First, yes, I did do a "search" on this topic before posting this. However, the few threads I found were 7-10 years old, and were either from people who take photos of fire trucks or campfires.

I do "fire photography". By that, I mean going to the scenes of brush fires, structure fires, "rescue" calls and other assorted situations where firefighters are involved. The purpose is to obtain good photos for possible publication in local newspapers and fire- and EMS-related publications. I'm primarily interested in photographing aerial firefighting helicopters and fixed-wing aircraft ("air tankers") dropping either water or Phos-Chek retardant. So, now to the "photography" question I have.

I shoot with a Nikon D7100 and D7200, with a Sigma 17-50mm f2.8 on one, and Nikon 70-300mm f4.5-5.6 ED-IF on the other. However, especially when it comes to aircraft, which are often some distance away, sometimes 300mm is not quite enough. Yes, I can crop in and "simulate" the effect of a longer lens that way, but I'm looking at adding a new lens to "reach out" further. I'd like some advice and comments as to which might be the better way to go.

My first choice would be the Nikon 200-500mm f5.6. I would expect most of my use of this lens would be at the 500mm end of its range. The extra 200mm I would get over the lens I already have is significant.

My next option would be either the Sigma or Tamron 150-600mm f5-6.3. A little more on the "wide" end, and another 100mm on the "long" end. I don't care so much about the 150mm and the difference in field of view from 500mm to 600mm is also insignificant and could be simulated by cropping.

I would be interested in which lens is the "best bang for the buck". From what I've read, the Nikon gets points for being the sharpest of the three, the constant aperture across the zoom range and for having the fastest and most accurate AF. However, I've read comments about the Sigma and Tamron claiming that those users are also getting sharp photos and feel that the AF response is excellent.

All three are heavy lenses, heavier than anything I've used before. But, I'm not at the point, yet, where the weight of the lens would be an issue.

I'd rather have a 500mm prime, but even the Nikon 500mm f4 PF is a $3500 lens and not exactly within my budget. So, looking for opinions and recommendations between the three mentioned above.

Thank you.

"What camer and what lens" questions are sometimes difficult to answer because I do not exactly what exactly the photograher specifically wants to capture his or her style, or exact working conditions and situations.

I have not photographed active fires in many years, however, in my 3-year stint working on a daily newspaper, as he rookie on the team at the time, and my getting all the night shifts, I became the official "pyro-tographer" on the crew.

After my first few fire assignments, I quickly learned the actual meaning of "hot as hell" and that available light was always the best method. Flash is oftentimes NOT advisable for the same reason you don't use your bright headlights in a fog- the flash will bounce off the smoke and obscure the entire scene.

As for lenses, a fast zoom is practical. Longer focal lengths are handy because at most structure fires you will not be allowed to jump the fire line, however, you may want some wide range shots as well. Running around a foreground with all the smoke and soot in the air, it is best to work with multiple bodies so you don't need to detach are reattach lenses in that dirty environment.

Fires are self-illuminating so even at night, between the light from the fire and the lighting gear aboard the fire trucks, a moderately fast lens will do the job and with a boosted ISO you can still handhold the camera at reasonable shutter speed. I did learn that using a tripod and making longer exposures- even several seconds, makes the fire look more intense.

As I mentioned, I had not shot fires in many years, that is, until a few years ago, in the middle of the night, a building on a property adjacent to my back yard was set on fire by an arsonist. My wife smelled smoke, awakened me, called the fire department and I shot a few frames as soon as the firefighters arrived. I thought they had it under control but in seconds the gasses emitted by the fire ignited and the entire building was engulfed in flames.

Back in the day, I used 3 bodies- zooms were not all that fast and sharp. On a 35mm camera, equivalent to a full-frame DSLR, I used 24mm, 50mm, and 300mm lenses at fires.

As for waterbomber aircraft in flight, a zoom with a longer focal length range should be practical.

Just asking:

Have you considered trying a 1.4x or 2x teleconverter with your current 70-300?

It would ‘cost’ you one or two f/stops, but you would save dollars and weight. The things weigh about 4 ounces.

With a 2x teleconverter you would be working with a 140-600 mm lens with an effective maximum aperture of f/9 - f/11. Not fast, but your subjects are at great distance, so focus is pretty easy, and ISO can be raised a bit to compensate.
With a 1.4x your max. focal length would be 420 mm at f/8.

Just a quick side note on the use of the term superzoom in the title of this thread. I have also seen references in other threads to lenses with 100-400mm, 200-500mm, and 150-600mm focal ranges as being superzooms. While there is no official standard definition of a superzoom lens, as a general case, the term usually refers to zooms lenses that far exceed the 3x, 4x, or 5x focal range of conventional standard zooms, and have a focal range that goes from wide angle to telephoto. Superzooms generally have significant optical limitations due to their extreme focal range. Wikipedia, among other sources, defines superzooms this way. The 22x Tamron 18-400mm would be an example of a superzoom lens. Based on this definition, the 2.5x range of the Nikkor 200-500mm, for example, would not put that lens into the superzoom category.