Jonathan's blog

Outdated medical technology isn’t normally the kind of thing I’d be interested in, or would write about – but I was given some old glass autoradiographic stripping plates. I didn’t know what they were at the time – I assumed they were normal photographic plates, but I’ve done a little light reading.

Autoradiography

The gist of autoradiography is that you:

• inject a creature with a radioactive chemical
• allow the radioactive blood to be pumped around its body
• kill it
• cut it into thin slices
• stick the slices onto an autoradiographic plate
• leave the radioactive slices stuck on the plate for days or weeks while the image forms – in effect a contact print but the “illumination” is provided by the sample itself, rather than an external light source
• develop the plate in the same way as normal photographic prints

I found the following account in the Journal of Anatomy, 1978:

The investigation was carried out on 10 days old rats. Of the 11 animals used one served as a control and the rest were each injected intraperitoneally with a single dose of tritiated thymidine (2 μCi/100 g of body weight). The rats were killed by decapitation either 2, 12 or 48 hours after injection. The knee specimens were collected, fixed in absolute alcohol for 48 hours and then washed in distilled water. Cryostat sections 7-8 μm thick were cut and mounted on glass slides coated with a thin layer of gelatin. The sections were then stored in an oven at 37 °C.

J. Anat. (1978), 126, 3, pp. 547-554

The article continues to describe how the plates are developed and treated afterwards, which seems fairly typical of any printing done in a darkroom.

This is all good and well, but I have no intention of force-feeding a rodent some Red Bull and then cutting its head off. I’ve hardly been able to find any data about these particular plates – marked as Kodak AR.10. However, both the leaflet with the plates and the previously referenced article mention using a dark red safelight, which implies that the plates are indeed sensitive to visible light as well as X-rays and γ-rays.

Sensitivity to visible light sounds much more useful to me.

Making my own contact prints

As I had a box of 12 I thought it might be fun to try making some prints. And as they were free (saved from the bin!) there’d be nothing lost even if they’d expired or if I ruined them. The plates are 4¾ × 6½ inches, which is a nice size for a novelty glass print (I think).

I started off trying to make a simple contact print, by placing a heart-shaped pad of post-it notes on the plate and exposing under the 60W bathroom light for one minute. I then developed in Ilford ID11 for five minutes, diluted 1:1 with water. I washed the plate in stop bath for one minute and fixed in Ilford Rapid Fixer for two minutes.

The plates certainly hadn’t expired, as the area exposed to the light was black, and the area under the post-it pad was clear. However, the outline of the pad was extremely blurred to the point where it wasn’t possible to tell what it was. I think this was worsened as I had accidentally had the plate upside-down, with the emulsion on the opposite side of the glass to the pad.

I tried again, this time with the emulsion face up. The result was hardly any better. I was disappointed, since if I couldn’t make a simple contact print of a white heart on a black background, the chances of doing anything else successfully were slim at best.

Building an enlarger

My original plan, if the simple contact prints had been successful, was to make some more contact prints of some 6×9 cm 120-format negatives on the plates. They would certainly look unusual. Having failed at any sort of contact print, I wondered if it would be possible to project an image onto the plate.

I don’t have an enlarger or a project, but I do have some very crude cameras that I thought might work in reverse. Using a 1929 Voigtländer Bessa folding camera, a porridge box and a light bulb, I managed to project a 120-format negative onto my wall in a dark room. As you can see, I’ve placed a book on top of the box to keep it still, and propped up the nose of the camera with a smaller box. You can also see the silver shutter release cable. Finally, I draped a black T-shirt over the entire arrangement, allowing just the nose of the camera to protrude, because it was leaking light quite awfully.

My homemade enlarger

The image of the 120 negative was reasonably sharp, but at the camera’s closest focusing distance of four feet, the image stood some 18 inches tall. For too large for a 6″ plate. After a bit of tinkering with some card and I managed to make a holder for a strip of 35mm negatives. When projected, these produced images that were still somewhat larger than the plates, but I thought it would be OK to “crop” them and represent only the central area of the negative on the plate.

Making the image

Given that one minute under a normal bathroom light had produced roughly the right exposure, I reasoned four minutes using a 40W bulb in my enlarger (significantly dimmer) would probably be OK.

After exposure, I processed the plate the same way I had done before. But this time, success! Here’s my finished plate – a picture of my brother riding his bike. (You can see the original image on my photo blog).

My finished plate

Given that the grain is kind of awful, I would guess that the exposure time was too short and the development time was too long. I still have plenty of plates remaining, so I will try more like this after I’ve selected some more of my negatives from the archives. I will probably try exposing for ten minutes and developing for three.

I don’t know about you, but I think this retro-looking plate is incredibly cool. Anyone can do anything with a DSLR and Photoshop, but I think it’s more fun to play with expired X-ray plates and cameras from before my grandparents were born

As my interest in photography progressed, it was only natural I’d one day end up wanting to develop film. I developed my first roll last night by following this guide. It was extremely helpful – but there were a few points it didn’t cover. I made notes while I was developing, and so here’s a modified version of the guide, including my advice.

If you’re interested in seeing what I was able to achieve, some samples are here.

What you’ll need

These are the items in my inventory. I’ve bought “proper” gear where necessary but most of the kitchen-type items came from a supermarket for pennies. I bought the developing tank from eBay, and the same seller was also offering a kit with all the chemicals, listed as Ilford Black & White Film Developer’s pack

• Developer
• Stop bath
• Fixer
• Wetting agent (cheap washing up liquid will do)
• A developing tank
• 3 water bottles – preferably one litre
• 3 plastic jugs – at least one litre
• Funnel
• Kitchen timer (get one with a mechanical knob rather than a digital one)
• Clothes pegs
• A place to hang the negatives sufficiently high that they won’t touch the ground
• A dim light. Colour doesn’t matter- perhaps a torch with half-flat batteries.
• Scissors
• Bottle opener
• Something to stir the chemicals with. I used old picnic cutlery!
• A storage box for all of the above, with a lid.
• Room thermometer

Preparation

If this is your first time developing a film, there are some things you should do first. You should probably do them before every time you develop a film, even if you’ve been doing it for years

1. Familiarise yourself with how to mix each of the chemicals – how much concentrate to how much water, how much you want to end up with, etc.
2. Make a note of how much of each chemical your tank requires you to use.
3. Calculate and make a note of how long each of the three phases should take.
4. Label each of your empty bottles and jugs with a permanent pen so you know which chemical belongs in which jug.

Loading the film

5. Take film, bottle opener, scissors, developing tank and reels into a lightproof room.
6. Organize the materials on a table. You’ll need to know where each item is in the darkness.
7. Turn off the light.
8. Open the film canister at either end with the bottle opener.
9. Take the film out of the canister and cut off the leading tab at the end to create a straight edge.
10. Load the film onto your tank’s spool. The method varies depending upon your tank, but I found my Paterson System 4 tank easy to use.
11. Pull or cut the end of the film off the spool and remove the tape.
12. Drop the loaded reel into the developing tank and secure the lid.
13. Turn the light back on.

Developing the Film

14. Mix chemicals according to directions.
15. Put the right amount of each chemical into the three jugs.
16. Put any leftover chemicals into the plastic bottles for storage.
17. Technically with a good tank you should be safe to have the light on, but it never hurts to be cautious, so at this point I switched the main light off and worked by the light of a dim torch, pointing at the ceiling to softly illuminate the whole room. If you wait a minute or two, your eyes will get accustomed to the low light.
18. Take the top off the developing tank.
19. Pour the pre-measured developer into the top of the tank.
20. Tap the tank against the counter to dislodge bubbles.
21. Agitate the tank by slowly inverting it and turning it back over for the first 15 seconds.
22. Repeat every 30 seconds for the recommended time (usually 5 to 10 minutes).
23. Pour the developer back into the jug.
24. Pour stop bath into the now-empty developing tank.
25. Agitate the stop bath and let stand for 1 minute.
26. Pour out the stop bath and replace with fixer.
27. Agitate the fixer for 15 seconds and then for 15 seconds once every minute for the allotted time.
28. Pour the fixer back into its jug.
29. Remove the lid of the tank and run water into the tank for 15 minutes.
30. Add wetting agent to the water to expedite drying. If you are using washing up liquid, add a tiny drop to the water in the tank and let it sit for a minute.
31. Remove the film from the tank.
32. Gently pull the film off the reel.
33. Attach a clip to the top of the film and hang it up. I hung mine from a clothes horse in the bath.
34. Attach another 2 or 3 clips at the bottom, to prevent the film from curling as it dries.
35. Hang the film in a dry, dust-free area.
36. I don’t know how long it really takes them to dry, because I went to bed at this point. When I woke up, the film was dry and straight.
37. Cut the film into appropriate length chunks for your scanner / envelopes / etc.
38. Store dry negatives in plastic negative sleeves.

Afterwards

39. You can usually re-use the developer several times (although it takes longer each time). Store it in a clearly labelled bottle.
40. You can re-use the fixer. Store it in a clearly labelled bottle.
41. Rinse all of the “dirty” components in warm water and dry them thoroughly before putting them away in a clean place.

Tips & warnings

• The optimal temperature for most developers is 20°C. Processing at a significantly higher or lower temperature will result in soft, easily damaged film or flat negatives. Some developers have a chart on the packaging to give the time correction if your room temperature is different from this.
• Do not remove the top of the developing tank to look at the film until after the fixing stage.
• Use storage bottles that are just the right size for the amount of developer you are mixing. Label a chemical with its name, date and dilution.
• Begin timing each step as you pour chemicals into the developing tank, and start draining chemicals 10 seconds before the time is up.

That is, I wish I wasn’t a cretin when I was a child.

I have an archive of hundreds of photos that I took as a child on various single-use cameras. I’ve scanned in the 6″x4″ prints over the past few weeks and they’ve come out as well as can be expected for grubby, well-handled photos with an inexpensive flatbed scanner.

But last month I bought a 35mm scanner, mainly to scan in new negatives that I will be taking with my 35mm SLR. I’ve also used it to scan in the old negatives. Trouble is, as a cretinous child I had no idea how to look after negatives and I didn’t realise the significance of preserving them. In 1990, who’d have thought that almost two decades later I would want to scan them in?

The negatives are extremely scratched and fingerprinted. The scratches are too wide for infrared scratch removal to be of much assistance. Shame, as it is now impossible for me to have a perfect digital copy of the photos I took all those years ago.

Having said that, the scratches don’t ruin the photos for me. If a stranger were to look at the scans, the first thing they would notice would be the appalling condition. But for me, the photos still conjure up memories of family holidays, weddings and school trips past – regardless of the scratches. In that way, they are still doing their job perfectly.

Today my new 35mm scanner arrived – a Plustek OpticFilm 7200.

The 7200 is the bottom of its range, but perfect for my needs. All of the scanners in the range have the same optical resolution, but some offer features such as iSRD infrared dust and scratch removal, or MultiExposure where the scanner makes 4 images and combines them to reduce noise.

As I’m scanning brand new negatives, I don’t plan to scratch them or let them get dusty. The MultiExposure might have been nice, but it nearly doubled the price of the basic 7200 model, which set me back just £115 from Amazon.

First impressions

Opening, the box I was impressed straight away. Obviously the basic were there: the scanner, power and USB cables but there was also a padded carry case.

The build quality of the scanner definitely puts it in the realm of home users but it’s perfectly fine.

There are two plastic trays: one that can take four slides and one that can take a strip of up to six negatives. I was a little disappointed by the negative tray, as it didn’t have the “dots” to help the film keep aligned and it can be tricky to get the film into it, especially if it’s new film that still has a tendency to curl.

When sliding the trays into the scanner, you can feel it “bump” into notches so it sits in the right place. These notches aren’t as precise as I would like and you can’t always tell if you are exactly in the right place until you’ve done a preview scan.

The software

According to this page, the OpticFilm 7200 is not supported by any SANE backend, and therefore cannot be used with Linux. Shame.

Installation on Windows was easy enough, although the supplied SilverFast software has a distinct “Windows 3.1″ look and feel about it. It works well enough though and after a few minutes of playing I worked out most of the important features.

Image quality

So far I’ve scanned two rolls of film and I’ve been impressed with the results. I’ve been scanning at 3600dpi which gives a resolution of round about 17-18 megapixels. Saved as a TIFF, this takes up about 55MB.

The built-in sharpening feature does a good job – I can’t tell that my scans have been sharpened which is a relief. Some sharpening software overdoes it and you end up with unsightly artefacts.

The colours are good so long as you’ve done all of these:

• Chosen the right film manufacturer
• Chosen the right film type
• Chosen the right ISO film speed
• Done a prescan to allow SilverFast to calibrate itself

In extremely over- or under-exposed photos, the software can do some funny things with the exposure. But I guess the moral of that story is to expose your photos properly…

The photos I’ve scanned so far have either been on old, grainy film or not focussed properly so it’s hard to tell how sharp the scans are. Except that some of my old negatives from a disposable camera had scratches, and these showed up lovely and sharp in the scans!

Conclusion

This scanner is fantastic value for the money.

Sharpness, colours and dynamic range are all very good.

Serious users should consider getting one of the higher scanners with iSRD and MultiExposure which will help with image quality even more. And they still don’t cost ridiculous amounts.

Sample

I took this picture recently with a Canon AE-1 Program 35mm SLR, using a 50mm prime lens and ISO400 Fuji Superia film.

Unfortunately the lab who processed the film also scratched it, which is pretty annoying. But it demonstrates how sharp the scanner is, and highlights the reason for buying a scanner with iSRD.

Flowers