Grad ND advise

Hi all,

Having just aquired a P mount and a few filters I thought I'd try out the graduated ND4 as the sky today looked interesting.

[IMG]http://i1236.photobucket.com/albums/ff444/Frogherder/IMGP1155.jpg[/IMG]

Camera on a tripod with the skyline nominally 1/3 the camera picked the sky to meter on.

I'm moderately happy with the sky but the field is too dark - thought that was what grads compensated for?

What have I done wrong?
By the way the dark bit of the grad was at the top.
It does brighten up in PS, but I'd rather get it right first time

regards
Bernard

The sky is too dark as well, that's what's wrong with it

Most filters will take some getting used to with regards to exposure, try metering of the grass and locking the exposure before sliding the grad down and taking the shot.

Without teaching you to suck eggs I hope that the next few lines will offer some tips and pointers.

The ND Grad is used to balance the exposure between bright areas and darker areas. However, you also need to know the difference in stops in relation to the light and dark areas and then use an appropriate ND grad to balance the scene out. By sliding the filter up and down within the filter holder you can move this light transition to the desired effect.

Other people have written info about using ND Grads so I have posted a few links which may also help.

http://www.nathangriffin.com/technical/how_to_graduated_nd.htm

http://www.ephotozine.com/article/tips-on-using-a-neutral-density-filter-4871

This site covers a lot of photography areas and is well worth a look

ttp://www.cambridgeincolour.com/

Alan, I don't think I've quite mastered locking the exposure, I frequently get a second beep when I shift the focus position - must try harder.

For the record the Sun was shining strongly on the left of picture, pic probably 60 degrees to the sun

I metered the sky because this was through the darker part of the grad, so I expected the grass to be a lot lighter than it tured out. It wasn't until I got home I could see the problem (too late) as it wasn't all together apparent out in the field.

Fletcher, The grad I have is a ND4 soft grad so determining the transition point is iffy in bright sunlight

Thanks for the links - not come across the 1st one, but was aware of the 2nd.

Looking at it again I think I might have had the grad too low in the holder as the only bright grass is at the very bottom. I'll see what weather is thrown at us tomorrow and maybe have another go.


thanks again
Bernard

I think it is just a wee bit under-exposed, I don't think the position of the grad is wrong. With a bit more exposure, this would have been a lovely image and the sky would not have been too bright.

Regards
David

You don't need the camera to your eye to do it, just point it in the direction of the ground and half press the shutter followed by the exposure lock, which you should have no difficulty finding as you can clearly see the back of the camera, you should be also be able to begin sliding the filter into place as your raising the camera to take the shot.

Much easier to apply Grad filters in PP IMO.

David - Thanks, I'll have to try again another day - weather here today is missly rain and total grey overcast so today is clearly out.

Alan - So do I meter without the grad in place? I did 1/2 press followed by AE-L and got a beep. Repositioned camera, then got another beep when I pressed the shutter again to take the pic and heard the focus shift, then shot taken. I'm clearly missing something as when I meter through a plain ND4 I get what I expect.


Smeggy - I'm trying to avoid PP, I'm not very good at it and I would rather get it 'right' if I can. But I take your point, for some it will be easier.

regards
Bernard

Bernard, can I be cheeky and ask which filters, brand name. you have as I am thinking of going this route. Was looking at a Cokin "P" holder and a ND4 hard and soft. Premier Ink have some Kood which are within budget. Am I feeling the width rather than the quality methinks

Yes, meter for the grass without the grad in place, (it doesn't have to be totally out of the holder)
I say meter for the grass but I suppose as long as you keep the sky out of the frame you could try metering from anywhere, it's still not going to guarantee a perfect exposure it's more of a quick fix to improve what you've been getting.

You could also try using the camera in manual, once you've metered from the grass and set the exposure you can take as many shots as you like with the filter in various positions, the only thing you have to worry about then is if the light is changing dramatically.

Another approach (that might be a touch quicker) would be to use spot metering. Raise the filter so that a clear part is over the centre AF spot, take a reading (and lock it), lower the filter and "Hey Presto"!
Results will vary depending on the colour/reflectance of the part of the image that is in the "spot"!

Stan was asking about filter brands - I would recommend HiTech filters - pricewise not the cheapest, but they don't appear to suffer from as much colour-cast as some cheaper makes (although this can be removed fairly easily in PP) and they are compatible with Cokin P holders. If price is not a consideration then many people swear by "Lee" filters.

This photo was taken with stacked filters on one of those horrible bright white cloud days link

Thanks LennyBloke, I'll have to shop around. Have heard of Lee filters and I think Lottery win was mentioned in the same quote

For me, if using a grad (or simply using a camera on the tripod) it's far better to go into Manual mode. That way you are in control, not the camera.

Thanks guys, I frequently use manual when the camera is on a tripod (I wasn't thinking I suppose). So in a sense it serves me right for not being too critical in the field.


Sorry to belabour the metering but,
If I meter the grass with the filter out (or at least through the 'thin' bit) the sky will be blown out, so putting the 'thick' bit over the sky darkens it up again -- happy with that.

If I meter the sky through the 'thick' bit anything then seen through the 'thin' bit will be much lighter -- This is were I'm still puzzled as the grass patently wasn't lighter


Stan the filter & holder are from Premier - Kood P series. I thought it was time that I tried out grads but felt I couldn't justify very expensive ones until I know why I need them. They are plastic so I suppose by the time I've got scrathes on them I should've figured it out

regards
Bernard

That's because the difference in required exposure between the sky and the ground was not balanced out correctly by either the positioning or the density of the filter, this is why it's always a good idea to base the actual exposure on the grass which is just about the nearest thing available to an 18% grey card.

To use ND grads correctly you really should be taking meter readings from both the foreground and sky and working out how many stops difference there is and then using the required ND filter, even then you may have to try a few exposures to determine the optimum position of the filter in the holder.