HDR issue with focus points

topcat07

topcat07

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Attempted a HDR image at the weekend on a building.

I used spot metering on the building first with the middle focus point ,then tried to not move camera to get focus point on the sky but couldnt get the camera to focus on the sky without moving the camera

my focus points are set out as

{} {} {}

My plan was to to merge both of the images in PS

is there another method to do this if you can not spot meter the sky on the second shot?

i was following this guide but his camera can move the focal point to anywhere , where as mine are fixed

[YOUTUBE]http://www.youtube.com/watch?v=AWPLpz8uXjw[/YOUTUBE]
 
Why do you need 'focus' on the sky? If the focus is on your subject (the building) and the sky is in the shot, it will be in the shot. Using HDR you shouldn't need to meter for the sky as the HDR shots will be under/over and normally exposed.
 
I'm no HDR expert but I would do the metering before final composition and setting up on the tripod.
 
I have never really done any HDR but sure you would focus and compose the entire photo, using pattern metering. Then use bracketing to capture 3 snaps of different exposure levels.

Then afterwards merge and adjust them in PS?

I can't be sure but I don't think you need to meter on different areas like this, unless I'm missing something of course.
 
First meter for your main subject then the sky. Make a note of the 2 readings. This can be done off the tripod and will give you an idea of how many stops you need to bracket by. Then mount camera on tripod focus for main subject do not move camera or focus point during exposure. Merge in pp.
 
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vetonbike said:
First meter for your main subject then the sky. Make a note of the 2 readings. This can be done off the tripod and will give you an idea of how many stops you need to bracket by. Then mount camera on tripod focus for main subject do not move camera or focus point during exposure. Merge in pp.
Click to expand...

How do you change the exposure without moving the camera?

Surely to do this stuff you need a camera that can do auto bracketing for the best results.
 
Hi you use manual and best to change shutter speed than aperture. I do not know of your camera. But most modern dslr have the facility to set the bracketing amount.
 
connersz said:
How do you change the exposure without moving the camera?
Click to expand...

If the camera is on a tripod, you just adjust the shutter speed to manage the exposure. You'd want to keep the aperture constant so that your depth of field remains the same.

Like Melvyn said, if you meter for the highlights (usually your clouds) and meter for your shadows you get an idea of how many exposures you need.

Example: Set aperture to whatever you want. Point camera at highlights. It says 1/1000sec shutter speed required. Point camera at shadows. It says 1/15sec required. Set camera on tripod, focus on your subject. Manually adjust shutter speed to 1/1000. Shoot. Halve the shutter speed and reshoot until you get to the lower speed. (1/1000. 1/500, 1/250, 1/125, 1/60, 1/30, 1/15) You should then have an excellent dynamic range covered for post processing.

As to "how to get stuff in focus" - have a read up on Hyperfocal Distance or Zone Focussing. This presumes that your lens has a distance/focus scale on it though.

Ian.
 
Thanks for all of your input, great stuff :-)

I thought the way shown in the YouTube video was the only way but have researched some of your comments and found

' First you shoot the main shot and then you shoot the brackets. To do this you hold down the compensation button (the one with the +- sign on it next to the info button) and turn the thumb wheel three clicks to the left, shoot, then turn six clicks to the right, shoot again, and finally turn three clicks to the left so you leave it back on 0. This should give you your central shot with no exposure compensation, a shot with a compensation of +1 and a shot with a compensation of -1. If your scene has a very big range you can take 5 or even 7 shots continuing to bracket in additional increments of 1 in each direction.'

This sounds great in theory but I would imagine the tripod is going to move very slightly during the exposure changes? (I will try it out when I can but won't be able to until I buy a tripod)
 
No need to use exposure compensation, although you can do that way too.

Camera in manual mode, off tripod read brightest exposure through the meter and darkest, then onto the tripod, compose, lock focus, take "proper exposure' then simply dial the shutter speed up or down however many stops you need and take the shots as required. . If you have a decent tripod, it shouldn't move at all.

It is possible in good light to do HDR off tripod, but you need auto bracketing and a fast Fps rate.
 
topcat07 said:
Interesting! How would you keep the image exactly lined up when changing the exposure though or doesn't it matter?
Click to expand...

Set exposure bracket compensation (usually+2,0,_2), keep the same aperture, set high continuous shooting, use a high iso if required, compose ,shoot three rapid shots.
Providing your under exposure frame is still fast enough to avoid camera shake, it works well.
In fact when you use a tripod for long exposed hdr shots, it can be tricky.

Here are some handheld hdr examples -
http://www.flickr.com/photos/peter-young/8277474609/
http://www.flickr.com/photos/peter-young/8504170988/
http://www.flickr.com/photos/peter-young/8194182180/in/photostream/
 
connersz said:
How do you change the exposure without moving the camera?

Surely to do this stuff you need a camera that can do auto bracketing for the best results.
Click to expand...

You need a better tripod if you can't change the exposure setting without disturbing it. Although with the budget-end DSLRs that need a push-and-turn instead of having dual control wheels there is a wee bit more potential for nudging the camera - but nothing a decent tripod won't cope with.

Auto-bracketing on most cameras is very poor for HDR. If you can capture the scene with a 3-or 5- shot bracket over a +/-2 stop range, it probably wasn't a scene needing HDR anyway.


Watch your highlight and shadow clipping if you're auto-bracketing - because if you're still seeing it at either end of the bracket you haven't taken enough exposures.
 
Is there anyway to program a cable release or remote control to do the exposure altering?

(the camera uses a push button and wheel)
 
topcat07 said:
Is there anyway to program a cable release or remote control to do the exposure altering?

(the camera uses a push button and wheel)
Click to expand...

Depends on the camera.

I have a wired programmable remote, although it won't run an automatic sequence I can adjust each exposure on the remote. Only really useful when I'm getting beyond the 30 second maximum exposure on the camera (common for interior HDRs).

Other cameras have wireless remotes, and some of the latest have wi-fi remote (I think the most recent Canon DSLRS are going wi-fi).

You need to look up your camera.
 
27yr31f.png


Apolgies if I am misunderstanding here but if I am control the exposure with the shutter speed on the app why would I need to set the stops?
 
topcat07 said:
Apolgies if I am misunderstanding here but if I am control the exposure with the shutter speed on the app why would I need to set the stops?
Click to expand...

The stops is the shutter speed really. Centre is the shutter speed that is the correct exposure. Then the stops dictates how far over and under exposed the next shots are. So its on 2 stops, so the shutter speed has changed 2 stops below and 2 stops over the centre value.
 
TCR4x4 said:
The stops is the shutter speed really. Centre is the shutter speed that is the correct exposure. Then the stops dictates how far over and under exposed the next shots are. So its on 2 stops, so the shutter speed has changed 2 stops below and 2 stops over the centre value.
Click to expand...

Thank you very much it has all clicked now, happy days :-)
 
Peter10d said:
With fast shutter speeds, you can do hdr without a tripod:)
Click to expand...

Maybe so ive there very fast. I never shoot without my tripod unless im goin a portrait shoot and I rarely do hdr as it looks bloody awful 99% of the time. But I do bracket shoot and merge via masks
 
barratt1988 said:
Maybe so ive there very fast. I never shoot without my tripod unless im goin a portrait shoot and I rarely do hdr as it looks bloody awful 99% of the time. But I do bracket shoot and merge via masks
Click to expand...

apologies for my possible ignorance here but isn't HDR made up of bracket shots?

i thought bracket shots were all merged to make a HDR?
 
topcat07 said:
apologies for my possible ignorance here but isn't HDR made up of bracket shots?

i thought bracket shots were all merged to make a HDR?
Click to expand...

There are two different techniques. HDR, as you say merges entire images wi eachother.

Another, which technically isn't HDR as its commonly known is to to take a shot metered for the foreground and one metered of the background and sky, them slice in each bit to make a final image using layer masks.
 
topcat07 said:
Is there anyway to program a cable release or remote control to do the exposure altering?

(the camera uses a push button and wheel)
Click to expand...

Don't know if it works with a Nikon, but both my Canon's (1000D and 7D), if you use a count-down timer and burst-mode shooting with AEB enabled, it takes all 3 shots after the timer.
 
Not sure that the D40 has an AEB mode.
 
TCR4x4 said:
There are two different techniques. HDR, as you say merges entire images wi eachother.

Another, which technically isn't HDR as its commonly known is to to take a shot metered for the foreground and one metered of the background and sky, them slice in each bit to make a final image using layer masks.
Click to expand...

Exactly. I use nd fters but this sometimes helps with.complex shots. Hrd is ok when its very very subtle oyherwise its awful
 
topcat07 said:
Is there a name for the second method which I could research please?
Click to expand...

Not that im aware of its just one of those techniques known I guess. Its more to do with pp skill than anything else
 
Just in case anyone was interested in app I posted earlier found a few issues with it which maybe specific to my camera.

hdr doesn't work it will just takes a shot without leaving shutter up for correct exposure time wait x second then take another shot. Instead of keeping the shutter open for X amount of time then close then leave open a longer amount of time and close. Works well just as a shutter remote though
 
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