[arniejrim]

Guys,

I have a Pentax K10D and need a good lens for taking wildlife pictures.

Mainly they are dolphins - so shots of fast moving animals taken from a moving ship at a distance of 800m to 2km, at sea (so some glare)

I've narrowed it down to either:

- Sigma 150-500mm f/5-6.3 DG HSM

or

- 2nd hand Sigma 100-300mm f/4 EX DG IF HSM APO with Sigma 1.4x EX DG Tele Converter

I'm guessing a good quality CPL filter would be a good idea too.

I've already tried shots with a Tamron 70-300mm F/4-5.6 Di LD Macro but the results arn't great, often grainy or not sharp.

Any recommendations?

Cheers.

[Digitalis]

Firstly; forget the circular polarizer, I never use them on lenses longer than 100mm - they drop the shutter speeds too far for hand holding, even though Pentax DSLR's have built in IS I personally don't have much faith in it when using lenses longer than 300mm. Though considering the environment you are working under you might want to invest in a UV/protective filter to prevent salt sea spray from getting on the front element of your lens, it can be a real pain to clean off in some cases.

The sigma 50-500mm f/5.6-6.3 EX DG or it's handle: "The Bigma" is a big,slow,lens which means you're most likely to be cranking up the ISO in order to keep the set-up hand-holdable which is counter-productive to maintaining high quality images. I consider the absolute limit for the K10D is ISO 800 with the aid of meticulous exposure you can produce images or reasonably high quality but that requires alot of skill to achieve. With such a slow aperture it takes some stopping down to make high resolution images,providing camera shake isn't a problem. A f/6.3 lens usually hits it's resolution peak f/13 at 500mm which doesn't leave much room for hand holdability I haven't seen many images taken with the bigma wide open...I suspect there is a pretty good reason for that.. and considering the environment that you will be working under I certainly wouldn't recommend the Bigma.

I'll admit I'm biased towards your second choice...and for good reason: The Sigma 100-300mm f/4 EX DG is a moderate speed, but extremely useful lens. it focuses very quickly, due to it's short focus throw. I have noted it's resolution peak is achieved at f/8 where it capable of producing images that are indistinguishable from my Pentax 300mm f/2.8 prime lens at the same aperture. But on that note, I have produced many images with the lens wide open at f/4 where only the closest scrutiny would reveal any difference in image quality, a truly remarkable ability. Plus the added versatility of a zoom, I prefer zoom lenses that stay within a "golden ratio" of 1:3 - because lenses that go beyond that magnification ratio are (often) optically inferior to their more conservative cousins. Because lenses like that are difficult to make, and mistakes and compromises are made. However, the sigma 100-300mm even when used with a teleconverter is excellent...Tamron Teleconverters are the make commonly used because the Sigma ones don't seem to be quite as sharp for some reason, and they don't report the multiplied focal length of the teleconverter+lens combination correctly.

however there is one area where sigma lenses don't do well in and that is dealing with flare...they are all very succeptible to it, and it can completely ruin a shot if you don't spot it quickly. I'm afraid even the lens hoods can prove completely useless in certain scenarios but, they are better than nothing, which would be worse. Plus they protect the front lens element from salt sea spray which can cause even more problems with flare.

You might also want to invest in a monopod. look into either a manfrotto or gitzo. both makers offer many different models however the price goes up in accordance with how high the monopod extends..being tall comes at a price.

[Just1MoreDave]

Out of curiosity, I decided to see what 800 meters looks like at various focal lengths. The car just off center in these shots is just about that far away. They are taken with a Vivitar T4 300mm f5.5, a Tokina SD 400mm f5.6 and a Vivitar 500mm f8 mirror. The warehouse in the far background is maybe 1km.





What's a dolphin, 3 meters long? So 500mm is a minimum, you might consider an 800mm mirror.

[Miguel]

Trying to capture distant objects from a moving vessel with a DSLR and a heavy, slow, long lens is a waste of money and energy. You'll get out-of-focus images and not be able to enjoy seeing the dolphins in real time.

Put the $1200 into a nice video cam that has a good optic or a Zeiss spotting scope that you can use for birds and wildlife later.
You can always attach the Pentax via T-mount to most telescopes.

M

[Marc Sabatella]

I've already tried shots with a Tamron 70-300mm F/4-5.6 Di LD Macro but the results arn't great, often grainy or not sharp.

Not sure what your level of expertise is, so sorry if I'm totally off base here, but:

Lenses don't cause graininess. That comes from using high ISO, which in turn comes from not having a large enough aperture to get you the shutter speed you want. And if f/5.6 is the maximum aperture of this lens, the other lenses you mention aren't going to help, unless you use the Sigma 100-300 *without* the TC, in which case you do get one stop advtanage at least. However, it's going to be so much bigger and harder to hold, you might easily lose that advantage. Similarly, without seeing pictures to judge from or knowing more about your level of expertise, my guess would be the lack of sharpness is not because the lens isn't sharp enough, but simply because you aren't getting fast enough shutter speeds to stop the motion of the dolphin (or perhaps indeed to stop the motion of the boat and/or your hands - SR can't work miracles).

Bottom line is: I wouldn't expect a better/longer lens to suddenly make your problems go away. You're going to be fighting hard to get a steady enoguh shot at a fast enough shutter speed to stop motion. If I were you, I'd concentrate on first mastering use of the 70-300 (again, apologies if you're already way beyond what I'm saying, but you didn't give us much to go on) as far as how to find the optimum balance between aperture, shutter speed, and ISO to get the best shots you can from it. And then reconsider you what new lens might help, taking into consideration how much of what you are fighting is not a large enough maximum aperture versus difficulty getting steady (are you using a tripod? Does one even make sense on a moving boat?) versus the lens itself not being long enough versus not being sharp enough.

[GLXLR]

I think the Sigma 100-300mm f/4+ teleconverter (despite the converter on it) will give you the best results IQ wise.
Like someone said, an 800 mirror lens might be considered, but from the wild life images I have seen from the DA* 300mm f/4, 300mm might be enough. 800mm to me seems rediculously long, but of course, I have no experience with lenses longer than 200mm so take my comment with a grain of salt.

[philbaum]

I don't think you said what kind of ship you will be on. Our local ferrys, which can carry up to 40-50 cars, vibrate constantly. You can feel the vibrations right through your feet, the whole superstructure vibrates. Tripods and monopods don't work well on such ships because they just transmit the vibration into your camera/lens. I've heard of photographers who will photograph on the balls of their feet, rather than let vibrations go up through the heels.

If its a whale watching ship that is going to quiet its props or engine, than one would have more of a chance.

I think something like a video camera as someone suggested would make more sense. I'd be cautious of buying something too specialized for this application, unless you have other use for it. I gave up on bird photography when i found out what was going to be required to "do it right". One of the best decisions i ever made.

best wishes whatever you decide,

[Douglas_of_Sweden]

Welcome to the forum!

I'm not a great authority on long glass, but you have certainly got some good advice here:

-forget about the polarizer, it steel light you need for the speed
-you need a fast lens to get short enough shutter time to get sharp pictures and low enough iso to avoid the "grain": the old rule would have been that 300mm required 1/300 second or less, 400mm 1/400 sec or less etc. SR changed this a bit but...SR does not work well on moving platforms, and here you don't only have the ship speed, but also the sea motions (on the order of 10 second periods) and the engine-vibrations (on the order of 0.1 seconds or shorter)...a hell for the SR to compensate for...so probably you have to turn SR off and you are back at the old rule, and with the slowish lenses you have listed, this means high iso and lots of "grain". I don't think you can get away with less than f4.
-monopod might help...though it may transfer more of the vibrations than your body would, tripod is probably no good since it will have your camera follow every ship motion

One question here: dolphins are often not very shy...they like to swim close to the ship...why do you have to shoot them so far away? Why not just shoot them when they ride the surge or swim ahead of the bow as close as possible?

When you say you tried that Tamron lens, was that at sea, over those distances on doplhins or similarly sized objects?.

You might get some more qualified info and more example of possible lenses on the 300mm plus lens club.

[Digitalis]

Tripods and monopods don't work well on such ships because they just transmit the vibration into your camera/lens. I've heard of photographers who will photograph on the balls of their feet, rather than let vibrations go up through the heels.

I seem to recall carbon fibre monopods are better at dealing with this than their metal counterparts, however you pay through the nose for such novelty.

[AdrianM]

I own a Sigma 100-300 f4 and am currently borrowing a Bigma (Sigma 50-500) to make a comparison. I usually use the 100-300 with a teleconverter (to date generally the Sigma 1.4x TC, but have just acquired a Kenko 1.5x TC). What I found is:
- the difference in angle of view at max focal length is negligible
- 100-300 with tele provides a better photo because of larger aperture hence lower ISO or higher speed
- without the tele, the 100-300 works in even lower light
- Overall, I feel I get better shots and better flexibility from the 100-300 with a TC than the 50-500.
- Although I have been happy with the optical quality of the Sigma tele, I have just broken my second one. The pins drop and get stuck all too easily and the structure is not as robust as it needs to be. I have just started with the Kenko and so far no problems, but only time will tell.

Out of all of that, I just decided to buy the Pentax DA*300 with a Kenko SHQ tele to supplement the 100-300. Why - because it is lighter for hiking and will be very useful for birds which usually require only one focal length (the long one). I will still be using the 100-300 for sport, aircraft and a range of other general stuff where weight or zoom is not so important.