New Equipment

[xpatUSA]

I believe I did provide credible references with the hot and cold tea.

Dan, you provided no references whatsoever. Sayin' it don't make it so.

But you brought up a valid point that including the tea may have complicated the matter. So for anyone desiring the test the theory simply do the following on a cold winter's day. Simply take an empty glass out of the cupboard in your nice warm house and straight away walk out into the sub-freezing outdoors. Does condensation form on it? No. So why would it do so on a camera? Now leave the glass outside(in a dry place) until it reaches outside temperature. Preferably put a kettle on and have a cup or two of your favorite hot beverage while you wait. Now go grab the glass and bring it back into the toasty warm house straight away. Does it sweat? Then why wouldn't your camera.

It is tempting. But I'm 93 days into recovery from ARS and not willing to give that up for this particular topic.

But you did fail to account for DP in your closed system(and fixed volume) analysis

This is getting silly, sorry.

If only I knew what "DP" was or even "ARS" for that matter, I could respond sensibly.

I fold. Our discussion is over. The coveted Last Word goes to you.

Perhaps George will be along to help you shortly . . .

[NorthernFocus]

...Sayin' it don't make it so.

But Seein' it does for some folks.

If only I knew what "DP" was or even "ARS" for that matter, I could respond sensibly...

Sorry,DP; aka dP or delta P; As you well know in a closed, gas filled system of fixed physical volume if T changes then so must P. Relative humidity is dependent on both. If pressure remains constant as in your analysis then the system isn't closed in which case the assumption of a fixed mass of water is not accurate. Pick one or the other. Also maybe consider the effects of dynamics and not just the end state. If you're going to do the ANALysis then do it completely.

ARS= anal retentive syndrome. Unfortunately I fear this thread has knocked me back to day zero

[xpatUSA]

If pressure remains constant as in your analysis then the system isn't closed in which case the assumption of a fixed mass of water is not accurate. Pick one or the other.

In my last analysis, which you appear not to have read, I said:

"Air inside the system (camera+lens) starts at 20 deg C and 0.01 kg/kg water content. It is taken outside; as the temperature inside falls, condensation starts at 14 deg C. At about 0 deg C, the condensate freezes and continues to accumulate. Let's continue down to -5 deg C. At this point, the water content of the internal air is 0.0025 kg/kg meaning that 75% of the origin water content is now ice on the inside of the system. Now say that the ice sublimates somehow while the internal temperature remains at -5 deg C."

Please point out to us all where I said that "pressure remains constant" . . .

Also maybe consider the effects of dynamics and not just the end state. If you're going to do the ANALysis then do it completely.

I resent the implication of the capitalized "ANAL" and the generally provocative nature of that line.

This is for sure my last correspondence with you on this subject Dan.

[billtils]

Guys, 'tis the season of goodwill! I don't know what the photography BB equivalent of "kiss and make up" is, but you are two of my absolute favourite contributors here and I'd be sad to see this end up by making one or both step back from your participation in CIC discussions.

[rpcrowe]

My very worst problem with condensation was not due to extremely cold ambient temperature. I planned to shoot a butterfly exhibit at the San Diego Zoo Safari Park (AKA: Wild Animal Park) using a Canon 7D camera with a 90mm Tamron Macro lens.

The exhibit was approximately a quarter of half mile from the entrance to the park. I walked there with my camera/lens hanging from a strap. The temperature was about 45 degrees F. (~7 degrees C) at a relatively low humidity. The temperature in the exhibit area was over 85 F (~29 C.). The lens immediately clouded with moisture and since the front element of the Tamron is deeply recessed I had a hard time wiping off the fog.

On my next visit to the butterfly exhibit, I carried my camera/lens on a strap but, this time beneath my coat. Since there was not a great difference in temperature between my camera/lens and the ambient temperature, I had no problems with fog.

[NorthernFocus]

...Please point out to us all where I said that "pressure remains constant" . . .

Constant pressure is implied in the numbers used for water content which correspond with values at standard atmospheric pressure at the various temperatures given.

[NorthernFocus]

Guys, 'tis the season of goodwill! I don't know what the photography BB equivalent of "kiss and make up" is, but you are two of my absolute favourite contributors here and I'd be sad to see this end up by making one or both step back from your participation in CIC discussions.

Certainly I apologize, Bill. Both to Ted and the community at large. I'd intended to use a bit of self-deprecating humor to make a point. I should certainly have stopped when the first attempt failed. But truly, how does a thread go from someone asking for some simple advice on purchasing equipment morph into discussion of mollier diagrams etc? Really?

[NorthernFocus]

My very worst problem with condensation was not due to extremely cold ambient temperature. I planned to shoot a butterfly exhibit at the San Diego Zoo Safari Park (AKA: Wild Animal Park) using a Canon 7D camera with a 90mm Tamron Macro lens.

The exhibit was approximately a quarter of half mile from the entrance to the park. I walked there with my camera/lens hanging from a strap. The temperature was about 45 degrees F. (~7 degrees C) at a relatively low humidity. The temperature in the exhibit area was over 85 F (~29 C.). The lens immediately clouded with moisture and since the front element of the Tamron is deeply recessed I had a hard time wiping off the fog.

On my next visit to the butterfly exhibit, I carried my camera/lens on a strap but, this time beneath my coat. Since there was not a great difference in temperature between my camera/lens and the ambient temperature, I had no problems with fog.

Great example, Richard.

Another issue often encountered when shooting in the cold with relatively short lenses is the moisture in one's breath fogging the lens. Since the camera is pointed away from us when shooting many people don't recognize the possibility of this occurring. When we exhale our breath is expelled under the camera/lens. Since warmer air rises then our breath creates a pocket of warmer/wetter air around the camera which then condenses and/or freezes on the lens. When it does freeze it's a pain to remove other than waiting for sublimation to naturally clear it as Manfred pointed out earlier. I've also had this happen to me with a 500mm lens mounted on a tripod carried over the shoulder. Lesson learned. When carrying it make sure the lens is pointed behind you

[skitterbug]

Hi Everyone! I wanted to let the group know that I've put information on a spread sheet, all suggestions, models, lens choices, etc. Talk about confusing! And yes, prices are all over the place! There are rebates happening at Canon, refurbished gear that seems appealing, etc. It still looks like Canon is the brand I'll choose, and probably cropped sensor (APS-C) however some of the FF ones seems interesting too. (I dislike making decisions.)

Also through all of the discussion, I'm thankful about the information about haze/moisture and that it isn't "just me" having that issue. I always thought it was my camera gear not being sealed properly. Now at least I know that isn't the reason. So hopefully the "heated discussions" result in ideas shared rather than broken "friendships".

If anyone would want to put a kit together (on paper of course) and post it, I'd really appreciate the ideas shared.

Enjoy the day! Time to take photos!

[george013]

Certainly I apologize, Bill. Both to Ted and the community at large. I'd intended to use a bit of self-deprecating humor to make a point. I should certainly have stopped when the first attempt failed. But truly, how does a thread go from someone asking for some simple advice on purchasing equipment morph into discussion of mollier diagrams etc? Really?

May I remind you that one of the reasons for new gear was moist.
May I also make clear that the Molier diagram was only meant to show the dependency between humidity and temperature. I don't give a damn if condensation happens at 7C or 7.1C, or if humidity is also depending on atmospheric pressure.

George

[AlwaysOnAuto]

Sandy - Since you admit to being 'aged' I suggest you look at my post #14 again.
If possible, get to a store and handle a Sony A7Rii.
With my A7ii, I not only get the choices of many kinds of lenses via adapters, I also get image stabilization with any manual focus lens mounted as well as all the virtues of a FF camera.

[NorthernFocus]

That's interesting. I would be interested in seeing comparisons. You certainly lose pixels by cropping like that:

7DII, entire frame: 19.96 MP
7D I, entire frame: 17.92 MP
5DIII cropped to APS-C sensor dimensions: 8.64 MP.

This loss of detail won't generally be apparent online unless one crops severely because of the low resolution of computer monitors. Printing is another matter. And there may be other attributes of the particular FF in question that offset this consideration anyway, e.g., in my case (7DI and 5DIII), low-light characteristics.

I don't do many birds, but I almost always use the crop because I know I will often have to crop substantially in postprocessing, even with my longest (400mm) lens.

BTW, when I got my 100-400, I did an A/B comparison to see the effect of increasing the reach of the 5DIII by using a Canon 1.4X II teleconverter. Condition 1 was 5DIII, the lens at 400mm, and the teleconverter. Condition 2 was the 7D with the 100-400 set at 350 mm, which is the same angle of view. No contest: the second was much sharper. I assume the main issue was the 1.4 x teleconverter, not the focal length setting of the lens.

But in any case, this isn't much data, so if you have a few image pairs that illustrate your point, I'd be eager to see them. It might change what I do, since I have both options.

Dan, I think the basis for the often heard recommendation regarding cropping FF versus shooting APS-C for wildlife is an issue of "pixel quality". Since wildlife is often shot in marginal lighting and (overall)FF sensors tend to perform better in low light IQ may actually be better even with lower pixel count. Or at least that's the argument. And to some degree that's been my experience. When on a serious shoot I typically carry both my D810 and D7200. In good light the unfiltered 24MP D7200 sensor produces amazing IQ. But when lighting drops off I find that I'm better off shooting the D810 in 1.5x crop mode which yields 15MP images but cleaner.

But of course general rules always break down at some point. Even in low light a current generation high pixel count APS-C sensor may very well perform better than an older FF sensor.

Sorry I don't have any direct comparison images to post for reference. Just relating personal experience gained over time. Where I do most of my shooting poor light is the norm.

[DanK]

Thanks. That’s helpful


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[skitterbug]

Sandy - Since you admit to being 'aged' I suggest you look at my post #14 again.
If possible, get to a store and handle a Sony A7Rii.
With my A7ii, I not only get the choices of many kinds of lenses via adapters, I also get image stabilization with any manual focus lens mounted as well as all the virtues of a FF camera.

Hi Alan - I was disappointed - way back when - that I couldn't get my first digital Sony repaired and so I haven't considered them seriously since then. I should get to a store (not an easy task since there isn't a camera store in my immediate area) and get some 'hands on experience' if I can. What looks good on the web may actually be clumsy in my hands. I'd love to take advantage of the Christmas sales that are currently going on but if it doesn't happen now, it will eventually. Hopefully, there will be more "sales" due to new models replacing older stuff. I don't need newest and best, just decent and affordable! <grin>

Thanks for your suggestions!

[Dave Humphries]

I like this exercise Dan, although it doesn't cover all the practical issues in play

~ So for anyone desiring the test the theory simply do the following on a cold winter's day.

Simply take an empty glass out of the cupboard in your nice warm house and straight away walk out into the sub-freezing outdoors.
Does condensation form on it?
No. So why would it do so on a camera?

Now leave the glass outside(in a dry place) until it reaches outside temperature. Preferably put a kettle on and have a cup or two of your favorite hot beverage while you wait.
Now go grab the glass and bring it back into the toasty warm house straight away.
Does it sweat? Then why wouldn't your camera.

Building on your example ...

Take a glass saucepan and lid out of the cupboard in your nice warm house and fit lid, then straight away walk out into the sub-freezing outdoors.
Does condensation form on the outside of the glass saucepan? No.
Does condensation soon form on the inside of the glass saucepan? I suspect it will.
(it still has warm air in there, in intimate contact with the rapidly cooling glass walls - much like the inside of a lens barrel, front/rear elements and the insides of camera)

Now leave the glass saucepan (with lid on) outside (in a dry place) until it reaches outside temperature.
~ optional beverage break ~
Now go grab the glass saucepan (with lid on) and bring it back into the toasty warm house straight away.
Does it sweat?
On the outside: Yes
On the inside: I suspect not.

Of course, I haven't actually tried this experiment, it is (thankfully) rarely cold enough here to do it where I live.

[Rufus]

I hesitate to post in such knowledgeable company, not least because I was in a similar position a year or so ago and by the end of this post fellow contributors may conclude that I have more money than sense and competence combined! I am a mere hobbyist who takes landscapes, architecture, studio pics at my local camera club, and general travel and family shots.
I had a Canon 450D the kit lens EFS 18-55, EFS 10-22, EFS 55-250, EF 35 and EF 50.

The point is well made that the skill of the photographer is the most important contributor to a good image, but I was also in a position to change.
My priorities were a fully articulating screen for easier use on a tripod and at low levels, more focusing points, more sensitive DoF, better performance in low light, and more pixels to play with and possibly Full Frame. GPS was a “nice to have” to save checking my itinerary after the event.
I decided to wait for the Canon 6D Mk2 to be announced. It seemed to have everything I wanted (built-in flash and video capability were not at all important to me).

I knew I would not carry 2 cameras so I decided to trade in my 10 year old camera body and the EFS lenses rather than let them gather dust. Most of the value was in the wide angle zoom. I was surprised that the body had any value to be honest.

I bought the 6D2 body without a lens. To add to the fast 35mm & 50mm prime lenses I bought a fast 135mm prime. I also bought a 24-105 f4 as my walkabout lens.
I kept my Canon EX580 flash which I had bought second hand a few years back as it has been totally reliable despite the signs of significant use by the previous owner(s).
I am delighted with this setup. One day I would ideally like to add a Macro lens and a wider lens for landscapes. I don’t feel I need anything longer than 135mm.

I have blown your budget with this I’m afraid but these are probably the last investments I shall make in DSLR Photography. If these see me through another decade I shall be happy enough and I am sure they will last longer than that and still perform well.

This is not an evidence based post but it may be of some use as a possible solution.


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[skitterbug]

Hi Rufus - I think purchasing the camera body and then picking out lenses is the way to go. I was checking out EOS 7D Mark II without wifi on Canon's site. I like the idea that it has 2 digic 6 processors rather than 1 digic 7. Sounds like this has an advantage of faster processing if I understand what I'm reading.

I'm curious about a website called 42nd Street Photo that offers this same camera for $300 less than Canon or B&H Photo. It is also located in New York. Have you or anyone else ever done business with this company? And is this true Canon gear that will be covered by Canon warranty? I noticed on places like Amazon, they have International Camera equipment and they say there is no warranty offered with it. I definitely wouldn't want to deal with that.

Lenses are expensive! The two I have with my current kit are average I believe but they might still be useful. I rather doubt that there is much used value in the Rebel T3i so I'll keep it and maybe pass it along to my daughter if her hubby doesn't get her "something" for Christmas.

I appreciate the information you shared about your kit. It is helpful to me to know what others have.

I've been hashing this decision over with hubby and he said that if I go over my amount a bit, he wouldn't be fussed about it. <whew> I'm trying to be sensible about all of this and take a little time to decide but I have to say that seeing "sales" adds pressure whether I want to succumb or not!

Thanks for taking time to share info! I appreciate it and will add your info to my "spreadsheet". I've been comparing models and finally took some headache meds. <LOL>

Cheers!

ps: Rufus - I like the look and description of the camera you have chosen. It is FF but I noticed that B&H has it plus the lens you like (and mentioned by others) for a decent price too. Oh.... that headache of mine is growing.. Thanks again for the info!

[Manfred M]

I'm curious about a website called 42nd Street Photo that offers this same camera for $300 less than Canon or B&H Photo.

The question to ask is whether the camera being offered is a "grey market" camera or not. Grey market cameras are ones that are imported by someone other than the official importer in the country. If it is, it will not come with a Canon USA warranty and if anything goes wrong with it, you might have problems getting it fixed. I don't know how Canon USA works, but I do know that Nikon Canada will not touch a grey market camera for repairs, even when it is out of warranty. I have heard that the other major camera manufacturers have similar policies.

[skitterbug]

Hi Manfred - That's what I was concerned about. There isn't an easy way to know this and it may be best to stick with sites that are known "good" places to do business even if there is a bit extra in the cost!

I still have that headache - so many good choices out there..... decisions to make. It'd be nice if "Santa" knew exactly what I needed and put it under the Christmas Tree.

Thanks for replying to my questions! I appreciate it lots!

The question to ask is whether the camera being offered is a "grey market" camera or not. Grey market cameras are ones that are imported by someone other than the official importer in the country. If it is, it will not come with a Canon USA warranty and if anything goes wrong with it, you might have problems getting it fixed. I don't know how Canon USA works, but I do know that Nikon Canada will not touch a grey market camera for repairs, even when it is out of warranty. I have heard that the other major camera manufacturers have similar policies.

[xpatUSA]

I like this exercise Dan, although it doesn't cover all the practical issues in play

Building on your example ...

Take a glass saucepan and lid out of the cupboard in your nice warm house and fit lid, then straight away walk out into the sub-freezing outdoors.
Does condensation form on the outside of the glass saucepan? No.
Does condensation soon form on the inside of the glass saucepan? I suspect it will.
(it still has warm air in there, in intimate contact with the rapidly cooling glass walls - much like the inside of a lens barrel, front/rear elements and the insides of camera)

Agreed and, with condensation present, the relative humidity inside is 100%.

Now leave the glass saucepan (with lid on) outside (in a dry place) until it reaches outside temperature.
~ optional beverage break ~

In addition: if that were say, 5 deg C, then no evaporation takes place inside because the vapor pressure of the condensate (867 Pa) is less than the partial pressure of the water vapor in the air (872 Pa). (I've been doing some reading, after being corrected by Manfred earlier).

Now go grab the glass saucepan (with lid on) and bring it back into the toasty warm house straight away.
Does it sweat?
On the outside: Yes
On the inside: I suspect not.

I think not, too, . . . for a while until all the external sweat has evaporated, leaving the internal conditions perhaps different to when the saucepan departed the house . . .

Of course, I haven't actually tried this experiment, it is (thankfully) rarely cold enough here to do it where I live.

Certainly not here at the moment either. Roll on Summer . .