Neutral density filter question (Page 2): Totally agree. Graduated ND's are a worthwhile tool...if used properly.

Cdouthitt Loc: Traverse City, MI

martinfisherphoto wrote:

Holy Smokes, Grad filters Work. So what if you spend $80 bucks for a filter, it will last a life time and come in handy plenty of times....... It's about photography, get out and try it. Here's one example using a grad on a flat horizon, I have more with mountains and trees as well. I darkened the edges in post to draw the eye in, was the same exposure in original photo.

Totally agree. Graduated ND's are a worthwhile tool...if used properly.

lev29 Loc: Born and living in MA.

rmalarz wrote:

ND filters do not change the range of light, only darken everything by the same amount. Think of an ND filter as sunglasses for your camera. The ratio of brightness between dark areas and light areas stays the same. --Bob

May I ask: What are the disadvantages of using a variable ND filter instead of, say, three ND filters differing only by how many f/stops they individually reduce the amount of exposure?

I do realize that the advantage of the former is that it's an "all-in-one," reducing the bulk and cost of carrying multiple ND filters. But there must be some sort of IQ loss, o/w why wouldn't they, the variable kind, simply take over the market?

Revet Loc: Fairview Park, Ohio

planepics wrote:

I'd like to try to get into long exposures since I... (show quote)

I got a 10 stop B&W ND filter from B&H for $70. It has given me some very nice long exposure photos. I also have a circular polarizing filter which gives me 2 stops. Now I need one in between and I should be good to go for most long exposures I would take.

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

planepics wrote:

I'd like to try to get into long exposures since I... (show quote)

If your goal is smooth water then set yourself and tripod up at a location that you are looking DOWN toward the water. If you must include the sky shoot on overcast day or use a graduated neutral density filters and adjust for the sky or don't use graduated neutral density filters and take care of the sky in post production.

jerryc41 Loc: Catskill Mts of NY

planepics wrote:

I'd like to try to get into long exposures since I... (show quote)

Here are a lot of links about ND filters. They are very versatile.

What we need, though, is a reverse ND filter - one that would brighten the scene. :D

http://digital-photography-school.com/step-by-step-guide-to-long-exposure-photography/
http://www.the-digital-picture.com/Reviews/10-Stop-Neutral-Density-Filter.aspx
http://www.cambridgeincolour.com/tutorials/neutral-density-filters.htm
http://www.alexwisephotography.net/blog/2009/07/23/neutral-density-reference-chart/
https://www.youtube.com/watch?v=ZpNtAXbaNr0
https://www.ephotozine.com/article/how-an-nd-filter-can-remove-crowds-from-busy-shots--27054

zigipha Loc: north nj

planepics wrote:

I'd like to try to get into long exposures since I... (show quote)

1. correct re still over/underexposed with longer exposure
2. I bought a $20 ndf. I tried some shots just to see if i liked what i was getting re the effect. From a 1kx1k image, they looked fine but I'm sure if i closely examined i could find issues due to quality or color cast etc etc. but i was just trying to see if i liked it. after a few outing, i bought a better quality ndf.

Some will say you won't be able to tell if you like something unless u buy the best; the limitations of the cheaper solutions will taint your experience. I disagree, as long as you are aware of the limitations.

I bought a $20 ir filter. tried a few shots and did not care for output (i got the same effect as is typically shows for if shots). Not buying the $200 version saved me $180 to go buy something else.

zigipha Loc: north nj

lev29 wrote:

May I ask: What are the disadvantages of using a variable ND filter instead of, say, three ND filters differing only by how many f/stops they individually reduce the amount of exposure?

I do realize that the advantage of the former is that it's an "all-in-one," reducing the bulk and cost of carrying multiple ND filters. But there must be some sort of IQ loss, o/w why wouldn't they, the variable kind, simply take over the market?

ND filters can suffer from "X" vignetting it the shot, especially for wide angle shots. The use of two polarizing filters to create the variable filtering has some weird interactions on some brands of filters and angle of view shots

You can google that and read up more on it.

Crwiwy Loc: Devon UK

planepics wrote:

I'd like to try to get into long exposures since I... (show quote)

Yes, a ND filter allows for much longer shutter speeds. It will also allow larger apertures for when you want a shallow depth of field.
As for cost - not all cheap filters are rubbish and the very expensive ones do not guarantee fabulous results (checkout some of the group tests).
Many people have achieved good results by using a (new) glass from a welding mask (giving perhaps 10 stops) or tried two polarizing filters on the lens to make a variable ND filter.
A cheap filter can be worth it to experiment with long exposures and a few $$/££ is worth a try rather than spend well upward of $100 for something you only use a few times.

pecohen Loc: Central Maine

rmalarz wrote:

ND filters do not change the range of light, only darken everything by the same amount. Think of an ND filter as sunglasses for your camera. The ratio of brightness between dark areas and light areas stays the same.
--Bob

This reminds me of a question that I've had for some time and that is why camera manufacturers don't put artificially low ISO settings on digital cameras. If you could set the ISO to 1 instead of 100 that would be like putting on an ND7 filter. The necessary change to camera firmware for this would be trivial.

Does anyone know of a camera that does this kind of thing?

zigipha Loc: north nj

Iguess it depends on how they woudl achieve the effect.

if they could put in some grey glass inside the lens, that would work

but trying to make the sensor "act" like iso 1 would be a challenge.

Its much easier to increase the high end of the range of iso - you basically multiply the values from the photo sites to get an effective higher iso (with all the bad things that go with that).

to get a lower one, you can't divide the value from the photo site. Its analog output. So if a sensor could do an iso 1, that means iso 100 would need 7 stops of digital multiplication (and get all the bad things that go along with that).

most things that can be done to get iso 1 would negatively impact iso 100. so thats probably why its not offered.

but with advances in technology..who knows

Cdouthitt Loc: Traverse City, MI

pecohen wrote:

This reminds me of a question that I've had for some time and that is why camera manufacturers don't put artificially low ISO settings on digital cameras. If you could set the ISO to 1 instead of 100 that would be like putting on an ND7 filter. The necessary change to camera firmware for this would be trivial.

Does anyone know of a camera that does this kind of thing?

I think the dynamic range would be compromised too much if this was done.

lloydl2 Loc: Gilbert, AZ

I've recently learned that there are now ND filters available where you can dial in the degree of darkening in 1/3 stops.. I haven't had a chance to do any research on these I know they are rather expensive. I learned about it in a photo class at a local camera store from the instructor.

planepics Loc: St. Louis burbs, but originally Chicago burbs

pecohen wrote:

This reminds me of a question that I've had for some time and that is why camera manufacturers don't put artificially low ISO settings on digital cameras. If you could set the ISO to 1 instead of 100 that would be like putting on an ND7 filter. The necessary change to camera firmware for this would be trivial.

Does anyone know of a camera that does this kind of thing?

I know that I can set my A77 to an ISO of as low as 50.

speters Loc: Grangeville/Idaho

rpavich wrote:

Yes, an ND filter won't fix the contrast differenc... (show quote)

You do not have to jiggle the card (in fact try to avoid that), best is to keep it close (out of the focus range), preferably against the sunshade, so you can keep it steady and in one place! You don't jiggle your ND grads either ( preferably hard edged)!!

pecohen Loc: Central Maine

Cdouthitt wrote:

I think the dynamic range would be compromised too much if this was done.

An ND1 filter, at least in theory, divides the light intensity at each pixel by 2. With an ND2 filter the divider is 4 and with ND3 it is 8, etc. These operations would be quite easy - not just in theory - to perform in software. It is especially easy with the RAW data that the camera has readily available.

Sure, the consequences might not be good for your image if you don't do something to compensate, such as take a longer exposure, but that is why you want to use the filter.