Filters....response from T&T

[JeffAustin]

Any filter that decreases the amount of light hitting the film will only make catching a great shot more difficult because you will have to compensate for the filter by opening up your lens(less depth of field), using a slower shutter speed(more chance of blur) or boosting your sensitivity(more grain or noise).

Remember, you loose approximately 1 F stop for every three feet of depth (and that is in semi clear water). That is enough of a challenge when trying to do available light shots, no need to make it harder with a filter.

 

[James connell]

JeffAustin once bubbled...

Remember, you loose approximately 1 F stop for every three feet of depth (and that is in semi clear water). That is enough of a challenge when trying to do available light shots, no need to make it harder with a filter.

this is one of the stupidist things i've read yet! 1 stop for 3 ft!!??!!
so you're saying that in reasonably clear water at 33 ft down on a sunny day i'd get 1000 times less light?

let's see - sunny 16 rule shooting 100iso film =125th @ f16.
33 ft down = 15th @ f 1.4. HA! BS.

more like 125th @ f4or f5.6 (maybe even f8 @ noon). that's about 3 stops.
come on - how many people ever shot mollassas reef, key largo?
what was the settings?
you don't lose that much more light down to 100 ft ( ~2 stops)

if you don't know how to Use filters don't use them butjsut because YOU can't don't tell others they can't.

take a look at the green posts that were photoshoped - with a filter it is possible to get very close to the good PSed one on a slide. around montery cal, the water is quite green, you can filter that green out and leave "tropical" looking backgrounds with a M15CC ( lose about 1 stop). at point lobos (on a fair vis day) with iso400 film you can easily shoot 125 @ is fine.

the pix that were psoted look very much like the colors you get in puget sound. those can be cleaned up ( not perfectly however) with a M30CC.

if i can get them of a bad HD i'll post one from 60 ft down in the south sound in 10ft vis. looks like the tropics (except for the forshortened background). exposure was 30th @ f4 with a 28mm and a M30CC filter.

 

[TheAvatar]

JeffAustin once bubbled...
Any filter that decreases the amount of light hitting the film will only make catching a great shot more difficult because you will have to compensate for the filter by opening up your lens(less depth of field), using a slower shutter speed(more chance of blur) or boosting your sensitivity(more grain or noise).

This subject has been beat to death already in the other post. I don't see why it warrants a new post. But... whatever...

Remember, you loose approximately 1 F stop for every three feet of depth (and that is in semi clear water). That is enough of a challenge when trying to do available light shots, no need to make it harder with a filter.

Perhaps you are referring specifically to 600nm and longer waves (Red)? Maybe that rate would hold somewhat true... Otherwise, you are full of it. James is quite right in pointing out the obvious flaw in your statement using simple math to prove how ludicrous a claim this is.

 

[Dee]

JeffAustin posted this response to blacknets tip in the Tip & Technique thread. Since we've asked that any discussions be continued here, I split his post into a thread of it's own. So it's a possibility he isn't even aware of it and had no intention of starting this subject again.

 

[TheAvatar]

Thanks Dee for clearing that up. Now that I read waht blacknet said, I can say I agree with him. There is not much purpose for filters underwater. If James finds them usefull, more power to him. Nobody said he should stop.