Thoughts on compromise
Camera equipment is a set of tools, a means to an end. Taking a photograph in the field can be an imperfect business. In selecting a set of cameras and lenses the question that should be asked first is, "what is the goal in terms of subject matter and process"? The next question should be, "what are the best tools to achieve the goal.
The question about a photographic goal relates primarily to subject matter and how and when you photograph. It's obvious that a wildlife photographer would have a different set of equipment compared to say a professional portrait photographer working in a studio. For an amateur travel photographer it would be different again.
The temptation to aspire to the newest, most highly rated gear is strong. This amateur photographer faces compromise because there is a difference between "the best" equipment and that which is most suited to achieving the photographic goal.
Over time I have found photographers who's advice I trust. They make excellent photographs, don't quote test numbers and talk in technical jargon. They are generous in relaying their real world experiences. When a final decision is to be made on equipment purchase I pay attention to them.
What is the photographic objective?
These three points detail my current requirements together with explanations.
Principal photographic interest: architecture and landscape
I find that architecture and landscape are similar in equipment requirements and shooting style so that's an immediate advantage. Both require wide to very wide lenses, a tripod and a leisurely approach to image capture. But both can benefit from longer focal lengths to get in close to architectural details or to 'compress' landscapes. The assortment of lenses I have currently covers the range 15-210mm (full frame equivalent). I find that meets my needs and is achieved with three lenses of three different brands and an adaptor. That is not convenient, nor sensible.
Process: I travel and like to travel light
Airlines have a 7kg limit for carry on luggage so that makes a paired down kit a necessity. In the past my bag usually had one or two camera bodies, several lenses and a laptop computer as well as personal items. Often when out and about during the day I will only cary a camera with a 24-70mm lens. That's all. Swapping lenses is a hassle and it results in the accumulation of dust on the sensor. My habit of using one camera/lens combination is a compromise that means I miss opportunities that require a wider or longer reach.
Accessories: A good tripod is a necessity
Some years ago I purchased a carbon fibre tripod. It is bulky and, despite the carbon fibre, is relatively heavy. Small, light weight but sturdy tripods have a place. They put the camera close to the ground which can give a different perspective on a scene. They are compact and light weight and, without much compromise, make a desirable travel tripod.
What are the best tools?
When I decided to buy a digital camera I chose the Konica-Minolta Dynax 7D because the body bristled with knobs, buttons and levers. I liked this because it meant I wouldn't have to dip into menus just to take a photo. The camera had Minolta DNA and Minolta had a reputation for building very ergonomic camera bodies. Then twelve years ago on Sony acquired Minolta. When I had to upgrade the camera I had the option of staying with Sony which was a big unknown so far as the evolution of the product would be or going to one of the majors. My old film camera is a Nikkormat FTN. With a 35-105 lens it weighs 1.38 kg. I think it was carved out of a solid block of brass! I tend not to follow the crowd so I took the risk and stayed with Sony to see what would happen. I don't regret the decision. The only problem is their technology improves so rapidly that it is hard to keep up. Gear envy is a problem.
Since the Konica-Minolta days my camera equipment has grown into an uncoordinated mess. Purchases have been made without a plan and so I have two functioning camera bodies and an assortment of ten lenses about half of which are rarely used. Several are damaged and don't work.
I realised I had to think carefully about the most important aspects of my photography then rationalise my equipment to a set that would perform optimally. Having made those decisions I am in a position to rationally select cameras, lenses and accessories that will fulfil the requirements. So here is the result of that process.
My current cameras
Sony A6000 APS-C and Sony A7 full frame
My current lenses
Sony E f3.6-5.6 16-50mm (24-75mm eq.) kit lens
Sony-Zeiss FE f4 24-70mm
Voigtlander FE f4.6 15mm prime
Sony A mount f4.5-5.6 11-18mm (16.5-27mm eq.)
Sony A mount f3.5-4.5 16-80mm (24-120mm eq.)
Minolta A mount f1.7 50mm prime (75mm eq.)
Minolta A mount f2.8 100mm macro (150mm eq.)
Minolta A mount f4 70-210mm (105-315mm eq.)
Several years ago Sony were criticised for not having a good range of lenses. That is no longer the case. Some of the new FE (full frame E-mount) prime lenses are the sharpest available. The range is still deficient in some specialty lenses but that's not of concern to the majority of amateur photographers and it's likely that Sony or a third party will remedy that. This means my A-mount lenses and the adapter can be sold and replaced with appropriate Sony, Zeiss, Tamron or other E-mount lenses.
There's no argument, a full frame sensor performs better than a crop sensor. My experience is that I can't tell by looking at a print if it was taken with the A6000 crop sensor, or the A7 full frame. The big difference on paper between these two and their more recent versions, the A6500 and the A7III, is in ISO performance. I like to take twilight and night photos of buildings but the camera is almost always on a tripod with ISO set at 100 so the poorer ISO performance of the crop sensor is not a problem most of the time.
Dynamic range is another factor that favours full frame. In the case of the A6500 at 13.7 Ev and the A7III at 14.7 Ev the difference is one stop, a small compromise. Dark interiors are a different matter. Usually tripods are not allowed inside buildings so shooting with high ISO settings is necessary. Fast lenses and in-body image stabilisation are a solution to this problem. The A6500 has in body stabilisation that works in conjunction with stabilised Sony lenses.
Crop sensor lenses have the advantage of being smaller and lighter than their full frame equivalents which fulfils my requirement for light weight, compact gear.
The choice between primes and zooms involves another compromise. No zoom will even match the image quality of a prime but no prime can match the convenience of a zoom. That said, the best zoom lenses are remarkably good.
Two Sony A6k cameras, each being fitted with a zoom lens that together covers the 15-200mm range would be my perfect kit. Being compact and lightweight, I could carry both and be prepared for any architectural shot, or for that matter any landscape or street opportunity. When travelling, a small tripod would usually be adequate for night shooting.
I already have the A6000 and Sony recently released the A6500 which, according to DxO is top of class with many improvements over the A6000, the relevant one being in body image stabilisation. Crop sensor cameras have the advantage of a greater depth of field, which suits architecture and landscape work but is not so good for portraiture.
For some time Sony have had an E f4 10-18mm OSS lens (OSS = stabilised) which performs well provided it is stopped down to f8 at the wide end. For depth of field reasons f8 is my preferred setting on the crop sensors. Also, f8 is near the 'sweet spot' for the lens. Sony recently released an E-mount f3.5-5.6 18-135mm OSS. Together these two zooms will give me a complete zoom range from 15mm to about 200mm.
The reviews of the lenses have been good but there are the usual unavoidable problems of softness in the corners of zoom lenses when wide open but shooting in the middle of the f-stop range avoids, or minimises, most of those problems. Distortion and vignetting are easily fixed in software so I feel confident these lenses will do the job.
If the best image quality is required for large, quality prints primes are desirable. Sony and Zeiss make excellent 50mm lenses which are suitable for portraiture at 75mm FF eq. I will keep the Voigtlander which will give me a very useful FF eq. of 22.5mm. With regard to cameras and lenses that should keep me happy for awhile.
I will keep the tripod but look to invest in a a small, compact, sturdy tripod to supplement it.
The only remaining problem will be to continue the never ending quest for the perfect camera bag to take this kit.