the evenings out here - Thoughts, rants and musings about absolutely everything except photography. Or cats.

How deep is your DOF

I really need to know

in General Rants , Tuesday, November 20, 2012

The Bee Gees must have been prescient when they wrote “cause we’re living in a world of fools”, because they we didn’t have internet photo nerd forums back in the 70s (we had flares - much better). If there is one thing guaranteed to wind me up most in those wastelands of joined-up thinking it is when some dweeb starts whining, posturing or proclaiming that such and such camera and/or lens doesn’t have “enough DOF”. DOF, of course, meaning Depth Of Field, but all the evidence tends to indicate that 90% of the aforementioned dweebs don’t know that. Back in the 70s (well, ok, 90s as far as I’m concerned), “enough DOF” meant being able to get a significant amount of your scene in focus. And it wasn’t easy, with 100 ISO (film, that is) being considered fast!

Canon cap snow

DOF porn Exhibit 1. Almost certainly (a) the first intentional picture of DOF I ever took, and (b) the least interesting and most pointless photo ever made in Antarctica. Canon FTb, 50mm f/1.8

In dweeb-land, however, “DOF” means getting as much of your photo out of focus as possible, preferably rendering everything in a pretty swirly smoothy hazy way so as to make the subject - usually a brick wall, or their back garden - totally unrecognisable. And it gets much, much worse when you run up against a Full Frame Cultist, who will inform you, in no uncertain terms, and with no room for discussion, that His (they’re always male) Way is The One Truth. You absolutely cannot get enough “DOF” (or indeed resolution, sensitivity, you name it), with, horror of horrors, a (micro) four-thirds sensor. Well, I beg to differ.

Drm 2012 11 16 EP31744

DOF porn Exhibit 2. Only a camera geek could love it. Panasonic Lumix 25mm f/1.4

And oh do I wish I find out where to get all that extraneous DOF four-thirds sensors apparently suffer from. Then I’d be able to get the jumbled bunches of rocks I like to photograph all in focus!

All systems, pretty much, allow you to be creative with shallow depth of field. It’s all down to focal length and positioning. Sure, there are certain configurations that are easier, or perhaps only possible, with a given lens on a full frame sensor. But exactly the same can be said for other combinations. Within reason, and excluding extreme edge cases, you can pretty much achieve whatever effect you want with any camera system. It just requires less talk, and more thought.

Of course, in 95% of cases normal people neither like nor see the point of these photos. They’re not photos of anything, just “tests” to show what “great DOF” Lens X can do. Fantastic. There are a few exceptions, but actually using this effect in a truly creative and rewarding way is very, very hard.

Extreme lenses, such as the Leica Noctilux f0.95, were designed for low-light shooting, not “DOF”. I can’t imagine trying to actually focus a Noctilux on a rangefinder! These days, with digital cameras giving good performance at ISO levels beyond film’s wildest dreams, these ultra-fast lenses are even more niche items. Typically, in the Film Age, lenses designed for soft-focus backgrounds were short teles with maximum apertures in the f/2 to f/2.8 range. Which, strangely enough, in terms of “equivalent separation”, is exactly where the Panasonic Summilux f/1.4, which I just bought in a fit of futile retail therapy, sits. And don’t let any forum troll tell you different.


Site update

New commenting and other exciting stuff!

in Site Admin , Wednesday, October 03, 2012

I have just made a whole series of behind-the-scenes changes to, which I hope will make it more interesting and more attractive to use.

First of all, commenting. I get quite a lot of comments here. Almost all are spam or borderline spam. Since I moderate everything, they don’t get through. But they do get through the ghastly CAPTCHA. And it means an unfortunate delay for legitimate comments. I could allow comments from members only, but however much I try even my few regulars refuse to sign up, although several hundred did when I ran the site on Movable Type. Possibly I’ve screwed up the template, or possibly nobody can be bothered. But well over a 1000 spammers did manage to register themselves… Unfortunately Expression Engine insists on its member-based approach, and I can’t even seem to “whitelist” regulars allowing them to bypass moderation. In my opinion it’s a real weak area in EE. So I’m going to go with the flow, and try out Disqus comments. From now on all commenting passes through Disqus. Old comments will still be visible, but the Expression Engine commenting interface is turned off. We’ll see how it goes. Of course, this makes “logging on” here pretty pointless for now. But maybe I’ll add some members-only stuff in the future. Who knows.

Next, and starting with this entry, I’m going to try to ressucitate the “Other Stuff” part of this site by restarting the dormant “The evenings out here” blog. It has been raised to full peer status with “photoblogography”, and gets its own seperate tag cloud.  T.E.O.H, to use the short name, has in the past been a repository for general writing, sometimes about music, sometimes general geekery, sometimes about work related stuff. Well, there won’t be much work stuff, as anything writing about anything vaguely interesting I’m doing would be a criminal offence. So it’s going to be more general. I’ve left all the old articles up, but a lot of them are extremly outdated these days. But I still find some of the more unbalanced ranting vaguely musing.

I decided to go with this revival after considering what some of my favourite blogs are doing - such as Patrick LaRoque, Rob Boyer - and also others who seem to go from total zero to fully accomplished guru in two years! I decided finally that my split personality “photography & other stuff” theme was basically my unique “selling” point, so the best thing I can do is to emphasise it. On the photography side, I’m also not so good at the more “photoblog” kind of very regular publishing. I’m more into (self)-curated galleries these days.

Obviously running this site has to fit somewhere in my leisure time, and there’s little of that to go around. I’m also pretty slow at writing articles, although I’ve usually got a least a handful floating around in my head.

Anyway, I hope all the new stuff works, and I apologise for the inevitable bugs. I’d be delighted if you left a comment (unless it involves an incredible business opportunity buying Viagra from Nigeria).


iExpression test

So many tests, so little time

in iPhone , Wednesday, June 22, 2011

Just a little test post from iExpression, with a photo attached to make it less boring


Internet Explorer negative margin bug

filters are not your friends

in web design , Friday, December 17, 2010

I think this is worth mentioning: I spent the better part of today trying to fix a layout bug in Internet Explorer 7, where a negative margin was applied to a floated image container. The image was cut off at the edge of the containing element.


This is actually a well known-bug - in theory - and a reliable fix is to add a “position: relative” CSS rule to the floated container.  But it didn’t work.

After a lot of research and tearing out of hair, followed by careful debugging (aka “wildly flailing about”), I discovered the reason.  The containing element had a Internet Explorer proprietary filter applied to it, to give a semi-transparent fill:

  filter:progid:DXImageTransform.Microsoft.gradient(startColorstr=#59000000, endColorstr=#59000000);
/* For IE 8*/
  -ms-filter: “progid:DXImageTransform.Microsoft.gradient(startColorstr=#59000000, endColorstr=#59000000)”;
border: none;

On removing this, everything worked perfectly.  So I just used a semi-transparent PNG as a fill image instead.  Probably more efficient anyway.



All a Twitter: good read

At least I can admit when I’m wrong. Sometimes.

in Technical Book Reviews , Monday, July 27, 2009

My previous post displayed me at my sarcastic best, with a cheap jibe at a book I hadn’t actually read. When I actually started reading the book, I soon discovered this…

This Book Is Written in More Than 140 Characters

Yes, I’ve heard that joke. I’ve heard it often. If you are at a book signing and are thinking of asking me, “So is this book written in more than 140 characters?”, please reconsider. The fact that this book is as thick as it is and has thirteen chapters should be the hint that there is a bit more to Twitter than you might expect.

And just tonight, as I was writing this, someone cracked that joke. So, please, don’t make that joke. It’s just not working for me anymore. Thank you in advance.

...and felt suitably embarrassed.

Well, the case for the defence rests on the fact that there is an awful amount of new-agey, geeky, shallow idiocy written about Twitter - amazingly, not all of if by Tim O’Bookshifter - and I just expected this to be another bloated hagiography. Well, I was wrong.

“All a Twitter” is actually rather good. Tee Morris explains the mechanics of Twitter as a web application, and critically examines various tools you can get hold of to enhance your experience. But beyond that it takes a reasoned, balanced view of the “why” of Twitter, and encourages readers to decide for themselves what benefit they could get by joining in - or not.

You may think that Twitter is something that young people today waste their time on, or you may think that it is the biggest revolution in personal communication, like, EVER. Or you may think that it is a healthy social lifeline for the millions of people who spend their waking hours, at work or at play, in front of a computer screen.

You may also be turned off by the crass levels of self-promotion which various public and insider figures have indulged themselves in. Well, the author deals with them, gloves off, and makes it clear that their egocentric behaviour reflects themselves, not the wider community.

Personally, I’m still not sure if Twitter is for me - and especially vice-versa, but I’m better informed now than I was on Friday. Wherever you stand, if you’re at all interested in this social phenomenon, “All a Twitter” is a remarkably interesting, well written and thought provoking book that deserves a wide audience.

And yeah, it’s written in more than 140 characters.


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