Canon 250D Close-up Lens

The Canon 250D close-up lens screws onto the front element of a standard lens to provide closer “macro” type photography.  In a way, the 250D is like a filter; in fact, that’s the first impression.  The 250D gets its name from the 250mm minimum focus distance from the front of the close-up lens to the subject when the standard lens is focused at infinity.  The 250D comes in 52mm and 58mm screw-in threads and is intended for use with standard lens focal lengths from 50 to 135mm.  in addition to the 250D, Canon also makes a 500D.

The 250D is a two element lens and is highly praised by its users.  Even so, instead of the 250D, I’ve used a (very) cheap set of close-up lenses for several years.  The cheap close-up lenses seem to be adequate for web and emailed images.  Because I plan to get the new G1X and the “macro” capabilities of the G1X appear to be severely limited, I decided to get the 250D to use with the G1X.

Getting a 250D turned out to be surprisingly difficult – or easy, depending on how you look at it.  My usual sources of supply did not have the 250D in stock or else showed the price to be over $200 so I turned in desperation to eBay and immediately found one from Tri State Camera for $99.  I was concerned about the authenticity of this “250D” but everything turned out fine. I did not like that the Tri State ad showed the 250D in a bubble pack but the unit I received was in a small box and included instructions.  It appears to be “Canon” to me.

While waiting for my G1X, I decided to use my G12 to do some sort of comparison between the cheap lens that I already have and the 250D.  Shown here is the 250D along with a +4 diopter and “10X” close-up lens.  The 250D is, more or less, like the +4 diopter lens.  As is always the case, before making the comparison, it is necessary to make up the “rules” for comparison. 

The rules for comparison of “macro” capabilities caused me considerable grief and still do.  For one thing, the G12 (remember, I don’t have the G1X yet) can focus down to about 1cm in macro mode at wide angle.  The problem at 1 cm is lighting.  I’m purposely showing a shadow here at about 1 cm distance using the G12 at maximum wide angle zoom but without any close-up lens.  Of course, the lighting problem can be worked around but my preference is to back off a bit and zoom in.   That’s why I use the +4 with the G12 and intend to use the 250D with the G1X.

I’m not saying that this is a great macro picture or representative of the 250D performance but with the 250D on the G12 and the G12 zoomed to maximum focal length, this is the relative image size.  Not quite as large as the bare G12 at maximum wide angle but the lighting is better.  (The cheap “10X” actually comes in a bit larger but the 10X image quality seems reduced to me.)

After my G1X arrives, I’ll eventually have more to say about the effectiveness of the 250D.

G9 Hyperfocal Chart

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Continuing the series on focusing the G9, knowledge of the hyperfocal distance is extremely useful when focusing any camera. Previous postings have included observations about the G9’s use of hyperfocal focusing and depth of field for closeups.

Somewhat loosely speaking, but easy to remember, is that if a camera is set for the hyperfocal distance then everything from that distance to infinity is acceptably in focus. In fact, everything from half that distance to infinity is in focus. For more details, check Wikipedia .

A most useful reference for both hyperfocal distance and depth of field is DOFMaster . Since both hyperfocal distance and depth of field vary with digital sensor size and focal length, here’s a chart of hyperfocal focusing distance specifically for the Canon G9 that was made by using the DOFMaster online calculations.


In addition to the hyperfocal distance, the table includes the near/far distance that is in focus when the G9 is focused at 10 feet. Why 10 feet? When the G9 is first turned on and switched to manual focus, it is set for (roughly) 10 feet.

Here’s an example of how the chart can be used. With your G9 turned off, set the Av mode at f5.6. Now turn the G9 on. The default focal length is the wide angle (7.4mm focal length) when the G9 comes on in Av mode. Immediately, switch to manual focus. You’ll see that the default focus distance is about 10 feet. Referring to the chart above for the 7.4mm lens, the hyperfocal length at an aperture of f5.6 is 5.3 feet. This means that, if the focus distance had been set for 5.3 feet then every distance from 2.65 feet (=5.3/2) to infinity would have been in focus. However, the default distance is 10 feet so everything from 3.5 feet (near focus) to infinity is in focus.

The G9 almost does not require focusing at the wide angle setting! But this happy situation changes dramatically at the longer focal lengths as shown in the chart.

Since aperture, focal length and manual focus distance can be saved as a custom setting (page 109 in the manual), the G9 can be preset for special situations -- including hyperfocal focusing.
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