Author Archive


Sunday, March 20th, 2011 by

An old shot, from my hiking trip through Scotland in 2005.

Technical details

Shot on my Miranda MS2 Super, with its original kit zoom, on Kodak HD200 color print film.

Why I like it

Mostly, I like the sign.

Photography formulas – Macro

Thursday, February 10th, 2011 by

Recently I was doing some research regarding calculations for close-focus photography. Since I didn’t come across a place that collected all the relevant formulas (aside from a few forum posts), I thought I’d compile them a bit.

F: Focal length
X: Extension
D: Focused distance (measured from the lens nodal point)
P: Focused distance (measured from the film plane)
M: Magnification
B: Bellows factor
O: Object size
I: Image size (size of O on film)

Focal length, extension and distance

First, the relationship between focal length, extension and distance. Extension is how far the nodal point of the lens is from the film plane. Note that this is at least the focal length of the lens1. An extension of F gives you infinity focus, more extension gets you closer.

\frac{1}{F} = \frac{1}{X} + \frac{1}{D}


Magnification is the relationship between the size of the subject, and the size it will be on film. With a magnification of 1, a 10mm subject will be 10mm on the film. Note that for macro lenses, magnification is often given in the form 1:(1/M), so a magnification of 0.5 would be 1:2, and life-size would be 1:1. magnifications bigger than 1 will have the bigger number in front, so a magnification of 2 would be 2:1.

M = \frac{X}{F} - 1 = \frac{F}{D-F} = \frac{I}{O}

Note that you can invert this to find how small an item you can photograph with a given magnification. Using a 1:2 lens on 35mm film will allow you to photograph a scene of 72mm wide and 48mm high, for example.

Bellows factor

Bellows factor determines how much extra exposure is needed when photographing close to the camera2. Multiply the `normal’ exposure of the scene by the bellows factor to get the correct exposure.

B = (\frac{X}{F})^2 = (\frac{I}{O} + 1)^2 = (M + 1)^2

Note that this only applies if you are using a camera without TTL metering. A TTL meter will automatically correct for this.

Some examples

Say I have a 135mm lens, that normally focusses down to 0.9 meters from the lens. The maximum magnification is then:

M = \frac{F}{D-F} = \frac{135}{900-135} = \frac{135}{765} = 0.18

I can calculate the lens extension at closest focus:

\frac{1}{X} = \frac{1}{F} - \frac{1}{D} = \frac{1}{135} - \frac{1}{900} = \frac{1}{159} \Rightarrow X = 159

If I add a 25mm extension ring between the lens and the camera, I can calculate the new magnification at infinity:

M = \frac{X}{F} - 1 = \frac{135 + 25}{135} - 1 = 0.19

And the new magnification at closest focus:

M = \frac{X}{F} - 1 = \frac{159 + 25}{135} - 1 = 0.36

So with the extension ring, the lens becomes capable of roughly 1:3 macro.

If I were using a camera without TTL metering, I’d have to calculate the new exposure:

B = (M + 1)^2 = 1.36^2 = 1.85

So I’d have to add about two-thirds of a stop to the exposure my meter sees in order to get a correctly exposed picture.

Without the macro ring, at closest focus the bellows factor would be:

B = (\frac{X}{F})^2 = (\frac{159}{135})^2 = 1.39

Which would be roughly one-third of a stop.

You can see that bellows factor doesn’t really become an issue until you get at 1:2 magnification or greater, from which point is increases very quickly.

It’s worth to note that the distance scales on most lenses indicate distance from the film plane, not from the focal point of the lens. This makes the calculations a lot more complex, as

P = D + X

which converts the first formula above to:

\frac{1}{F} = \frac{1}{X} + \frac{1}{P - X}

Imagine the lens mentioned above doen’t focus 0.9 meters from the lens, but from the film plane. It’s now not as easy to determine X. Rewriting the formula above, we get a quadratic formula:

-X^2 + PX - FP = 0

which our math teacher taught us means that:

X = \frac{-P \pm \sqrt{b^2 - 4 \cdot -1  \cdot -FP}}{-2}

And thus:

X = 165

from there on, we can use the formulas above to determine magnification, bellows factor and everything else as normal.

Note that the quadratic formula also gives us

X = 735

which is another extension that would give a subject to film-plane distance of 0.9 meters, though that would take us very solidly into macro territory, with a magnification of:

M = \frac{X}{F} - 1 = \frac{735}{135} - 1 = 4.44

In other words: Well over four times life-size, and the exact reciprocal of the magnification at 165mm.
This is logical, since

735 = 900 - 165

This is simply the entire optical system reversed, with the subject and film switching places.

  1. Telephoto and retrofocus lens designs can be shorter or longer than their own focal length, but they `cast’ a nodal point outside (or behind) themselves, as it were []
  2. Due to the inverse square law, the further you rack out your lens, the less light hits the film/sensor []

Playing games

Wednesday, January 5th, 2011 by

A shot from last october, part of my family playing a board game. This was an emotional evening, as we’d just heard that my mother had come through a very complex surgery succesfully.

Technical details

Leica M3, 21mm Super-Angulon, Neopan 400, developed in Rodinal 1:45

Why I like it

I just works for me. The diagonal of the arm, the pose of my sister-in-law on the left, the depth of the image without excessive `wide angle distortion’.


Tuesday, January 4th, 2011 by

Well, I unpacked the enlarger, taped a few bin-liners to the windows and experimented a bit.

I used some old paper that was packed in with the enlarger and trays (making it at least 25 years old, probably well past 30), developed in Rodinal (the only suitable developer I had, since 30 year old developer is probably even more of a crapshoot than 30 year old paper), used a water stop and my normal fixer.

Note that this is a bad scan from an office copier. The actual print is much sharper and has no banding.

As you can see, the paper was heavily fogged1, but the image is still recognizable. Considering that I pretty much winged both exposure and development, and this is the second print I made (ever), I’m actually pretty satisfied.

Specs: Neopan 400@320, Rodinal 1:50; Ilford Ilfospeed #3, Rodinal 1:25

I just ordered some fresh paper and a proper paper developer. More to come…

  1. Interesting detail: The paper was probably older than the girl in the picture []

Looking back: 2010

Monday, January 3rd, 2011 by

Last januari, I wrote about my goals for the year. Time to look back and see what got of them.

My goals were:

  • Shoot at least 3 pictures I consider good enough to enlarge to at least 30×45 cm. One of those should be B&W.
  • Shoot at least 50 rolls of film.
  • Set up a place were I can print B&W pictures, and learn to do that.

Let’s start with the second one: 50 rolls. I shot 48 rolls during the year, and had two almost complete rolls in my cameras, both of which I completed on New Year’s day. I think that counts as 50. I finished one of the rolls shooting fireworks at midnight (and immediately shot the first full roll of 2011).

The third one, set up a darkroom and learn to use it, was not so successful. The home renovation project took much longer than initially expected, and I only got to the darkroom late in december. The good news is that I spent this weekend moving in my parents’ old darkroom equipment. I still have to light-proof the room, but after that I can get some chemicals and paper and start experimenting. So, not completed, but well underway.

Finally, the first goal. Shoot 3 pictures good enough to enlarge and frame them. This one I simply don’t know yet. I haven’t completely caught up with my scanning after the move, and haven’t looked very deeply into all my negatives, even the ones I did scan.

I do know I shot one of the most important pictures of my life this year, which already got enlarged and framed. So that’s one. (I’ll write more about it in a future post). The other two, time will tell once the darkroom is finished.

Aside from the goals, 2010 was a pretty uneventful year. Most of the pictures I shot were simple shots documenting the rebuilding of our house, and much of the rest was filled with pictures of my family and other snapshots. I also shot my second wedding.

Equipment-wise, I fell in love with the Leica system, completed a nice camera/lens set, and started selling off some Canon equipment that became superfluous. The Leica set is finished now, I plan to write about the different parts in the coming months.

On my way back

Thursday, December 16th, 2010 by

A quick update:

I’ve finally gotten around to fixing my PC, and my study is all set up, including my film scanner. So hopefully I’ll be able to post some new pictures before the new year.

More excuses

Thursday, August 26th, 2010 by

And another post explaining a lack of posts.

My PC died earlier this week. Since my laptop died a few months ago, I’m am now unable to get to my digital pictures (though they are all safely backed up), and am unable to scan my films.

Parts are on the way for repairs, so after moving day (next saturday) I’ll have to find my soldering iron between all the boxes, and hopefully I’ll be able to post something before long.

The end of the Leica Year…or not?

Tuesday, August 10th, 2010 by

August the 10th. It is now a year ago I started with Michael Johnston’s ‘Leica Lessons‘ project.

I feel like I didn’t really complete the year, though. As I detailed before, I’ve been using my 400D occasionally to record the progress of our renovation project1, and as you can see from last week’s picture, I haven’t stuck to one lens either. I’ve also started using a light meter during the second half of the year2.

So, will I ditch the Leica tomorrow and go back to my EOS 30, or even run back to the modern embrace of digital? No, definitely not. I’ve found that for most of the things I shoot, the Leica is close to my perfect camera. It’s small, so I can carry it always, it’s reliable, and it’s an enormous pleasure to use. It certainly has its weaknesses, and rangefinders don’t suit every purpose, but nothing prevents me from using one of my SLRs if the need arises.

As I mentioned earlier, I haven’t really stuck with one lens. When I realized the Leica was there to stay, I started drawing up my ultimate Leica kit3, and started watching Ebay for deals on these lenses. Over the past few months, I’ve been able to get both lenses I wanted for very reasonable prices. I haven’t used the lenses much, mostly put a few rolls behind then to make sure they worked as they should, but I still used them. They have, however, confimed my assessment that the Leica suits me.

Why did I start using a lightmeter? This I blame on the remodelling project: Because I had very little time to shoot, and equally little time to develop, I practised little, and there was often a long time between shooting the picture and seeing the result. It is also my experience that you need to keep excersizing the skill, or it will fade very fast. When I started getting less than 10 well-exposed shots per roll it started taking the fun out of the whole project, which wasn’t the idea. So I picked up a Leicameter MR from Ebay, and I’ve been using it for most of my shots since then. That, combined with the fact that I’ve finally zeroed in on a exposure index/developing combo I’m happy with means that the last 5 months have given me a lot more satisfying shots.

So, what’s next? I might, in the future, redo parts of the year, since I feel like I cheated. I’ll certainly give GSOTPANWASTOTZSS another go, when I can make more time. I’ll also keep shooting a lot of B&W film. For one thing, I like the ability to do your own development, but I also feel like I haven’t learned everything I can about shooting in B&W yet. I will be trying out the Leica (or more exactly, the Leica lenses) with some colour slide film though4.

Next friday I’ll be shooting another wedding, so I’ll get a healthy dose of modern cameras and lenses. Let’s call it detox.

  1. I was also asked to shoot a swimming match a few months ago, for which I brought the Canon as well. []
  2. Though to be fair, this requirement wasn’t stipulated by Michael Johnston, but by me []
  3. On which more in a following post []
  4. If I like both, there may be a second body in the future, though that won’t be soon. []

Fish ladder

Thursday, August 5th, 2010 by

Just a quick picture to show I’m not dead yet.

Shot two weeks ago in the east of the Netherlands, a close up of a fish ladder. A little experiment with shapes and close-ups.

Technical details

Leica M3, 135mm Tele-Elmar, Neopan 400, developed in Rodinal 1:45


Tuesday, February 16th, 2010 by

Ok, let me explain.

As may be obvious from my lack of posts, I’ve been busy.

Fact is, December last year, F. and I bought ourselves a house. It’s a moderately old house (1948), and we are practically the second owners (the previous owners bought it from the housing developer halfway though the 1950’s, we don’t know if it was lived in before that), so, understandably, there was (is) some work to be done on the house. It is (was) in reasonably good shape, just very outdated. We knew this from the start, and were planning on some intensive renovations. Which is what I (we) have been doing the past two months (and probably will be doing for the next few as well). We’ve pretty much stripped the house of all its insides, leaving only the walls and beams standing, and are currently in the process of putting back all the wiring1 and plumbing2, as well as renovating the bathroom, adding an upstairs toilet, insulating the house better, etc.

To make time for this, I’ve started working extra hours during the week, giving me an extra day in the weekend, which I spend working in the house, meaning my spare time has been reduced to a close proximity of zero.

Lack of spare time equals a similar lack of time to go out shooting pictures, or update this website3. The fact that my darkroom equipment is already in a box also doesn’t help.

In a related event, F. indicated she would like to have some pictures of the renovations that weren’t in black & white. Combined with the fact that tearing out the entire electric system meant lighting in the new house is slightly limited, and that a 50mm isn’t exactly designed for photographing small rooms, this made me invoke my escape clause for the Leica Lessons project, and so I’ve taken the 400D out of storage, together with my 17-40L and 580EXII. These pictures aren’t exactly interesting to anyone but us, so I doubt any of them will be published here. If I might find time, I’ll try to post some older pictures here over the following months, but don’t expect too much updates. Hopefully, after the move I’ll be a bit more diligent with my postings4.

On positive news: One of the things I’ll be doing in the new house is furnishing one room to be used as (among other things) a darkroom.

  1. The electricity was heavily outdated, and damaged, part of the pipes transmitting current, and the whole system was much too small for a modern set of appliances. []
  2. Also outdated, as well as laid out in a very impractical manner. []
  3. There you have it, my explanation. []
  4. I’ll be living much closer to work, so I’ll have roughly 2 hours more spare time each day. []