Macro Pinhole

One of things that draws people to pinhole photography is the ‘infinite depth of field’ that the medium is able to capture.  A lot of people assume that this means that everything in the composition, from the pinhole to infinity will be sharp.  Unfortunately this is not quite the case.  I researched this in quite a bit of depth for my Masters degree, but the general consensus is that if you have the optimum sized pinhole for your cameras focal length, then everything from 20 x your cameras focal length should have reasonable sharpness.

For instance.  You have made or converted a pinhole camera, and its focal length is 50mm.  Most online calculators will tell you that the optimum pinhole size for 50mm is around 0.3mm, give or take a few 0.01mms.

I have found this to be correct and with my 50mm cameras I use the 0.3mm laser pinholes made by James at Reality So Subtle and have no issues with them.

Your camera now has the optimum sized pinhole for its 50mm focal length and so the maths says that everything more than 1000mm away from the pinhole (50mm focal length multiplied by 20) should be of optimum sharpness.

This maths does start to fall apart though in my experience once you start looking at parts of your image that are a very long way away, but thats for another post.

Anyway the point of this post was to talk about a little experiment I tried a few days back.  I’m sure I’ve mentioned it before, but the guys at the Sunny 16 Podcast run a bit of fun called the Cheap Shots Challenge.  Each round has a specific ‘genre’ of photography and the idea is that you use the same cheap film camera for each round, and then the submitted images are judged by the guys and usually a guest.  This time around the genre was bloody macro, and of course my cheap shots camera is a pinhole camera…

Hence my ramble about how subjects too close to the pinhole are not in focus and therefore pinhole cameras are shit for macro…

So what to do about that.  Well unless I can find someway of altering the way light and physics work…(one day Neil)…the only thing to do is to incorporate a lens of some kind.  I don’t know if that’s frowned upon within the pinhole community or not.  And actually, I couldn’t care less if it is. 

I came across one of those crappy little lenses the other day that are designed to go over your mobile phone camera lens and are supposed to let you shoot fish-eye, wide and, yup, macro on your phone.

I tried looking through it at something really close and it seemed to work ok but I didn’t really know how it would perform on a camera, especially over a pinhole, so I tried it on the front of a pinhole body cap on my digital camera.  Yes I have one of those kicking about…it’s a Canon 600d if you’re interested. 

The principle seemed to work, very well in fact.  I did seem to be able to focus pretty well on subjects that were just a few centimetres from the pinhole.  So I made a very sophisticated coupling system that allowed my to securely attached the lens to my Zenit TTL pinhole conversation (Blue-Tac) and set off to find something interesting to photograph.

Well. Flowers. Macro always starts with flowers doesn’t it? They’re interesting and normally fairly common. Mine had to be static, indoor flowers as my exposure times were running five or ten minutes in some cases. 
And thats really about all there was to it to be honest.  I used the Pinhole Assist app as I would normally – again I cannot say enough good stuff about this app, and told it that I was using the Zenit, which is pre-saved in the app, and that I was using Ilford FP4, again, pre-saved with reciprocity failure rates, and away I went.

Some images worked well, some not so well.  I think the ones where I was too close didn’t come out so good.  Below are my favourites.

Oh yeah one last thing.  I mentioned above that they were taken using Ilford FP4.  Thats not incorrect and yes its a black and white film.  The colour that you can see is the result of scanning the black and white negs as they actual colour they are.  Just so you know, and just in case you care. I hope you care, I mean you’ve made it to the end of the post…?!

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FP4+

Until now I have been using whatever film (within reason) came to hand out of my fridge. I have a dedicated fridge that is full of film that I have acquired over the past two years or so, and for black and white work I have mainly been using Ilford FP4, SFX and HP5+.
I wanted some consistency with the film that I use and had narrowed my favourite down to HP5 and FP4. I am getting low on both, and the rolls that I have of each stock are either almost expired or I am unsure how they have been kept before I got them. Or both. I have had good results with both films but I made the decision to stock up on FP4+ rather than HP5. I have achieved good results in the past both pushing and pulling both stocks of film – rating the film at an either higher or lower ISO to compensate for ambient light levels and developing accordingly – but I chose FP4 because natively it is an ISO125 film. For my pinhole work the lower ISO is more appropriate, and if I am not using it in a pinhole camera and I need to I can rate it at anything up ISO1600 with no real issues. I bought 20 rolls of 120 format, with the intention that a lot of that will be used on the trip to Mull to make the work that this reflective journal is leading towards.

I also bought 100ft of bulk 35mm to load into cartridges. This works out to be about £2.50 per roll which is much better for me financially that buying individual rolls when I can load it myself with my bulk loaders.

Zenit TTL 35mm SLR Pinhole Conversion – Part 2

These are the first results from the Zenit pinhole conversion. I decided to continue handholding the camera as I was liking the results that I got panning the Ensign camera, even though I am not sure how relevant they are to my work. I do like the fact that when you are panning, if you get it right you can isolate a subject from its background. It reminds me of the work of Alexi Titarenko, although the subject is obviously nowhere near as defined as his – the steps for instance in his St Petersburg work. These images were all shot on a very clear bright day, so the exposures worked out to be about five seconds including additional time to take reciprocity failure into account. This is clearly a short enough time that I can hand hold the camera still enough to get a subject that is recognisable as a person. The last image is even recognisable to people that know him. You dont capture intimate details but enough to make the subject or the scene recognisable.

Zenit TTL 35mm SLR Pinhole Conversion – Part 1

I wanted to see what the result would be of a pinhole camera that had an actual mechanically operated shutter. The simplest way I could think of for trying this was to convert a regular 35mm SLR camera into a pinhole camera. To do this I bought a body cap off of eBay and drilled out a hole in the centre. Over this hole I securely taped one of the Reality So Subtle brass pinhole discs. Coincidently the focal length of this conversion, the distance between the film plane and the pinhole was again 50mm so I could use a 0.3mm pinhole again.

 

The 50mm was measured as accurately as I could but I cant say for sure it was dead on. Even with a vernier calliper it could have been one or two mm out.
I taped over the viewfinder and the old battery chamber to make sure no stray light could get in and the body cap screws in to no light should be able to get past this. I added a shutter release cable that could be locked off to allow for long exposures without holding down the button on the camera and can use it in bulb mode for an exposure as long as required. The frame spacing should be as accurate as it would be when using it conventionally with a lens. The pinhole adaptation should make no difference to this.