Shooting in humid environments

[johnmc]

Hi everyone,

I'm venturing into the Melbourne Zoo tomorrow with the family and (as per every time I go) I'll be taking way too many pics - at least it's too many in my family's opinion

I'm keen to try out the macro gear in the butterfly house, but seem to remember lenses fogging up in there on previous occasions (admittedly with a P&S rather than DSLR) - are there any tricks to avoiding this? (I'm hoping something as simple as a UV filter will help)

Thanks in advance

John

[Matt. K]

Before entering the enclosure place the camera into a ziplock plastic bag and seal it up. Enter humid enclosure and wait until condensation no longer forms on outside of ziplock bag. PS...I have never tried this but I do remember reading it somewhere many years ago.

[Big Red]

place camera in a plastic bag and suck the air out of it.
[camera comes up to temp quicker than with air around it]
enter humid zone and wait for camera to stabilise temperate before removing from bag.
any water that forms will be on the plastic bag and not on the camera.

[johnmc]

ok... plastic bag here we come

Thanks guys.

[DaveB]

So how did it go? How long did it take to warm up?
Was the family ready to move on before the camera was ready to shoot?

[johnmc]

The bag worked a treat! And of all the shots I took on Sunday the butterfly house ones seemed to be the better. I shot with my Sigma 70-300mm all day - and whilst it provided me with some good tight shots, most of the shots were VERY underexposed - I was shooting in Tv mode as I wanted to avoid too much camera shake (of course once I remembered to increase the ISO it made a difference - but many shots were still underexposed), but an overcast day with not great lighting didn't help. For whatever reason the previews seen on the cameras LCD looked quite good - but once transferred to a PC they looked shocking! I'm going to see how much I can recover from them (one advantage of shooting in RAW mode I guess), but I'm not holding my breath.

a few samples below:

[DaveB]

I shot with my Sigma 70-300mm all day

Hmmm.... I notice in your sig that you describe this as a 70-300mm/1.4-5.6 lens. Wow, f/1.4 @ 70mm? Or did you mean f/4.5-5.6?

most of the shots were VERY underexposed - I was shooting in Tv mode as I wanted to avoid too much camera shake (of course once I remembered to increase the ISO it made a difference - but many shots were still underexposed)

Was it that the lens was going wide-open but there still wasn't enough light?
Don't be afraid to raise the ISO. Keep in mind that (as an example) a well-exposed image at ISO 400 will be less noisy than an ISO 200 image underexposed by one stop (even on your 10D).

For whatever reason the previews seen on the cameras LCD looked quite good - but once transferred to a PC they looked shocking!

This is quite normal for many cameras. The image you see on the LCD is not trustworthy in terms of judging exposure (especially outdoors). You should have the camera displaying the histogram as well, which gives you concrete feedback about the exposures.

[johnmc]

Hmmm.... I notice in your sig that you describe this as a 70-300mm/1.4-5.6 lens. Wow, f/1.4 @ 70mm? Or did you mean f/4.5-5.6?

oops my Sony (fixed now)... the detail on the lens actually reads 1:4-5.6 (note the colon, not the period) - the lens can be seen here: http://www.shutterbug.net/equipmentreviews/lenses/0500sb_sigma/ (the DL version)

Was it that the lens was going wide-open but there still wasn't enough light?
Don't be afraid to raise the ISO. Keep in mind that (as an example) a well-exposed image at ISO 400 will be less noisy than an ISO 200 image underexposed by one stop (even on your 10D).

Yeah I think it was simply just a lack of available light - even some shot with: 1/125s at f/4.5 ISO 400 - yes I eventually remembered to up the ISO - are surprisingly dark - as an example: http://john.mcclumpha.org/photos/CRW_0730_sml.jpg - sure that was at f/5.6 - although this was definately dependant upon the time/place - compare http://john.mcclumpha.org/photos/CRW_0855_sml.jpg - shot with: 1/125s f/5.6 ISO 200

I think with the lack of available light I should really have taken the tripod in with me (yep - it was in the car!) - but you live and learn.

You should have the camera displaying the histogram as well, which gives you concrete feedback about the exposures.

Good idea... I'd completely forgotten about that functionality (I used to use a 10D where I worked previously, but it's been a while)

Thanks for the feedback/advice - fingers crossed for some better shots next visit (although I think Werribee zoo is on the cards next).