the interchangeable plates are included so no need ordering separate plates or voltage converters.  In the version I got (Nikon) it cover 5 battery types EN-EL3e (D90,D300, D300S, D700) EN-EL9/9a D40x D60, D3000, EN-E14 P7000 D3100, D5100, D7700, EN-EL15 D7000, V1 D800, D600, EN-EL20 J1. This covers all of Nikon’s pro cameras so your main body and the backup are covered.  Sweet now back to shooting.

Another system with interchangeable charger plates is the Delkin single or dual plate charging system.

Of course the downside to all of these systems is that they require you not only to carry the charger, but also the plates for the batteries you may need.

Lenmar Plate Charging System (with USB power outlet)

 

Bracketing 101

Memory is cheap. Some shots are rare – especially moon alignments and other ephemeral   events. The worst thing that can happen besides a horrible accident or equipment disaster is to leave the scene of a shot-of-a-lifetime and discover every shot is seriously over or under exposed. Of course out of focus is right up there in the kick yourself list.

Film photographers have been “bracketing” shots since the medium started because unlike digital, film people can’t be sure of what they captured until they process the film.  Some events transpire quickly enough that even digital photographers can not (or should not) take the time to “check” their exposures.  Solution:  bracket.

And what about those tricky lighting situations where the foreground is bright and the background is dark – or vice versa. Solution: bracket.

And then there are those situations were a slightly longer exposure – or a slightly shorter exposure will get a more pleasing result. Solution: bracket.

There are two primary ways to bracket shots – set up Auto Exposure Bracketing (AEB) in your camera, or do it manually.  There is a third way too: do BOTH. And there is a fourth way described below. In every case I describe I use a tripod. If you’re not using a tripod for this kind of shooting you might as well smear vaseline on your lens since you’re making your life needlessly harder.

What is a bracket?

Bracket means to vary some element of the exposure to capture the possible range of light of interest to the photographer. Usually the best thing to bracket around is the exposure length because varying the aperture may change the depth of field (though that could be interesting), varying the ISO may change the noise characteristics of the result – also potentially interesting.

To catch the best exposure with minimal fumbling I set my camera in Auto Exposure Bracketing mode. As a Canon shooter I generally have it set to -2, 0 and +2 exposures . There is so much latitude in RAW data that it doesn’t make sense to me to shoot in fractional stop or one stop increments. -2 and +2 mean two-stop less and two-stops more exposure than the starting settings.  In real numbers if my starting exposure is 1/100 of a second, the -2 exposure will be 1/400 of a second (1/2 of 1/2 of 1/100) and the +2 exposure will be 1/25 of a second (2  x 2 x 1/100).  For some scenes -2 to +2 is NOT ENOUGH. In fact, it’s often not enough when you have a bright object like the moon and darker objects like fading light on a landscape.

When Time is Critically Important – Frantic Mode Bracketing

When the moon is setting or rising, I may have mere seconds to get the exact alignment I want.  Before the exact moment arrives I have already taken several exposures to be sure I am in the right “ball park”. I look at the histogram, check to see if anything has blown out and select a starting exposure that seems about right.  Sometimes I get that starting exposure by just letting the camera pick it.  I then switch to Manual mode and dial in the exposure that the camera determined for me.

On my Canon cameras in Manual mode the top wheel adjusts the exposure time.  My frantic shooting sequence will then go like this:  set the best guess exposure with +/- 2 bracketing.  Shoot.  Spin the wheel about nine clicks to the left. Shoot. Spin the wheel about twenty-one clicks to the right. Shoot.  When I say shoot, I mean the WHOLE bracket, not just one shot. Two ways to shoot the whole bracket are to:

  1. Set the camera into continuous exposure mode and hold down the shutter button (or better yet, shutter release button), or
  2. Use the 2-second delay mode which will automatically fire off all three shots in the bracket.

I go nine clicks to the left because I have my camera set to increment in 1/3 stops. Nine clicks is therefore 3 stops less exposure.  Is it important that it be EXACTLY 9 clicks – no, not very.  By shooting in this way when done I will have shots at -2,0,+2, -5,-3,-1, +3,+5,+7  Arranged in order the shots span: -5,-3,-1,0,1,3,5,7.

It also happens that “nine clicks” is about two “flicks” to the left for me. While twenty one clicks to the right is four “flicks” and a few more clicks for good measure.

Why Don’t I Just Set My AEB to -5 to +7?

There is no camera that I know of that can do this. Notice how I have -1,0,+1 in the mix, but all the other elements are increments of 2?  Yeah, that doesn’t exist in any camera (yet), but some Canon models can go 2,3,5 or 7 shots in the range with up to 3-stops difference.  Some Nikon models can go to 8 exposures at up to 2 stops (or EV as Nikon calls them).  And there is another reason, too. While I have to manually intervene in the process, I can prioritize the shooting order.  I tend to favor shooting the longer shots toward the end, but I can reverse that if I think the longer shots are the more important ones.

Method Four – Tell the Camera Where to Meter

What I described earlier is what I’d refer to as “frantic” mode.  When every second counts because the scene is changing. If my scene is a bit more static, for example when I’m shooting for an High Dynamic Range (HDR) I use another trick.  I make the camera do the work to get the right shots.  Imagine this scene:  a bright sunset or sunrise, with dark but important foreground elements.  Here I need the sky to be on, the landscape to be “on” and some reasonable transition from one to the other to make any HDR processing work well.

On my Canon I set my camera to AV (aperture priority), I use the Live View feature with zoom.  By turning off auto-focus a rectangle appears on the Live View. I can move this rectangle around and zoom in 5x or 10x.  To get the sky exposure right I’ll move the rectangle to the brightest part of the sky, zoom in so it’s all or almost all bright sky and fire. The camera meters on the rectangle in this case – so my bright sky exposure will be right. If there is a lot of gradation in the sky color, I may find a “moderately” bright sky and repeat.  I then find a mid-tones area in the shot, move the rectangle there, zoom in and fire again.  Lastly I find a shadow area – move the rectangle, zoom in and fire.  In each case I’ve allowed the camera to select the exposures – oh, and I usually have AEB on, too.

 

Theory vs Reality in Photography

Several topics in this BLOG have provoked impassioned debate. We really appreciate that. Steven is a Software Engineer by training. Eric is a Molecular Biologist, and Harold is a jack of all trades. In addition to being an author and professional photographer, Harold’s background includes being an Attorney at Law and a Software Engineer. We do “geek” like nobody’s business!

I, Steven am raising the geek card just to let you know that we do care about precision – but we care MORE about great photography and applying real-world principles to real-world problems.

Streaking Or Not?

The biggest debate has been about what factors lead to streaking (trailing) in Night Photography shots of the stars. Shots of the night sky may produce noticeable streaks if the exposure length exceeds certain bounds with specific camera factors (focal length, sensor size and sensor geometry). But there are a huge set of assumptions behind the visibility of those streaks that are often overlooked. One assumption is that the finished image sizes are proportional to the size of the sensor used to create them – when does that happen in real life? Another assumption is that the viewing distance is proportionally related to the finished image size. These sound like they are reasonable, but in the real world, a print from a crop camera and a full-frame camera are extremely likely to  be made in the same finished sized and viewed from whatever distance the viewer chooses!

In the desire to get the math exactly right, many people trip over one or more of those assumptions. Our article about why the 600 Rule is a misguided way to determine the proper exposure length has had many proponents and opponents espousing the “inerrancy of the mathematics” and all the missing factors we may not have included. I love math, but: my assertion is that Reality beats theory when producing an image.  And that’s why the conclusion of the article is that the proper exposure length is an aesthetic decision more than a mathematical one.  The mathematics guide, but do not govern what the best choice(s) may be.

All Photography Involves Tradeoffs

I really enjoyed my Physics classes, especially mechanics. But I also remember all those exercises that included clauses like “neglecting friction”… In the real world friction with the the air and from tire contact on the ground is why a car on a flat road comes to a stop even though no brakes are applied.  Air friction (drag) is why it takes eight times as much power for a plane to fly twice as fast.

The reality of physic is why a lens, or sensor is always a tradeoff of something for something else. Perfect optics or a perfect sensor behavior is not possible at any cost. In the same way, a photographic exposure is always a tradeoff of one thing for another. If you need a faster exposure with a given amount of light you can: increase the exposure time, increase the sensitivity, or admit more light by opening the aperture. Of course you can also change more than one thing at a time. Indeed you MUST change more than one thing. Any change to one of the three factors requires a corresponding change to one or more of the other factors.

What Exposure Settings Should I Use?

If you ask me this question, I apologize in advance for rolling my eyes (it has been known to happen). I can give you a STARTING point, but remember that a starting point involves tradeoffs and conditions that can not be entirely foreseen. How warm is it? How much moisture, dust or particulates are in the air? How much turbulence in the atmosphere? How much artificial (or natural light)? What are the predominate colors of the light (white balance)? How efficient is your sensor? How sharp are your optics? How far away is your foreground from your background? What is that largest aperture available? How sharp is your lens at that aperture and at that zoom? What is important to you in the scene you’re trying to capture? And what are you trying to accomplish?

My best advice: try an exposure and see what you get. When all there was was film, precision was a lot more important than it is now in the digital world where you can immediately see the result with a histogram and a myriad of other data to help you decide what to try next.

In fact, here is your assignment.  Go out when it is dark and shoot a photo of the moon.  How dark is entirely up to you. Your photo MUST show the same kind of detail that you can see with your eye – the craters and the gradations from light to dark areas.  Use a telephoto lens – notice I am not telling you how telephoto, that’s also your choice. If the moon is “blown out” – and it probably will be, decrease the exposure. Keep taking photos until you get as much detail as you can.  You will almost certainly need to use manual mode to set your exposures.

What settings did you come up with?  In our “Catching the Moon” webinars we provide starting settings and also advice about how those settings may need to be changed.

For an extra challenge… see if you can get the moon AND stars in the same shot. What settings did that require?**

4 Moons 4 U [B_049969] Composite

**In retrospect, it was evil of me to suggest this. In only the most extraordinary circumstances is it possible with current technology to get a featured moon AND stars.  The example above required 3 separate exposures.

 

Hunting Comets and other faint objects in not-dark skies

AirGlow Comet [5_070386]

It turns out the much hyped PanSTARRS C/2011L4 Comet is not living up to the hype. Unfortunately failure to meet the over exhuberant expectations  is common since predicting brightness and visibility of an object like a comet is a difficult science. In fact, it’s part science, part black art and part good guessing – mostly the latter.

The photo above was taken on March 12 when the moon and PanSTARRS nestled closely together. The close quarters made finding the comet much easier despite the bands of clouds passing by.  The strategy for finding the comet in that case was simple: use a telephoto lens, put the moon at the right edge of the photo and take different exposures periodically and at different settings (e.g. +2, 0, and -2 stops). Then hunt for smudges.

The IDEAL telephoto lens would be one that was a few angular degrees wider than the difference between the moon’s position and the comet’s position. How to determine the position of each is discussed in the last section below. Figuring out the angular view of your lens is easy using online tools like this one from Tawbaware, makers of Image Stacker (like that program!). If you know the field of view at your minimum and maximum zoom, you can use that information to your advantage.

Finding the Comet with a Nearby Moon

The point at the moon strategy made finding the comet easy because:

  1. There is no way you’d be able to see the comet if you were not able to find the much brighter moon nearby.
  2. On that one night, the comet and the moon were within 4 degrees of one another.  That’s quite close.

I know some people tried to find the comet using wide angle lenses. That strategy might work, but the comet is such a tiny thing and it’s visibility is so tenuous based on the atmosphere, light pollution, and sky brightness that you may only realize – as many did – that you captured the comet after carefully inspecting your photos at home.

Contrails and Comet Tails [B_050938]

The truth is you are unlikely to see PanSTARRS by eye or in your camera’s view finder unless your conditions are nearly ideal.  Hopefully ISON which is coming in December will be brighter and better.

Finding the Comet when the Moon is Farther Away

The following night, both the comet and the moon had moved relative to the sky. On March 13, the moon was 12.5 degrees above the comet and about 4 degrees farther west (again, how I knew this is coming in just a minute).  So one simple strategy for finding the comet would be to zoom your telephoto lens so that it has a field of view of about 14 to 15 degrees in the long direction which for me, is 80 millimeters focal length on a 1.6 crop factor camera.

On a tripod with the camera in portrait orientation adjust the view so that the the moon is in the upper left of the frame. Shoot bracketed shots. Check the lower right corner of each one for the tell-tale comet smudge.  Keep readjusting the view so the moon remains in the upper left for each shot. Zoom out a little bit too, in case your geometry is a little off. Eventually as it gets dark enough or the sky clear enough you should find it.

In fact the way I found the comet last night without using my camera but by using my telescope. The program Clinometer (on my iPhone) measures angles. I sighted the moon with my 8″ Dobsonian telescope and measured the angle along the telescope barrel using the inclinometer program. I then lowered the altitude (elevation angle) of the telescope by 12 degrees to match the altitude of the comet. Then I slowly rotated the telescope northward until I found the comet.  It wasn’t easy from my urban location, but it wasn’t impossible either.  By the time I was able to find the comet it was only about 6 degrees high in the sky – that’s way too low if you have trees, hills, and houses nearby to deal with.  In theory, this strategy would work with a telephoto lens or with binoculars, however, binoculars need to be steady and where I spied from last night had streetlights in the distance and the flare and glare from those streetlights made finding the faint comet nigh impossible.

What if there is no Moon to Find the Comet With?

Unfortunately starting on March 14th, the moon will be quite far from the comet, so the opposite strategy is required:  Use a landmark in a known direction as the starting point and look “upward” from the horizon.  In other words, zoom your telephoto lens so that the field of view covers the angle from the horizon to the comets altitude (angle) above the horizon.  Don’t forget that as the earth spins this angle changes every minute! Orient you camera in landscape mode and point it as close as you can to the correct direction (azimuth). Look along the top of the frame to see if you’ve captured the comet.

IMG_1622.PNG

SpyGlass’s view shows the direction the camera is facing (Azimuth) and the elevation angle (Altitude)

But what direction should you point your lens or telescope? Use a compass application or actual compass. BEWARE however as the compass applications have lots of gotchas and are only accurate to about 5-10 degrees.  And if you aren’t sure how to use a real compass your local magnetic declination might bite you. Better would be a GPS with a built-in calibrate-able compass.  And perhaps even better still would be to use an application like TPE (which I discuss in my Catching the Moon Webinars) to calculate the correct azimuth from the location you plan to stand.  An application that might help a lot is “SpyGlass
however don’t forget that I found the directional accuracy of my iPhone and iPad to be pretty poor.  Being off by 5 degrees may mean looking in the wrong place.

How Do I Know the Altitude and Azimuth for the Comet?

Stellarium_MoonMarch14

Unfortunately, that’s a tough one.  I use the free program Stellarium. I then added the comet to the “Solar System Data Base” (search around on the web and you’ll find instructions). I selected my viewing location, dialed in the time, did a search for good ‘ol C/2011 L4 and let it tell me the azimuth and altitude.

PanStarrs_March14

Above I’ve dialed up the time and clicked the moon. The highlighted line shows me the azimuth (direction) and altitude (angle above the horizon) for the moon which at that time are 264 degrees or just a little south of west, and 30.5 degrees high.  Clicking on the comet shows 272 degrees – a tiny bit north of west and 9.5 degrees.  So now we know that the comet will be 8 degrees north and 21 degrees south of the moon – and that won’t change significantly for the rest of the night.

Since we also know the direction for the comet is about due west at this time, we can apply the telephoto-lens horizon trick I described earlier.

Another way you can find the azimuth and altitude is by checking my animation HERE – note that the animation is correct for San Francisco  (and most places nearby).  There is also a table of the azimuth and elevation in the text of the Flickr post.

 

By the way, one way to find the right spot on the horizon is to use the sunset location as a guide.

CometIllustration

Now Open: The Store

So many of our students at our webinars and workshops as well as our website visitors ask us about our Notes, Instructional Videos and Photoshop additions that it was time to make it possible to deliver them.  So we created a digital store integrated with this blog.  In fact, we’ve only had the store open for two weeks and already we have a clear bestseller:

Advanced Stacking Action Bundle
Includes the easy to install Advanced Photoshop action, a 2 hour video on creating star trails, notes (PDF) on creating star trails and practice files. Compatible with Photoshop CS4, CS5 and CS6. NOT Compatible with Photoshop Elements, Lightroom or earlier versions of Photoshop.

Making It So

But making it so was not a straight line path from where we were to where we wanted to go. We toyed with a variety of things to create a store. Using PayPal buttons directly – simple and maddeningly painful at the same time, using ZenCart, and looking at a few others solutions.

Ultimately we wanted something relatively simple. Something that could handle a small, but growing array of products – all digital, and that would be relatively easy to integrate into the BLOG without breaking off limbs or snapping frazzled nerves. We settled on WP E-Store. It’s neither flawless nor as spectacularly simple to get working as we would want it to be, but it is well featured and well supported.

I should probably make a note that I, Steven, am capable of twiddling with HTML, circumspect of all CSS (because I’ve never found it to be pleasant to deal with), able to write JavaScript and PHP when needed – but prefer not to. If none of that makes sense to you, that might be fine unless you decide to embark on creating a store because I’ve already learned that I have needed all those skills in some form already.

We want a store secure against theft, hacks and intrusion, that is easy to use and easy to configure. We also want to offer discounts to people who attend our Webinars and Workshops as well as repeat customers. Using PayPal directly proved unmanageable. Our store also needs to manage the digital content that gets created on an almost daily basis. We had no expectation or illusion that we would sell prints or images through this store. In fact, Steven has a well featured means for selling hard goods through ZenFolio. Interestingly most Steven’s print sales occur in the United Kingdom – likely because they see Steven’s images in the Royal Observatory. ZenFolio is great for selling prints and mounted images – even iPhone cases!

WP eStore

What we like about WP eStore is that it does handle the key things we want: digital sales through PayPal (and credit cards), and secure encrypted links for digital goods and a nice simple interface for our clients and customers.

What WP eStore lacks, however are a number of things including a simple way to process refunds (always a painful thing through PayPal), more configurability of the display of products and the shopping cart and a few gotchas in the way you configure products. For example, with WP eStore you can specify a “thumbnail” image for a product – but by default the thumbnail will be clickable and go to the thumbnail image. That’s completely silly.

Of course since we purchased WP eStore we’ve also noticed a lot of other competitors, including WooCommerce which looks snazzy, but it appears you get nickeled and dimed to death to get all the pieces together.

Biggest Obstacle

The biggest impediment to our eStore is our theme.  Theme? Yes, the page layouts are controlled by a WordPress theme. Unfortunately the theme we like is not as customizable as we’d like. That spiffy graphic at the top, for example clutters up the store so we are planning to either switch themes or hack up the Twenty-Ten theme we are using.

What is Ahead?

One day we hope to also offer free and paid Webinar registration through the store. And perhaps even workshops, too. Meanwhile the place to find webinars and workshops is either at:

Still reading. Perhaps you just arrived at the best part… a discount coupon good for 20% off of everything in the store:    WELCOME

Oh, and if you would like to see if a Webinar will work for you and your set up, you can join a FREE webinar to kick the tires on March 12, 2013. We hope to see you there!