Tuesday, May 21, 2019

Clarity - also called mid tone contrast.

Cascade Falls, Mission.  Left:  low clarity   Right:  high clarity
I drove out to Cascade Falls yesterday with a friend of mine.  It was a wet, soggy day with little promise of blue skies.  Uncertain of what weather lay ahead, but determined to overcome whatever was thrown at us, we proceeded stout-heartedly towards our goal.  The truth is I considered whimping out a couple of times but was persuaded by my sodden-proof friend that such was the life of explorers.  So, we made our journey to the falls' parking lot where we donned what rain resistant gear we had and began our trek.

If you have never been to Cascade falls it is well worth the trip.  The round trip to the site really only takes fifteen minutes or so, and the trail is well established.  No mud and little in the way of foot entanglements.  The area is cordoned off so that anyone attempting to access the river will be thwarted by well maintained chain link fences.  Only those willing to scurry over or under them can make it there; the slope and river itself is very dangerous and staying on the walkway is highly recommended.

I got off a number of shots.  The above one was taken with a Panasonic bridge camera with an ISO of 80, a shutter speed of 1/25th of a second and an aperture of f/2.8.  The wet weather produced a low contrast scene.  I typically use a RAW camera setting and did so here as well.  I post processed in Photoshop CS 6.

If you look carefully at both images you will notice that they are, in fact, one and the same.  The same file was used to produce both images.  The difference between them is that the left one had a clarity setting of around -35 and the right one had a setting of around +18.  Mid-tone contrast, also called clarity, is a setting which alters the contrast of middle-value tones.  There are typically three tone ranges.  Highlights are the brighter values, shadows are darker values, and mid-tone are the values in between.  

Altering mid-tone contrast has a number of benefits.  Lowering it gives the image a decidedly softer feel.  I use low values in portraits and in places where I want to take the harshness off surfaces and edges.  In places where the scene would benefit from better definition and distinctive surfaces I use positive values.  Look at the waterfalls carefully.  You will notice the left one is much softer and the water appears almost misty.  The right one appears more like a thunderous avalanche of water.  I prefer the left one.

Not all editing programs offer the ability to change mid-tone contrast.  Photoshop and Elements both have it.  If this is a feature that is important to you, consider looking to see if what you have, or hope to acquire, does.

Thanks for reading.    www.ericspix.com

Thursday, May 9, 2019

Use of a polarizer filter.

Dike at end of 216 St, Maple Ridge.  Left:  no polarizer   Right:  polarizer used
If you are at all like me, winter has not encouraged you to take many photographs.  With spring fully entrenched and summer lurking around the corner, you leave your ensconcement seeking sun and fresh air.  You find yourself outdoors.  Beauty abounds.  The landscape unfolds before you; blue sky meets forest and water.  It is time for the camera to come out.  Before you run out ready for action, you should make sure the battery is charged and you have a memory card in it with lots of room.

Out with camera in hand, you snap a few shots.  They look pretty good, although it seems a little less brilliant than the way you think it should be.  The colours are not as vivacious as they could be though, and they seem to off somehow.  Right beside you, a friend has the exact same camera, and all the settings are exactly the same (amazing); the only difference they are using a polarizer filter (since polarizers are grey in colour they actually reduce the light coming into the camera, so your friend's settings would be a bit different, but close).  You compare images - wow!  Look at the difference between the two shots!

It was, of course, the polarizer which did it.  I have discussed polarizers before (click here), but a brief review is in order.  Polarizers take out light which has been polarized along some plane.  Rotating the filter changes which plane it removes polarized light from.  It turns out light from open sky is very blue; it is also polarized light.  Used correctly, the polarizer will take all that extra blue light out of your image.  The result gives truer colours and better contrast. 

The trick with polarizers is to know when they will help.  They tend to be ineffectual on a cloudy day, although they will still help with reflections off surfaces, including water.  On sunny days they take the blue tint out of shadows and darken blue skies.  They will not darken all skies however; much of that depends on the time of day and the direction you are shooting relative to the sun.  You get the best results when the sun is behind you and not straight overhead. 

If you get a polarizer, try this:  Go out on a bright sunny day, mid-morning is fine.  View the sky and landscape with your camera.  Rotate ring on the the polarizer filter 180 degrees.  Change your position by rotating yourself to get a different part of the scene in the viewfinder and repeat with the polarizer.  Move, rotate, move, etc.  Pay close attention to how the polarizer affects the image.  You will notice that the polarizer makes the most difference when the sun is behind you but off to the side.  Do the same thing at noon and then later in the afternoon. 

I try to be careful with polarizers when using ultra-wide angle lenses, or when doing panoramas.  Since they perform differently depending on your angle to the sun, they will cause your resulting shots to be unbalanced.  I often remove polarizers when doing this type of photo, when using flash, and when shooting in low light.

Have fun, and keep on shooting.  www.ericspix.com

Thursday, April 25, 2019

Using perspective and skew in Photoshop.

Left:  Church before correction    Right: Church after correction
Have a look at the above images.  The exposures are one and the same.  The difference between them occurs after the file has been accessed by photoshop.  What are the differences, why do they matter, and how did I do them?

The image was taken off center, mostly because it was a better position to shoot from and I captured more of the flowers on the left side of the door (you can see them if you look carefully).  Shooting it off center caused the roof line to appear at an angle.  I used the skew command in Photoshop to line this up parallel to the top of the frame.

With height comes a reduction in the width of any building, which is why the church's tower is smaller at the bottom than the top.  This is the normal effect of perspective.  You can use a PC (perspective control) lens to correct it in camera, or use a bellows with the ability to angle the lens; something present on some large format cameras.  My solution was much more economical.  Use the perspective control in Photoshop to widen the top of the image.  It worked fine.

The problem this produces though is that it makes the church appear squat because now the width is the same all the way up but the height is wrong for the proportions.  For this I used the distortion command and lengthened the whole image, stretching the church.  The downside to this is that everything gets stretched, not just the upper part of the church.  If there was a way to stretch the image proportionally, with none at the bottom and an increasing amount over the height of the image, the effect would be much better.  However, it works well for the most part.  This is why the image on the left is shorter than the image on the right.

Finally, there was the issue of the missing corner.  When the skew command was issued the upper right part of the image became barren as no image data was available for it.  Fortunately, the missing section was only sky and it was a simple matter of using the clone tool to patch up that part of the photo.  I think the corrected version looks much better than the original.  What is your opinion?

Monday, April 22, 2019

The making of a monster.

If the monster was to talk, what would it say?
We were at Coombs market yesterday.  Its most renowned feature is the fact that it has a grass roof which hosts goats during the summer.  The whole area is perfect for the eclectic shopper.  As usual, I was packing a camera and discovered an unexpected subject; a one-eyed monster tree.  The original picture, unedited, is on the left.

That was the picture my mind saw the moment it popped into my visual field.  It only needed a second eye, which I knew Photoshop could address.  After bringing the image back to my computer, thought became a reality.  That's the image on the right.  Now I needed a caption.

That's one of the fun thing about interesting photos.  The meaning or effect of an image can change completely with the right words.  Consider some of the possibilities:

  "Squirrel!"
  "That's E-N-T, not A-N-T."
  "Keep that dog away from me!"
  "That was a tasty kite, Charlie Brown."
  "My roots!  Where are my roots?"
  "... and the green grass grew all around, all around, and the green grass grew all around."
  "OK goat, just a little closer to the edge."

If you think of a caption, won't you please attach it as a comment.  Thank you.

Saturday, April 20, 2019

Bowen park waterfalls and a neutral density filter

Bowen Park Waterfalls, Nanaimo
A neutral density filter is a grey filter, completely neutral in colour, which attaches to the front of your camera lens.  Its sole purpose is to allow you to use slower shutter speeds than what you would otherwise be able to.  You would not make use of one normally, as shutter speeds are often slow enough as it is.  Most people don't have one, or may even not know about their existence.

The top image was taken early in the morning without an ND filter.  The exposure time was 0.3 seconds.  This is slow enough to allow some blurring of the water's movements.  It produces a pleasant effect.  The bottom photograph was shot using a neutral density filter; the aperture and focus points are exactly the same.  The shutter speed is significantly slower though, being a full 20 seconds.

The difference is subtle, although I prefer the longer shutter speed over the shorter one.  I love how the rocks and moss in the stream stand out from the blurred water.

I have a confession.  The camera I used was a 1-inch sensor bridge camera; a Panasonic FZ2500 camera which comes equipped with a virtual neutral density filter.  A small switch on the side of the camera reduces the amount of light hitting the sensor, allowing you to shoot slower shutter speeds.  The switch was set to the 1/64 value - a 6 stop reduction in light.  If you take the 20 second exposure from the bottom image and divide it by the 0.3 second exposure from the top, you get 66.7 - close enough to the 64 times light reduction.

I have a variable neutral density filter which I use on my DSLR lenses.  It does the same thing, although it has the disadvantage of putting extra glass between my subject and the sensor plus being an extra thing to buy and carry to boot.  I have to admit to liking the sliding switch feature on the all-in-one camera though. 


Tuesday, March 26, 2019

Benched in Tortuga

Top:  bench in Tortuga  Bottom:  Kathryn on the same bench
When I see something that appeals to me visually, I want to photograph it.  I loved the scene facing us (top) while visiting Tortuga last year.  It was colourful, had clean lines, and was simple yet attractive.  It was populated with simple objects each of us takes for granted.  To top it all off there was an easy way to compose the image, facilitating the rule of thirds and framing.

Clearly though, something was missing.  The large open space to the left of the window was begging for a subject; anything really.  It was a gaping hole in an otherwise wonderful setting.  The solution was to incorporate a person, and I knew the very one.  One of the things I frequently do is to photograph something without someone in it, then repeat the process but this time with a person.  The change was dramatic.

Although the same void existed, there was now a dominate subject which displaced its presence (bottom).  Instead of the eye finding an empty quadrant, it found a person.  This deflected your attention in such a way as to change the entire composition.  The great news here is that it is an easy fix.  It accomplishes the goals of changing the anchor point in the image and adds a personal touch.  The reality is that the top photo would mean less to me over time while the bottom one would forever carry the image of one I love.  How poignant. 

This idea then is the basis of this blog.  Shoot as you see fit, but remember to put people in your shot some of the times.  Photographs of things or places will always carry with them a certain degree of appeal or nostalgia, but it is the people in our lives that gives them perpetual meaning.  Selfies are, of course, all the rage, but often leave out important methods of producing fetching photos.  A tripod, a little time, and some instructions on your part will likely produce far more rewarding images with you as the centerpiece, along with whoever accompanies you.  I suggest taking two shots, one with people and one without.  Compare them over time; the one with family and friends will almost certainly become the most favourite over time. 

Thanks for reading this.            www.ericspix.com


Saturday, March 23, 2019

Flash and the beauty of no synch speed.

Top:  no flash was used.  Bottom:  built-in flash used.
I have spoken on the merits of fill flash, and will likely do it again because of how much it improves an image, even when its use is not mandatory.  Today I want to talk about the difference in using a DSLR camera which is limited by something called a flash synch speed and using a non-SLR-type camera which is not.  Normally I would sing the praises of the DSLR because of the larger sensor and the ability of it to take accessories such as other lenses and external flashes.  This is one place where non-SLR cameras have an advantage.

To understand what a flash synch speed is, you first have to comprehend why it even exists.  DSLR cameras use a mechanical shutter to allow the camera's sensor to be exposed.  It is a physical mechanism which opens and closes using "curtains", which block light when present in front of the sensor.  When a photo is taken, the first curtain travels across the sensor plane leaving the senor open for an exposure to take place.  The first curtain remains open until the exposure is complete, then the second curtain moves and finishes off the job.

They travel independently of each other as long as the shutter speed is at or below the flash synch speed.   This tends to be between 1/180th to 1/250th of a second, with most cameras using 1/200th of a second.  At shutter speeds faster than the flash synch speed, the shutters move in tandem, the space between them guided by the shutter speed.  Faster shutter speeds require that the two shutters are closer together.  To see a video on this, click here.

The problem starts when flash is used.  At shutter speeds at or below the flash synch speed there is no problem because the entire shutter is open.  At speeds above this, only a portion of the shutter is open at any moment and the flash will illuminate only a portion of the image.  To prevent this your camera will limit the shutter speed when the flash is popped up or an external one is attached.  If you use an off-camera flash which is not dedicated, the camera will not be aware of a flash.  This means you can go above the flash synch speed, but with a consequence.

Enter non-DSLR cameras.  Compacts usually use non-mechanical shutters.  They are electronic in nature and use no moving parts.  They do not have a flash synch speed and so higher shutter speeds can be used in situations involving flash.  This is where the photos above come in.

Both shots are done with an ISO of 80, an aperture of f/3, and a shutter speed of 1/1000 of a second.  The top photo is not an issue as no flash was used.  The bottom image does involve flash, however.  The camera was a bridge camera; it is an all-in-one camera that uses an electronic shutter instead of a mechanical one.  A shutter speed of 1/1000 of a second is not a problem.  The question you may have at this point is, "So what?   Why is it a problem?"

The short answer is aperture.  It was very bright, and the shutter speed of 1/1000 of a second allowed me to use the low aperture of f/3.  This means the flash can further and impact shadows a greater distance from the camera.  With a shutter speed of 1/200th of a second, my minimum aperture would have been around f/7.  Light travels less than half the distance at that aperture, and it is likely there would not be enough of it to properly illuminate the scene.  The built-in flash of a DSLR camera would not be able to work to its full potential because of the limitations of flash synch speed.  There are two ways around this though.  One is to use an external flash on a DSLR or to use a feature called high flash synch speed, which is not available on all cameras.