Category Archives: High Dynamic Range (HDR)

Review: CamRanger

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I am always looking for the best solutions for automating my night photography. In fact, I recently reviewed a litany of products. At the time I didn’t know about the CamRanger product – my friend Rob C. told me about it.

I am now the owner of a CamRanger. Here are my first impressions:

IMG_1552

iPhone Application

  1. I ordered from the CamRanger website, selected two day delivery. The box came all the way across the US. From Virginia to California and it arrived in two days. Woohoo! Great store and interaction.  It’s also available through Amazon, but doesn’t qualify for Prime. I figure if I’m going to pay for shipping I’ll order it directly from the company and hope they keep a bit more of the cash.  By the way I paid with PayPal. Sweet. 
  2. The packaging is reminiscent of the iPhone. Everything is nicely tucked into a little box. I was worried briefly because I also ordered two extra batteries. Thankfully they were tucked into the same box.
  3. Included were: Quick start instructions, a charger (wall wart), charger cable, USB to mini USB to connect to the camera, Ethernet cable (for upgrading the firmware), the batteries, a cigarette sized-packet with the CamRanger unit, and a carry pouch with a velcro closure and a carbiner clip.

The CamRanger is an incarnation of the TP-Link portable wireless router. It even says so on the batteries and under the case. Really clever approach! Kudos to them. Of course the firmware has been customized, and they are using the USB connector to drive the camera.  With that arrangement they can do a WHOLE lot more than you can do with a lowly intervalometer.

Essential is the CamRanger application for iPad and iPhone. They are planning to roll out other applications, including one for the PC. Since the device is a portable router, theoretically they could even provide some simple browser driven connectivity.  I loaded the app long before I received the box. You can’t get to square one without the device, however – it won’t show you any of its glorious features until it can talk to a camera. Makes some sense since what you can do depends on the camera it connects to.  I found some blemishes with the application which I’ll enumerate in just a moment.

What Can the CamRanger Do?

Before I criticize, let me first explain what you CAN do with this clever device. And this is just scratching the surface.

  • Focus stacking – let CamRanger control incremental focus for maximum depth of field with your macro (or other) shots.
  • Remotely adjust focus (camera auto-focus must be turned on for this).
  • True HDR using exposure time, ISO or f/stop increments. Up to 7 exposures are allowed.  Intervalometers with this feature can only work in low light since they can only crudely control the camera shutter.
  • Monitor “live view” and captured images. Even delete them when they suck. I am slathering at how this will improve my Astrophotography. Have you ever tried to adjust focus of a telescope pointed nearly straight up – it’s a neck breaker.
    IMG_1556

    Delete Images from Camera

  • Intervalometer functions: timelapse, and bulb exposures.
  • Complete control of settings (how complete depends on your camera). Nearly all of the settings can be changed remotely including ISO, f/stop, exposure time, metering mode, image size and type… and more.  I even moved the connection from my Canon 5D Mark II to my cohort’s Nikon D800 and had immediate control of his camera and its unique settings.
  • Some features do require manually changing the camera mode knob. For example to get bulb exposures you must be in Manual mode on a Canon 50D or in Bulb Mode on the 5D Mark II.  These peculiarities vary by camera.
  • CamRanger can do everything the EyeFi can do for sending images. EyeFi isn’t supported on CompactFlash media cameras so CamRanger is a great replacement!
  • IMG_0137Focus by touching the iPad screen.
  • Provides a Live View Histogram.
Touch the iPad to select focus point!
IMG_0128

Landscape Mode

 

 

 

 

IMG_0127

Portrait Mode

IMG_0136

View images from the camera memory card

What Could Use Some Improvement

I’ve ordered my complaints according to how much they affect the way I do most of my work which is night and astrophotography.  Some of these are nitpicking, I know.

  1. There is no sub-second interval for long exposures. I’d love for them to add a “star trail mode” and select the shortest possible interval between shots based on the camera type and behavior. The company says this is a limitation in what they are able to do through the USB connection to the camera.
  2. There appears to be no way to know if a timelapse is running nor can you stop a timelapse in progress.  The CamRanger can continue to run a timelapse sequence without an app driving it.  That’s a plus. But not being able to tell if it is running or to abort a sequence in progress is annoying. CamRanger tells me they are planning to address this in an upcoming release. Yeah!
  3. The pouch for the CamRanger could be improved to:
    • Hold all the items that come in the kit. The pouch can only hold the CamRanger device, USB cable and perhaps an extra battery – not the additional cables or plug-in charger.
    • Add velcro straps so I can wrap them around my tripod leg and secure the pouch to my tripod,
    • Provide a closeable window so I can see at a glance the unit status (i.e.those LEDs which are too bright, see below).
  4. The timelapse settings use spin dials to select the number of exposures and exposure times. The keypad would be more efficient.  It would also be great if the App automatically calculated your elapsed running time based on the number of exposures and a configurable frame rate (like TriggerTrap does). CamRanger is adding the calculation.
  5. The LEDs on the device are pretty doggone bright for night work. Would be great if they were dimmable. Of course that can be achieved by putting the device in the pouch or by putting some semi-opaque tape over the LEDs.
  6. IMG_1564To interact with the CamRanger, you have to switch your iDevice to the WiFi network generated by the CamRanger. Unfortunately that means you can not use your iDevice browser to surf the internet. If there were some fast-switch way to do it, I’d like that. Or better yet, I’d like to integrate the CamRanger into an existing network.
  7. The CamRanger itself comes with a serial number sticker. I’m SURE it will come off or get lost, but you need that serial number to connect to the device. The same serial number can be found on a sticker under the battery cover, though.
  8. The Access Key to join the CamRanger network is all in upper case.  All lower would be easier to type.
  9. My buddy Rob noted that he felt like he was going go have to break the battery cover off. Mine seems to come off quite easily if you hold it correctly.
  10. The CamRanger battery is a custom lithium-ion form factor. You can charge the battery in-device, but there is no additional charger provided.
  11. Sometimes when switching functions, for example when switching to Timer it told me “must turn off live view” which seems a bit strange since it knows how to do it!
  12. I ended up with both my iPad and my iPhone attempting to connect to CamRanger. It caused a problem that was not obviously solvable (Communication Error) until I realized both of my devices were trying to get CamRanger’s attention.

As I noted, some features depend on the way your camera interacts with the USB connection. I didn’t figure out, for example, how to cause my camera to meter the scene for me so that I could manually adjust my exposure – i.e. what I’d normally do with a half-press of my shutter button.

I haven’t tested the range or battery life as yet. Claimed battery life of the CamRanger is 6 hours. There is, however, no on screen indication of the CamRanger’s current battery condition.

Now That I’ve Used it More…

The problems with not being able to see if or stop a timelapse are more than irritating.  The only way to stop a timelapse in progress is to turn off the CamRanger device and turn it back on. It takes about a minute to come back up and meanwhile since the WiFi from CamRanger goes away, my iPad or iPhone will by default switch back to another known network (my home in this case).  That means I have to remember to also switch WiFi networks or I get “unable to communicate”.  I also noticed that for bizarre reasons which are not quite clear I could start a timelapse, but the camera did nothing.  However I *could* use the Capture button.

But that’s not the end of the pain, unfortunately.

  • The Bulb and timelapse settings are not saved. All settings reset to 0 when a timelapse completes.  If you want to re-run the same program – as I do when I take darkframes after my astrophotography sequences – you have to reprogram everything. That’s tedious.
  • Apparently the interface is not smart enough to know how to do HDRs that exceed the camera settings 30″ exposure time.  On my 50D, for example, an HDR sequence that should shoot at 15, 30 and 60 seconds will not be accepted. However that sequence can easily be achieved by using bulb mode for the last shot and that does not require changing the dial on the camera – so the app could figure it out.  I even tried doing this in “Bulb” mode, but it still didn’t seem to work.
  • The biggest pain in the butt is that the “Autofocus” behavior is not preserved.  What this means is I leave the AF button on on the lens, carefully fine tune the focus, turn it to MF (manual focus mode) on CamRanger and take my shots. If, however I am forced to cycle the CamRanger power it reverts to AF mode by default so the first shot will try to autofocus in the dark – which prevents the camera from shooting.  I’d like to set the default behavior to NOT AF even though I have set AF on the lens.
  • It also appears the timelapse is not aware of the drive mode for the camera.  I often set my camera to the 2-second (or 10 second) delay for two reasons: 1. it lights the self timer on the camera so I know when a frame is about to fire, and 2. In delay mode, an Autoexposure bracket (AEB) will automatically complete from a single press of the shutter. The timelapse settings could know that the minimum delay will be the length of the camera self timer delay (plus perhaps a second).  But it doesn’t use that information.

The good news is that the biggest pain points can be fixed in the app. I suspect some of the more advanced things would require the app to know more about the camera – and are thus less likely to be supported.

The other good news is, it really does save me from breaking my neck trying to get my eye down to the view finder or to view the LCD – when objects are high overhead I’ve had to lay down on the ground to see the LCD – blecch. And it’s great fun to watch the images roll in as the timelapse runs – even from indoors while my poor equipment is out shivering in the cold.

Graduated Neutral Density Filters

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In a Flickr discussion, a poster asked whether he should get a hard stop graduated neutral density (GND) filter or a soft one.  But wait, perhaps you would first like to know what a GND is so that I can explain to you why you probably DON’T need one.  Here is a concise article, I’ll wait for you to come back.

In a nutshell, let’s dissect the words: Density means darkening – the denser the darker. Graduated means the amount of darkening changes from top to bottom. Neutral means that while darkening, the color is unchanged.  A neutral density filter is one that darkens the scene to allow a longer exposure – e.g. of a waterfall or ocean to get the “silky water” effect. A good neutral density filter will not distort the color in the scene. The Cokin GND I’ve used, for example adds a purple cast (hue) to the captured image.  Usually photographers employ a GND to darken the sky in a daytime scene so that the sky brightness is not so significantly different from the landscape. By darkening the sky a single exposure can capture sky details (e.g. bright clouds) as well as details in the landscape.

All that’s left now to describe is the difference between a HARD and a SOFT GND. If you read the linked article you already know, but if you didn’t, here is an easy way to disentangle the words: hard is ABRUPT while soft means GRADUAL.  That is, a hard filter has an sharp transition between the dense area and the clear area while a soft filter has a smoother transition.

Can you use a GND at night? Yes!  But normally you will end up using it in the opposite way of the normal use:  e.g. to darken city lights at the ground but leave the night sky undarkened.

Here is an example where you might think of using a GND

Mary Avenue Circular Motion

The lights on the bridge deck and towers are very bright compared to the night sky.  A GND in theory could be used to mask the lower portion of the bridge to control the brightness. And while it will work, it will not work well because somewhere there will be a transition between the darkened part at the bottom and the sky above. If there were no tower, the GND could be used to knock down the lights on the fences and deck with a relatively minor sacrifice.

This scenario repeats itself in daylight situations too. Imagine a lovely tree in your daylit scene instead of a tower and it quickly becomes clear that nature affords very few situations where there is a linear and sharp distinction between the dark area and the light area… the ocean being one clear possibility or perhaps a landscape in a flat-as-flat-can-be field in Kansas.

Here is a better candidate for use of a GND – but still far from ideal:

Incoming [5_034817-5138brPS] Star Trail

A GND could knock down the excessive city lights. But it would also darken the mountain.

While it is certainly desirable to knock down the excessive city lights there is no orientation for a GND that won’t also knock down the brightness of the mountain or a portion of the sky. A triangular GND – if it existed could control the overbright part but since every scene is different the chances of getting a well matching GND are slim.

90% of the time using bracketed exposures and High Dynamic Range processing techniques makes more sense than using a GND. Also by not using a GND there is no additional opportunity for glare, flare, reflections or color cast – and nothing additional to carry lose or break or spend money on!

But before I completely pull the plug on GNDs, here are a few extra tidbits you can employ to get the most out of a GND that you may have:

  1. You can turn a hard GND into a soft one, by moving it up and down while shooting. For this to work, you need a longish exposure and you must be careful not to shake your camera. You also won’t be using the filter holder.
  2. A lower tech approach that works is black carding. Instead of using a neutral density filter you use a flat black card. You hold it for a time (keeping it moving a bit) over the light part of the scene and then remove it. This is exactly analogous to the “dodging” and “burning” process used long ago by Ansel Adams when he wanted to tone down (or up) an area of a photographic print.

The effects of the GND can be duplicated on the computer – and better yet, without the tell tale darkening of things like trees and mountain tops that cross the transition area of the GND filter. Tools like Photomattix and Adobe’s Photoshop Merge-to-HDR can automate the merging of exposures, but to my eye the result is usually somewhere between bizarre and odd looking.  A more effective process is to hand merge your HDR as described by Harold Davis in his book The Photoshop Darkroom 2 or his latest book dedicated to HDR processing – which begins shipping July, 2012.

In Summary

GNDs work, but seldom does one find a bright area separated from a darker area by a straight line – whether gradual or otherwise. Trees, hills, mountains and man made things like to poke up into the sky and look “weird” when darkened via a GND.

The advantages to bracketed HDR photos are many, the drawbacks are few – and it’s one less filter, filter holder, and pouch to take along and one less source of additional reflections, flare, vignetting, or color problems.

In fact, I’m not really sure where my GND is anymore, or the holder for it which was a beast to manage.

More Resources

Postscript

I did NOT use a GND on the Mary Avenue Bridge picture!  I used a technique that will be covered in an upcoming webinar on Photo Manipulation for the Night Photographer.  The very next webinar on photo manipulation is June 7, 2012.

Solar Filters

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Publish Date: April 9, 2012
Last updated May 29, 2017.

If you’re just now trying to get a solar filter for the upcoming total solar eclipse, hurry! Try a telescope store if there is one near you.  Trust me, most of them are sold out. PLEASE DO NOT attempt to photograph or observe the sun if you are not properly prepared. PERMANENT BLINDNESS or DAMAGE TO EQUIPMENT may result.

I  have been asked a lot about solar filters and why I was strongly encouraging people to get them. First let me explain how you might use them, then I’ll talk about the different kinds of solar filters and their costs.

Here are several shots of the sun rising behind Lick Observatory on Mount Hamilton, San Jose, CA. All shots are without any filter.

It Happened One Morning

The upper exposures are pretty conventional.  The exposures at the bottom, however, are clearly MUCH shorter and exhibit excessive flaring mostly due to IR light.  Indeed, here are the settings from upper left to lower right:

  • ISO 200, f/11, 1/80
  • ISO 200, f/11, 1/640
  • ISO 200, f/11, 1/8000
  • ISO 100, f/36, 1/2000

What is probably immediately obvious is the glare / flare and color fringing.  Compare the above shots to this one:

Rise and Shine [C_037951+77]

This is NOT a single shot, it’s a blend of two shots.  The thing to notice is how much better tamed the violently bright sun is. Another important consideration is that a solar filter provides a boatload of protection to both the eyes and the camera equipment more on that in a moment.  The bottom line is that the flare is well controlled and the sun exposure is sufficient that if there were a large sunspot on it, you’d be able to see it.

What Can I Do With A Solar Filter?

So glad you asked.  Consider these:

  1. Safely capture a Solar Eclipse prior totality.
    Why: Because it’s cool and solar eclipses visible from any given area are relatively rare.
  2. Safely capture the Transit of Venus on Tuesday, June 5, 2012.
    Why: Because this event won’t repeat for another 105 years! It’s rarer than Halley’s comet and it’s visible from everywhere in the continental United States. [Sorry your missed it!]
  3. Capture sunspot activity.
    Why: We are approaching the solar maximum where sunspots and coronal mass ejections are at their most active.
  4. Composite a nicely formed sun into your shots.  You can use my “Easy HDR” method described in a prior column.
  5. Seek solar alignments where the sun forms the back light to silhouette a foreground object.
  6. Catch the International Space Station (or other spacecraft) as it hurtles across the face of the sun.
  7. Use the solar filter as an “ultra stopper” to make extremely long daytime exposures of e.g. waterfalls or surf.

For some good background on how to observe an eclipse, see here.

Do I Need Protection?

For your eyes, absolutely. For your camera, HIGHLY recommended.  People often go “over the top” in their worry that a big lens will burn an instant hole in the sensor or camera body should they aim it at the sun. The image projected is onto a broad area at least as big as your sensor.  In a short period of time i.e. a 1/4,000 of a second exposure nothing horrible is likely to happen to the sensor at least. The combination of a mirror and shutter in a DSLR provides SOME protection to your camera and sensor from “certain doom” however if you were to ask my advice, I’d say DON’T use your camera to photograph the sun unless you have a SOLAR FILTER.  Most especially do not use live view (or a point and shoot camera) pointed at the sun. That tactic is very likely to damage your camera.

When I zoom in on the sun, isn’t that concentrating the light even more?

Well actually, just the opposite.  Instead of focusing all the energy on one spot, you’re spreading it over the sensor surface. So in fact, the sunlight is more concentrated when you don’t use a telephoto lens.

DO NOT look through the viewfinder to compose your shot unless you have a proper solar filter!  Permanent eye damage may result. Even then be careful.  And we just figured out that it’s not a good idea to use Live View to compose a shot.

What Kinds of Filters Are There? What Do They Cost?

Protection For Your Eyes

There are filters that you can wear or hold over your eyes. I highly recommend you get a pair. These are rated “ND 5”** and allow only 1/100,000 of the energy to pass through – they are effectively 16.6 f-stops of light reduction. Alternatively you can use a welders mask (though I bet not many of you have one!) #13 or greater.  Cost of wearable / simple filters ranges from $1 or so to $20 and more depending on the type.  Wearable filters are usually made of black polymer which blocks all wavelengths of light (important to prevent eye damage from non-visible light) and renders the sun a yellow-orange color.  Most locations only sell the personal filters in bulk (10 or 25 are the usual minimums).  I purchased a stock of 60, for example and have sold them all.

**IMPORTANT NOTE: There are at least FIVE different standards for measuring the transmissiveness of filters: “Neutral Density: ND, Optical Density – also often called OD, Shade Number – for welders glass, transmissiveness, and stops).  For a photographer who is familiar with the ND scale used to rate Neutral Density filters this is NOT the same scale as the “Optical Density” scale used to rate solar filters!  An ND3.8 (photo solar filter) in the optical density scale is equivalent to the ND8192 neutral density filter!  An ND8 filter for your camera is 3-stops of light. For safe visual viewing you need about 14 stops! So an ND8 is  woefully short of light snuffing capabilities. Moreover neutral density filters used with cameras may or may not extinguish harmful Infra-red and Ultraviolet radiation.  

  • What about using an 8-stop Vari-ND (ND2-400 Filter)?

At the maximum 8-stop setting (ND400) the filter is passing 0.4% of the sun’s energy.  That’s more than 40 times the recommended energy for PHOTOGRAPHIC use. A photo filter should transmit less than 0.01% (1/10,000). Even a 12-stop reduction in light (ND4096, Optical Density 3.6) may pass too much energy for safe and effective photographic use. 13-stops which is the same as Density 3.8 or ND8192 is preferable.

  • What about the “Big Stopper” by Lee or Hitech?

10-stops sounds like an impressive reduction in light but the resin filter (Hitech) passes quite a lot of IR and UV light. And 10-stops still really isn’t enough.  I haven’t see the response curve for the Big Stopper. It would be UNWISE to assume the Big Stopper or any filter is safe if it isn’t solar specific – especially if you plan to try to take more than a few shots. These filters certainly aren’t visually safe.

In addition to not reducing the light to safe levels, having an insufficient energy reduction means that you’ll have problems with flare / glare.

Photographic and Visual Filters

There are several varieties of solar filters that can be used for photography.

  • Black polymer screw-in solar filters – pre-made you order them to screw in on the end of your lens(es). There would be little point in getting such a filter for any lens that is less than about 200 mm effective focal length.  It might be worth making your own from an existing UV filter.
  • Black polymer “covers” or black polymer solar sheets from which you can make filters.
  • Silver solar mylar sheets (make your own) which render the sun a more natural white to a blueish cast. Mylar is less durable than polymer.
  • Glass solar Filters in a housing to fit over a lens hood or dew shield (ND 5.0)
  • ND 3.8 (Photographic) solar filters which are NOT suitable for visual observing.  This type generally only comes in sheet form and you must make your own filter. Not suitable for visual use because it allows too much of the suns energy to pass through to your eyes.
  • Tuned solar filters (also called Hydrogen Alpha) – like those found in the Coronado solar telescope. I don’t have a background in these, but normally you will need a set of filters and they are primarily designed for use with telescopes. The cost is upward of $600.

Normally when you buy a solar filter, you select a size that will cover your lens hood (or for a telescope the “dew shield”).  Fit on filters should be snug so that they cannot come off if bumped or buffeted by wind. You really do NOT want your eyesight destroyed by a gust of wind!  The filter should also seal out light leaks since most solar filters are reflective.

Filter Costs

Since the upcoming event(s) all require solar filters, they are in short supply. It may take literally MONTHS to get a filter from some suppliers.

Costs depend on the size and quality of the filter. For the average telephoto lens expect to pay from $60 to $100 for the glass type filters.  For very large lenses or for telescopes that cost could reach up to $200 and more.

Black polymer or silver mylar sheets will run you about $35 not including shipping.  The ND 3.8 Baader photo filter is about $90 for a 19 x 39″ sheet.  I also ordered a “natural color” Mylar polymer sheet (12″ x 12″) for about $30 from RainbowSymphony. RainbowSymphony also has the solar glasses at minimums of 25 pieces. Finding things on the RainbowSymphony site is a bit tedious. (NOTE These prices were as of May, 2012)

There are many references on the web for building your own solar filter if you choose not to buy a glass filter.

As with all things, quality varies quite a bit. I do not have the resources to exhaustively test all filters, but so far my best photographic results have come using the Baader Astrosolar Film (PHOTO) and hand made filters.  This filter passes enough light to keep the exposures fast at low ISOs and is optically superior to any other mylar or polymer material I’ve tried.  The glass (visually safe) filter I have darkens the image to make it visually safe and renders the sun an orange color (which it isn’t by the way).  Somewhat longer exposures are needed for this.

 

Resources

I’ve placed these in order according to my experience surfing and buying from the company.

Recommendations

If your goal is photos, get a Baader Astrosolar filter. It is not eye safe, but it does allow higher shutter speeds and versatility. Practically this means you’ll have to make your own filter from sheets as there are few resources with pre-made photo transmissiveness filters. Making your own filter is not that hard.

Second choice based on quality is a glass filter that seals well over your lens hood (you do have one, right?). The “outside diameter” of your lens hood must be about the same as or slightly smaller than the inside diameter of the glass filter you’ll put over it.  Since most glass filters are designed for visual use, you’re shutter speeds will be a bit slower but good quality glass will keep your photo sharp.

Get a pair of solar glasses for your eyes regardless of what else you do.

Easy (HDR) Blending with Stacking Software

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I’ve been teaching a “Catching the Moon” webinar approximately monthly. The focus of that course is to teach how to properly expose for the moon, how to catch the moon aligned with your favorite landmark, and how to determine the optimum light scenarios.  The webinar is based on my Alignment 1 and Alignment 2 articles with a healthy dose of additional material including some private material for students only.

One of the most difficult aspects of getting a moon alignment is that there is a pretty small optimum time window for getting an exposure.  Shooting earlier or later makes the foreground illumination and the moon illumination all but impossible to get both exposed properly in a single shot.

Here is an example of a single shot where the lighting was pretty close to perfect (though you can see the moon is a bit over exposed).

A Perfect 10 [5_057646]

However later that evening the sunset occurred quite a while before moon rise, so the sky and foreground were much darker.  The photographer faces a conundrum. Expose for the foreground or expose to preserve moon features.

On the left is a 30 second exposure prior to moon rise (though a tiny bit of the moon is in fact visible). On the right a 1/25th of a second exposure. Both taken on a tripod at f/9, ISO 250, 444mm effective focal length.  The problem is that a longer exposure renders the moon as a white featureless blob or streak (see below for an example). However exposing for the moon as on the right renders the foreground all but invisible.

What to Do?

There are a couple of simple alternatives. One is to bring both images into Photoshop. Make both images layers, the moon on top of the background and combine the two images using “Lighten” blending mode.  That will work very well and it’s essentially what happens when using the StarCircleAcademy Stacking Action. But that action, and even Photoshop are overkill for this situation.

Free Solution!

Fortunately Markus Enzweiler offers a free solution called StarStax that runs on Windows, Linux and Mac that makes it trivially simple to combine these two exposures – assuming they were taken on a tripod and the zoom, focus and direction does not change between shots.  StarStax is tailored to stacking star trails, but it does the same operation that Photoshop (and Image Stacker and StarTrails.de do).

And fortunately you can make it do a little more with almost no extra effort… as in this example. When the first image was taken it was quite dark and required a long exposure to capture foreground details.  Then all the moon images were taken with identical settings using an intervalometer.  It’s interesting to note how the moon darkens and deepens in color as it sinks in the atmosphere.

Project Impact [5_057573-615br]

So how do you create the simple or “stacked” motion images?  Easy.

 And here is the result.

Obviously to create a descending or ascending moon sequence you merely need to combine exposures taken at the appropriate interval. What is that interval? The moon travels roughly its diameter in two minutes. About 2 minutes, 14 seconds to be more precise.  I recommend taking exposures twice or four times as often as that, however and just use every-other or every fourth shot.

Since I took a simple approach to blend the images I also elected to go simple in presentation. Rather than fight the many different colors inherent in urban night scenes, I used Picasa3 to convert to monochrome, crop and frame the combined image – here using an earlier shot than the “Golf Ball on a Tee” shot above.

In the Evening [5_057775+92]

Here is one last example of a descending crescent moon combined using Photoshop. Here I didn’t wait a full moon diameter time between images because it was a crescent moon:

Mamma Glows, Baby Shines

 This also illustrates why taking more frequent exposures gives more creative latitude.