TonyM
Well-Known Member
- Joined
- Jul 30, 2013
- Messages
- 5,417
- Reaction score
- 5,095
- Country
- United Kingdom
- Dash Cam
- A139, M1S
After experimenting with this f1.6 6-22mm varifocal lens on a Mobius 1, I decided to give it a go on a GitUp F1.
This particular lens is from Treeye via AliExpress who have an excellent track record of customer service. They have supplied varifocal, wide angle and telephoto lenses to a number of DCT members who have experimented with third-party lenses, primarily on Mobius cameras but also the F1 and some others.
The 6-22mm lens is designed for a maximum 1/2.5" sensor, which matches the Sony IMX317 inside the GitUp F1. The back focal length is specified as 6.2mm, although there is some tolerance in where the lens is set relative to the camera body. To position the lens at about 6mm from the sensor I used an M12 extension ring between the lens holder and the lens.
I set the lens to its widest zoom setting at the 6mm end of the range, which should mean the lens is operating at its widest f1.6 aperture - the aperture reduces as the lens is zoomed towards its telephoto end. CORRECTION: The lens was not set at its widest zoom, in fact it was much closer to the telephoto end of the zoom range.
On a static scene there is good sharpness and depth of field, although the detail drops off a bit to the sides of the frame. I should point out that getting the focus point just right for optimal depth of field can be tricky with these high magnification varifocal lenses, so my initial results may not represent the best possible performance from this camera & lens combination.
The F1 is set to 4K 30fps with superfine quality (72Mbps) and medium sharpening. Click the image then double-click to see it at full resolution.
In this mostly static street scene there is good detail from front to back, although the potted plants to the left of centre have lost some definition. The red car on the right is approaching at about 10mph.
This comparative image from a Mobius 1 (1080p 30fps) with the same 5MP 6-22mm varifocal lens has considerably less texture detail beyond the car immediately in front. The Mobius 1 image is zoomed in slightly more than on the F1, partially due to the crop factor on the smaller sensor in the Mobius 1. The focus point on the M1 is also set a bit closer, which affects the depth of field and accounts for some of the loss of detail in the background.
Moving on to another street scene at low speed there is generally good detail in the F1 image, although there is some loss of detail again on the left side:
The Mobius 1 once again has less detail throughout the image.
Driving on the open road, the F1 starts to show much more motion blur despite the f1.6 aperture:
By comparison the M1 delivers a more useful image with less motion blur:
The same higher degree of motion blur can be seen in this example from the F1:
Whereas the Mobius 1 maintains its performance advantage:
Both the F1 and M1 were mounted side-by-side on a metal plate attached to the same sturdy screen mount, so they should experience a similar degree of vibration or movement within the car.
In conclusion, the 5MP f1.6 6-22mm lens performs fairly well on the 8MP GitUp F1 in static and slow-moving scenes. This might make it useful in certain situations. However it shows much more motion blur at medium and high speeds than is acceptable for use as a dashcam.
This particular lens is from Treeye via AliExpress who have an excellent track record of customer service. They have supplied varifocal, wide angle and telephoto lenses to a number of DCT members who have experimented with third-party lenses, primarily on Mobius cameras but also the F1 and some others.
The 6-22mm lens is designed for a maximum 1/2.5" sensor, which matches the Sony IMX317 inside the GitUp F1. The back focal length is specified as 6.2mm, although there is some tolerance in where the lens is set relative to the camera body. To position the lens at about 6mm from the sensor I used an M12 extension ring between the lens holder and the lens.
On a static scene there is good sharpness and depth of field, although the detail drops off a bit to the sides of the frame. I should point out that getting the focus point just right for optimal depth of field can be tricky with these high magnification varifocal lenses, so my initial results may not represent the best possible performance from this camera & lens combination.
The F1 is set to 4K 30fps with superfine quality (72Mbps) and medium sharpening. Click the image then double-click to see it at full resolution.
In this mostly static street scene there is good detail from front to back, although the potted plants to the left of centre have lost some definition. The red car on the right is approaching at about 10mph.
This comparative image from a Mobius 1 (1080p 30fps) with the same 5MP 6-22mm varifocal lens has considerably less texture detail beyond the car immediately in front. The Mobius 1 image is zoomed in slightly more than on the F1, partially due to the crop factor on the smaller sensor in the Mobius 1. The focus point on the M1 is also set a bit closer, which affects the depth of field and accounts for some of the loss of detail in the background.
Moving on to another street scene at low speed there is generally good detail in the F1 image, although there is some loss of detail again on the left side:
The Mobius 1 once again has less detail throughout the image.
Driving on the open road, the F1 starts to show much more motion blur despite the f1.6 aperture:
By comparison the M1 delivers a more useful image with less motion blur:
The same higher degree of motion blur can be seen in this example from the F1:
Whereas the Mobius 1 maintains its performance advantage:
Both the F1 and M1 were mounted side-by-side on a metal plate attached to the same sturdy screen mount, so they should experience a similar degree of vibration or movement within the car.
In conclusion, the 5MP f1.6 6-22mm lens performs fairly well on the 8MP GitUp F1 in static and slow-moving scenes. This might make it useful in certain situations. However it shows much more motion blur at medium and high speeds than is acceptable for use as a dashcam.
Last edited: