Saturday, March 25, 2023

Infra Red Pano Test

In this short post I thought I would simply talk about a pano (test) image I just grabbed.

It was shot with my IR converted (720nm) Canon M10.

BTW I get all my conversions, and I have few, from Alan Burch at

The camera was running my Landscape Bracketing Script, which gives me feedback on infinity blur setting and the log-mode CHDK histogram I find is better at ETTRing than the linear Canon one.

I used the LBS script to set a base (handheld) auto-ETTR and adjusted the final exposure using the CHDK histogram. The aperture was set to f/5.6.

I used my 617 CHDK aspect ratio (grid) to help me with my composition setting, which adds a black top and bottom bar.

In post I only used Lightroom, having first applied an IR profile, then adding a linear grad across the entire image and colour inverting this to achieve a blue sky. I then desaturated the foliage a little and toned the image to my liking.

I must say, with its tilting screen, the converted M10 is a great IR travel camera.

As usual I welcome any comments on this post or any of my posts.

XPan Simulator Update

In the last post I introduced my in-camera (G5X and G7X) Xpan simulator, which I wrote to help hone/train my panoramic image capture, especially my composition eye.

The simulator restricts the field of view to the 45mm and 90mm Xpan lenses (35mm is too wide to simulate), but I've added an additional lens preset at 150mm.

It is a simple matter to add other lenses in the script.

In this update (downloaded from the right) I've added the following:

  • The script now handles HDMI out and EVF, ie on the G5X, although CHDK has a quirk and the EVF display will have a gap on the right of the top and bottom black bars.
  • The zoom is now enabled and using the zoom will take the simulator out of the XPan mode and allow you to explore other focal length. The script will, in this case, display the native focal length and the 35mm equivalent.

The following HDMI screen grabs illustrate the various functions/states.

In the above, we see the usual aspect view of the camera (3:2).

After switching on CHDK Alt mode we see the above, telling us CPAN is ready to rune, which we do by pressing the Canon shutter button.

In the above we see the script's start up view, simulating a 45mm XPan field of view, ie based on the XPan's 65x24 negative size.

In the above we see I've switch to transparent mode, by pushing the UP button. I can toggle back and forth between dark and transparent modes by pressing the UPO button.

Pressing the RIGHT button toggles through the XPan lens presets, ie 90mm above.

By using the Canon zoom you will take CPAN out of XPan mode and put it into a mode that gives you feedback on the native focal length you are at and the 35mm equivalent.

Pressing the RIGHT button will take the camera back into XPan mode.

At any time you can grab an image, at the native 3:2 ratio, by pressing the SET button.

Finally, if you don't have access to a CHDK enabled camera, then using a 6x4 grid, sometimes called a G24 grid, will give you a 3:1 pano grid, by using two adjacent rows. Plus, of course, you can use the G24 grid to aid your rule of thirds compositioning.

As usual I welcome any comments on this post or any of my posts.


Sunday, March 19, 2023

Digital in-camera XPan Simulator

In this post I'll continue the pano theme and discuss an in-camera Hasselblad XPan simulator I've created.

The two most iconic pano cameras from the film era are the Hasselblad XPan, allowing a 65x24 mm  negative to be captured on its 135 film, and the Fuji-film G617, with its huge 168x56 mm negative, using 120 film:

If you don't have either of the above cameras and only shoot digital, there are 'alternatives', that allow you to create flat stitched equivalents, at least of the XPan. The one I use, as shown in the last post, being the Fotodiox ROKR TLT, allowing me to use Mamiya 645 lenses on the EOS R, to create a flat stitched RAW of 67x24 mm, after stitching, ie slightly bigger than the XPan.

Of course the downside of shifting is that you can't visualise the full scene, ie only slices of it; which most of the time is OK, eg when surveying exposure for ETTRing.

Composing is a challenge, as is 'just' practising 'seeing' with a 617-eye.

For this reason I decided to write an XPan simulator for my Canon G7X and G5X point and shoot cameras.

The simulator is written in CHDK Lua and allows me to simulate the field of view of the XPan’s 45mm and 90mm lenses. The 30mm lens of the XPan is too wide to simulate on the G7X. In addition, as the ROKR TLT is so close the XPan in aspect ratio, I added a 150mm lens to the simulator, as I have 45mm and 150mm Mamiya 645 lenses.

The script can be downloaded from the right (CPAN = Cropped XPan).

You run the script in the usual way under CHDK.

There are two script menu items. The first allows you to show or hide the CHDK title bar at the bottom. The second menu item allows you to add a shooting delay between 0 and 10s.

The normal G7X screen looks like this:

Here we see a typical manual mode screen, with the Canon stuff switched off, ie just displaying the shutter, aperture and ISO.

Once the CPAN script is run the screen looks like this (note the following illustrations are cut and paste mock ups and not fully representative of the real camera view):

Here we see the script's starting state, ie simulating an XPan 45mm lens.

From here we can do the following:

  • Toggle the CHDK histogram on and off by pressing the left button. You can position the histogram to your liking in the script
  • Switch between dark and transparent modes of display by pressing the top button.  The transparent mode allows you to see the exposure info as you adjust it
  • Toggling between 45, 90, and 150mm lens views is achieved by pressing the right button, with the script zooming appropriately
  • You can capture an image by pressing the SET button
  • Exiting the script is achieved by pressing the down button

 The following illustrates the above:

Although CPAN is simply an in-camera XPAN field of view simulator, I added the capture capability so that you can explore 617-like post processing, as the captured image is always a G7X full image.

As an illustration, I used the script to grab this sunset last night from the top of our house:

Clearly CPAN is not a replacement for the XPAN or the Fotodiox ROKR TLT adapter, but it is a bit of fun, and a useful tool to help you tune your 617-eye.

As usual I welcome any comments on this post or any of my posts.


Saturday, March 11, 2023

Flat Pano Stitching with the EOS R

In previous posts I covered how I capture digital 617-class panoramic images, using Mamiya 645 lenses, in conjunction with my EOS M cameras, using them as digital backs, and either rotational or flat stitching.

In this post I'll discuss how I use my EOS R camera body with a Fotodiox Pro TLT ROKR Tilt/Shift Lens Mount Adapter, attached to my Mamiya 645 lenses:


Placing the full frame EOS R camera in landscape mode, and shifting left and right, to the adapter's extremes, giving a total shift of 31mm, results in a near perfect 617 format after stitching. For example, this image (12450 x 4395) was taken with my 45mm Mamiya lens:

If required it is a simple matter to extend the capture vertically by tilting (I used my Acra-Swiss d4 geared head in this case), to capture six images, ie two rows of three:

This (non-pano) medium format class image, taken with my Mamiya 150mm lens, ended up at 9139 x 5712.

So there you have it, there are multiple ways to capture digital 645 image sets, for stitching in post, to achieve various formats. 

As usual I welcome any comments on this post or any of my posts. 

Monday, March 6, 2023

St Mary the Virgin

In this short post I'm just going to show another field trip image using my EoSM 'Medium Format' Mamiya 617 Pano Stitching Camera.

The location was St Mary the Virgin, in Silchester, a 15 min drive from where we live.

Silchester, has its origins as Calleva, a centre of the Iron Age Atrebates tribe from the late 1st century BC. After the Roman conquest of AD 43 it became the large and important town of Calleva Atrebatum. Unlike most Roman towns, it was never reoccupied or built over after it was abandoned in the 6th or 7th century, so archaeological investigations have given an unusually complete picture of its development.

The earliest walls of St Mary the Virgin are from the beginning of the 12th century. The present building is not more than about 900 years old. About 1100 years before that the Romans came. Some consider that the excavated remains of one building in the old Roman Town may be interpreted as a place for Christian worship dating from about 340AD, though this cannot be certain.

As for the image, I took two rows of three landscape orientated images, having first ETTRed for the brightest part of the scene. The final cropped 617 file is 14199x5011 in size. I went for a simple, record shot, 'look' in the toning ;-)

As usual I welcome any comments or feedback on this post or any of my posts.

Saturday, March 4, 2023

Field testing the 617 Stitching Camera

In the last post I discussed my poor man's Alpa 12 Pano set up, ie at a 50th of the price of the Alpa camera system, albeit not at the same quality ;-)

In this post I'll discuss how I took an image on a recent field trip.

In addition to the equipment discussed before, I also took my iPad with me (I don't have an iPhone) with the Viewfinder Preview App, which helps me survey the scene at the correct aspect, ie 617.

In addition, by taking an image of the scene in the App, I'm able to geo tag the location:

Having decided the composition and the choice of lens, ie 45mm in this case, I'll carry out an exposure survey across the 6 images, ie two rows of three, and set an ETTR exposure for the brightest image, at the aperture of choice, ie f/11 in this case. 

I set a two second delay (I could have used a wireless remote if the camera allowed this) and captured my bracket set.

After ingesting into Lightroom, I first pre processed the images in PureRAW II:

I then let Lightroom create the panorama, and straighten and cropped the image, to a 11546 x 4075 size in this case.

As you can see below my composition was a little out, so I missed the building on the right: a lesson for the future, ie check the left and right image extremes, and take a few steps back!

Finally, after a little bit of toning I ended up with the following pano (note I didn't bother cleaning up the image and cloning out the people ;-)):

As usual I welcome and comments or feedback on yhis post or any of my posts.

Friday, March 3, 2023

Flat Stitched 617 Digital Panos

In the last few posts I've discussed how I approach achieving a 617-style panoramic image by the use of rotation and/or shifting, eg with my 24mm TSE lens. 

In this post, I'll discuss how I achieve full flat stitching, which results in near zero image-to-image distortion and no need to worry about locating the entrance pupil's location.

Before discussing how I do it, let's cut to the chase and say how you should do it: that is go out and buy into this solution:

That is buy an Alpa 12 Pano and, of course, a Phase One IQ4 150 back, which, with a couple of suitable lenses, will set you back some $50,000 or more. 

OK, like me you most probably can't afford $50k, so the question is: can we have some fun at the other end of the affordability scale?

My starting point is a suitable tripod and, as I wish to travel lightish, I'm drawn to the Peak Design Carbon Fibre Travel Tripod, as it comes with a built in levelling capability: so I don't need to buy a additional levelling base. Plus, of course, I’ve already got it ;-)

The next part of the solution is to fit a panning base, which, ideally, should have variable click settings. The one I have chosen is the Andover PAN-60H:

The above, with the tripod, gives me the ability to establish a level panning plane, irrespective of the tripod orientation, so I can rotate my camera in the landscape and know I'm level. To complete things I then add a Sirui L-10 tilt head, giving me full control of composition:

Finally, I now need to consider the camera and the lenses. First, l’ll replace the Alpa 12 Pano with something a little bit more affordable: a Fotodiox Vizelex RhinoCam, in my case for Canon EOS M Cameras and Mamiya 645 Lenses:

As for an alternative to the Phase One IQ4 back, I use two (secondhand) EOS-Ms and have one converted to InfraRed, at a 720nm cut:

Finally, having decided to use Mamiya 645 ecosystem lenses, I acquired three secondhand, near mint, lenses from eBay at 35mm, 45mm and 150m, eg:

The final 'rig' looking like this:

As my intention in this post was only to introduce my really poor man’s version of the Alpa 12 Pano system, I’ll draw this post to a close, but end with a glance into what can be achieved using this fully flat stitching solution - in this case using my IR digital back with the 45mm lens:

After taking two rows of three images, pano stitching them in Lightroom, cropping to a 617 format, I ended up with a digital image file that was 13243x4674, which is equivalent to having a single sensor that was some 70 mm x 25 mm.

As usual I welcome any comments on this post or any of my posts.