Camera Lens

All posts tagged Camera Lens

Introduction to Lenses

Posted by JUST PhotographIN' on February 14, 2018
Posted in: Thoughts, Tips and Tricks. Tagged: , , , , , , , . Leave a comment

As I was beginning to get more serious about photography, I started asking other photographers for advice about equipment.  I looked at what they were using and tested out different camera bodies from different manufacturers.  There was one piece of advice that I heard several times: get good lenses (often referred to as glass).  I am glad I followed this advice, and have reciprocated the advice to other folks who ask me about equipment.

There are several reasons why I think it is important to get good quality glass.  The lens is what actually creates the image.  A high-end, expensive camera with the best sensor only captures what it is seeing through the glass that is placed in front of it.  Meaning, if the quality of the lens is poor, the image will be poor regardless of how good the sensor in the camera may be.

Lenses can have different specifications.  They can be wide-angle, normal, or telephoto.  This changes the perspective of what the lens can see.  Some lenses can zoom between focal lengths to change the angle of view more quickly without having to change the lens.  Other lenses have a fixed focal length (referred to as prime lenses). There are fast lenses and slow lenses, which is a reference to the aperture of the lens and how much light it will let pass through to the sensor.

Wide-angle lenses are lenses that see a greater angle of view from side to side.  They are lenses with focal lengths less than 50mm.  I have a 16-35mm super wide-angle zoom lens that I use for landscapes and astrophotography.  It is also a fast lens with a f/2.8 aperture that lets in a lot of light for low light situations.

Normal lenses are typically 50-85mm.  These are good for portrait photography.  I do not take many portraits.  However, I know a lot of portrait photographers who use something in this range.  People are rendered nicely by these focal lengths.

Telephoto lenses are going to range anywhere between 70-400mm.  I use a 70-200mm zoom lens for portrait work as well as some wildlife and landscape photography.  This is my go to lens if I want to carry one lens that will cover a wide range of possible distances.  I tend to get more questions with this lens, as well.  Longer lenses tend to attract more attention.

Speaking of longer lenses, the final category is the super telephoto, which is basically anything 400mm or higher.  These lenses are great for wildlife and sports.  They are probably the most recognizable lenses out there due to their size.  People often migrate toward me when I have my 400mm f/5.6 lens on.  They are intrigued to ask what I am shooting or make a comment like: “I wish I had that camera (they really mean lens).”

Last year, I added a spotting scope to my lenses.  It is a 1250mm focal length, f/10 aperture, Celestron C5 spotting scope.  Again, people migrate toward me when I am using this lens.  It is unique for photography, and offers a slightly different perspective.

Lenses impact the photographs that can be created.  My challenge for this week is: take a look at the lens.  Find out what the technical specifications are: what is the focal length of the lens?  What is the aperture range?  Is it a prime lens or zoom lens?  Next week, I will be going more in depth about aperture with a video to demonstrate how it works.

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What is the Subject?

Posted by JUST PhotographIN' on February 7, 2018
Posted in: Thoughts, Tips and Tricks. Tagged: , , , , , . 1 Comment

Today, I want to talk about the subject of photographs, and why it is important to pick one.  Sometimes, subjects are easy to pick.  Other times, they are more difficult to see.  They can be any number of things: wildlife, flowers, people, landscapes, objects, specific events, etc..

What is the subject of these photos?

I think it is easy to say that a Red Fox is the subject.

Back in February of 2016, I made a trip to Yellowstone National Park to observe wildlife and view the scenery.  My main objective was to observe wolves in their natural habitat, which I was able to accomplish.  There are photographs that document this experience.  However, the Red Fox photographs are more intriguing to me, because the subject stands out.

When I look at these two photographs, it is easy for me to identify what I am looking at.  This is an important tip for photography.  Having a clear idea of what the subject of a photograph is helps make other decisions about how to make the photograph.  I used a telephoto lens on a cropped frame camera to capture the above photographs of the Red Fox.  This is due to the distance required to maintain safety of persons and animals.

One of my favorite lenses is my macro lens.  This is great for capturing close ups of flowers, such as this pasque flower.

However, I would not recommend using a macro lens for wildlife photography.  The subjects are not the same, and they require different equipment to capture them properly.  Vice versa, I do not try to capture macro moments with my telephoto lens. Honestly, this is something I observe a lot of people doing.

Knowing what the subject is also helps define how to interact with it.  As I mentioned above, wildlife need distance.  Flowers do not.  Therefore, the interaction is different.  If the subject is people, maybe the interaction is more casual or formal.  Capturing this moment on a family vacation was a casual experience, and I think the photograph depicts that.

Interacting with the subject is part of the experience of creating the photograph.  This is why it is important to know what the subject of the photograph is.  I am continually learning more about wildlife, flowers, and people that I photograph.

Having a defined subject helps create better photographs.  It helps answer other questions that I will dive deeper into in future posts.  What is the subject of the photograph?  Ponder this question during the week.

 

Spotting Scope Photography

Posted by JUST PhotographIN' on March 22, 2017
Posted in: Thoughts. Tagged: , , , , , , , , , , . 3 Comments

On Monday, I took my new Celestron C5 spotting scope out to view a nesting Great Horned Owl.  The scope kit comes with a standard eye piece for optical viewing.  However, they also offer an adapter that allows a camera to mount to the scope for use as a super telephoto lens.  This was my main objective when I bought the scope.

Monday was my first time setting up the scope with the camera mounted on it.  There are some technical details to take into consideration when photographing with a long focal length.  I also use a 400mm lens that has similar issues, although not as exaggerated.

File Mar 22, 12 13 22

This is looking into the front of the Celestron C5 spotting scope.  The technical specs are shown around the perimeter: focal length of 1250mm with an aperture of f/10 making the primary mirror diameter 127mm.  There is also no image stabilization.

File Mar 22, 13 54 52

The owls have nested around this location for several years.  I setup the scope with the eye piece to get the scope pointed at the right location.  Then, removed the eye piece and attached the camera on the adapter.

File Mar 22, 12 35 03

The above photo is with the camera on “live view” mode.  I ran into a few issues with live view.  First, there was glare from the ambient light on the screen.  Second, in order to view anything on the screen, I had to adjust the shutter speed to a  much longer exposure than was required for the actual exposure.  I am guessing this is due to the camera not having the aperture information to calculate the overall exposure when displaying the image on the screen.  The camera is more than likely reading the light within the scope itself, which is much darker than the ambient light within the scene.

As I mentioned in the technical information about the scope, the aperture is fixed at f/10.  This means I am controlling the exposure with adjustments to shutter speed and ISO.  The general rule of thumb to freeze camera motion is to use a shutter speed equivalent to or greater than the focal length.  In this case, that means faster than 1/1250th of a second.  This is where having a camera with good high ISO performance comes in handy.  It turns out that the rule of thumb of placing ISO and shutter speed equivalent to each other gave me the proper exposure for the scene.  I went with ISO 1600 and shutter speed of 1/1600 at the fixed aperture of f/10 provided from the scope.

This may sound like over kill.  Yes, I could have used ISO 1250 and shutter speed of 1/1250.  However, there was a slight breeze which added motion to everything, and I wanted to make sure I was getting the fastest shutter speed to freeze the motion as much as possible.  This is not talking about the owl movement, which would have been frozen at a much slower shutter speed of possibly down to 1/500th or slower (since she was not moving that much).  I am strictly speaking about the subtle shake in the camera setup on the scope.

Eyes On

This is the resulting image.  There are a few more tricks to reduce camera shake.  I already mentioned one of them above: shoot with live view.  Live view inherently locks the mirror up which reduces the “mirror slap” that occurs during a normal exposure.  The camera also has a mirror lock up function, which is the mode I ultimately used to take the photos.  Mirror lock up requires a double press of the shutter release button.  The first press locks the mirror up.  The second exposes the image.

There are drawbacks to this, as the timing of events in the scene may change by the time the photo is exposed.  I did not time the actual sequence, but I am guessing there was around a two second delay between the first shutter click and the second shutter click to allow for the shake to minimize from the mirror flipping up.

Owl Blink

After the mirror flips up, I can no longer visibly see what is in the view finder.  This means things can change in the time it takes to hit the shutter to expose the image.  For example, when I started the process for this image, the owls eyes were open.  By the time I hit the shutter to expose the image, she was blinking.  It was an odd coincidence to capture this moment.  Had I seen her blink, it would have been too late to capture the moment, due to the delay from the mirror locking up and hitting the shutter release the second time to expose the image.

This can be reduced by shooting the images with live view.  However, the exposure setting to view anything on the screen was not appropriate for the exposure of the scene.  This resulted in a blank image full of white pixels since everything was overexposed.  Again, I am unsure if this is due to the camera not having the aperture information to assist with calculating the exposure to display on the screen.  Canon EF lenses communicate aperture information with the camera body.

Lastly, I was also using a remote trigger for the shutter release.  This allowed for hands free operation of the camera to further reduce motion of the camera.  Using the shutter release button on the camera requires a press which in turn induces motion into the setup.  The remote shutter release removes this induced motion.

At any rate, I was thrilled with the results from my first attempt to use the Canon 5DIII mounted on the Celestron C5 spotting scope!  I am looking forward to more trips out into the field with the setup.  I am sure I will get more familiar with the intricacy of shooting with the setup.

How much is too much?

Posted by JUST PhotographIN' on July 15, 2013
Posted in: Geeky. Tagged: , , , . 1 Comment

Of course, photography requires equipment [gear or gadgets]!  With different photographic subjects comes a list of required and optional gear.  How much is too much?

My main drive for photography has been to explore the natural world around me.  That includes landscapes, wildlife and wildflowers.  My macro lens can focus at 11.92 inches from the focal plane giving a one to one life size image of the subject.  On the other end of the spectrum is my wide angle lens that gives almost a 90 degree angle of view.  All of this equipment is great for each specific situation.

I have been observing a lot of wildlife and have been trying to photograph them with my 70-200mm lens.  What I find is that even with a 2x extender [making the lens a 140-400mm], it is difficult to fill the frame with the subject.  Either I do not want to get that close, or the subject does not want me that close.  This has me thinking that it may be a requirement to eventually add a 400mm lens to my collection.  The other option may be to add a cropped frame camera and continue to use the same lenses [glass] that I already have.  The advantage to this option is that I can get an increased focal length for a somewhat cheaper expense than adding the lens.  Canon cropped frame cameras have a 1.6x increase in focal length to compensate for the difference in full frame glass.  This means that the 70-200mm lens becomes a 112-320mm lens.  Either way, I think another piece of equipment may be in my future.

Along the same lines of another lens comes the issue of multiple subjects for photographing.  Even some landscapes, wildlife and wildflowers are difficult to photograph under natural lighting.  Most of the time natural light works, but there are situations where a flash can give an added pop to make a subject stand out.  Most of the time a flash is used for portrait photography.

Back at the beginning of the month, I was experimenting with portrait photography at Vacation Bible School at church.  I do not currently have a flash.  Some of the events were inside with very poor light.  In order to get decent photos, I was bumping the ISO up which meant post processing to reduce noise.  Some of the events were outside with very bright sun.  It would have been nice to have a flash in both situations.  Inside, I was not able to get a fast shutter speed to stop motion without out introducing noise from a high ISO, or I would have an underexposed image.  Outside, I needed a little bit of fill light to reduce some of the contrast between light and shadow areas.  A flash can be a handy tool to manage light in many situations, and I can see that this may be a piece of equipment I add to my collection [possibly sooner than later].

There are plenty of other pieces of equipment that are on my list.  I am also certain that I may find things that I never thought of that will end up in my collection.  It is just a matter of how much is too much!