# When to use more than +/- 1 stops?



## lespaul (Jul 8, 2011)

Im a HDR newbie, so please excuse the naive question. 

I've been shooting HDR for the past few days and have noticed that some people shoot their bracketed pics with more than 1 stop - that is, +/- 1.3, 1.7, 2.0, etc.

Just wondering in what situations would I use a greater than 1 (eg. +/- 2 stop) over say just a +/- 1 stop? Is this best for low light shooting, outdoors, larger differences in color between subjects, etc..

 And likewise, in what situations would I want to shoot with a less than 1 stop (ie. +/- 0.7, +/- 0.3, etc). 

BTW, Im shooting 3 shots in RAW - using my Nikon D90.

Any feedback is appreciated.
Thanks


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## Bynx (Jul 8, 2011)

Ive been shooting HDR for a long time and I cant see any reason to shoot more than 1 stop between exposures. Too much is better than not enough. And 1 stop will give you a smoother look to your image. Those shooting anything else just dont know what they are doing.


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## thedigger (Jul 9, 2011)

I'm still trying to figure it also. I was thinking that adding over/under would be more defining to the difference between the lights and darks. I would love to figure this out. I see so many amazing shots in this style, but I've been stuck trying to figure it out just making adjustments with software to one photo.


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## Bynx (Jul 9, 2011)

There is an excellent example of an HDR shot put up by 480Sparky. It shows a forest scene through the open window of a darkened stone room. After applying all the shots the final pic shows so much detail and range, the light just didnt go from black to white, but with a whole range in between. To get each part of that range took a separate shot (9 in total). http://www.thephotoforum.com/forum/hdr-discussions/249367-hdr-shootout-23-9-evs-work.html
Thank dog light isnt laid down like a paint by number set with each part having a thin blue line around it. You want to capture it all so go for it all. At least 1 fstop between shots. And if your lighting situation didnt require it, what do you do? You use what you need. Use every second shot and you will have +2 stops between shots. How about every third shot (+3 fstops). Dont think too hard, and just take your HDR at 1 fstop and go home happy knowing you got it all. When you get home then sort it out.


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## SlickSalmon (Jul 9, 2011)

Bynx said:


> Ive been shooting HDR for a long time and I cant see any reason to shoot more than 1 stop between exposures. Too much is better than not enough. And 1 stop will give you a smoother look to your image. Those shooting anything else just dont know what they are doing.



The last sentence is unnecessarily provocative. Virtually everyone who writes on this topic, including Ferrell McCollough and the authors of the Photomatix users manual, recommend 2 EV between shots. One EV between shots was adopted early by users of cameras that could only autobracket 1EV. What is important is to make sure the entire dynamic range of the scene is covered. That sometimes requires more shots, but the range between shots remains the same.


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## 480sparky (Jul 9, 2011)

I'm with Bynx.  Take a ton of shots.  I've found myself taking 11, 13 even 15 in the field, just to CMA.  I may only use 3 or 5 in post, but I'd rather have 'em and not need 'em than need 'em and not have 'em.


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## Bynx (Jul 9, 2011)

Sorry if its unecessarily provocative, but sometimes the truth hurts. Even if its not whats written in some guys book. Im just talking from experience. Why autobracket 2ev when you can bracket 1ev? Boy, talk about cheap people trying to save on disc space.


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## Helen B (Jul 9, 2011)

Your D90 will take three autobracketed shots (and no more than three) at 2 EV intervals. That's a good reason in itself to use 2 EV steps - you don't really need 1 EV intervals, especially if you are working with 12-bit Raw files. 1 EV intervals were more important in the past, when sensors had less dynamic range and the output was at a lower bit depth.

Best,
Helen


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## Bynx (Jul 10, 2011)

Using the above files from 480Sparky I made HDR with Photomatix Pro 4. With same settings I used files 1, 5 and 9 for a 3 shot HDR. Then 1, 3, 5, 7 and 9 for a 5 shot HDR. And finally all 9 shots. You can see image improvement the more files you use, particularly in the trees and shaded sections of the stone.


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## Helen B (Jul 11, 2011)

Bynx said:


> Using the above files from 480Sparky I made HDR with Photomatix Pro 4. With same settings I used files 1, 5 and 9 for a 3 shot HDR. Then 1, 3, 5, 7 and 9 for a 5 shot HDR. And finally all 9 shots. You can see image improvement the more files you use, particularly in the trees and shaded sections of the stone.



Now I see the problem - you are using JPEGs, which are necessarily 8-bit and which have lost a lot of the range and fineness of the Raw file. No wonder you need 1 EV increments - you might even find that smaller increments will give better results. It's very different from using higher-bit Raw files and I'm surprised that you did not know that. In the light of this, it is a bit strange that you say "_Those shooting anything else just dont know what they are doing._"

Best,
Helen


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## 480sparky (Jul 11, 2011)

To be fair, Helen, jpegs are all he had to work with.  I didn't post the raws, since not everyone who participates in the Shootouts have the ability to pp raws.  And even if they do, they may not be able to handle Nikon's NEF format.  I posted all 9 EVs so members can pick & choose which ones they want to work with.  If they wanted to use the -4/-2/0/+2/+4 or the -3/0/+3, they're free to do so.


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## Bynx (Jul 11, 2011)

I did a quick 9 shot series for HDR raw Nikon NEF files. Processed with Photomatix after converting the NEF files to DNG with Adobe Converter. The first is the overall scene. Very bright outside and a single 60 watt bulb lighting the bookcase from the side. The closeups are 1. 3 shot HDR 3EV apart, 2. 5 shot HDR 2EV apart, 3. 9 shot HDR 1EV apart. All cropped shots at 100% view. No post processing at all. There is an improvement with the number of shots.







3 Shot HDR -- 3 EV apart





5 Shot HDR -- 2 EV apart.





9 Shot HDR -- 1 EV apart.


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## Dmitri (Jul 12, 2011)

Again I agree with Bynx. In my experience, it is better to have more source files than less. Once popped into Photomatix from LR, I definitely notice a difference when auto bracketing 2 stops, and when manually grabbing 7+ exposures 1 stop apart.


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## lespaul (Jul 15, 2011)

Hey Guys, 

Thanks for all your feedback. I guess there really is no difference in using 1,2,3 stops for HDR - just figured some situations would require more or less. I'll continue shooting with +/- 1 stop. Thanks


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## Dmitri (Jul 15, 2011)

lespaul said:


> Hey Guys,
> 
> Thanks for all your feedback. I guess there really is no difference in using 1,2,3 stops for HDR - just figured some situations would require more or less.



Did you read any of the replies??


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## 480sparky (Jul 15, 2011)

Bynx said:


> I did a quick 9 shot series for HDR raw Nikon NEF files. Processed with Photomatix after converting the NEF files to DNG with Adobe Converter. The first is the overall scene. Very bright outside and a single 60 watt bulb lighting the bookcase from the side. The closeups are 1. 3 shot HDR 3EV apart, 2. 5 shot HDR 2EV apart, 3. 9 shot HDR 1EV apart. All cropped shots at 100% view. No post processing at all. There is an improvement with the number of shots.



FWIW, I achieve the same results with a series of 0EVs and stack them using an astronomy stacking program, or even 'stitching' them with pano software.


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## lespaul (Jul 15, 2011)

HI Dmitri, 

Im going by the comments posted by Bynx and from personal experience. Of course I do see a difference between a 1,2,3 stop shots - its quite obvious. 

But my original question was in what SITUATIONS would I use 1,2,3 stop difference. Meaning, indoor/outdoor/low light, etc? 

From what I gather I should take as many source shots as possible and then "sort out at home". So the choice to use more/less than 1 stop really comes down to trial and error - nothing wrong with this, just figured there was a "rule of thumb" from pros.


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## Bynx (Jul 15, 2011)

Im no pro, but I can give you 2 cents worth of experience. If you have a light source, such as a light bulb, lamp, or sun and there are dark areas in the same image such as shadows or darker colored objects, then you need more shots. A 0 shot (best overall exposure) is a good place to start. Then common sense will tell you if there is a lot of dark areas you might need more overexposed shots. If there is a particularly strong bright area then you will need more underexposed shots. How many you need will depend on how much difference there is between the brightest area(s) and darkest area(s) and how much detail you want in those areas. I find that bright sources need particularly more underexposed shots than darker ones need overexposed shots. A problem with a lot of overexposed shots of dark areas is the noise which is created. Here is where experience comes in because not every lighting situation is written about. I dont know why people like Helen B make such a point of telling you to take as few shots as you can. Following that poor advice will have you wishing you'd not paid heed when you get home and start processing your images and wish you had taken a couple more exposures for some area that needs more detail in the  highlights, or more detail in the shadows. But its too late because you didnt take then. My advice is, if something is worth making a series of exposures for HDR, dont cheap out, take 7 or 9 or even 11 if you think you might use all the exposures. After you get home you can determine if you were right or not. But its too late if you dont have enough. And if you were wrong, you have a couple extra shots you dont need. Now which is better, two too many, or two not enough?


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## mjhoward (Jul 15, 2011)

Bynx said:


> Sorry if its unecessarily provocative, but sometimes the truth hurts. Even if its not whats written in some guys book. Im just talking from experience. Why autobracket 2ev when you can bracket 1ev? Boy, talk about cheap people trying to save on disc space.



Because if you only have a max of 3 bracketed exposures, and a range of only 2EV isn't enough to cover the dynamic range of the scene, you might want to use more than +/-1EV.  Assuming you're camera supports more than 3 bracketed exposures, perhaps your scene doesn't.  A slow moving scene (or a scene that has stopped momentarily) might only allow for you to get 2-3 shots before you have alignment problems, in this case you might also want to use more than +/-1EV for your exposure to capture a larger dynamic range.  Sure more shots with smaller EV gaps might yield a slightly better result, but sometimes you have to work with what your equipment and/or the scene allows.  Just my 2c.


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## Dmitri (Jul 15, 2011)

mjhoward said:


> Bynx said:
> 
> 
> > Sorry if its unecessarily provocative, but sometimes the truth hurts. Even if its not whats written in some guys book. Im just talking from experience. Why autobracket 2ev when you can bracket 1ev? Boy, talk about cheap people trying to save on disc space.
> ...



Every DSLR supports more than 3 exposures - it's called Manual Mode. Stay away from auto-bracketing and your limit is solved.


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## Bynx (Jul 15, 2011)

I dont think it was ever mentioned that you have to use more than 1 ev when there is no time to do it properly, as in the case of movement. If movement or speed in shooting is that important then I would just take one good shot and then process the raw file and make as good an image as I could get. If you have time to set up a tripod, mount the camera and get the exposure right, then there should be enough time to take 5, 7, or 9 shots quickly and manually. Any camera that is capable of shutter control can produce the files you need to make a good HDR. I dont understand why there is such opposition to shooting 1ev apart. I think Ive shown that there is improvement in quality as you go from 3, 2, and 1 ev. Now if you can show me there is loss of quality then by all means show me. If you want to shoot 6 ev apart go ahead. Everyone can do as they please. Just dont recommend it to others who dont know better. Of course those who dont know better can take the advice of either of the two sides here. Too many shots, or too few shots, the choice is yours.


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