nd filters vs altering exposure post prod

[n8]

I've been thinking about getting a/some nd filters for those times when I just may need one, but with my understanding that the goal is to be able to maintain wider apertures and longer shutter speeds, how much difference would it make to use a filter rather then take the overexposure and correct it later?

[calexp]

ND filters might degrade a bit the quality, as all filters do - depenting on the filter quality, but with them you get more detail than overexposing and correcting later, since the picture will be exposed correctly.

[mwfanelli2]

I've been thinking about getting a/some nd filters for those times when I just may need one, but with my understanding that the goal is to be able to maintain wider apertures and longer shutter speeds, how much difference would it make to use a filter rather then take the overexposure and correct it later?

When you change the exposure, you are often blowing highlights or shadows. You can't get something for nothing! An ND filter, high quality, cuts down the light entering the camera allowing a good exposure using the full DR of the sensor. No comparison, ND wins hands down.

[Greg McCary]

Maybe I am old school but I think getting as much right in the field as one can is the best solution. There is nothing like seeing it on the screen and knowing I nailed it without relying on after the fact processing. I vote for the filter. I have been using a Cokin ND system for a couple of years now and couldn't imagine not using it.

[OldClicker]

Maybe I am old school but I think getting as much right in the field as one can is the best solution. There is nothing like seeing it on the screen and knowing I nailed it without relying on after the fact processing. I vote for the filter. I have been using a Cokin ND system for a couple of years now and couldn't imagine not using it.

I was just reading an article about guys like you. The article was saying that camera makers still do treat digital like film when it comes to exposure. The better way would be to 'expose to the right' automatically (assuming you have the room at the right with the best ISO) and forget how it looks on the LCD (or compensate with the LCD jpg just for viewing).

But if you are in a situation that calls for an ND filter, you are probably beyond the range of the sensor and blowing out the highlights.

TF

[Greg McCary]

I was just reading an article about guys like you. The article was saying that camera makers still do treat digital like film when it comes to exposure. The better way would be to 'expose to the right' automatically (assuming you have the room at the right with the best ISO) and forget how it looks on the LCD (or compensate with the LCD jpg just for viewing).

But if you are in a situation that calls for an ND filter, you are probably beyond the range of the sensor and blowing out the highlights.

TF

I guess I have just shot so long with the E3 I can tell when I have it right. The highlights will blink on the LCD if they are blown out. You are right that what I have on the LCD will be different at home. But it will be close enough to adjust. I have tried HDR's and also combing exposures. But those techniques are flaky and hit or miss with me. I would hate to get home and see that I messed up so I try to get it right while I can. Going back can be hard to do sometimes. I bracket my shots in the field and I try different exposures at different ISO's. If I have a tripod I always shoot as low as I can go. Why not if I am already mounted up. If I try HDR's I will still use the filter and try it both ways.

[n8]

I would certainly rather do things the right way. I'm trying to decide on whether to buck up for a (couple) filters. I'm surprised to see that a set of 3 can be had for $50, while one can set me back over $100.

[mjs1973]

But if you are in a situation that calls for an ND filter, you are probably beyond the range of the sensor and blowing out the highlights.
TF

This comment and some of the things Greg is talking about make me think that we may be talking about 2 different things. From reading the original post, I was under the impression that the question was in regards to 'solid' ND filters. A filter that would darken the scene evenly across the entire frame allowing for the use of a slower shutter speed. This type of filter would have no affect on the dynamic range of the sensor.

The comment above and Greg's comments about HDR and combining exposures make me think some are talking about split or graduated ND filters.

These are 2 different tools for 2 different jobs, and would make me respond very differently based on what is being asked for.

If we are talking about a solid ND filter, I would say get a good filter and get it right in the camera. If you over expose your image because you want a longer shutter speed, you are going to blow out a lot of your scene. Once it's gone, it's gone. Even if you don't blow it out and are able to get it back, your image quality is going to suffer compared to capturing it correctly in the camera.

If we are talking about a split ND filter, I would suggest bracketing your shots and combine the photos in post to get your final result. From my experience, I can get a much better final image by combining multiple exposures than I can with a graduated ND filter. I can mask in the areas to blend the images together more naturally than I would get with a split ND filter.

[Frog]

. The better way would be to 'expose to the right' automatically (assuming you have the room at the right with the best ISO) and forget how it looks on the LCD (or compensate with the LCD jpg just for viewing).TF

I've been reading this thread. What does 'expose to the right' mean? I'm guessing it means to underexpose.

[Frog]

I would certainly rather do things the right way. I'm trying to decide on whether to buck up for a (couple) filters. I'm surprised to see that a set of 3 can be had for $50, while one can set me back over $100.

Get the best one you can afford. Using the cokin system will allow you to use the filter on any lens with their adapter rings. I've learned here, though it should be obvious, that putting cheap glass in front of your lens is certainly not going to improve the image.

[Frog]

[QUOTE=mjs1973 If we are talking about a split ND filter, I would suggest bracketing your shots and combine the photos in post to get your final result. From my experience, I can get a much better final image by combining multiple exposures than I can with a graduated ND filter. I can mask in the areas to blend the images together more naturally than I would get with a split ND filter.[/QUOTE]

I'd assumed split all along but you are right that it was never made clear.
Bracketing and combining images does make sense as you can get the correct exposure for the whole scene. The split nd can't actually do this as there will be overlap unless you have a perfectly level horizon.
I'm thinking the nd filter would be best for images with moving subjects, though.

This is mostly just thinking out loud, so to speak.

[readingr]

With my SLR's I have never found that I need a ND filter with Digital, with Film I used to use them a lot.

ND Grad's I have a set which have never been used with Digital. I tend to use the process offered up by Michael and expose for sky, then land/sea/whatever and then blend in PP'ing.

I am this year going to test the ND Grad's out and I'll post my findings, probably in the spring.

Roger R.

[OldClicker]

I've been reading this thread. What does 'expose to the right' mean? I'm guessing it means to underexpose.

Actually, film uses would call it overexposure. It has to do with the way we (or film) see light as opposed to the way our digital sensor sees it. The sensor is linear – it sees the same amount of difference whether it is in a dark area or in a bright area. If one spot has twice as much light, it records twice the value. For us the brighter it gets, the more (magnitudes more) difference there needs to be in the actual amount of light for us to see the difference. Here is probably a much more clear explanation than I would give you:

http://www.luminous-landscape.com/tu...se-right.shtml

Remember that you do NOT want to move the histogram to the right by increasing ISO in the range where it will just cause more noise anyway. From my understanding, with most DSLs, the break even point is ISO 800-1600.

TF

[freygr]

To get the nice smooth water with film or digital you need a long exposure time. With view camera most lens/shutters have apertures as high as F68 some higher! So getting a nice long exposure is not a problem, but most digital PS and DSLR's are limited as the F stops max out between F16-F32, with ISO's mostly starting about 200 which limits the long exposures. ND filters reduce the light so you can take longer exposures and get the correct exposure. But you also need a good tripod.

[Greg McCary]

Don't misunderstand me. I am not saying there is a right way or a wrong way to do things. Everyone does things differently and that is part of what defines their style. I have combined exposures and also used HDR's when shooting in buildings when a filter would have been useless. I think a photographer should use every means necessary to get the results they are after.