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-   -   avoid heavy reflecting sunlight (http://www.oople.com/forums/showthread.php?t=4106)

Cooper 15-06-2007 10:14 AM

avoid heavy reflecting sunlight
 
how can I avoid heavy sunlight reflections in my photo's ?
those shiny fluoyellow wheels can sometimes screw things up..

http://www.rc-offroad.be/pictures/20...s/bnk6_001.jpg

JCJC 15-06-2007 11:06 AM

Possibly use a Polarising filter, I think these are used to filter reflected light off water, sometimes used to "blue" up the sky.

I was wondering about using flash - can see it causing problems with drivers on the rostrom but may produce some interesting pictures ?

janus_77 15-06-2007 01:31 PM

simple, dont take pictures of shiny cars :rolleyes:

jimmy 15-06-2007 01:49 PM

True, a polarising filter might help a little, cutting down on some glare. I used a polariser for the first time in anger (though I've had it for ages) last weekend.

It can cut out a lot of the glare on the cars - whether thats a good thing or not is another matter as it can make the cars look a little unreal almost.
http://www.oople.com/rc/photos/buryn...s/OOP_8813.jpg


I think the main problem is one of simple metering though - you are using some sort of automatic metering and the dark trees in the background are fooling your camera into thinking the scene is a dark one- and thus compensating by overexposing. I first found that at the Euros 2005 - the only way to get good photos with the dark wooded area in the background was to use the camera in full manual mode to stop the overexposure.. You can probably probably adjust the exposure compensation but I find it easier to just go fully manual.
I find shooting at tracks like Southport and even Lee Martins CML track to be quite difficult since the racing surface is black in areas, or at least was at southport. It would always overexpose and wash out the colours... combined with the fact that the trees had partial cover over the track made it a nightmare.

JCJC 15-06-2007 03:19 PM

The problem with fast cars is you have to be quick, getting back into using the camera now after 20 years, but can remember using a filter and being able to rotate the filter to adjust the amount glare tacen out, stand there for minutes trying to make an adjustment.

What chance of doing this in software once shots are on the 'puter, and what chance to use something like a star filter to enhance the glare !!

I know its Friday afternoon and I am drifting............:) :p :rolleyes: ;)

racing sunday, will have a play if no breakages..........Mick

mole2k 15-06-2007 07:03 PM

circular polariser filters are great, I use them quite a lot although you really need a lens with USM focusing so you dont get a rotating end element otherwise you will get varying amounts of polarisationg in your shots.

Halcalanky 06-07-2007 12:35 AM

Very delayed reply, but there you go :P

Skylight filters also make a small difference. The issue with polarisers is they knock off a stop or 2 of light - slower shutter- but if the suns bright enough to give you glare, you might be able to get away with it. Skylights are like £5 with decent polarisers £35 - always use a skylight and and protect your nice filter or lens! Skylights don't lose you any light too.

You can meter a upto a stop underexposed and then use levels on the photo editing program to fix it. You can correct underexposure but NOT over exposure.

P_B 11-07-2007 10:03 AM

Quote:

Originally Posted by Halcalanky (Post 48377)
always use a skylight and and protect your nice filter or lens! Skylights don't lose you any light too.

Then there's the flipside of the argument - why buy well designed optical-grade glass with low dispersion elements and special multicoatings, only to then go and screw a cheap piece of flat glass on the front?

I only say this after I recently dropped a lens :( Whilst the UV filter took the brunt of the impact and broke it didn't save the lens and I had to make an insurance claim - who ironically refuse to pay for a replacement filter!

When the repaired/replaced lens comes I won't be bothering with a UV and the increased risk of ghosting and flare and also the reduced contrast it can bring.

As for Coopers' original question, Jimmy has provided the correct explanation. Those dark trees are fooling the camera into raising the exposure, which then has insufficient dynamic range to capture the really bright areas properly. A polariser might help an otherwise 'normal' scene with some bright glare, but not really with large shadow areas.

If you don't fancy going full manual and your camera has different metering modes, how about trying centre-weighted or even spot metering rather than matrix/evaluative? This will bias the camera's exposure judgement towards the subject in frame rather than conditions on the periphery.

Halcalanky 11-07-2007 03:41 PM

Quote:

Originally Posted by P_B (Post 49318)
Then there's the flipside of the argument - why buy well designed optical-grade glass with low dispersion elements and special multicoatings, only to then go and screw a cheap piece of flat glass on the front?

I only say this after I recently dropped a lens :( Whilst the UV filter took the brunt of the impact and broke it didn't save the lens and I had to make an insurance claim - who ironically refuse to pay for a replacement filter!

When the repaired/replaced lens comes I won't be bothering with a UV and the increased risk of ghosting and flare and also the reduced contrast it can bring.

I use mine to protect from scratches if I'm out and about mostly, not for saving it if I drop it ;)

I use a Hoya skylight, I picked it up for only a fiver. Hoya filters are awesome, I wouldn't use anything less. I've used some cheaper ones, and found they don't ghost or flare - just a very slight drop in contrast. With the Hoya theres minimal change when I was shooting Raw - I'd rather trade a tiny bit of touchup in photoshop for the sake of saving scratching a lens.

mole2k 11-07-2007 04:21 PM

I shoot a lot of rallys so I use the uv filter to protect the camera from flying stones, also front element would get caked with dust and other grim and require to be cleaned regularily. As im shooting with L spec glass and using Hoya filters the difference is minimal. I do remove mine when shooting in situations were glare will be a problem though such as fireworks or other such painting with light exercises.

Also since im shooting raw I have no problems with lack of contrast, if it just means i +1 on the contrast or shadows slider then so be it.

P_B 11-07-2007 05:27 PM

@Hal & mole - Exactly the answers I wanted to read, good stuff :)

Just playing devil's advocate and generating discussion so people get both sides and don't take one or two posts as gospel ;) Stands to reason that you should protect any lens from risk of flying debris and not with cheap nasty filters either. That's a given. My UV was a Hoya even though it was only attached to a budget zoom. However, I'd say that in more 'general' use a lens hood does as much for avoiding scratches as a UV but without the associated drawbacks.

Dust is a different matter, a few specks on the lens have little or no effect and optical grade glass is pretty damned tough so can withstand a lot of cleaning - whether the coatings can or not though is a different story...

And of course, not much will save a lens if you drop it :(

I agree that sensible use of a quality UV filter is a very good idea but it's not a 'fit and forget' item - I'll be using one for racing pics and dusty conditions, but also leaving it off a good deal of the time.

@Cooper - sorry if I've dragged this too far off-topic!

mole2k 11-07-2007 08:56 PM

1 Attachment(s)
Generally I find anytime I have lights shining at the camera I remove the UV filter to stop any chances of ghosting, although the only time i've really experienced ghosting badly was when shooting fireworks last year after 2-3 shots I removed the UV filter as i was getting green ghosting appearing as a reflection of the image.

As mentioned previously too little contrast has never been a problem I've had!


Getting back on topic I use center weighted metering for most stuff anytime there is difficult lighting conditions i either dial in a bit of +/-EV, the more sun the more EV I find I often need to dial in some negative. At the weekend I was doing some shooting at a rally and when the sun came out strong I was using up to -1 EV but when it went away I returned to my usual +1/3.

Halcalanky 11-07-2007 11:18 PM

That's an awesome picture :D I always tend to underexpose by 1/3 on shots - I'm using a 300D so the metering isn't perfect :P I'm using an EF-S lens that uses L glass, but can't be qualified as L as it's EF-S, not EF (silly canon!)

I've never experienced any ghosting :/ Only trouble I've had is dust on the sensor.. turns out changing lenses near sand at an air show isn't smart ;) managed to clean it off ok tho! I just had to do some touch up work to it afterwards.

More back on topic: If you are using a polariser, if the end barrel of your lens doesn't rotate, you don't need to re-adjust. I forgot to re-adjust when using a zoom lens, had it on manual and then ended up with a lot of very poorly exposed photos.

mole2k 12-07-2007 01:11 AM

Yeah that was one thing that turned me off using polarisers untill I got myself some lenses that didnt rotate while focusing.


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