Current digital sensors and Grad ND filters

[kuryan_thomas]

<p>What is the current thinking on the need for physical grad ND filters? Since many previous posts on this topic were made in this forum, DSLRs have gained a lot of highlight recovery capability, and raw processors such as Lightroom 2 have added software grad NDs that can control more than just exposure.</p>

<p>I'm curious if anyone here has bought a late model (2008+) DSLR and found that grad NDs are less necessary or just plain unnecessary.</p>

<p>Thanks.</p>

[andrew_gale]

<p>even modern DSLRs have less range than color film, until that changes its probably a good idea to hold onto your filters.</p>

<p>Also, why would you cut corners and save but twenty seconds when your taking the shot so that you have to spend twenty minutes in front of the computer later on?</p>

[howard_m]

<p>there is certainly a place for either GNDs or bracketing/HDR/fusing techniques.</p>

[david_henderson]

<p>I certainly use grads a lot less with a 5D than I do with medium format film cameras. Thats because i use slide film which is a lot more critical of over /under exposure than my digital sensor. I fear that the increased dynamic range I get with the dslr is making me lazy. </p>

[Tim_Lookingbill]

<p>I think I remember reading somewhere on these forums a while back that any filter that is placed in front of a DSLR lens is going to reduce light by certain amount of stops. Linear sensors don't render their best under these conditions due to signal to noise ratio issues and that the fact the first stop of the brightest portion of light captured is rendered to take up half the tonal steps of the entire tonal scale.</p>

[jtk]

<p>Acrylic filters at 45deg degrade detail and, used without proper shades, introduce flare.</p>

<p>Optical glass flats at 90deg to optical path are better, especially if used with a compendium (per motion picture practice...Harrison is/was a source).</p>

<p>LR2 takes moments to do most of what a filter would do...and with far more precision...the exception might be HDR, where optical performance seems less important judging from examples online.</p>

[jtk]

<p>Acrylic filters at 45deg degrade detail and, used without proper shades, introduce flare.</p>

<p>Optical glass flats at 90deg to optical path are better, especially if used with a compendium (per motion picture practice...Harrison is/was a source).</p>

<p>LR2 takes moments to do most of what a filter would do...and with far more precision...the exception might be HDR, where optical performance seems less important judging from examples online.</p>

[Ed_Ingold]

<p>ND grad filters are used to reduce the effective dynamic range of the subject. They are just as applicable to digital photography as for film. Most DSLRs have somewhat less dynamic range than color negative film, but much more than any reversal film.</p>

<p>You can't recover something that isn't there. If highlights are outside the dynamic range of the medium, they're gone. However JPEG renditions sometimes clip the highlights in order to produce more contrast and saturation. They're still there in the RAW images if you bothered to save them.</p>

[mauro_acchione]

<p>Pulling together multiple exposure is certainly a nice technique to have at one's disposal. But GND filters still have their place. Consider any longer exposure. What if you have something moving? It may not be a trivial thing to then blend such images. Or what if lighting conditions are changing rapidly in frame? Again, how easy is it going to match those different exposures?</p>