Steve - I have been trying to get action shots of Noi throwing things in the air, I've tried Lotus flower petals and now while we were in Lumduan, close to Surin I got her to throw these seeds from the local trees. My question is how can you try and get everything in sharp focus when you've only got seconds to shot the pics?

Charles –

This is an easy but not so obvious one.

What you want to do is pre-focus, lock your focus, and then all you have to do is snap the picture when she throws things up. 

You can do this by putting your camera into manual focus, focus on her closest eye, focus until you get the “in focus” indicator light in your viewfinder... and make sure there is enough DOF through the use of your aperture/focal distance/focal length combination to take into account the different plain of focus from her eyes through the leaves.  For instance, if you were using a 24-70 lens at 70mm and were about 15 feet from her.,. then F8 would do the trick.  Maybe even F5.6 depending on how the leaves flew.

With all the settings pre-set.. it’s just a matter of pushing the shutter release.  This is much faster than pushing the shutter release and waiting for the cameras CPU to autofocus, autometer, and then take the picture.

I hope this helps



Hi Steve,

My name is Ged from the UK and I would like to ask about full-frame sensors. I am new to photography but am looking toward the future in so much that I own now a Sony A350, but when the time comes I would like to go FF i.e. the A900 or similar when the time comes. Could you explain the benefits of it, not so much the tech stuff but benefits to me the end user, also I read in several places on the web, that if I go FF then any lenses I own that is designed for cropped sensor SLR will be useless on FF, what is the effect of using these lenses on FF camera, Is it advisable to buy lenses now designed for FF, if so are there any effects of using these lenses now on my A350? I also read about number of pixels: sensor size ratio, and problems with noise etc, with this in mind is there an OPTIMUM number of pixels for a given sensor i.e. can you have too many.

Sorry for all the questions mate, hope you can help. please fell free to edit the above as you see fit.

Many thanks in advance, and please keep up the good work, the articles are very informative and so interesting, again thanks

Ged (UK)

Ged –

Thank you for being so patient.  I arrived home this afternoon and am busy answering my emails and yours is one of the first on the list.  Allow me to answer your question on the layman’s terms you requested.  What exactly in real terms are the advantages for you in selecting a full frame sized sensor?  I’ll list my answers in order of the priority that’s important to me:

  1. Image quality.  A bigger sensor is like a bigger sheet of film.  You can put more on it.  This doesn’t necessarily mean you can put more of a vista or landscape into the frame, but it does mean that for a given area of that vista or landscape that you can capture more/better information during the recording process.
  1. As an example use this simple analogy:  If you were given a full sheet of notebook paper and were asked to describe the scene in words, you would have so much space to do so.  Now, if you were only given half a sheet of notebook paper and were asked to do the same thing, you can immediately see you could never record the scene with the same amount of accuracy or depth.  The size of the notebook paper limits you either way, but the smaller paper limits you more.
  1. Focal Length of Lenses:  Almost without exception the best lenses are made for full frame cameras in the focal lengths most useful.  Yes, these lenses can also be used on crop frame (APC-S) sensor cameras, but then you must multiply the focal length by either 1.5x (Nikon/Sony/Pentax) or 1.6x (Canon) to get the true focal length.  I.e., a 50mm lens becomes a 75mm lens on a Nikon DSLR APC-S camera.  Sometimes for subjects such as birding, certain wildlife, or sports, this can be an advantage.  Generally however it is not.  A 24-70mm lens is designed to be used on a full frame camera at distances calculated to be the most useful.  If you multiply those distances by 1.5x they are not as useful in most cases.  There are technical aspects in this area as well, such as maximum resolution of  given lens, then the maximum resolution of the same lens when you’re only using the center part of the lens (APC-S sensor use), but these are better discussed as an advanced topic.
  1. Generally you cannot use lenses designed ‘only’ for APC-S (crop sensor) cameras on full frame cameras.  The cameras that do allow this show a dark circle around the image where the sensor is larger than the lens making them not very useful at all.
  1. Optimum number of pixels per sensor space:  Yes, given the exact use of the camera, the most common ISO to be used, available light, and so on.. and the most current technology available.. you could probably say a certain number of pixels per given area is better than another number.
  1. Lets take Nikon as an example.  They make a full frame 12mp D3 and a full frame 24mp D3x.  Both are great cameras.  The D3 excels in low light, sports and other functions where you need to save a lot of data to the flash card as quickly as possible, and so on.  The 24mp D3x excels at capturing the most resolution and detail given adequate light, but it takes longer to process/store 24mp of data than 12mp of data, so it takes longer to capture/save a given number of frames.  After a certain point, the less light available, the more advantage goes to the 12mp D3.  These are very simple points we’re looking at, but if you match them to your needs the choice becomes more clear.  Many photographers have both a D3 and D3x.  They take one out of the bag over the other depending on their current needs.
  1. There is no ‘perfect’ DSLR.  The DSLR which fits you the best, will be the DSLR which fits your style of photography the best.  Generally a full frame sensor is a big advantage.  Generally the focal lengths of lenses used as designed would be a big advantage.  You need to examine your style of photography and equipment needs carefully before making your purchase.

I hope this helps.




Firstly many thanks for your reply and yes it does help, I will no doubt have many more questions for you and I hope you don't mind me asking them, I must say that the way you put things across is possibly the best I have come across, so please keep it up. I know you must be very busy  and will not in future waste your valuable time with thank you e-mails, please take it from me I am very grateful ,again a big thank you and keep up the good work.


p.s. I am hoping to come to Thailand in September during rainy season, I was on Koh Samet a couple of years ago an saw the most amazing lightening storms, I know these are possibly advanced techniques but maybe I get lucky LOL. Maybe I can buy you a beer in sept, take care and good luck.

Ged –

I’m glad I could help.  The beer sounds great!


Hi Steve,

Hope you’ve finally recovered fully from that nasty bug you had. Sounded pretty serious!

I’m glad you like my questions. I do appreciate you taking the time to answer them all. I know I can sometimes ask a lot of questions and it’s good to know I’m not getting on your nerves yet :p.

Just 1 question for now. I did take a few shots in Tanzania which I would like to try and process in HDR. I used EV bracketing with 1 full stop over- and underexposed. When I reviewed them on my laptop however, I did see that the photo’s don’t exactly line up. I moved the camera slightly when taking the individual shots (even while using servo I think). Is this going to be a problem, or is Photoshop able to line up the different images as layers correctly? I don’t have the time to work on this yet, but maybe I’ll have a few more questions when I try that. For starters I’ll have to install Photoshop, but I’m a little worried that my laptop can’t handle the extra strain of another imaging software. Even Lightroom is already taking a heavy toll on the processing resources.

Thanks again.

Best regards,



Hi Koen –

I’m back from the north today and answering emails.  Sorry it took so long to get back to you.

I’m going to run a learning section on HDR again.. I’m getting a lot of questions on this technique lately.  I suspect it’s being overused.. and used when it shouldn’t be.  But to answer your questions about alignment, yes the better they line up the better.  However, the better HDR software such as PhotoMatrix builds in some alignment features which helps line up the images when they’re slightly off.  Photomatrix also gives you choices on how it lines the images up, one choice perhaps better for certain images than another.  So, you can be off a certain amount in some cases with no ill effect.

Photoshop shouldn’t tax your system resources too heavily.  If you have the hard drive space then don’t worry too much about resources.  Lightroom uses much more of your resources, especially in a laptop, because the database features are hard disk intensive.

Eventually you’ll want to set up an inexpensive desktop for your image processing.  Much cheaper than a quality laptop, and the performance gains have to be seen to be believed.  For imaging, you want all the power you can get.  I’m running a 3 year old Core 2 Duo 2.66gig with 4gigs of RAM, two Nvidia 7950GT video cards, and over 12tb of storage.. and while it does okay.. the new i7 CPUs with say 8gigs of RAM would be sooo much nicer.  A new i7 motherboard, CPU, and RAM is about $600 USD if you shop carefully..  and will fit in my current case, use my current video cards, storage, etc.  So, once you get a decent setup.. upgrading every 3-4 years becomes cheap.

Not to mention a desktop LCD is hugely better for imaging than a laptop LCD..

I know you’re into computers pretty heavily, but if you need help spec’ing out a system let me know.  I’m fairly up to speed on what matters for imaging.. could help keep you from overspending.

Take care


Hi Steve if I want to take some HRD photos do I just need to change the shutter speed and leave the exposure where it is. And off course the focus.
e.g.; start at f5.6 and change the speed from 50>100>200>400.

Hi Charles –

I’m getting enough HDR questions that I think I might do next weeks learning topic on HDR.

On a very basic level here is the answer to your question.

  1. First evaluate the scene.  Figure out and know why you want to use HDR, what you hope to gain from it.  If you can do it without HDR then do so.
  2. Set up your camera either in manual or aperture priority mode.  Meter for the best overall histogram you can achieve and not the settings.
  3. Vary the shutter speed up/down from this reference point to capture the number of shots you want to process in HDR.  This might be a total of three, the medium and one up/down from the medium.  It might be five, seven, or more.  You might choose ½ a stop as your steps, 2/3’s, 1 stop, or a bit more.  It depends on the scene and what you’re trying to accomplish.
  4. HDR WILL NOT make a better image just because it’s HDR.  You must have a reason and plan for its use..

I hope this helps.


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