Cambo Actar 24mm – Stitching Images
Cambo has built a reputation for designing and manufacturing technical cameras and more recently the Actus system has been proven a favourite choice for many landscape and architectural photographer.
During the recent OnLandscape Conference “A Meeting of Minds” the Actus was on show along with the Actar 24mm and 60mm lenses. The weather was horrendous and now the storms have disappeared we ventured out to test the current Actar lens offerings.
The Actar 24mm is designed to be used with the Actus as it comes complete with a lens plate that locks direct into the front standard. Although photographers are adopting to mirrorless camera systems the majority of users have DSLR systems from Canon and Nikon and require a wide angle lens for the Actus that will focus the extra distance to compensate for the mirror box. This is the reason why there is a large rear element on this lens.
When using a mirrorless camera the focus is racked back a little more away from the lens than a DSLR with mirror box. The lens is inserted into the front standard and locked in place by a lever. Before you shoot any images it is important to find the lens infinity point. Your dealer can show you how to do this, although we will cover this in another blog.
For this test we used the following; Cambo Actus Mini View Camera, Sony A7R, Actar 24mm lens, Standard bellows, CBH-6 ball and socket head and Manfrotto 055 CF tripod.
Using the Sony to meter the exposure at ISO50 was 1/8 sec at F16. The RAW file was captured with generic Sony profile and 2 second self timer to avoid camera shake.
The lens image circle is quite large, 60mm, so can be shifted horizontally 12mm left and 12mm right. For this shot we shifted 10mm left and 10mm right. We chose not to use the rise and fall as the ground and sky wasn’t very appealing.
Once the RAW files were captured we imported the files into Capture One Sony Express and processed them using the Sony Generic profile, 16Bit and saved as a TIFF file to preserve the data. Capture One pre-set sharpening was used, as shown below, there was no need to increase this. The hand rail and window detail is sharp.
The auto merge in Photoshop CC2015 is extremely good. We had a slight edge to the left and bottom of the file when merging, probably due to the positioning of my tripod on the cobbled paving!
Select Content Aware when using auto merge and this will calculate the edge fill. Photoshop does a great job of this and as you can see from the image you can’t tell this adjustment has been made. The ant trail is shown on the image, select the Content aware tool and click on the ant trail to complete the fill.
The Photoshop layered file to be stitched is 938.6MB layered file, 322MB (flattened.) The TIFF file is 1.59GB. The pixel dimension of the capture is 11456 x 4912 at 300dpi / Print output 38.18” x 16.37” 300dpi.
The images we use for the blog are 1080 wide at 72dpi, reduced to manage on the blog. The cropped imaged was taken from the middle of the panorama at 100% zoom. The file is 15.7MB, 2528 x 1087 at 300 dpi with a print output of 8.42” x 3.6” at 300dpi.
The day started and ended with mist. The image was captured around 14:30 and there was still a small amount of mist across the distant Elizabethan building.
Our next blog shows results from the Actar 60mm. Sign up and don’t miss a post. For further information about Cambo products contact your nearest dealer– Dealer Search.