I originally received this lens back late 2014 when the Sony A-mount was issued. It is big and heavy (1.951g/4.3lbs) and very long when extended in use. Closed without the hood attached it's 10.5 inches(270mm) and fully extended with the hood on it's 17 inches(430mm) then you add on the camera and it comes to around 20 inches(501mm). I used it attached to a Sony SLT-A77II/24.3mp digital camera which itself has a bit of weight to it (25.61oz/1.6lbs) and does help balanced out the lens a little bit. I hand hold the camera and lens combination and have the tripod mount resting in the palm of my left hand and used my thumb and index finger to adjust the zoom ring. Unfortunately you can not rotate the zoom ring from 150mm to 600mm in one go. Well you can but you end up doing contortions and standing awkwardly with your elbow pointing skywards. With panning I quickly found that with the lens at 600mm I could comfortably rotate the zoom back to around 300mm in one move when the aircraft got closer and then zoom out to 600mm again. Auto Focus, driven by an Ultrasonic Silent Drive (USD) motor, is very fast and quiet on the lens but one thing I do miss is a focus lock button on the lens barrel. There is a lock on the lens to stop it creeping if you point it downwards though. The lens is designed for both full-frame and APS-C image sensors with a 1.5x crop of the Sony APS-C sensor the 35mm equivalent focal length equates to around 225-900mm except it was reported at the time of release that the max focal length of the actual lens isn't 600mm but in fact 582mm.
Duxford Air Show ~ 8th & 14th September 2014
I use the camera in manual mode as much as possible, setting the shutter speed around the 1/400th second mark to give propellers a bit of blur and for hand holding is probably a bit on the low side with the lens at 600mm. Although the A77II has in-camera stabilisation, with the lens extended at 600mm and a shutter speed of around 1/300th second, the vibrations of the shutter blades opening and closing can contribute to soft/blurred images. Aperture varied from about f/7.1 to f/11 depending on the light available and the ISO left on AUTO, up to a max of 1600. Metering Mode on Centre which measures the average brightness of the entire screen while giving priority to the central area of the screen.
The A77II has what Sony calls 4D Focusing. According to Sony literature - ‘Conventional autofocus (AF) deals with space alone. 4D FOCUS goes one step further with an innovative image sensor that picks up both space and time to capture moving subjects with new clarity, allowing you to take crisper photos than ever.’
The 4D bit of the auto focus tracking is that the AF software stays locked on the subject matter and can even predict where it will be in the next frame before you take it. To take advantage of this I used the following settings -
Focus Mode - AF-C
Focus Area - Wide
AF Tracking Duration - 5(High) (Found in Menu ‘Camera>4)
AF Drive Speed - Fast (Found in Menu ‘Camera>4)
Priority Setup - Balanced Emphasis (Found in Menu ‘Cog>4)
To aid the focusing process I use Back Button Auto Focusing (BBAF). When the shutter button is pressed half way down, then auto focus is activated and locks on until the shutter button is pressed fully down to take the picture. BBAF separates the AF activation from the shutter release and BBAF activates the auto focus continuously. I have the AEL button on the back of the A77II set for BBAF, easily changed in the MENU, as it’s within easy reach of my right thumb.
I use the camera in manual mode as much as possible, setting the shutter speed around the 1/400 second mark to give propellors a bit of blur and for hand holding is probably a bit on the low side with the lens at 600mm. Aperture varied from about f7.1 to f11 depending on the light available and the ISO left on AUTO and Metering Mode on Centre Weighted Average. I've found in the past that if you use just shutter or aperture priority and let the camera work out the other settings, it can tend to get them wrong and hence under/over exposed images.
The Shuttleworth Air Show was held in bright sunshine and I had no problem's with the image quality which is bright and vibrant and coming out very sharp, even at 600mm at slow shutter speeds. A week later at Duxford and it was cloudy and overcast. At times I was using the camera aperture at f6.3 and as with my Tamron 200-500mm lens, the 150-600mm did struggle a bit with grey aeroplanes against grey clouds. As with most lens with a maximum aperature of f5, they work better in bright light like sunshine. Several times it lost focus lock, something I didn't get with the Sony 70-400mm G SSM which starts at f4. When that started to happen, usually at the 600mm end, then I just pulled back on the zoom a bit and focus was re-established with the super fast 79-point phase-detection AF system in the Sony A77II.
Although the specifications for the lens say that there are three 'Low Dispersion' elements to correct chromatic aberrations, or color fringing around high contrast edges, this still occasionally occured in some of my photos not that I noticed it at Shuttleworth but more at Duxford where the sun is generally in front of the aircraft and I had the aperature open wide. I did manage to control it by adjusting camera settings. Vignetting, or the darkening of the corners of the image when compared to the center, did occur from time to time. Nothing that can not be corrected in image processing software and Tamron have thoughtfully provided a lik and product key, included with the lens paperwork, to download a copy of SILKYPIX Developer Studio 4.0 which can be used for the vignetting/chromatic aberrations corrections amongst other things.