???'s on Grad ND filters, if you don't mind...

kundalini

I am traveling to the Sedona Desert in Arizona around mid-September this year. If the gods be with me, I will arrive and be situated when the full moon rises. However, my delima is with the early morning, late afternoon shots... hell, all during the day in fact. This will be my first trip to the desert and my questions are with regard to Graduated ND filters.

I have done some research and realized that Cokin filters are not up to snuff for me as far as IQ is concerned, I don't think. I am leaning towards either Lee or Singh-Ray resin filters. I won't say this is a once in a lifetime experience and that these filters are exclusively for that trip, but I certainly want to get the best opportunity and the best results.

I am slightly ignorant to this type of filter system as I have only used screw on to date. I'm just unsure which filter size to really consider. Lee has it's own holder, but both Lee and Singh-Ray can incorporate the Cokin holder. I also understand that Galen Rowell was the developer of the Singh-Ray line (phenominal) and Lee is a quality contender.

So this is what I want to know as far as the size to consider with Cokin sizes:
P - 85mm x 85mm
X - 130mm x 170mm

I have 4x 77mm lenses (atm) and the one of most concern is the Nikkor 12-24mm f/4. I have a "feeling" that it will get a lot of use on this trip and want to avoid as much vignetting as possible. I "may" get to use a friends Sigma 10-20mm during this time as well *crosses fingers* for that extra 2mm in focal length.

Then, there is the next question. How many stops and should they be hard or soft as a beginner kit?

One more ???, Singh-Ray has a reversed Grad ND for those shots when the sun is sitting on the horizon. Any thoughts on the effectiveness?


Thanks for your thoughts and opinions.

Manfr3d

If you use the search function you will see some threads that give
good advice on nd filter strength and size.

You can avoid graduated ND filters alltogether if you use exposure
bracketing and merge the different exposures later in photoshop.

Art Scott

Manfr3d wrote:

If you use the search function you will see some threads that give
good advice on nd filter strength and size.

You can avoid graduated ND filters alltogether if you use exposure
bracketing and merge the different exposures later in photoshop.

Yes but sometimes that could mean as many as 10-20 bracketed frames to just get the ones you want to merge or stack.....

Personally I would go for the largest size I needed to not get the vignetting...also remember you will need a tripod to shoot like this.....also shoot with a Grad ND you should be in manual....then you could actually just hold the filter over the lens to not get a filter holder vignette.

pathfinder

I found I could just stand a large Singh-Ray GND filter on the long bar for my RRS pano bracket set, and I didn't even need to hold it - it would lean against my lens in just the right height.

But usually I just hold it in my hand in front of the lens, unless the exposure is more than 10 or 20 seconds.

Manfr3d

Art Scott wrote:

Yes but sometimes that could mean as many as 10-20 bracketed frames to just get the ones you want to merge or stack.....

Personally I would go for the largest size I needed to not get the vignetting...also remember you will need a tripod to shoot like this.....also shoot with a Grad ND you should be in manual....then you could actually just hold the filter over the lens to not get a filter holder vignette.

If I am not mistaken a modern DSLR has a dynamic range of about
5-stops. That is about half of what one would encounter in real life photo
situations. (See zone system: http://www.normankoren.com/zonesystem.html).
Therefore I would think that it is entirely possible to create a photo
out of 2 or 3 exposures with the same effect.

Considering the money, weight and setuptime in the field that
can be saved with bracketing I would seriously try that out at first.

kundalini

Manfr3d wrote:

You can avoid graduated ND filters alltogether if you use exposure
bracketing and merge the different exposures later in photoshop.

Considering the money, weight and setuptime in the field that
can be saved with bracketing I would seriously try that out at first

My Photoshop skills suck and am running an old version of CS.
I am patient with setup and the costs of the filters is secondary to quality. I won't be able to off-load the cards while away, so I would like to minimize bracketing. The D300 has around 8 stops of usable dynamic range anyway.

pathfinder wrote:

But usually I just hold it in my hand in front of the lens, unless the exposure is more than 10 or 20 seconds.

True, but sometimes I get the shakes. Age, Alcohol or Alzhiemers... hard to tell these days....:D

Art Scott wrote:

Personally I would go for the largest size I needed to not get the vignetting...also remember you will need a tripod to shoot like this.....also shoot with a Grad ND you should be in manual...

That was my thinking, to get the larger size. 95% of the time I shoot in Manual and instead of tranporting my tripod, I am going to rent one on arrival.

Manfr3d

I'm just saying. Googleing for "HDR tutorial" or "free HDR software"
and maybe buying a 50$ 8GB CF Card is alot cheaper and gives you better
results. Especialy when the horizon is not a straight line. But it's your
money

MT Stringer

So this is what I want to know as far as the size to consider with Cokin sizes

I just returned from vacation that took me through Colorado, Wyoming and Utah. Most of my landscape/scenic shots were taken with the Tokina 12-24 f/4 on a Canon 40d body.

I used a Cokin P Series holder with circular polarizer mounted in it and later switched to a graduated ND filter for a few shots (until I dropped it and garnered a rock chip!).

My goal was to slow my shutter speed down so I could get smooth flowing water in the shots of the mountain streams. Unfortunately, I was only partially successfull. 1/6 sec was the best I could muster. I went to several camera stores but no one had a neutral density filter that would fit my holder.

Here's a full image that shows plainly that at 12mm, you will get vigneting. I was prepared for this and learned I had to shoot at 14mm to eliminate the dark corners or plan ahead of time and allow for cropping.

As far the suggestions of bracketing the shots, I couldn't do that because I was as slow as I could get (1/6 sec, f/22/ ISO 100). The ND filter would have helped me but I didn't have it.

Hope you find this info helpful.
Mike

geospatial_junkie

Art Scott wrote:

Yes but sometimes that could mean as many as 10-20 bracketed frames to just get the ones you want to merge or stack.....

Personally I would go for the largest size I needed to not get the vignetting...also remember you will need a tripod to shoot like this.....also shoot with a Grad ND you should be in manual....then you could actually just hold the filter over the lens to not get a filter holder vignette.

Wow... why are you bracketing that many frames??? You would just need about 4-5, two at the extreme end of each exposure, two between the extremes and the proper exposure, and the proper exposure itself. From there you can modify as you wish since you'll have ALL the tonal information stored already. 10-20 exposures would take too long to get especially if working with disappearing light! Then, you have the problem of your white balance changing slightly.

Most of the literature I've read and the experiences I've had says that you wouldn't have to do that. Could you be more specific Art on when you would bracket that many exposures?

kundalini

MT Stringer wrote:

Most of my landscape/scenic shots were taken with the Tokina 12-24 f/4 on a Canon 40d body.

That's some serious vignetting MT. I don't know the Canon lineup too well, but if memory serves me right, the 40D is a cropped sensor. So is my D300. Hmmm..... Definetly keeping the larger size as a first option.

Sorry to hear about the mishap. Thanks for the info.

Anyone else want to chime in on the hard/soft gradient and suggestions on how many stops to consider?

Thanks

cmason

I have been happy with my cokin p filters, had no issue with IQ at all. I have found the soft grad more useful in more situations, since the hard really has only worked for me at the beach, where there was a hard, straight line on the horizon. The soft works better when you have trees and other objects that are not a good straight line. Btw, I find handholding this the best way to use it.

This was taken using a Cokin P ND 4 (not grad): (Sigma EX 10-20)
other examples in my gallery add a B+W Circ Polarizer as well (those shot beyond 20mm)

MT Stringer

That's some serious vignetting MT.

Yeah, the lens sees the filter holder sides causing the vignetting. I have heard of guys taking a Dremel tool to the holder to eliminate the sides that protrude.

BTW, I love the Tokina 12-24 f/4. I shot it a lot on manual focus because depth of field was so great at f/16 - 22.

Mike

Art Scott

geospatial_junkie wrote:

Wow... why are you bracketing that many frames??? You would just need about 4-5, two at the extreme end of each exposure, two between the extremes and the proper exposure, and the proper exposure itself. From there you can modify as you wish since you'll have ALL the tonal information stored already. 10-20 exposures would take too long to get especially if working with disappearing light! Then, you have the problem of your white balance changing slightly.

Most of the literature I've read and the experiences I've had says that you wouldn't have to do that. Could you be more specific Art on when you would bracket that many exposures?

That was an exaggerated example....somewhat not totally out in left field...I have bracketed +/- 5-8 shots....so that would be a total of 10-16 exposures................

As far WB changing....in reality WB is constantly changing...it is just not enuff that we notice it....so depending on how you bracket makes the difference between how much the light changes.....

I have done several landscapes without ND's and I did bracket +/- 5-6 exposures and then realized what a waste of time it is when I could have gotten what I wanted by spending a little money on a ND or 2 or 3..........and not trying to stack or hdr what I had.....and I was shooting at iso 64 for those particlualr shots.....

GND's are an investment and if they are good ones and taken care of then you can retieve most of your money when you decide to part with them.

kwork

I'm not sure which holder the user had, but there are at least 2 different Cokin P-holders.
1 holds a single filter and the other holds 3 stacked.
I don't doubt that the 12-24 would vignette badly with the 3-filter holder but I only remember having very slight vignetting at 12mm when I owned the Tokina lens and used it with the single filter holder. By 14mm it was gone completely. Keep in mind that you should not use the Cokin system on top of a UV filter because this will only magnify the vignette problem.

This problem can be avoided by handholding the filter against the face of the lens but I wouldn't recommend it for exposures less than 1/30th

I have the Singh-Ray reverse ND filter and love it for sunrise/sunset pictures. Some examples can be found on my smugmug landscape gallery. There's several recent shots using that filter.
For standard grad ND filters, the hard edge 2 or 3-stop filter is great if you have a flat horizon line. If there are trees or mountains across your horizon, you'll need to use a soft-edge filter. 3-stop is what I recommmend.