Tag Archives: weather

UV Filter for Protection!?

I see the question asked a lot. Should I get a UV filter to prevent my (expensive) lens from being damaged should something bad happen? Or “the salesperson told me I’d get better photos if I used a UV filter.”

In a nutshell my answers are no and wrong.  The thinking that a $25, $50 or $150 piece of glass in front of a $1,000 lens is going to somehow protect the lens element from harm seems a bit absurd except in a very few scenarios which I’ll address in a moment.  Moreover, to assume that a thousand dollar lens’ image quality will be improved by a filter is unlikely.

Here are some of the arguments for NOT using a filter (clear, UV or any other for that matter).

  1. A filter creates another surface that may cause additional flare, glare or reflection.
  2. For all but the most perfectly polished and coated filters, optical degradation is certain with a filter.
  3. Filters can introduce color casts and vignetting.
  4. Putting a thinner shatterable piece of glass in front of a lens provides a source of sharp shards with which to to scratch the front lens element.
  5. Those who leave a filter on all the time often find their protection becomes unremovable preventing them from using a more useful filter like a polarizer or neutral density filter.

But… That Filter Might Save My Bacon!

Think about it. In what scenario will a filter protect the lens? A blow by a golf ball, baseball or softball? Nah, a direct blow will shatter the filter and drive shards of glass into the front element.  A drop onto the floor, lens first? Maybe. The filter holder may provide a little extra protection to the lens barrel, but again, when the glass filter shatters you’ve got shards of sharp up against your expensive glass.  What about a fall onto a rock?  Yep, a filter might help a little, but a lens hood would help a lot more – as would a lens cap.

Block UV rays

What about the argument that a UV filter will “block UV rays” and improve the contrast and exposure?  That is part true – if you’re shooting film. DSLRs are far less sensitive to UV light than film and that filter is more likely to become a source of glare, flare, internal reflection and vignetting.  That UV filter is also yet another expense and item to carry around.

When Does it Make Sense to use a UV/Clear Filter?

If you have burning metal or corrosive substances flying at your camera, I would certainly prefer that they strike a cheap(ish) piece of replaceable glass rather than my expensive lens. Also, some lenses are only well sealed against rain and dust if you put a filter on them. So an excessively wet, dusty or sandy environment might be a good candidate for filter use.

Under Fire [C_041883]

What Do I Do to Protect My Lens?

Aside from being careful, I would argue that using a lens hood is an almost ideal solution. A lens hood helps keep things away from the front element and it also serves the important additional photographically USEFUL function of keeping off-axis light out of your shot. Off-axis light can cause significant glare and flare and attendant loss of contrast.  Even the best filters are little or no help with off-axis light.

My personal policy is also to “cap the lens” whenever  I am not shooting and definitely before I move anywhere. The cap stays accessible in my back pocket and it goes on the camera before I move it. Much like my seatbelt is always fastened before I start the car.

Oh the Weather Outside is Frightful – or Not

Published: May 18, 2012
Updated: May 3, 2016

One of the necessary tools a night (or landscape) photographer must have in their tool bag is a decent weather forecasting tool.  Though I’ve been known to ignore the forecast for some events, like an Annular Solar Eclipse, I definitely am more inclined to go where the weather is clearer (Nevada) than where it will be cloudy (Crescent City, CA).

A forecast like this despite how detailed it seems to be is all but useless to me:

Weather.com forecast

Weather.com forecast

This is the hourly forecast. The “daily forecast” is less helpful. How partly is partly cloudy? And how mostly is mostly cloudly? Other sites sometimes just say “sunny” during the day and give no idea what night will be like.  Compare the above with the Weather.gov forecast from NOAA.

NOAA to the Rescue (no Ark)

Fortunately the US National Weather Service provides a nicely detailed “click point” forecast with charts of the hour-by-hour conditions.

Weather.gov oh yeah.

Weather.gov oh yeah.

There is quite a lot to take in here but it’s all good stuff.  The “partly cloudy” at 7PM  shows as 72% cloudy (Sky Cover) on weather.gov. Not only are the forecasts different, but I get more useful numbers.  It looks like the wind will be very gusty during parts of the day. But the humidity won’t be so severe that dew will form.  If it weren’t for the mostly cloudy skies, night photography might work out ok.

Where do you find this great tool. Start here:  http://weather.gov

Once you get to the forecast, look for a small graphic on the right under “Additional Resources”.  But that, my friend, is where the good stuff is. Before you rush off on the hourly thing, though, take a look at the little map window.

Weather.gov forecast area highlighed in green.

Weather.gov forecast area highlighed in green.

You can get a forecast for any specific area by clicking on the map!  So, for example clicking on the summit of Mission Peak (just off the screen to the north) may give you a significantly different forecast – one that is adjusted for the difference caused by altitude.

Do remember that these are “forecasts” not actualities, so be prepared for whatever may happen.

Wunderground Classic

I used to use Weather Underground. Then they changed it so that the good stuff was only in “Classic”. But really, no need to use it at all any more.

May the wind not be at your back or in your face, may the road not be muddied by rain and may the clouds gather only when you really want them i.e. at sunrise and sunset.

Star Circle Planning Tools in The Field

In early September, I discussed the four essential tools for planning a star circle or star trail shot. Briefly recapping, those are:

  1. Google Maps (or other mapping software preferably with roads and terrain maps).
  2. An ephemeris
  3. An Inclinometer
  4. A GPS Unit – very useful for finding a location as well as finding north (if your unit has a compass built in, that is).

In this article I am expanding on those basic items and I am about to tell you where most of these tools reside… wait for it… my iPhone. Trust me I am no great gusher of “all things Apple”. My co-workers have been defecting to the Mac platform while I have been cursing myself for sticking it out with Windows 7 and all of the bizarre behaviors that came with it.

But my iPhone is an indispensable tool for me. I use it much more onsite than for pre-planning, but the apps are very useful nonetheless. Can you do this stuff with a netbook? Probably. Android phone? Most likely. But I do not have those and I have come to love my *first generation* iPhone. Yep. Still first generation.  Sure I could grab my wife’s former G3 model since she’s moved on to an iPhone 4… but my iPhone feels quite comfortable to me because it is set up just how I like it.

My indispensable apps in approximate order of their value to me are as follows:

  1. Words With Friends $3 – or get the free version  (App Store, website)
    I have to do something to pass the time while the camera is clicking away. This is for playing scrabble with folks. Requires a data connection through wifi or carrier. Was VERY buggy, but stability has improved. I am usually playing 10 to 15 games at a time.
  2. Clinometer (for iPhone / iPod or iPad) $1  (App Store, website)
    Probably my most useful application. I use this onsite to measure angles from the horizon. I can determine if the North Star will be visible, and how close or far to get from a foreground object to have the north star where I want it. I start the app, sight along the long edge of the iPhone and read the angle on the display.   I can scout during the day and get just what I expect when it gets dark. I will cover this very useful tool in more detail in an an upcoming column as well as the next workshop.
  3. Starmap $12 or Starmap Pro $19  (App Store – regular, pro).
    I bought the regular version even though I knew the pro version was coming out. Great planetarium app with dates and locations for meteor showers of every description, sun, moon and planetary data, constellations and the ability to customize the display to match your viewing conditions. My main gripe is that it uses only “common” names for the constellations. I know the latin names (I much prefer Orion to “The Hunter”). Has a good “find it” feature and you can set it for different dates and times and locations. Very handy for navigating the night sky.
  4. Photo Buddy $2 (App Store, website)
    It is overkill for what I use it for which is primarily: calculating the hyperfocal distance, and calculating the angle of view. It will also calculate depth of field and has a sunrise and sunset function. There is a very wide selection of cameras and models which makes configuring it pretty easy even if the interface is just a bit clunky.
  5. Focalware $5 (App Store)
    I do not use this as much, but it will calculate sunrise, moon rise, sunset, moonset and altitude and azimuth for each. It needs a signal to determine your location or you can enter GPS coordinates.  There is a very advanced version of a similar app called Helios which sells for $30 – if they had it for the moon it would probably be worth the price.
  6. iCSC free. International Clear Sky Chart –
    Predicts visibility on an hour by hour basis for the next 24 hour period. Widely used by astronomers and usually very accurate. Covers most of the continental US and Canada.
  7. Safari (builtin) Sometimes you have to look something up on the internet… if the internet is available, that is.
  8. Flashlight (free). (App Store)
    This app is a bit clunky, but you can use it for light painting and once when my headlamp broke it was very adequate as a “flashlight” substitute since it can be set to any color or luminosity.
  9. Built in Camera (free)
    The old iPhone has no zoom so it is possible to measure angular dimension with just the camera display. It also comes in handy for grabbing quick shots of possible shooting locations. Admittedly the G3 version with built in location info would be better for this.
  10. TPE [The Photographer’s Ephemeris]  $9 (App Store, website)
    Sadly, since this app requires a data or wifi connection to be useful, and since the screen real estate is so tiny, I find this a less useful substitute for the free version which you can use on your laptop or desktop machine (Mac or PC). An iPad version is available which provides much more real-estate to work with. Haven’t tried that version yet, however. A new feature has been added which seems very interesting (finding WHEN the moon or sun will be in the direction you want)… but I haven’t used it yet.
    If you’d like to learn how to use TPE, there are many resources available, including a tutorial I did:  Using The Photographer’s Ephemeris
  11. TideApp (free)  (App store)
    When photographing along the coast it is very helpful to know when and how high the tides will be.  There are not many tidal stations and finding the closest and most accurate one is not easy… but it sure is handy when you need it.  Hint: if you want tides along the Pacific Coast do not pick stations that are inside of bays, rivers or estuaries.