[aslyfox]

DA-L plastic mount
DA metal mount
DA WR Water resistant, better coatings less aberrations
PLM as above plus faster AF . . .

for information on all of the Pentax K mount lenses series, I suggest this chart

Pentax K-Mount Lens Series Explained: The differences between various Pentax lens series

In a nutshell
There are several series of Pentax K-mount lenses; the ones currently being produced include the DA (digital), DA L (cheap digital kit), D FA (full-frame, digital optimized), and FA (full-frame) series. While all Pentax K-mount lenses ever produced are compatible with all current Pentax DSLRs (in some cases with restrictions in that not all exposure modes of the camera are supported by old lenses), there are significant differences between each lens series and each has different features. Furthermore some of the newer lenses do not work with older cameras. We'll be exploring the differences between the various K-mount series lenses in this article . . .

Pentax K-Mount Lenses Explained: The differences between various Pentax lens series

[Des]

I have just joined a friend who has Nikon set up and she likes to go out to take pictures of nature. She enjoys to shoot whales, birds, dogs, horses and other animals. Most of her pics are at a distance due to necessity.

Much depends on the distance and the size of the subject.

If you are talking about a small bird more than 20m away, a 300mm lens is nowhere near enough. But for a medium-large bird within 10m, like this heron, it is.

(Taken with the K-S2 + DA-L 55-300, a $100 lens.)

With a large animal (e.g. a horse or cattle), 300mm is often more than enough. This photo was taken from a safe distance (with a K-S2 and DA 55-300 PLM) at 260mm.


If you are photographing whales on a cruise, they sometimes come close enough that a long lens is not necessary. I got this humpback with a DA 18-135 at 31mm.


And this one with the PLM at 108mm


But if you are photographing from the shore, you would generally need more than 300mm to get a worthwhile shot.

What I'd say is: start with your F 100-300mm and see how you go. If 300mm is adequate for your needs you could persist with the 100-300 until you are able to upgrade to the 55-300 PLM (or, if that is out of range, one of the screwdriven-AF 55-300 f4-5.8 models). As others have said, anything longer than 300mm (especially with autofocus) will involve a big jump in cost and weight.

I haven't used the F100-300, but in general these sorts of zooms do best stopped down to f8 (or even f11). Try using TAv with the shutter speed at 1/500th or faster and the aperture at f8 and let the ISO float up to 3200. If that isn't enough for the available light, try dropping the shutter to say 1/250th first; then the aperture.

Technique matters. I'd suggest reading this article and working on these skills: Making the Most of Long Exposure Handhelds - Introduction - In-Depth Articles

[mikesbike]

Another consideration, if 300mm is just a bit shorter than optimum, like if you had 400mm that would do it, and only for a minority of shots, yet if your lens quality is good, preferably better than your 100-300 lens, you could just do some cropping in post process. Your K-S2 is in the higher resolution category, so its imaging can handle some cropping if with a good lens.

[Wasp]

A 400mm manual focus with a teleconverter of your choice will not break the bank. I have the SMC Pentax A 400mm f/5.6 which gives me that extra reach that is lacking in my 300mm zooms (of which I have four but that is another story). To be honest, going from 300mm to 400mm is not a big jump and a teleconverter is in order. For more reach I add the SMC Pentax Rear Converter A 1.4x-L. For something that will autofocus with the 400mm (in good light) I use the SMC Pentax F 1.7x AF Converter.

[Lowell Goudge]

I will start backwards with this post. Where I am now in a quest for a lens for birding and nature.

My current kit includes a K1 MK2 And a DA 560 / 5.6

Ok I get it , not cheap

So let’s look at the path of how I got there.

For many years, I shot a mix of two lenses, the K300/4 paired with an SMC F 1.7x converter, and a Sigma APO 70-200/2.8 EX and sigma 2x teleconverter.

Mixed in with these 2 options is a Tamron 200-500/5.6 adaptall

Overall, the sigma zoom (and note this lens is a film lens not one optimized for digital) Wins for overall sharpness, when it hits focus, But AF is not absolute, due to the backlash of screw drive and teleconverter. It also suffers a little from sharpness at extreme distance,

The K300/4 and AF converter is the lightest 500mm option you will ever get, at about 1.1 kilos total. Relatively sharp, it suffers a little from fringing but works well in good light otherwise.

The Tammy is very good, but does not suit my style of birding for walking. It is tripod bound, has terrible weight distribution from the tripod mount (due to the position of the mount, zooming ring and focus ring) And is awkward to use even on a monopod. It also suffers badly from purple fringing. So it needs the most post processing. Note it pairs well with 1.4 and 2 x TCs to get a ton of reach.

The op needs to decide what type of birding he wants to do, but I will offer my advise.

Get AutoFocus some how, because manual focus is too slow for all but great big birds like herons.

Get as long as you can. Remember birds like a heron are about 500mm to 1 meter tall and are easy to fill a frame, try the other end of the spectrum, warblers and finches, which are typically 100mm end to end, you are never close enough.

Get as fast as you can, because shooting small birds envariably has you working in the shadows, under foliage.

Be prepared to let the ISO go as high as you can accept. I let my K1 and K5 go to 10000. I’d Rather Accept the grain than give up a shot because I can’t shoot iso 100,

Consider a flash, it actually does not bother the birds that much. It also ads sharpness because the flash duration is in the order of microseconds and freezes the subject

If you go with your friend go light ( I know, not really possible)

Boiling all this down leads to something like an A300/4 plus AF converter, or a DA300/4 with 1.4 x converter. The reason I suggest the A300/4 Over the K300/4 that I have is the aperture control. It lets you use a flash.

You might get a sigma 500 mm zoom, there are several from the BIGMA 50-500] to a couple of different offerings in the 150/170 - 500 mm range. I have never used one personally so I can’t comment on their sharpness at 500mm

You might also look for the older sigma AF zooms 100-300/4 or 120-400/5.6 zooms used.or if budget permits the DFA150-450

If you can afford it get a lens with internal focusing motor, focus acquisition is more positive than screw drive.

Lastly don’t be afraid to crop.

You only need 3-4 MP to get a stunning photograph at A4 size and remember one simple formula

Image size = subject size x focal length / distance

Consider your APS-C sensor and try to fill it with a 100mm high finch. To fill the frame would require you to be about 2m away from the camera(front of the lens) with a 500 mm lens. It will never happen Sure a heron is simple but that’s not what the Op is going to shoot. As a result everything you do will be a crop.

I don’t know the sensor for the OP well enough to judge the trade of low light vs MP resolution. But likely he can crop to 1/10 of the frame area and still print and have a nice shot,

The biggest issue is his definition of cheap. Every option I have suggested, will set the OP back about $500-$2000 Canadian minimum. Except the DA560 of course. Which is more. While some suggest you can get by with 300 mm and less than $100 that will work fine for a backyard feeder maybe, but not for being out and about.

[MikeMcE]

Lowell, that is superb advice.


Hang up and DRIVE!

[Lowell Goudge]

Lowell, that is superb advice.


Hang up and DRIVE!

Thanks, one thing I forgot. Be fit. Stay fit. I know it is not easy.

I have seen a ton of posts in the past, looking for super light because Their medical/physical conditions don’t permit holding heavy lenses. I can understand this and the gear also has to suit your life style

Your health and general fitness are everything. Note i shoot today a lot with a K1 and DA 560. This pairing comes in at About 5 kilos. I shoot hand held exclusively, and a typical walk is 5 km with this lens over my shoulder ready to shoot. If I was not able to do this, my current gear would be useless. I would likely settle for some form of bridge camera

That is the other option, an ILC camera like the Q and a good 200mm lens. With the form factor, 200mm is about 1000 mm compared to full frame, and there are a ton of MF 200 mm lenses out there, some better than others, but still useable. A Q with a viewing screen cover And eyepiece (I use one for a Nikon) let’s you manual focus on even the brightest days. There are others with spotting scopes and eye piece adaptors for p&s cameras. Again for stationary birding not too bad

[cometguy]

I don't have the f/4.5-5.6 version, but I have the F 100-300mm f/4.7-5.8 version (which is supposed to be somewhat better, as per reviews at this forum).
Nonetheless, below is a close-up crop screenshot of a photo that I took a couple months ago of a red-tailed hawk with my K10D camera and that lens at 300mm and f/5.8, hand-held. It is an excellent lens optically, despite its plasticky looks and feel, for a long-range zoom. In the original image, I can see lots of detail in the beak and feathers, even though I missed perfect focus by just a bit (the bird flew away before I had time to get a tripod out).

I also have one of the early Vivitar 1 series 70-210mm lenses, and it also has relatively sharp optics and a much better build than the 100-300mm lens (though zoom creep is bad), and as a zoom lens it is much easier to zoom quickly and easier to manual focus than is the F 100-300mm lens -- although its reach at 210mm is not so far.

[aslyfox]

Consider a flash, it actually does not bother the birds that much. It also ads sharpness because the flash duration is in the order of microseconds and freezes the subject . . .

several responses have mentioned the advantage of using a flash:

Flash Extenders
Before we discuss when and how to use your flash for bird photography, let's talk about the limitation that most flash units have – their effective range. Getting close enough to a bird to be within that range can be difficult. As noted in an earlier lesson, a simple flash extender won't set you back much financially and may be one of the best investments you can make for supplementing the light in those telephoto shots. Keep in mind that leaving the extender on in bright sunlight calls for some caution, as the lens can cause heat damage to your equipment.

Here are a few of the ways that using a flash may help improve your bird photos:. . .

Bird Photography Basics: Using a Flash

_________________

I just returned from an assignment photographing birds in Texas for an upcoming magazine story. Contrary to what I expected, we didn’t get endless sunny days. Instead, cool wet weather was the norm. This diffused light is great for photographing birds; less contrast, saturated colors and you can shoot all day. But you loose the warm light and specular catchlights sunny days provide. If you don’t like the light, then make your own light!

I decided to use a speedlight with flash extender to add just a kiss of light to some of my bird images. . . .

https://www.tombolphoto.com/flash-extenders/

[ChristianRock]

Another suggestion is the lens I just bought yesterday... FA 80-320mm f/4.5-5.6 - especially if you're not going to shoot at the 320mm end all that much (it's not my intention, either). From 80-200mm and in somewhat good light, it's supposedly very, very good. The DA 55-300 versions might be a bit better technically, but I really like the color rendering and the contrast of that old FA lens.
As recommended here, I also bought a lens hood for that 80-320mm lens...