Archive for the 'darkroom' Category
Wednesday, March 8th, 2023
Shooting an ultra fast lens (140mm F1.0) with an ultra large format camera
In short words “this lens is something else”. It’s extremely fast, huge and has a strange focus distance. It was used in Sony CRT Projectors from 1997. I bought it some years ago from a very interesting guy. He had so many more great stuff in his shop and I regret that I did not buy more. It took me some time to find the right opportunity to use that lens. But I think it was worth the waiting. I am glad my friend and former workshop participant Alois Stingl came over with is wonderful ultra large format camera.
Before I could use it, it needed some cleaning, I used a cloth that was soaked with water and just put it on the lens without wiping to avoid more scratches.

I measured the lens at infinity to calculate the F-Stop. I measured 135mm and the front element was 145mm That is about a F0.9 lens. But a document I found on the internet told me its more an F 1.0 lens. Still crazy fast.

When I saw the yellow coating on the front element of the lens, I thought about Mathieu Stern’s video about radioactive lenses. If it really is made of Thorium, it is indeed radioactive, but only for a very small amount. Watch Mathieu’s video to learn more about this Material

Because the lens is very fast it is still dangerous. If it focuses the sun on something, it will start to burn immediately. That’s the reason you should not put the lens near a window and always put a lens cap on it.

I thought it would be interesting to calculate the crop factor of an 40x50cm ultra large format camera. If you use the common formula to calculate crop factors you will see that this plate size has a crop factor of 0.0067 compared to a full frame sensor. With that you also can calculate the comparable depth of field F-Stop. This would also be F 0.0067 compared to F 1.0 on a full frame camera. When I tried to focus on the ground glass, I could barley find something in focus. Thats why you see me focusing for a very long time.


But there is more. a 140mm lens is a tele lens on a full frame camera, but it’s a wide angle lens on an ultra large format camera. This is because of the bigger plate size of the ULF camera. listen to my full explanation in the video.

To “connect” the lens to the camera, I designed and printed a basic flange in Tinkercad. It needed some pool line and tape, but eventually it worked out.



The next issue was the fact that my darkroom was not made for 40x50cm plates. only for 30x40cm ones. After some tests with smaller plates, we only had one cup of developer left. Beside that, everything starts to get unpleasantly expensive if you pour on plates with this size. So my goal was to make it work with only one attempt. I did some dry runs to get comfortable with everything. Not only the dark room work was something I had to prepare for, but also the camera. These old beauties all have some quirks. Besides that, Alois made a beautiful plate holder by himself. These holder needed also some special attention. But as explained in the video, I love these challenges. It makes the result at the end even more sweet.
To calculate the strobe power I needed, I used my wet plate strobe calculator that I created for my Patreon supporters. Since I made it, I use it all the time for myself, because it makes life much easier with the wet plate process. If you are a fan of analog photography and the wet plate process, have a look at our wet plate conversation magazine on Flipboard. Besides many great stories about our favourite process, you’ll wind there also work from other wet plate artists.

But this is not the end, because of some kind of funny coincidence, a former workshop participant sent me a very similar lens over. I am thinking to do a still life plate with that one. What do you guys think?

But there is more, I got also a very tiny lens. I guess I need to build a camera for this one

I hope you enjoyed that journey. It took me a long time to finish everything, but I am again glad that I worked through it.
Wednesday, December 21st, 2022
End Of 2022 Studio Tour
Maybe you missed my exhibition, or you want to come for a portrait or a workshop. Then you have now a chance to walk with me in a brief overview through my studio.
Wednesday, September 7th, 2022
Freilichtmuseum Salzburg Wet Plate Experience (rainy days)
Wet plate in the rain? Sure thats why its called wet plate 🙂 We had a great time in Salzburg and it was a pleasure to be there again. It’s great to do portraiture in these wonderful old houses. You have to visit this museum when you are nearby. It is totally worth it. The best time would be when I shoot portraits there 😉
Wednesday, July 27th, 2022
Darkroom Home Automations
Even I am an analog guy, I am not shy to bring new technologies to my darkroom. With the wet collodion process I always try to avoid touching anything unnecessarily. So I build some home automations to assist me with that. Every analog photographer knows the struggle. You work in your darkroom and in this very moment you don’t want to be disturbed. Just imagine, somebody opening the door and your film/paper/plate is exposed to light. For sure, you just can mount a red light on the entrance door and you are safe. But in my case (and I am pretty sure I am not the only one), I have a main entrance to the darkroom and two other doors. One door leads to my studio and the other door to my pouring room. That means if any of these doors are open, it is safe to enter the darkroom. If I just would have a red light on the main entrance door, it would be hard to understand for my workshop participants or sitters if it is safe to enter. Thats the reason I build a solution for that with Apple Homekit (you for sure can build it also with Google/Alex or anything else). But there is more. We all have running water in our Darkrooms. And I think some people will have a water detector. But what if you have to wash something with running water and are not in your darkroom all the time? I used Homekit for that as well. I show you also a solution for measuring time without touching anything. This may be very specific to the wet collodion process, but maybe it may be helpful for others as well. The last topic is about how I feel more safe with my 3D printer.
I looked also for Google/Alexa devices, but most of them are working with wifi instead of low power bluetooth or thread. So I am not sure if I want to recommend any of these, please let me know which ones work great and I post them here.
Works with Homekit: Eve Energy power switch
International https://amzn.to/3BfCqIH Germany: https://amzn.to/3cEAH5s
Eve Door sensor
International https://amzn.to/3J3MV3S Germany: https://amzn.to/3b4PiXu
Eve Waterguard
Inernational: https://amzn.to/3Pxnn1n Germany: https://amzn.to/3POEJHv
Eve smoke is not available right now, I found only this alternative from Netatmo
https://amzn.to/3Ou6T8Z
Works with Homekit and Google/Alexa
Philips Hue lightstrip
International: https://amzn.to/3J7jnlR Germany https://amzn.to/3cGmZzd
Philips Hue Bridge
International: https://amzn.to/3z6bYP9 Germany: https://amzn.to/3cxRdEl
Philips hue switch
International https://amzn.to/3b1NGxY Germany: https://amzn.to/3Ox1kGX
Apple Watch app https://apps.apple.com/de/app/click-metronome/id705075264
Water resistant JBL BT Speaker (new version
International: https://amzn.to/3Be74Cj Germany: https://amzn.to/3J4DKjA