[Heie]

I read your story, and I must say - I am incredibly envious of you! I would KILL to go to the Amazon or Madagascar, especially for the long, sustained periods you were there. Really very envious. And your journey through the camera gear world is a very interesting one, and I am happy to hear you were pointed to Pentax for its weather sealing. I too was in a similar boat looking for cameras, but for a less experienced reason. I never dabbled with photography, but knew because of my personality and my career (I'm in the Army), I needed a camera that would keep up with me. Even those that were constantly pushing the Canon/Nikon route admitted that if you wanted the best build quality you can get for the money (and arguably period), Pentax was the way to go. So I started with the K-7 and never looked back

The bottom line is this, though: I shot in the rain the other day and felt so liberated to have my camera out, without worry.

And it's an incredible feeling, isn't it?. In case you haven't seen this, it should inspire a bit more confidence. Due for an update with my adventures since it's posting, but you get the point

2) I have always wanted lenses with fully uncoated glass for tropical forest work, so that fungus would be a non-issue. Just as a thought experiment, how would uncoated versions of high end lenses perform? How much benefit is really in those organic coatings?

I honestly don't think that you will have an issue with fungus if you stay with sealed lenses. As far as I know (and I could be wrong as I've never had fungus issues and I'm basing this solely off my knowledge of science) - the fungus is from water entering the unsealed, (usually) manual lenses, raising the local humidity level within it. Because the water was now 'trapped' inside, the rate of evaporation was lowered by a very large degree, creating an environment inside the lens that allowed for the development of fungus within it. This is why fungus is never an issue on the outside of lenses but rather inside - the water (vapor or otherwise) on the outside dries too quickly before anything can take root/sprout from it. With the Pentax WR lenses (and especially the DA* and AW lenses, the professional-grade weather sealing that is a bit better than the WR level lenses as it is more rated to also prohibit dust), I think fungus would be an extremely rare occurrence regardless of your circumstances because it simply prevents water from entering the lens/camera to begin with.

There is one caveat to that, though. Rapid temperature change. Because the lenses and camera body is sealed, it does not have the internal airflow that regular lenses have, thus it will raise and lower its internal core temperature at a slower rate than the ambient environment. If there is a stark difference in temperature and humidity, or even just temperature and it will be realized by the camera/lens in a very quick manner (say out in the rainforest all day and then coming inside to an air conditioned building/house or the opposite, shooting outdoors in the winter and then coming inside to a heated building/house), the rapid change in temperature has been known to allow condensation to form (sweating coke cans should come to mind). I've experienced the winter version, but nothing too extreme. Just a little fogging on the inside of my distance scale windows on the DA* lenses, but they usually cleared up within a few hours, the longest was three days (I was worried lol). I've since learned to just leave it in your camera bag and don't open it for a few hours, as the bag will take a while to warm up, doing so slowly (and its contents as well, i.e. your camera gear). Another technique is to place your camera/lens in a plastic bag, seal it, and then the condensation will form on the inside of the bag and not in your camera/lens. I personally have not done this, however it is the standard for many that do very, very cold winter shooting.



As far as lenses go since you are determined for excellent quality as budget allows, this is what my recommendations would be, in order:

1. D FA 100mm f/2.8 Macro WR - a stellar macro lens allowing 1:1 reproduction ratio and in a very compact, all-metal build. You expressed an interest in macro, so that is why I recommend this one first. Weather Sealed.
2. DA* 55 f/1.4 - a stellar portrait/low light lens that will really allow you to capitalize on the K-3's IQ, especially in low light because of its aperture. Weather Sealed.
3. DA* 60-250 - the Pentax zoom lens. Sharp from wide open, it will allow you to get some stunning landscapes and wildlife shots because of its incredible range. Weather Sealed.
4. DA* 16-50 - normally I would recommend this lens much earlier, but by now (assuming you listen to me ) you would have the DA 18-135 and the DA* 55, allowing for a very low light lens and the weather sealed standard zoom (18-135 WR). Weather Sealed.

And whenever, I would also recommend the following: Sirui T-025x Travel Tripod. I wrote this review, so I can confirm that everything said in it is true according to my own experiences But seriously, as a hiker/outdoorsman not using large tele lenses, this is the tripod as far as I'm concerned.

Hope this helps, and welcome

-Heie

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Last edited by Heie; 12-04-2013 at 04:25 AM. Reason: typo :)

[BretW]

I read your story, and I must say - I am incredibly envious of you! I would KILL to go to the Amazon or Madagascar, especially for the long, sustained periods you were there. Really very envious. And your journey through the camera gear world is a very interesting one, and I am happy to hear you were pointed to Pentax for its weather sealing. I too was in a similar boat looking for cameras, but for a less experienced reason. I never dabbled with photography, but knew because of my personality and my career (I'm in the Army), I needed a camera that would keep up with me. Even those that were constantly pushing the Canon/Nikon route admitted that if you wanted the best build quality you can get for the money (and arguably period), Pentax was the way to go. So I started with the K-7 and never looked back



And it's an incredible feeling, isn't it?. In case you haven't seen this, it should inspire a bit more confidence. Due for an update with my adventures since it's posting, but you get the point


I honestly don't think that you will have an issue with fungus if you stay with sealed lenses. As far as I know (and I could be wrong as I've never had fungus issues and I'm basing this solely off my knowledge of science) - the fungus is from water entering the unsealed, (usually) manual lenses, raising the local humidity level within it. Because the water was now 'trapped' inside, the rate of evaporation was lowered by a very large degree, creating an environment inside the lens that allowed for the development of fungus within it. This is why fungus is never an issue on the outside of lenses but rather inside - the water (vapor or otherwise) on the outside dries too quickly before anything can take root/sprout from it. With the Pentax WR lenses (and especially the DA* and AW lenses, the professional-grade weather sealing that is a bit better than the WR level lenses as it is more rated to also prohibit dust), I think fungus would be an extremely rare occurrence regardless of your circumstances because it simply prevents water from entering the lens/camera to begin with.

There is one caveat to that, though. Rapid temperature change. Because the lenses and camera body is sealed, it does not have the internal airflow that regular lenses have, thus it will raise and lower its internal core temperature at a slower rate than the ambient environment. If there is a stark difference in temperature and humidity, or even just temperature and it will be realized by the camera/lens in a very quick manner (say out in the rainforest all day and then coming inside to an air conditioned building/house or the opposite, shooting outdoors in the winter and then coming inside to a heated building/house), the rapid change in temperature has been known to allow condensation to form (sweating coke cans should come to mind). I've experienced the winter version, but nothing too extreme. Just a little fogging on the inside of my distance scale windows on the DA* lenses, but they usually cleared up within a few hours, the longest was three days (I was worried lol). I've since learned to just leave it in your camera bag and don't open it for a few hours, as the bag will take a while to warm up, doing so slowly (and its contents as well, i.e. your camera gear). Another technique is to place your camera/lens in a plastic bag, seal it, and then the condensation will form on the inside of the bag and not in your camera/lens. I personally have not done this, however it is the standard for many that do very, very cold winter shooting.



As far as lenses go since you are determined for excellent quality as budget allows, this is what my recommendations would be, in order:

1. D FA 100mm f/2.8 Macro WR - a stellar macro lens allowing 1:1 reproduction ratio and in a very compact, all-metal build. You expressed an interest in macro, so that is why I recommend this one first. Weather Sealed.
2. DA* 55 f/1.4 - a stellar portrait/low light lens that will really allow you to capitalize on the K-3's IQ, especially in low light because of its aperture. Weather Sealed.
3. DA* 60-250 - the Pentax zoom lens. Sharp from wide open, it will allow you to get some stunning landscapes and wildlife shots because of its incredible range. Weather Sealed.
4. DA* 16-50 - normally I would recommend this lens much earlier, but by now (assuming you listen to me ) you would have the DA 18-135 and the DA* 55, allowing for a very low light lens and the weather sealed standard zoom (18-135 WR). Weather Sealed.

And whenever, I would also recommend the following: Sirui T-025x Travel Tripod. I wrote this review, so I can confirm that everything said in it is true according to my own experiences But seriously, as a hiker/outdoorsman not using large tele lenses, this is the tripod as far as I'm concerned.

Hope this helps, and welcome

-Heie

Yes, that is really informative. Thank you for putting the time and effort into your reply, Heie. It helps a lot.

It does raise a question in my mind, though. The water sealing of the lenses does risk trapping moisture that has condensed internally, just as you suggest. That could be a big problem in a tropical field station situation where "dry rooms" are often air conditioned to dehumidify them. Take a cold WR lens out into the warm forest and it will frequently fog up until it warms to the ambient temp. That is a familiar hazard. But that may take a very long while on a sealed lens if there is no ability for warm air to circulate. And it might be especially bad on a lens that changes volume with zoom, thereby sucking in moist ambient air. Or it might be better because the zoom could allow effective pumping of air through the lens to warm it up and defog it.

Bottom line is that a "dry closet" (heated with a lightbulb) is almost certainly better in tropical forest conditions than a cold room. And if there is only a cold room, one should probably give weather sealed zooms plenty of time to warm up before zooming them in the telephoto direction.

[BretW]

Thanks to Class A as well. I'm still trying to wrap my mind around your explanation on FF and sensitivity. I think it is consistent with what I meant to imply, but I'm not sure. It has the same net effect, I think, but i'm struggling to figure out the details of what constraints a smaller sensor imposes on lens design. I will read the link and perhaps post a follow up in the appropriate forum.