New Equipment

[skitterbug]

Thank you for taking time to post about your experiences! I looked a little bit at Nikon but since the gear I currently have is Canon, I stayed with it. I can use my older lenses with the new camera as well since I decided to get a cropped one. Also I did go with a refurbished camera body, so I haven't blown my entire camera budget out of the water yet! <LOL> I hope I did pick the right model but I guess only time and experience with it will tell. It is definitely a step above my current Rebel t3i.

It sounds like you have made the right choice going in the direction that you have. And you are spot on that these choices boil down to personal preference and maybe knowledge gained over time helps as well! I especially was appreciative of all the support and knowledge shared by the CiC group. They are very generous with their time and experiences!

I've used the plastic bag idea before but my problem seems to come when I head from the warm house to the outside cold weather. There has been a bit of discussion about what might have cause this and what I can maybe do to keep it from happening.

I hope you will post some of your photo work! I love to see it! And welcome! This is a fun "place" to take part in!

Hello. I recently resolved this same dilemma for myself. My first DSLR with interchangeable lenses was a crop sensor Nikon D70S. From there I went to another crop sensor the Nikon D7100. A few days ago I purchased my first full frame DSLR, a Nikon D810. Yes, it is a bit weighty especially with the Sigma 24-70mm f2.8 art lens attached. I felt this was a good choice for me as the Nikon D750 in my opinion is somewhat the same as the D7100 except it is a full frame, not a crop sensor as the D7100 is.
It all comes down to personal preference...what you are shooting...your equipment budget, etc. No, it was not an easy decision. With all the holiday sales going on and free items included, it is a good time to be purchasing camera gear...in my opinion.
As for your concern regarding condensation in cold weather. I live in Alaska and do ice sculpture photography. Prior to coming back into the warm house, my camera is placed in a plastic bag and tightly closed. This prevents condensation from forming on the camera and lens. There are several sites that sell camera jackets but be sure to check their temperature ratings....most are not rated for the Alaska cold.
Good luck with your decision. I will look back on this forum for updates.

[skitterbug]

Hi Ted - Thanks for sharing this information. I couldn't seem to pull out the info so it makes me think that it isn't available in a readable manner to me. I suppose the Canon people would have a way to figure it out?

I guess I am going to have to trust that what I am getting isn't overly used! I'll still probably take a pic and post it to one of those sites that is supposed to be able to tell me such stuff and see what happens. Probably it will be another pic of the kitchen cupboard! <LOL>

Enjoy your Texas weather! It is bitter cold here tonight! <brrrr>

[george013]

.....
I've used the plastic bag idea before but my problem seems to come when I head from the warm house to the outside cold weather. There has been a bit of discussion about what might have cause this and what I can maybe do to keep it from happening.
......

There wasn't a discussion of what might have caused this. That's the air getting colder. And that happens first on places with the less heat resistance: your glass. I don't believe in the barrel thoughts of Dan. Thin plastic is more for cheaper kit lenses.

You still have the camera and it's still winter. Go outside, take of the lens and let the cold air replace the warm air in the camera. Just the opposite from using your plastic bag. Depending on the lens you might zoom or focus with it to create some wind internal.
Another solution might be to save the gear once in a bag with rice. Lens off the camera. That will take the vapor out of the air. Then while in the bag put the lens on the camera and just go outside. You may even think of doing the bag trick on a cold place. The colder the air, the less vapor it can contain. Rice is mostly available or if you have some of those special bags you use them.
If that works the you know in what direction you've to look for a definitive solution.

George

[xpatUSA]

There wasn't a discussion of what might have caused this. That's the air getting colder. And that happens first on places with the less heat resistance: your glass. I don't believe in the barrel thoughts of Dan. Thin plastic is more for cheaper kit lenses.

George, if you don't believe Dan, why don't you prove your disbelief with some formulae, numbers and illustrations - instead of just unspecific wording?

Let's discuss a 70mm dia single object lens 10mm thick, on average in a body, 100mm long, 2mm thick.

a) thin plastic body
b) magnesium alloy body
c) aluminum body.

The assembly to be placed on insulating foam so as to avoid discussion of the rear lens cap.

To help you along, here is the thermal conductivity k (not resistance, not conductance, not 'R' value) of some materials:

glass 1.05 W/(m.K)
Polycarbonate 0.19 W/(m.K)
Aluminum 205 W/(m.K)
Magnesium Alloy 70-145 W/(m.K),

where W=Watt=Joule/sec (a hint: because time is involved).

https://www.engineeringtoolbox.com/t...ity-d_429.html

Shouldn't be too hard for a man of your caliber.

Meanwhile ...

[george013]

If you don't believe Dan, why don't you prove your disbelief with some formulae, numbers and illustrations - instead of just words?

To help you along, here is the thermal conductivity (not resistance, not conductance, not 'R' value) of some materials:

glass 1.05 W/(m.K)
Polycarbonate 0.19 W/(m.K)
Aluminum 205 W/(m.K)
Magnesium Alloy 70-145 W/(m.K), where Watt=Joule/sec (hint).

https://www.engineeringtoolbox.com/t...ity-d_429.html

Shouldn't be too hard for a man of your caliber . . take a day to give it a try.

In the first place the complaint is condensation on the glass, bad pictures. If it would have been condensation just on the barrel it wouldn't have influence on the pictures.
In the second place a person holds his camera body in his right hand and the lens barrel in his left hand.
My post contained more as this.

George

[xpatUSA]

In the first place the complaint is condensation on the glass, bad pictures.

That was person A. Then, right away, here comes person B who has NEVER EVER experienced condensation on the glass. Not forgetting person C, who did get some ice under a lens filter and on an object lens.

If it would have been condensation just on the barrel it wouldn't have influence on the pictures.

Obviously, but what was your point?

In the second place a person holds his camera body in his right hand and the lens barrel in his left hand.
My post contained more as this.

George

My post made no reference to a camera body, so this comment is a Red Herring, sorry.

[NorthernFocus]

There wasn't a discussion of what might have caused this. That's the air getting colder...

Of course it is cooling of the warm air inside the lens that causes the fogging, George. No one disputes that fact. We've been discussing why some (few) lenses fog while most don't under same/similar conditions.

... And that happens first on places with the less heat resistance: your glass...

Not sure is something is being lost in translation but this isn't exactly true. Condensation will occur on the first surface to get cold. If the glass transfers heat five times as fast as plastic but the lens is six times as thick, then the plastic will cool first.

I don't believe in the barrel thoughts of Dan. Thin plastic is more for cheaper kit lenses...

Not any more. The vast majority of lenses, including many pro models, now have plastic barrels. Also many of the plastics used are composites filled with glass or carbon fiber for strength. So the heat transfer coefficient of glass is likely more on the order of 2x rather than 5x that of the plastics used in modern lenses. With some of these modern plastics it is very difficult to determine by appearance and/or feel whether that it is not powder coated metal.

But for Sandy's fogging lens, due to geometry or whatever it does indeed seem that the front element is likely cooling faster than the rest of the lens. However getting the air under that element to exchange with outside air may not be so simple. Good news is that it is easy to try. As would simply leaving the lens cap on and putting a hand over it for the first couple of minutes after going outdoors so that the rest of the lens cools faster than the front element.

[george013]

Of course it is cooling of the warm air inside the lens that causes the fogging, George. No one disputes that fact. We've been discussing why some (few) lenses fog while most don't under same/similar conditions.


Not sure is something is being lost in translation but this isn't exactly true. Condensation will occur on the first surface to get cold. If the glass transfers heat five times as fast as plastic but the lens is six times as thick, then the plastic will cool first.



Not any more. The vast majority of lenses, including many pro models, now have plastic barrels. Also many of the plastics used are composites filled with glass or carbon fiber for strength. So the heat transfer coefficient of glass is likely more on the order of 2x rather than 5x that of the plastics used in modern lenses. With some of these modern plastics it is very difficult to determine by appearance and/or feel whether that it is not powder coated metal.

But for Sandy's fogging lens, due to geometry or whatever it does indeed seem that the front element is likely cooling faster than the rest of the lens. However getting the air under that element to exchange with outside air may not be so simple. Good news is that it is easy to try. As would simply leaving the lens cap on and putting a hand over it for the first couple of minutes after going outdoors so that the rest of the lens cools faster than the front element.

I just can agree what you write down now in this context. And with the solutions.

George

[dem]

In the first place the complaint is condensation on the glass, bad pictures. If it would have been condensation just on the barrel it wouldn't have influence on the pictures.

When one goes from hot to cold with a jar or a camera full of moist hot air (by the way I am not convinced it is the air inside the lens, it can be the air inside the camera), condensation will take place on the parts that cool down first. This would normally be metal parts that are partially exposed to cold air. My guess is that the condensation takes place not on the lens but somewhere further down the optical path - most likely on the pentamirror in the viewfinder as it is most exposed to cold.

It should be very easy to check this - just take a shot. If the image turns out to be foggy as seen in the viewfinder, then this is the lens. If the image is clear, then this is the camera problem.

Using a camera with a pentaprism rather than a pentamirror might be enough to slow down the heat exchange so nothing in the optical path steams up. I am not sure I would like any condensation to take place on the electronics inside the camera though.

[xpatUSA]

When one goes from hot to cold with a jar or a camera full of moist hot air (by the way I am not convinced it is the air inside the lens, it can be the air inside the camera)

Dem, is the air inside the lens body somehow different from the air inside the camera body, at initial conditions (in the house, warm)?

If so, what is the difference?

[Manfred M]

Dem - rather than discussing theory, this is a problem that I live with when I shoot outdoors for 3 or 4 months per year; mid-November through mid-March. Right now it is a "balmy" -18°C / 0°F outside and the house is running around 21°C / 70°F inside.

Getting "moist" air trapped inside a camera / lens assembly is a non-issue most of the time. With most lenses, there is a fair bit of pumping action / air exchange going on as the lens elements move forward and backwards in zooming and focusing, so cold, dry air is drawn into the camera body, especially the mirror chamber and through the lens itself. As the camera and lens have not cooled down, this pumping action replaces / flushes the air out of these parts of the gear and there is enough residual heat in the camera body to warm up the air that enters without any condensation occurring..

Taking a camera outside in the cold is not the issue. The issue is bringing a cold camera back into the relatively humid house after a few hours of cold weather shooting. That's when condensation can be a real issue. Leaving the gear in a closed camera bag overnight is one solution and if I need the camera in a hurry, packing it and the lenses in a plastic bag for a couple of hours are both workable solutions. If I have a long drive from the shooting site to my home, leaving the camera bag open in back seat of the car works too. The car is relatively warm and the air drawn in from the outside in freezing temperatures is quite dry. The only humidity in the car is from me transpiring, and frankly that is generally a non-issue with the high air exchange rate in a car. The camera is often warm enough to not have a condensation problem by the time I get home.

[NorthernFocus]

...Taking a camera outside in the cold is not the issue. The issue is bringing a cold camera back into the relatively humid house after a few hours of cold weather shooting. That's when condensation can be a real issue....

I totally agree with Manfred (as stated many posts back). As has been discussed the problem that Sands is having with fogging is rare. There is almost certainly condensation occurring inside many if not most cameras taken out to shoot in sub-freezing conditions. It has been an interesting discussion but for most of us is not an issue. The volume of any internal condensate is EXTREMELY small due to the tiny amount of humid air inside the camera/lens. On the other hand exernal condensation if the cold camera is brought straight into a warm house can thoroughly wet the equipment. And since it will wet the entire surface is more likely to cause damage than shooting in moderate rain(which I've done too many times).

[Manfred M]

I totally agree with Manfred (as stated many posts back). As has been discussed the problem that Sands is having with fogging is rare. There is almost certainly condensation occurring inside many if not most cameras taken out to shoot in sub-freezing conditions. It has been an interesting discussion but for most of us is not an issue. The volume of any internal condensate is EXTREMELY small due to the tiny amount of humid air inside the camera/lens. On the other hand exernal condensation if the cold camera is brought straight into a warm house can thoroughly wet the equipment. And since it will wet the entire surface is more likely to cause damage than shooting in moderate rain(which I've done too many times).

Funny how those of us that have had plenty of practice in shooting in those conditions seem to know less about the subject than those who haven't. Not to forget, both have a background in thermodynamics and heat transfer.

[xpatUSA]

Dem - rather than discussing theory, this is a problem that I live with when I shoot outdoors for 3 or 4 months per year; mid-November through mid-March. Right now it is a "balmy" -18°C / 0°F outside and the house is running around 21°C / 70°F inside.

Getting "moist" air trapped inside a camera / lens assembly is a non-issue most of the time. With most lenses, there is a fair bit of pumping action / air exchange going on as the lens elements move forward and backwards in zooming and focusing, so cold, dry air is drawn into the camera body, especially the mirror chamber and through the lens itself. As the camera and lens have not cooled down, this pumping action replaces / flushes the air out of these parts of the gear and there is enough residual heat in the camera body to warm up the air that enters without any condensation occurring.

Thanks for some real numbers to consider, Manfred, especially those for inside a residence.

Now I see that "moist" and "dry" are indicative of water content by weight (i.e. by mass). For example, your house is approx 0.006 g/g inside and outside can't be any more than 0.003 g/g at -18C, even at 100% RH (estimated, my chart stops at -10C).

Since we are long past my talk of hermetic sealing, even the act of setting down the lens or camera or both outside has to draw some air into the assembly, simply because of the change in specific volume v of the internal air, from 0.84 to about 0.72 m^3/kg in your case.

Interesting is that, here in the South, it's much worse going the "other way" in summer i.e. from inside to outside, about from 0.014 to 0.035 g/g! (again estimated, my chart stops at 0.033). That is of course the equivalent of outside to inside in Canadian winter - but with a bit more water content involved because domestic economy dictates 75F on my thermostat when it's 95F and 90+ %RH outside.

In other words, I am also agreeing with the current consensus in this thread. It is good to see that we cognoscenti can iterate toward agreement in the end, in spite of a few bumps on the way.

[Manfred M]

Ted - inside air temperature is not the only factor during the winters. Houses are not 100% air tight and even if they are, interior combustion (things like gas stoves, furnaces, water heaters, fireplaces, etc.) requires air makeup to replace the air (oxygen component of the air), so cold, dry air is drawn in from the outside, either naturally (through cracks or openings in the building) or through artificial means (Heat Recovery Ventilator - HRV). This cool dry air has low absolute humidity as it enters the building, but as it warms up, the ability to hold moisture increases. Nicely said, it gets very dry inside the houses in the winter if things are left to themselves, so we humidify the air to make things a bit more comfortable.

New houses tend to be well insulated with 2 x 6 stud construction being the minimum standard; while older ones were build with 2 x 4 studs. The gap between the studs is filled with insulation (usually glass fibre) with exterior weather wrap and interior vapour barrier to keep the insulation dry. The problem (just like with camera lenses) is that glass is not a stellar insulator. The standard house construction in this part of the world uses double glazing, i.e. two sheets of glass with an air gap between them. This results with an amazing insulating property of R2. If you go a bit crazy and install double glazed, low-emissivity coatings, argon filled windows, that takes one up to R5. An inch of Fibreglas gives an insulating value of R14. This means that too much humidity results in condensation on the windows, which tends to ruin paint and can rot the wood if one has wooden windows. This means indoor humidity has to match the outdoor cold conditions, so the interior of my house is running at about 30% relative humidity right now. That will drop to 20% - 25% as we get those cold -25C to -30C conditions in January and February.

In our summers, we have issues like you have in the south; relative humidity in the 90% plus range. Air conditioning or mechanical dehumidifiers keep the interiors down in the 60% range on relative humidity. With interior temperatures like you have 24C / 75F, we do very occasionally see a bit of fogging / condensation if we take our camera gear outside, especially if we do so right after a heavy downpour.

[xpatUSA]

Ted - inside air temperature is not the only factor during the winters.

"inside air temperature is not the only factor during the winters."

Yes, Manfred, I did know that!

" An inch of Fibreglas gives an insulating value of R14."

Is that Metric or U.S.?

U.S. is R/in = 3.1-3.4/inch:

https://www.greatdayimprovements.com...lue-chart.aspx

"With interior temperatures like you have 24C / 75F, we do very occasionally see a bit of fogging / condensation if we take our camera gear outside, especially if we do so right after a heavy downpour. "

My wife likes to crank the kitchen AC down to 66F while cooking; then goes off and leaves it thus, to get quickly back on FaceBook. First sign of that is condensation streaming down the outside of all those single-pane windows! After 32 years here, that still looks odd to me, an English-born gent who grew up with a gas stove in the kitchen and no A/C.

[NorthernFocus]

Similar to what Manfred described we typically experience inside RH in the 30-40 percent range here in south central AK. It was much drier in Fairbanks with the colder average outside temperatures. Many people there ran humidifiers in their homes. In those severe cold conditions(below -18C) moisture management in houses can be a big problem if they are not properly constructed. If buildings are too tight/inadequately ventilated inside RH can run on the opposite end of the spectrum and mold can become an issue. We rented a house for a few months that had been built in the late 70s during the oil boom. During that time several builders/developers moved up here from California and built houses to California energy conservation standards (i.e. focused on sealing them as tight as possible). We moved into the house in fall and when winter arrived the windows and interior walls were covered with condensation. After a few days of that I located an obscure switch in the crawl space that forced the furnace fan to run continuously which solved that problem. The rental agent had neglected to tell us about that little detail.

Bringing the discussion back to photography and to satisfy anyone's desire for quantifiable facts, I ran a quick calculation on how much moisture would condense inside the largest lens that I own, a 500mm prime. Please excuse my mixing standards of measurement but I am a Yank after all. The interior space of that lens is roughly 4in diameter x 15in long so 1.25 cu ft. Accounting for internal components lets call it an even one cu ft of air inside. At 68 degrees F(20C) and 40 percent RH, the water content in air is about .006 lb/lb(or g/g if you please) and specific volume is about 13.5 cu ft/lb. So initially we have .006/13.5=.00044lb(0.2g) = 0.2ml of water. If we go out to shoot in temperatures around 15F(-10C) then saturated air contains about .002 lb/lb(g/g) of water. So roughly 2/3 of the 0.2ml condenses. That's about 2-3 drops of water from a standard eye dropper. And that spread around as a thin layer of condensation.

I guess that explains why the lens isn't fitted with a drain on bottom

[george013]

The amount of air inside a camera is indeed very little.

About house constructions. The isolation in a hollow wall will also result in a higher surface temp in the inside. In Holland the walls aren't that thick. So with no or bad isolation the surface temp of the wall might get earlier below dew point and resulting in fungus. A problem in many apartments. People are closing all openings in the house to save energy. Resulting in less and less ventilation.

George

[xpatUSA]

About house constructions. The isolation in a hollow wall will also result in a higher surface temp in the inside. In Holland the walls aren't that thick. So with no or bad isolation the surface temp of the wall might get earlier below dew point and resulting in fungus. A problem in many apartments. People are closing all openings in the house to save energy. Resulting in less and less ventilation.

George

Interesting, George. Older English houses had 9" thick brick walls with about 1" plaster on the inside. About 25cm total. Then heating was often by coal-gas or natural gas heaters, e.g. Robinson-Wiley, standing alone in the fire-place - meaning that not all products of combustion went up the chimney.

Moving into an older property usually meant new wall-paper or re-painting.

[skitterbug]

I want to finish out this thread by letting everyone know that the refurbished EOS 7D Mark II arrived and seems in good working order. To look at it, one would never know it was refurbished. It is dated - 2014 - so it's been around somewhere? I also sprung for the EF 100mm F/2.8L Macro. I still have to make up my mind about what lens to use for birding, nature. Since Canon nicely included a coupon to use before January 15 (I think), I may need to made a decision fairly soon!

AND no, I haven't tried taking my Rebel or my Mark II out in this bitter cold to see what sort of condensation problem I may end up having! That will have to be an experiment for a bit warmer day. It is currently 5 degrees F and that's very cold for us so I'm staying inside!

Thank you for all of the interesting and helpful posts! And here's hoping we have a Very Happy New Year of 2018!