Adjusting input levels to eliminate "haze"

I got serious and went to a dSLR this year, a D80 w/ 2 SB-105s. Just back from my first big trip with it. I've noticed that many of my pics, especially macro, have a sort of hazy look, which gets a lot better when I adjust levels and move the input sliders to the top and bottom of the curve. I know, post-processing 101. Anyway, what can I do to improve my photos in-camera so I don't have to do that as much? Or is that just part of digital imaging reality?

Thanks,

Tim

I got serious and went to a dSLR this year, a D80 w/ 2 SB-105s. Just back from my first big trip with it. I've noticed that many of my pics, especially macro, have a sort of hazy look, which gets a lot better when I adjust levels and move the input sliders to the top and bottom of the curve. I know, post-processing 101. Anyway, what can I do to improve my photos in-camera so I don't have to do that as much? Or is that just part of digital imaging reality?

That's part of the gamma settings used in the JPEG algorithm, i.e. the gamma is too high. Try shooting Raw (or better, Raw+JPEG); then convert a few raw files and compare them to what the on-board image processor hands you.

That's part of the gamma settings used in the JPEG algorithm, i.e. the gamma is too high. Try shooting Raw (or better, Raw+JPEG); then convert a few raw files and compare them to what the on-board image processor hands you.

That makes sense. Do you recommend a particular raw converter that does a better job with it, in your experience?

Also, newbie confession time - I shot in Raw+JPEG, but have primarily been messing around with JPEGs until I get better w/ post-processing and separate the wheat from the chaff (takes too long to process Raw for the not-good pics). I'll try your advice on some of my keeper pics, thanks.

Tim

Arghh. This is not because "gamma is too high". This experience is normal.

Contrast is reduced because you are shooting through water and through additional optical elements. The more particulates in the water and the more water, the worse that is. A low contrast image, when properly exposed, will have a high black level. Shooting close, with good optics, will minimize this. Some underwater images don't have that much dynamic range anyway.

The simple fact is that underwater images don't frequently look like land images and in-camera software isn't optimized for them. Authors of the in-camera JPG code are expecting the image to look like something taken on land so, as a result, they choose a black level too low and the result is a hazy, washed out image. You are seeing this and responding to it by raising the bottom slider up in the levels control.

Look at it this way: if you take an image of a white wall, the result will be "highlights" from corner to corner. The in-camera software isn't going to assume that any of it should be black so it can't really determine ever what blacks should be. What is happening in your case is the camera thinks that the image should have that "haze" because, technically, it really is there. We want our images to look better than that, though.

The way to deal with this is to shoot raw, get your exposures correct, then set your black levels appropriate to your image. You may want to set your contrast, brightness, and curves to linear first, get the exposure control, white balance, and blacks correct, then adjust contrast, saturation, etc. to make your images pop. When done properly, a side effect of this is that backscatter is better controlled.

P.S. There are no "gamma settings" in the "JPEG algorithm". There is a gamma associated with the color space conversion that is applied (but that's invisible) and there is a tone curve. Tone curves and gamma are not the same thing.

The way to deal with this is to shoot raw, get your exposures correct, then set your black levels appropriate to your image. You may want to set your contrast, brightness, and curves to linear first, get the exposure control, white balance, and blacks correct, then adjust contrast, saturation, etc. to make your images pop. When done properly, a side effect of this is that backscatter is better controlled.

Sounds like I have more homework to do. Thanks for all the advice, I'll go back and work with RAW with those suggestions.

Or stick with jpegs and set the D80 on Vivid.

I dont have the time, storage space or software to deal with RAW.

Or stick with jpegs and set the D80 on Vivid.

I dont have the time, storage space or software to deal with RAW.

When I first started shooting digitally, I shot TIF files (an option). Kurt Amsler noticed me doing this and said that if I wasn't shooting in RAW I was missing the point of digital photography! He was right, of course.

When I first started shooting digitally, I shot TIF files (an option). Kurt Amsler noticed me doing this and said that if I wasn't shooting in RAW I was missing the point of digital photography! He was right, of course.

All camera manufacturers supply at least rudimentary raw software with any camera that can write raw files -- Even prosumer P&S!

One big advantage of raw is that, as software (and user skills!) gets better over time, you can go back and re-open the raw files and get better results.

If cost is an issue, Google's free Picasa will get you started, as it has extensive camera raw support. Give it a try, as you may be surprised with it.

In any case, even if you don't want to shoot raw at this time, set your camera for RAW+JPEG mode: If you get the shot of a lifetime (but the exposure is way off) you can more easily salvage it on your PC from reconverting it manually. Also, even if the exposure is good and you want a 30x40 inch print, you can simply give the RAW file to the lab and they'll take it from there.

So now you know how to do it then John.... Dust off that old P&S......

Hey I just thought - when your skills get better you can go back and 'touch up' some of your 'granny' shots from yesteryear!

Am off to the Red Sea Thursday, Monday I find the the Ike D200 housing is stress fractured, looks like it's no camera this trip then, bummer

Paul C

So now you know how to do it then John.... Dust off that old P&S......

 

Hey I just thought - when your skills get better you can go back and 'touch up' some of your 'granny' shots from yesteryear!

 

Am off to the Red Sea Thursday, Monday I find the the Ike D200 housing is stress fractured, looks like it's no camera this trip then, bummer

 

Paul C

My granny shots were immaculate - thanks to perfect technique and an eye for the right angle! How did you like my HMS Myngs shots?

John, I went to your website but didn't see the HMS Myngs shots... Do you have them online? [more]

My granny shots were immaculate - thanks to perfect technique and an eye for the right angle! How did you like my HMS Myngs shots?

Paul, many newer point & shoot cameras do indeed have a RAW file option. (My editor's 4 year old Fuji S5000 has it; and all he shoots is RAW).

Furthermore, not only does RAW converter software improve over time -- Take a look at DxO Optics Pro 5 -- but also your skill and techniques get better, as you learn the in's & outs.

So now you know how to do it then John.... Dust off that old P&S......

 

Hey I just thought - when your skills get better you can go back and 'touch up' some of your 'granny' shots from yesteryear!

 

Am off to the Red Sea Thursday, Monday I find the the Ike D200 housing is stress fractured, looks like it's no camera this trip then, bummer

Tim,

In camera JPG has it's place in many kinds of photography, but underwater images are hard to get, you don't take many, and you don't often get a second chance. Frequently you willwant to pay more attention to each image than you may on land shots since lighting and various conditions vary so much. While not everyone believes in RAW, underwater is an example where RAW shows maximum benefits. I personally feel that underwater should always be shot RAW.

As for converters, an easy one to obtain is the one that comes in Photoshop. The same converter is found in Lightroom, and if you are a mac user then Aperture is an option. There are a number of other highly regarded converters as well. Each product has its proponents and each is differentiated by workflow features that may or may not be important to you. Some are intended for shooters that have lots of images to process on a deadline and that's usually not what underwater is about. I'm not aware that any converter has features that make it specifically better for underwater shooting, though I'd love to be corrected on that.

The best way is to look for comments and reviews on various converters, remembering that your computing platform will limit your options. I'm confident you can get good results from any converter if you invest the time to learn how to use it properly. Discussing the merits of various raw converters is not only a thread without end, it could possibly end up in a feud. :-)

P.S. As for granny shots and point and shoots, the forum is best served when people refrain from constantly taking threads off topic. It's not that such chat isn't welcomed, it just needs its own thread. Tim has asked some specific questions and it is most helpful to him, and to other readers, if the replies remain relevant.