Tag Archives: focusing

Street Photography

Hyperfocal Distance – Street Photography Part 3

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Street Photography Series

  1. Previous Attempts
  2. Zone Focusing
  3. Hyperfocal Distance
  4. Progress?
  5. Tips and Tricks from the Web

Hyperfocal Distance

The hyperfocal distance is the focus point for any given focal length and aperture combination which gives the largest possible depth of field. Basically zone focus with the biggest possible zone.


How to Find It

Hyperfocal distance can be calculated using an online calculator, or an application such as Photobuddy. Another option (I did this before I got Photobuddy) is to write them down, because the only variables are focal length and aperture you can write down the hyperfocal distance for the most common focal lengths you will use, and each aperture. For example, if I am going shooting with my Pentax M 28mm lens, I know the focal length will be 28mm, and I know I won’t be shooting wide apertures without focusing on the subject itself. So what I can do is calculate and write down the hyperfocal distance at f5.6, f8.0, f11.0 and f16.0 as a small reference. The other option you have is to use the DOF scale on your lens (if it has one). This link has a good picture to show how to use the scale to set to hyperfocal distance.

Here is my example hyperfocal chart for a K200D with a 28mm lens (you probably dont actually need near limit written down, but it can be helpful – it is always half of the hyperfocal distance)

  • f5.6 – 6.96m – near limit 3.48m
  • f8.0 – 4.93m – near limit 2.465m
  • f11.0 – 3.49m – near limit 1.745m
  • f16.0 – 2.48m – near limit 1.24m

Applying Hyperfocal To Street Photography

To apply this method of focusing to your street photography is much like zone focusing. When you calculate your hyperfocal distance, you will know the near limit of acceptable focus. Once you know this, and can judge that distance, you can photograph anything which is at least that far away from you without having to focus on it. All you need to do is set your lens/body to the appropriate f-stop, focal length, and focus distance then start taking shots.

I will post up my results with this technique in the few days. I am waiting for the temps to drop, its been over 30 degrees C here all week!

Macro

Macro Photography Techniques – Part 3

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The 3rd installment of the series will cover the use of extension tubes. Again this is a method which requires an extra piece of equipment, but again it is something which can often be acquired quite cheaply.

Macro Photography Techniques

  1. Close Focus Lens
  2. Teleconverters
  3. Extension Tubes
  4. Reversed Lenses
  5. Macro Lens
  6. Combining Techniques
  7. Close Up Filters

Extension Tubes with a Fast Lens

First off, lets talk about what extension tubes are. Extension tubes are a simple device which mounts between the camera body and the lens. They contain no optical elements (where a teleconverter does). All they do is modify the register distance (distance from the lens to the sensor or film plane) which means the minimum focus distance of the lens becomes much less, as does the maximum focus distance for that matter. You can no longer focus to infinity with a lens mounted on extension tubes. Moving the lens further from the sensor or film plane also results in a loss of light. This is why I recommend using a fast lens when using extension tubes. The exact amount of light you will lose will depend on the thickness of the tubes (or how far from the sensor plane you move the lens).

Types of Tubes

There are 2 main types of extension tubes. There are those which operate the lens’ aperture mechanism, and those which do not. The most commonly found is the type that do not. These are often sold very cheaply on ebay, and come in 5 parts. A body mount, a lens mount, and 3 extensions of various sizes. These work just fine, however, if you want to stop the lens down (and you will, to get more depth of field) these can become quite hard to use. If you stop down the lens, you will notice the view finder darkens significantly, to the point where focusing, and even just composition of a shot becomes hard or even impossible.

I recommend spending a little extra on your extension tubes, and getting the “Auto” type. This means that the extension tubes allow the camera body to still operate the lens aperture through the tubes. This allows you to focus/compose the shot with the lens wide open (as happens with the lens mounted normally) and then the body closes the aperture just as the shot is taken. I have a set of these extension tubes, made by Vivitar for Pentax K mount.

Bellows?

Bellows, what are they? Bellows are basically a very large, length adjustable extension tube. They allow for heaps of magnification, but are heavy and awkward to use. I have not personally used a set of bellows, nor do I see myself using a set of bellows as I like to be mobile. However, keep them in mind.

Which Lens

As mentioned earlier, I recommend using a fast lens which extension tubes, as it allows you to focus and compose more easily after you have lost light from the tubes themselves. Something to keep in mind is, the shorter the focal length of the lens, the more magnification you get from an extension tube. For example, my extension tubes are sized as follows; 12mm, 20mm and 36mm. If I use the largest tube (36mm) with my 50mm lens, I get extra magnification, but if I use the same tube with my 28mm lens, I will get greater than 1:1 magnification! A good approximate rule is, to get 1:1 use the same length of extension tubes as the focal length of the lens. This guideline only applies to lenses which are not extremely close focusing already (like the CZ Flektogon 35mm f2.4 which already focuses to 1:2 magnification, 35mm of tubes will get greater than 1:1 on this lens).

I have successfully used my 50mm f1.7 lens, 50mm f2.0 lens and 28mm f2.8 lens with extension tubes.

Focusing

As before, focusing is best achieved by moving yourself and the camera and lens closer to, and further away from the subject as required, rather than using the focusing ring. See Part 1 for a full description.

Results

Here are some photos taken using my extension tubes. Dont forget to share yours in the comments

50mm f1.7 lens, all 3 extension tubes, ISO 100, 1/180 sec, f11.0, onboard flash. These are aphids, the big one is an ant.

 

50mm f1.7 lens, 36mm extension tube, ISO 100, 1/180 sec, f11.0, onboard flash
Macro

Macro Photography Techniques – Part 2

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This is the 2nd technique I’ve used when taking macro photos (also the one I’ve used the most).

Macro Photography Techniques

  1. Close Focus Lens
  2. Teleconverters
  3. Extension Tubes
  4. Reversed Lenses
  5. Macro Lens
  6. Combining Techniques
  7. Close Up Filters

Teleconverter with a Close Focus Lens

This technique requires a teleconverter. A teleconverter is an accessory which mounts between your camera and your lens. The effect is increase of focal length. In this case you will probably want a 2x Teleconverter, which is designed to double the effective focal length of your lens. However it does not change the minimum focus distance, so you end up with the same lens, focusing at the same distance, but you get twice the magnification of the image. You can also get Macro Focusing Teleconverters (such as this) which have their own focusing ring, and allow extra magnification, and a good level of control over the magnification.

Drawbacks? Of Course…

The downside of this technique is that a 2x teleconverter, while doubling your effective focal length, it also reduces the effective aperture (incoming light) by 2 stops. So if your kit lens happens to be a Pentax SMC DA 18-55mm f3.5-5.6, and you are wanting to get maximum magnification (55mm @ minimum focus distance) adding a 2x teleconverter will mean that the lens (wide open, where it is a bit softer) becomes 110mm at f11.2. So in order to get a fast shutter speed you will need either high ISO (noisy) or a flash. I have had very good success just using the onboard flash though.

A teleconverter will also exaggerate any quality problems in the lens you are using. If you lens is a bit soft, it will be twice as soft using the 2x teleconverter. So you must be cautious about how you use it. This is where using a flash is also helpful, as it allows you to use a smaller aperture, which will mean the lens is going to be closer to its sweet spot for sharpness.

Another obvious drawback is that you need an extra piece of equipment. I was able to acquire an older 2x teleconverter to fit Pentax K mount on ebay for about $15. It has no “A” contacts (for camera autoexposure) or autofocus. Ideally you would want to have the “A” contacts for auto exposure, however, auto focusing is not required for this technique as you will be using manual focus mode set to minimum focus distance anyway.

Focusing

The same method for focusing is used as for the previous technique. You can read up on that here, in Part 1.

Results

Here are a couple of photos taken using this technique, including settings.

SMC F 35-70mm @ 70mm (effective 140mm), f11 (effective f22), 1/180 sec, ISO 200, onboard flash
SMC F 35-70mm @ 70mm (effective 140mm), f16 (effective f32), 1/20 sec (this should be shorter), ISO 400, onboard flash
SMC F 35-70mm @ 70mm (effective 140mm), f11 (effective f22), 1/180 sec, ISO 200, onboard flash

For those of you who already have teleconverters, why not give this technique a try, and post up the results in the comments.

Macro

Macro Photography Techniques – Part 1

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This is the start of a series of posts on Macro Photography Techniques which I have successfully used. Each part will be a different technique. Feel free to add any ideas you have as comments, and also to post your macro’s if you have used the techniques before, or after you go and try it!

Macro Photography Techniques

  1. Close Focus Lens
  2. Teleconverters
  3. Extension Tubes
  4. Reversed Lenses
  5. Macro Lens
  6. Combining Techniques
  7. Close Up Filters


The Close Focus Lens

The first technique in the series will be the most obvious one, a close focus lens. A close focus lens is a lens which focuses quite closely, but is not a true macro lens. For example, the Pentax standard kit lens is the SMC DA 18-55mm f3.5-5.6. This lens focuses down to 25cm, which (at 55mm focal length, fully zoomed in) gives a reproduction ratio of around 1:2.9. A true macro lens will allow focusing down to a 1:1 ratio (older Macro lesnes are actually only 1:2). Even with 1 of these types of lenses some great macro shots can be created. Most DSLR owners will have a close focusing lens as most kit lenses are close focusing so its a technique anyone can try (and most would have).

Getting The Most From It – Focusing

The key with a close focus lens is being able to focus on something, with the sensor plane as close as possible to the subject. You need to make sure you are at that minimum focusing distance when you take the shot to get the maximum possible magnification from your lens. The easiest way to do that, is to set your camera (or lens, depending on model) to manual focus, and set the focus manually to the minimum focus distance. Once you have done that, all you need to do is to get nice and close to your subject, and focus by moving the camera (and probably yourself too) further away from, or closer to the subject as required. This will mean you get the maximum magnification because the lens is pre-set to the closest possible focus point. By moving the camera you move the subject into the correct distance and into focus.

This is the focusing technique I use for all my macro photography, so will apply across this whole post series. To help you achieve correct focus most cameras will have a focus confirmation of some kind, even in manual focus mode. Pentax cameras have a focus confirmation beep (which can be disabled) as well as a green hexagon displayed in the view finder once focus is confirmed. However, when using manual focus only the centre focus point can be used, so you must point the centre of the frame at the subject while focusing.

Depth Of Field – It’s Too Narrow!

With macro photography narrow depth of field can become an issue. When you are so close to your subject, and have a longish focal length, it will cause your depth of field to become very narrow. The only way to increase it is to use a smaller aperture (larger f number, eg f22). This will make your shots very dark, or your shutter speeds very long. To overcome this, you could use a flash. An off camera flash is preferred, but the on camera flash can work just fine too, especially with a reflector (I’ll explain that in a later post).

What this means for you, is (as always) the photo becomes a balancing act between shutter speed (fast to avoid blur), aperture (small to get the DOF you want) and ISO (low to avoid noise).

The Results

Here are a few shots I have taken using this method. Including the settings used.

SMC M 28mm f2.8 @ min. focus + cropped – ISO 100, 1/100 sec, f4.0 (from memory)
Tokina RMC 70-210mm f3.5 @ 210mm min. focus + cropped, ISO 200, 1/640 sec, f3.5

Time to get out and take some macros. Don’t forget to post the results in the comments section. Stay tuned for the rest of the posts in this series.