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Hello everyone,

I plan to go to the Mississippi delta and take some long range shots of the nearby offshore oil platforms before sunrise. These things are quite alien and imposing, and look even more so in the dark with all of their lights on. I will probably need something in the 500mm range or so that has as little purple fringing as possible. I will shoot from a tripod in RAW on a stable structure, and I guess the exposure will have to last several seconds. Would I be better off with a dedicated lens, a telescope with a K mount, or something else?

Thanks,
John

[-spam-]

Seems like the sigma 50-500 on a tripod would suit your needs quite well. Im thinking about getting this lens but for motor sports, just waiting on a few opinions with using it with pentax first.

[SupremeMoFo]

Im thinking about getting this lens but for motor sports,

NOPE! Too big, too heavy, too slow. You'd be relying on ISO400+ to get the shutter speeds you want even in broad daylight. I'm getting the Pentax DA*50-135 f2.8 for motorsport.

50-500 would be pretty good for this though.

[Falcons]

I would think the Sigma (Bigma) would be your most logical choice for what you want to achieve.

Spam, I was talking to one of the team photographers (for the V8 Utes)at the V8 Supercars when they were in Perth. He was using a Canon 20d with a 70 - 200L - he said this was his main lens he also had the Bigma but said he very rarely used it as it was slower and 500mm was just too much for most shots.

[button]

Seems like the sigma 50-500 on a tripod would suit your needs quite well.

I would think the Sigma (Bigma) would be your most logical choice for what you want to achieve.

Thanks, guys. Does anyone have any experience with this lens with regard to night photography? In my case, I'll probably be at or near 500mm at f6.3 and ISO 100. I'm guessing I'll need anywhere from 20-50 seconds for the exposure.

[roentarre]

I definitely recommend against its use in night time shooting. At the long end (500mm), motion blurr is inevitable even on tripod. Using this lens wide open f6.3 at 500mm is often softer; stopping down one stop is usually recommended.

However, bigma is the "lightest" big zoom lens with great image quality around. The only problem is the fact that this lens is simply often too dark to use unless the day is bright. You would need relatively fast speed (Faster than 1/500 sec) to freeze action with minimum aperture of f8.

[button]

I definitely recommend against its use in night time shooting. At the long end (500mm), motion blurr is inevitable even on tripod.

I guess the motion blur at 500mm during a long exposure would come from wind (if any) and vibration from mirror flip up. I was going to use a heavy tripod and up to a 12 second delay for the shot (to get the mirror up and allow adequate time for vibrational dampening). In this case, I wonder if SR would actually help on a tripod. Would these techniques work? I really want to get this shot, but I don't think I can find a stable structure closer than about 3-4 miles from these oil rigs. Any other ideas? Roentarre, can you try a 12s delayed 500mm 30-40 second shot on a tripod at night of a well lit building, both with and without SR? I'd really like to see what those pictures look like. Please post if you can.

Thanks,
John

[little laker]

Just my opinion that a beanbag would be better for such photo's, although harder to aim. It shouldn't be as effected by the wind.

On top of a picnic table, or something stable. Using a remote control (a fraction of the cost of the lens) will eliminate the need for a 12 second delay.

In this case I think that you'd still have some movement from the rigs themselves, and if there's any sort of spray blowing around off shore it could really mess things up.

Personally I think that you'd have a better chance of getting the perfect photo by convincing someone with a fair sized boat taking you out for a while, and using a smaller lens (Sigma 70-300 APO)

[GaryML]

Hello everyone,

I plan to go to the Mississippi delta and take some long range shots of the nearby offshore oil platforms before sunrise. These things are quite alien and imposing, and look even more so in the dark with all of their lights on. I will probably need something in the 500mm range or so that has as little purple fringing as possible. I will shoot from a tripod in RAW on a stable structure, and I guess the exposure will have to last several seconds. Would I be better off with a dedicated lens, a telescope with a K mount, or something else?

Your best bet (i.e., best image quality) is a long, fixed focal length lens like a 500mm or 600mm f4, with matched teleconverters (1.4X, 1.7X, and/or 2X). Unfortunately, there is nothing like this available for the Pentax mount. If your budget permits, both Nikon and Canon make such lenses and tele-converters. And both have shake reduction systems that will work properly with tripod use (which is not the case with Pentax SR). Of course, you will also need a suitable camera body (film or digital) to go with the lenses. Pentax does a great job for many applications, but this is not one of them.

Alternatively, you can look for a suitable used lens for the Pentax (vary rare and expensive). The SMC (K/M/A) 400mm f5.6 is probably the most common and least expensive, but it doesn't have ED glass so CA might be a problem.

Another alternative is a small celestial telescope or spotting scope, and use a T-mount and adapter. The problem with using a telescope is that they are usually quite slow. For example, the venerable Celestron C90 can be used as a 1200mm lens at f13.3. Not the best for low-light applications, but it can be made to work, and the C90 is only $200. There are faster telescopes like the Tele-vue 102 (880mm f8.6). It is $2,700 (about 1/2 the price of a big lens from Canon or Nikon) but still pretty slow. Note that mirror 'scopes will give you the "doughnut" out-of focus highlights. The Tele-vue is a refractor so it doesn't have this issue.

[Adam]

Pentax has quite a few big guns, but they're all out of production

The K 500mm F4.5 is relatively easy to find on the used market and would probably be your best bet if you want to pay around $600. It's got some pretty heavy green fringing, unfortunately.

I've seen A 400mm F5.6 go for more than the above 500mm, but as long as I've used mine I've never encountered noticeable CA. Despite not having ED glass, this is probably because the A has 7 elements while the K only has 4.

Another great combo is the FA* 300mm/2.8 + the A 2x-L converter, resulting in a sharp 600mm F5.6. It goes for 3-4k, though

[Lowell Goudge]

My favourite long lens combination is the Pentax 300 mm F4 (k mount) with the 1.7 x autofocus adaptor.

Drawbacks are, it is F 6.8 maximum, and no tripod mount, although I have made one for it.

Avoid using a telescope for night shots, as you will get a lot of out of focus donuts fromt he secondary mirror that blocks the central portion of the field of view. I use a C 90 for some shots, but you have to like donuts.

Other options are any 400 mm F5.6 providing there is a tripod mount. or some of the new 500 mm zooms, it depends upon how much you want to pay.

Regarding shake, what you really need to consider is how to weight down your tripod. I generally hang my camera bag off the tripod

[button]

Just my opinion that a beanbag would be better for such photo's, although harder to aim. It shouldn't be as effected by the wind.

On top of a picnic table, or something stable. Using a remote control (a fraction of the cost of the lens) will eliminate the need for a 12 second delay.

In this case I think that you'd still have some movement from the rigs themselves, and if there's any sort of spray blowing around off shore it could really mess things up.

Personally I think that you'd have a better chance of getting the perfect photo by convincing someone with a fair sized boat taking you out for a while, and using a smaller lens (Sigma 70-300 APO)

I'll be on a 27 foot boat (no yacht by any stretch of the imagination), and we can get as close to the rig as we want. The waves inside the delta are usually negligible, so maybe a handheld shot with SR could work. I have a 31mm ltd, an FA 50mm 1:1.4, a 77mm ltd and an A* 85mm 1:1.4. Wide open, maybe I might have a chance of a fast exposure (given the amount of artificial light coming off of the rig) especially with the 31mm or the 50mm. The perspective at close range would be more desirable anyway, as I want the rig to look like it's towering over the viewer. Any of you folks ever taken night shots off of a boat? Any ideas for maximum stabilization?

John

[little laker]

When are you going on the trip John?

The reason why I'm asking is because I'll be on an ocean going 27' Catalina the first weekend in June.

And I won't be able to resist trying some night photography from it, so I( might have some tips for you then.
Or I might be able to try a few things on my trip then if you have any ideas you want tested.

My trip is just for fun, and will probably cost me a whole lot less than yours, so i don't mind experimenting a little.

[button]

When are you going on the trip John?

The reason why I'm asking is because I'll be on an ocean going 27' Catalina the first weekend in June.

My trip probably won't happen until later this year, so I would certainly benefit from your experience- it sounds like a lot of fun!

[GaryML]

I'll be on a 27 foot boat (no yacht by any stretch of the imagination), and we can get as close to the rig as we want. The waves inside the delta are usually negligible, so maybe a handheld shot with SR could work. I have a 31mm ltd, an FA 50mm 1:1.4, a 77mm ltd and an A* 85mm 1:1.4. Wide open, maybe I might have a chance of a fast exposure (given the amount of artificial light coming off of the rig) especially with the 31mm or the 50mm. The perspective at close range would be more desirable anyway, as I want the rig to look like it's towering over the viewer. Any of you folks ever taken night shots off of a boat? Any ideas for maximum stabilization?

John

Well, you didn't state in your original post that you were going to be on a boat. That makes a huge difference. I have taken photos off a boat, but not past twilight.

Forget the super-long lenses: get in as close as prudent, use a tripod or other support, and use the fastest lens available for the field of view needed. Since the boat is moving any long exposure will be blurred, so you want the fastest shutter speed you can get. You can experiment with SR on and off, but a tripod on a boat is going to be better than hand-held even with SR. You can also try bracing the camera against a railing or similar structure on the boat. Be sure the boat's motor is OFF when shooting.