Nature and travel are pretty wide remits. Nature could be anything from a greenfly to an elephant, as far as size goes. One would require a 'macro' lens set up to get frame filling pictures, the other you could probably snap from a couple of miles away with a wide-angle.. whilst you could be travelling anywhere from Antarctic to Africa, on your tod with a back-pack and change of undies, or fully supported in a limo with a couple of bus loads of porters and a butler!!!!!
In my teens I was a transatlantic child, and at Easter I could be in the wilds of Wales with the school, and in the summer on the gt prairies of the west, and or anything in between. My companion in travel for that period and 'till today, is a very compact little 35mm 'Instamatic' film camera, an Olympus XA2, that has a fixed 35mm lens, and if you want to 'zoom' you have to get closet to your subject, or hold a magnifying glass to the print!
That camera equates with your camera-phone to a large extent. It's in your pocket, so when you see something you can take a photo. Which is to lead into the question; Do you want to take pictures, or learn photography? Think hard about that. An SLR, digital or otherwise, is 'an enthusiasts' camera for the most part, and it begs the 'feature' you don't get with a camera-phone of compact, of interchangeable lenses.
A camera-phone has a lens. Or should have. And it will normally be of a fixed focal length or angle of view. If you have a 'zoom' compact, that will normally have a travelling lens that can travel from a wide angle to a telephoto angle of view. Your camera phone or a cheap digital compact, might have what is called a 'digital zoom' which mimics the effect of a travelling lens, cropping more off the top, bottom and edges of the picture the fixed lens sees, to show you something 'like' you would have got with a longer or more telephoto lens... but it's not really... its just a smaller section of your picture cut out and enlarged more. This is oft the main reason for going to an enthusiast SLR. The ability to use alternative lenses of your choosing, rather than a fixed lens, chosen by the makers.
WARNING: and its a slippy slope from there! Into Gadget-Acquisition-Syndrome, buying cameras that can take alternate lenses and other accessories, then trying to get as many as you can.. and find a use for them all!!!!
Back to top.
Your camera-phone takes pictures. What do you want a fancier bit of electrickey to do, that it doesn't?
For portability, a compact may have merit, but, your camera-phone already has that. On your travels will you take it? Will it be of any use, other than as a camera?
A 'Bridge' camera, is sort of a compact point and press with extended capability, usually through a telephoto lens with an enormous amount of optical travel, that's often a bit of a con. I don't much like them, and there's one sat in arm's reach in-front of me. It boasts I think a 300x 'optical' zoom range which looks fantastic on the box. Its effectively the equivalent zoom range as my DSLR, from approx 18mm to 450mm. Imp-ress-ive. to the lay-man. It is NOT as the sales-man would have you believe, "All the camera you could every want, in one box!"... really, it isn't. The camera body itself is very small and very light, which the salesman vaunted as an advantage for my little mitted missus.... own-lee, that small and that light, IF you actually use the full extent of the 'zoom', things tend to get rather blurry, IF you can actually keep them in the frame, as camera shake starts to bite, and the much vaunted 'Vibration Reduction' or 'Image Stabilisation' (Depending who's box you are looking at!) starts to struggle. Not helped by a small niggle caused by small aperture settings that get smaller the more lens zoom you use, which beg ever faster shutter speeds, but, the longer lens 'zoom' begs the opposite and you probably don't get the faster shutters you need or want... so get blurry photos... which is why that bridge is on the shelf next to me.. O/H bought it on the salesman's say so, to snap her tear away tot grand-daughter, an infant streaker, as far as photo's were concerned, grumbled that I didn't have this problem.. so started stealing MY camera, convinced it was the kit in her mit, that was the problem, not the know-how in her head... like I say, do you want to take photo's or learn this feaux-togg-raffy lark? Better photographers take better photo's NOT better cameras.
Moving up then from Bridge Cameras, we get to Entry-Level DSLR's, that have these interchangeable lenses. Worth a mention, are Micro-Four-Thirds 'System Cameras, that are, frankly a peculiarity, and I do NOT recommend for a newbie.
Lets talk sensor size for a moment. In a camera you have a lens that captures the light from a scene, and chucks it at a sensor (or film) where its captured and turned into a 'photograph'. A 'Full-Frame' digital camera has a sensor the same size as the 'frame; of a 35mm film camera, 24x36mm. And that is probably the most common format, so the one everything tends to get compared to.
Most entry-Level and consumer Digital Single Lens Reflex cameras, us the APS-C sized sensor which is half the size of a 35mm Full-Frame, at 26x24mm, or near enough. The legacy that created this format, was that at the tag end of the film-only era, they tried to make a small-format film, called the 'Advanced-Photo-System', which to all extents and supposes was something of a flop. BUT with early digital sensors difficult and expensive to make, and tooling to make APS format cameras paid for but lying idle, these were what camera makers turned to to make 'Digital SLRs'. The -C standing for 'Crop', and often referred to as 'Crop-Sensor' cameras, because the smaller sensor behind the lens 'crops' more off the top, bottom and sides of the image the lens chucks on it. These then were the first Digital, all electric, cameras with interchangeable lenses for the enthusiast
Micro-Four-Thirds, then, was the brain child of Olympus. Who through the film-only era had steadfastly and erratically paddled their own canoe, vaunting at various times their own 'half frame' (16x24, the same as APS) Cameras, that took 35mm film, but only used half the length to put a frame on it. They also championed the proto-bridge all in one camera, back in the late 1980's, a large compact with a built in, non interchangeable, large range zoom lens... but still.....
MFT, is 1/2 the size of APS-C, approx 18x13mm square. Its bigger than the 'micro-sensors' usually used in compact and bridge cameras, but not quite as big, or bulky as APS-C let alone Full-Frame digital cameras. And to give an 'equivalence' to interchangeable lens SLR's... which begs explanation that SLR stands for 'Single Lens Reflex', and more legacy, in that the 'Reflex' bit is the periscope mechanism that lets the user look through the same lens as takes the photo, which is what makes these cameras so bulky, but not as bulky as lugging around two lenses of every length you want to use, as you might have on a 'Twin Lens Reflex' camera, that, preceded them, and normally took MUCH larger 60mm wide , 120 format roll film... MFT exploited the fact that the lens put the image on a digital sensor, and you could look at that on an electric screen, much more easily than through the lens; so that's what they did, and made a tiny little screen to look at, and stuck it in a peep-hole like an SLR or range finder had, and called it an Electronic View Finder, or EVF. Which MAY explain a bit of jargon for you.... or might just confuddle you even more.... get used to it... that's how it in in this feaux-tog-raffy lark!
ANYWAY, great as the MFT 'system' may be; it has not gained the widespread market adoption that the APS-C format has. The smaller sensor format did make the cameras cheaper to make, and it did make them more compact, and yes, the major camera maker's; Nikon and Canon DO seem to be moving towards similar 'Mirror-less' (NO complicated pentaprism or 'periscope mechanism) cameras like MFT, but with bigger sensors... which may support a lot of MFT pundits arguments for the system... B-U-T.. its still a bit of an oddity on the market-place.
The incumbents are Nikon and Canon and the APS-C format. That is what most folk use, that is what there is most know-how and most accessories, including these alternate interchangeable lenses are available for, and for a newbie, what you will find is most easy to get, and get on with, 'cos that's what there's most of about. MFT cameras, especially 2nd hand, can appear to be absolute bargains, but bargains that loose their shine as soon as you want to buy something, like a lens, that you have got an interchangeable lens camera to be able to exploit, and find that they aren't as common, or as cheap as the cameras they fit. You have been warned!!!
SO.. APS-C, is the defacto-standard sensor format, and the incumbents in that market are Nikon and Canon. Each brands having their own quirks and foibles; personally I find my Nikon more intuitive to use, with a wheel to set the exposure modes and another thumb wheel to set the shutter speed and aperture, MUCH like my old film cameras. Canon I found to be much more like the mobile phone I wanted to launch off the nearest bridge, all the modes and settings to be found in menus accessed by much tiny, fiddly, button prodding. But that IS mostly personal preference and what you are more familiar and comfy with, but why also you HAVE to get in a real world shop and get hands on, to discover what you prefer.
To conclude comment on sensor size; the larger the sensor, and consequently usually the camera, so the more expensive the camera is to make, and the more up-market, and often 'professional' it's marketed as. There are benefits to a bigger sensor, but the leap from a camera-phone 'micro-sensor' to a small scale, MFT or APS-C sized sensor, will pretty much mine those out for most folk, and the differences from 18x13 MFT to 14x36 'Fulll-Frame' are peculiarly small, and APS-C is a fairly good compromise for most.
You should also NOT compound or confuse the sensor size with the sensor's 'Pixel Resolution'. More Mega-Pixels does not necessarily mean any 'better' photo's, and a bigger sensor does not mean more mega-pixels. The more Mega-Pixels a sensor can produce, so the smaller the 'dots' that make the picture you look at... sort of.
Worth noting that whatever 'resolution' an electric picture maker, makes in its 'data-file' of paint-by-numbers image data... what you LOOK at is a screen. Whether that's on the back of the camera, a mobile phone, a computer-monitor or a TV-Set.... what matters is how many dots or pixels that can show you. For illustration, my EPM produces 24Mega-Pixie image files. The screen on the back, I think, only has about 1 Mega-Pixel of screen resolution, so it's chucking away a big chunk of resolution there. Which incidentally is one of the arguments for proper SLR's that have a purely optical view-finder, and against 'Mirror-less' that are always resolving what you look at from a paint-by-numbers data-file. But, when you come to look at your picture on a screen, the limiting factor is how many pixels that can show you, and typically, for most web purposes, that's around 1 Maga-Pixie, and whatever you 'make' at source on the sensor, will be diddled to fit on the screen you look at. For note, my first Digital camera was a mere 1.3 Mega-Pixel compact, almost 20 years ago, and for Web-Display, I have had to 'shrink' even the meagre pixel resolution of photo's that made, down to around 1 Mega-Pix, to fit on a computer screen. And there art many layers of diddlement; from looking at your pictures on a computer, after you have taken them, through managing them in proprietary 'comes with the camera' computer software , or 3rd party editing software like Photo-Shop, and THEN if you upload them to a web-host to display on something like Facebook or Flikr, where the 'host' software has diddlement in it usually to 'compress' the file-size, which also shouldn't be compounded or confused with the image size or pixel count, but employed to shrink the number of Mega-Bytes of memory space the picture takes up on disk or server.
Which is ALL to say, that you 'probably' don't need be to bothered about the Mega-Pixel resolution that any particular camera may offer... that's what it may make; but what you will look at, even on the camera will be hundreds of times less. As said, my first Digi-Compact, nearly 2 decades ago only offered 1.3 MPix, and I still had and have to shrink that 'resolution' for most practical purposes. My current 24MPix DSLR ofers that much more... so I am just throwing away more, when I come to look at them. Main reason for that 24Mp camera, was that the old digi-pact had packed up, and I needed a new Electric-Picture-Maker, a-n-d, I have a penchant for 'Fish' as in fishe eye lenses, that make a round image in the middle of the frame, and so only use about 2/3 of the pixels the sensor might make anyway.. and people get 'funny' about fish-eye pictures, asking things like "Where are the corners?", so by the time you have diddles them, and chopped a square out of the circle, that 24Maga-Pixel image file, can be down to around 10Mage-Pixels actually used... so the high pixie count gives me that much 'extra' to play with and me the choice what to throw away, not the arbitrary programming of a host site! It gives you more 'wiggle woom' essentially. Practically, anything made in the last 20 years probably has more than enough Maga-Pixies, and almost certainly anything made in the last decade should.
That presses on a lot of 'techno-features' on modern cameras that like the big impressive 'equivalent' zoom range boasted on the lens of a bridge camera, the Mega-Pixie count boasted on a lot of camera-phones and consumer compacts, a LOT of it is mere marketing. You really don't need to be to fussed by it. End of the day, I have a 60 year old 120 roll-film 'Folder', bequeathed to me by a relative, that takes 6x9cm negatives, with a Zeiss lens, and a 'resolution' you just dont get with 35mm, let alone widgetal... a-n-d, folded, it is compact enough to slip in the back pocket of my jeans; its not a bulky camera.. B-U-T... it does lack most of the user easements we have come to expect over the last half century... like an inbuilt light meter, and maybe a coupled electronic aperture and shutter to make it a bit more point and press friendly; you do have to do it all manually, starting with assessing how bright your scene is, by eye or with a hand held meter, which can take a bit of skill and practice... b-u-t again, I have taken photo's with my EPM, metering the day-light by eye using the f16-Sunny rule of thumb; focused the lens by scale rather than viewfinder, and got some cracking results... of tear away tot... so not necessarily so slowly, just less conveniently, with just a little 'know-how'...
WHICH brings us back around.... do you want to learn photography, or just make pictures?
If you just want to take photo's, then like I said whats wrong with the camera phone you got?
IF alternatively, you want to learn photography, then a more versatile interchangeable lens 'system' camera is more appropriate and has the scope to start messing and exploring the potential.. heed warning over GAS.. but, the 'sensible' choice is to skip over bridge cameras and MFT or Mirrorless, to avoid the pitfalls they bring, and do the normal thing and start with an entry level DSLR from Nikon or Canon according to your preference and price range.
And to annoy Phil, YES, entry level cameras are designed to give a SALES progression, onto bigger better faster MORE in the maker's range, which they would like you to pay for.... personally, I am far from a beginner, I bought an entry level DSLR half a decade or so ago, and see absolutely NO compunction to trade that in for something higher up the model range, with a tilting screen or an extra control wheel or whatever.... it does the job! It takes lenses that are readily available and well priced, and it takes pictures. A-N-D better photographers take better pictures NOT more expensive cameras... if anything is likely to hinder me getting a decent shot, it will NOT be the camera, that is for sure!
So don't sweat the small stuff; the differences between almost any of the current offerings are in the greater scheme of stuff small potatoes, just about ANY Digital Camera made in the last decade will do the job.. whatever that may be in the grand scheme you suggest.... just heed the warnings over Bridge Cameras NOT being the be all and end all, the salesman may suggest, and be wary of the MFT aficionado's applause of the things, that can and do have so many foibles that can make the job of learning photography harder and or more expensive than needs be.
Sorry. if you wanted a nice neat make and model prescription.... B-U-T, like I said, you need to go into a real world shop and get hands on and decide what if more comfy.... just don't get carried away on the sales hype that will likely come with it!
Best of British.