Saturday, November 3, 2018

Agfa Jsolette V Bellows Repair

Some months ago, I decided to enrich my collection of medium format cameras by a model that is literally pocketable.
During a stroll in "de bazaar" I found a Agfa Jsolette V, the most primitive one of the Jsolette family. Just about perfect for what I had in mind. For the looks of it, the camera was in mint condition... sold by a serious collector.

The Jsolette V was build between 1950 and 1952. So, consequently, I had to assume that the bellows were probably not a light tight as they should be any longer. And, guess what, when sending photons off some semi-conductor device inside the camera, while being in a dark room, the bellows gave a preview of a Christmas tree all along the folded edges. No surprise, really.

Before I put any film into the camera, I figured it would be a good idea to fix the bellows first. And yes, one can order replacement bellows... while the replacement process is well documented, combined with time of shipment to arrive... this is just not worth the effort.

When browsing for bellows repairs, one finds strange methods using pins and needles combined with dyed glue... not sure about this! Well, this might just work, who am I to judge, but for now long?
Further, one finds comment like "electrical tape is for electricians, not photographers". Hmmm, OK! I remember that in photography, gaffers' tape is commonly used... however, I never came across the comment that "gaffer's tape is for gaffers, not photographers". Something seemed wrong with that electricians tape statement...

And guess what, I grabbed a roll of black electricians tape and put a generous amount along the edges of my camera's bellows. Using about 30% more than the actual length of the edge fives sufficient material to fold the tape into the undulations of the bellows. Too long, and there might be too much tape to squeeze in, too short and the tape might just peel of every time you open the camera.

With the tape applied, I noted that the camera folds open a lot slower, i.e. with a lot less force. What I am trying to say here, you should never just the thing snap open (as many folks show in Jsolette videos). Push the release and let the camera gently open by holding the front mechanism.
And here is the reason why: the atmospheric pressure against the bellows will weaken the most agile parts of the bellows by airflow. Once a hole was created, the airflow when opening or closing the camera will weaken that particular spot, thereby creating a light leak and/or pinhole.

While the bellows of the Jsolette are made of a material that appears to call for electricians tape, that solution might be valid for other cameras using bellows, e.g. large format.


Sunday, October 21, 2018

ISO in Digital Cameras

Doing some film photography here and there, my mind is often with the sunny 16 rule. This rule works for me big time.

However, I noted when using digital cameras, this is somewhat of a different beast. The Fuji X100S seems off by about 1 stop of light (see earlier tutorial), however, the basic principles are working here. With my Fuji X100T, this is a different story.
Today I tried some sunny 16 shots with the X100T @ ISO 200. Fully overcast by bright should have resulted in f/8 with 1s/250 (give or take). That was by far too dark. Auto-exposure brought it to 1s/30, or 3 stops darker. The ISO 200 of my X100T appears to behave like an ISO 25.

For comparison, I got my Leica X2 out at ISO 100. At f/8 with 1s/125 the image was slightly dark, but could be considered well exposed. Auto-exposure resulted in a shutter speed of 1s/80. Mind you, the next real stop shutter speed would have been 1s/60.

What do I learn from this?
  • I will trust the ISO settings in the Leica and snap away with the sunny 16 rule, giving me full control.
  • The Fuji sensor will need some calibration before trustworthy. The native ISO 200 might actually not be ISO 200 at all.
So why bother? It is all about speed and delays. I shoot with manual focus. The only shutter-lag can be created by some auto-exposure in aperture priority.
Operating in full manual control, one needs to be able to trust in some given parameters, e.g. film speed. I expect from digital cameras to actually reflect the correct film speed when I set the ISO sensitivity (aka amplification) of the light sensor.

With my Leica, it seems that I can trust the ISO settings.

Sunday, June 24, 2018

Canon Selphy CP400 under Windows 10

Back in the day, I bought a Canon Selphy CP400. Still have it! This is so long ago, I did not even remember the OS I was using to that time.
Now with my Windows 10 laptop, I wanted to revive the good old sublimation printer for use with Lightroom. Turns out, there are no drivers for Windows 10 available. Still I got the printer working perfectly fine. And this is how I did it.
  1. Download the latest Windows Vista drivers.
  2. Open the download folder and right-click on the downloaded file selecting "properties".
  3. Click the "Compatibility"tab.
  4. Click "Run this program in compatibility mode for:"
  5. Select "Windows Vista"
  6. Press Apply/OK
Double  click to install.
In the course of install you will be asked to connect the printer and power up. The installation should not finish.

The above procedure worked fine for me. Lightroom 5.7.1 on Windows 10 printed flawlessly on the old CP400.

Wednesday, June 6, 2018

Keeping the Old Lightroom Alive

Just as me, you might be disappointed by Adobe's decision to no longer support Lightroom (4/5/6) as standalone programs. As owner of several licenses of various versions of standalone Lightroom, I was looking for alternatives. After having tried several commercial products, I decided to run LR5 as long as I can.
While I am not sure about LR6, 4 and 5 should be OK for the farther future.

However, there is a problem! Over the course of time, electronic cameras (not to call them digital) tend to fail after a few years and require replacement. Someone lately told me that film photography is for the rich. I am not sure about that, for the amount one pays for a new digital camera, a lot of film can be bought! Anyway, that is not my topic for today.
Lightroom RAW support for newer cameras strongly depends on Adobe's updates. With older versions of Lightroom no longer supported, such version won't be able to handle RAW files of "replacement" cameras. Or do they?

It appears that Adobe does not want to totally disappoint former customers, i.e. licensees. For many years, Adobe provides a DNG converter for free. This converter is actually kept updated for the time being.
So, with the additional step of converting directories of RAW files into DNGs, newer cameras will be indirectly supported in older versions of Lightroom.
Fingers crossed that Adobe does not decide to scrap the DNG converter!

The only workable alternative I know of would be RawTherapee. While for certain effects, I actually prefer RawTherapee, this software does not really compare to the general capabilities of Lightroom.

In a way it is funny how dependent a RAW-shooter is on a particular piece of software and therefore from the policies of a particular supplier. And yes, I do know about PHASEONE's Capture One, however, this just adds another dependency from a supplier.

Sunday, October 23, 2016

Huawei P9 monochrome camera - red filter

Having a "monochrome" camera, i.e. a camera that records luminosity only, rather than RGB colors, allows for the good old color filter tricks, without reducing image quality, just as in the days of B&W film. Personally, I would prefer to call the camera filterless, rather than monochrome.

There are a lot good articles what happens when using which filter on B&W film. Here is one of those, please have a look.

Now, what about the loss of quality I was indicating, which does not occur when using a filter-less imaging array?
A regular color image sensor has a filter array printed on it, letting pass red, green or blue light on a respective pixel. In a so called Bayer filter array, the distribution of filters is RGGB. Consequently, only every 4th pixel is sensitive to red light. When using a red filter, for high contrast B&W photography (see article above), the 12 Mpx color camera is turned in a camera having effectively 3Mpx only, since the green and blue pixels will contribute to noise only, potentially creating JPEG artefacts.
In the absence of the RGB filter array, every pixel will be sensitive to all wavelengths, therefore, using a red filter wont affect the resolution or noise levels of the image.

It happens to be the case, that I got some red (LEE Filters 164 Flame Red) gel for spots. Although not perfect, this is pretty good stuff for improvising filters. The filter cuts somewhere in yellow, so, it will result in a little less contrast than a pure red filter.
LEE Filters 164 Flame Red
Those gels are usually just cut to size. So, this is what happened to a small portion of my roll.
A small piece of Scotch tape and the filter gel sits in the P9's case. Mind you, the RGB camera should not be covered!
Small piece of filter gel attached to case

So, what can you expect?
As mentioned above, the filter is a low pass which cuts somewhere in the yellow wavelengths. So, the photographic effect to be expected is in the range between a red and a yellow filter.
To give you an idea, I shot the city hall building, once with the desaturated RGB camera and once with the red gelled filterless camera. As a reference, I added color images from the RGB camera.

Desaturated RGB camera
Red gelled  filterless camera
JPEG converted from RAW (DNG) file
A slightly different angle and one face the shopping mall in Rijswijk. Same test, the effect might be even more obvious here. I metered for the 'IN' sign.

RGB camera

Red gelled filterless camera

JPEG converted from RAW

For the time being, I will keep the Fire Red gel in my phone's case. Should I require all wavelengths, I can easily flip the filter gel away from the camera lens and still keep it inside the case.

Saturday, October 22, 2016

Huawei P9 monochrome camera

Did some comparative photographs today, comparing the desaturated JPEGs from the regular camera and the JPEGs created by the monochrome camera.
The files can be found on this flickr album.
Note that files from the regular camera are indicated by "cof" while files from the monochrome camera are indicated by "mon".

The EXIF data confirms what was to be expected, the monochrome camera is by a bit over 1 f-stop more light sensitive. The monochrome mode could therefore be pretty interesting for low light street-photography. Maybe with image contrast maxed out and image brightness reduced.

Stay tuned for more Huawei P9 imaging experiments, tips and tricks.

Friday, October 21, 2016

Huawei P9 - MONOCHROME mode

Please, HUAWEI, please release a new firmware in which the B&W-camera's data can be written to a DNG-file!

Why oh why would I commence a blog post like this? The hope is that HUAWEI, through a supposedly simple firmware-update, could make this a premium B&W shooter.

Very simple experimentation, i.e. moving a finger in front of the camera modules, reveals, the "MONOCHROME" mode (yes, capitals are used in the menu) indeed uses the camera next to the phone's edge. In a way, that is indeed good news.

In order to judge the quality of the 2 different cameras, I took 2 shots from a photo published by wired.co.uk (credits to Amy Davies) from my laptop's screen.

The first shot is taken with the regular "PRO" mode, desaturated JPEG + RAW(DNG). The second shot was taken with the "MONOCHROME" mode; and yes, I had correct for the parallax of the 2 cameras.

The following images are 100% crops of the same image portion, the pixelation reflects the pixels of my laptop's screen (no camera artefacts!). The DNG-file was opened in RawTherapee.

RAW (DNG) - desaturated JPEG

MONOCHROME JPEG - desaturated JPEG
RAW (DNG) - MONOCHROME JPEG

Clearly, the monochrome camera can pick up the black matrix of my laptop's screen a lot better than the Bayer filter camera, no surprise here.
Further, the dynamic range of the monochrome camera seems a lot better, just like expected.

HUAWEI, it is your hands to turn the P9 a superior camera by allowing to record RAW data from the monochrome sensor. Such a feature would turn that phone into my favourite camera ever easily.