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Hi Everybody - Whenever I took scenery shots I was told to focus a third of the way up the frame - this is I was told the hyperfocal distance Is there a way of determining this point of focus more accurately and if so where do I get that for example for my 10-20mm lens?

I also heard that lenses have an optimum aperture for DOF - usually one or two stops inside the narrowest setting. Is this correct?

Please help

Regards Frans

You can get more accurate ways to tell your hyperfocal distance and I have posted some links below that should help. After a while you will get to know your hyperfocal distances so you won't have to refer to them.

Link to site regarding hyperfocal distance:
http://www.dofmaster.com/hyperfocal.html

Link To Printable hyperfocal calculator:
http://www.dofmaster.com/custom.html

Link to online hyperfocal calculator (nice to have a play with):
http://www.dofmaster.com/dofjs.html


Regarding your 2nd question then I think you are referring to the maximum aperature before becoming diffraction limited (DLA). I take it you obviously using a crop sensor DSLR ? using a 10-22mm lens but it depends on the body of your camera and not the lens. It gets lower the higher the denisty sensor so for example on a Canon 350D 8MP it is f/10.4 and on a Canon 550D/600D 18MP it is f/6.8.

Here is a site that could explain it probably better than me:
http://www.cambridgeincolour.com/tut...hotography.htm

You don't need a very high aperture with a wide/very wide angle lens on a crop sensor body to get a large depth of field. For example if you had a focal distance of 12mm on a crop sensor canon (x1.6) even at f/8 if you focused at approx 3ft (91cm) your DoF would be from approx 2ft (60cm) to infinity.

Hope the above helps but I wouldn't get too tied up in things like CoC or DLA if your taking good shots.

Hi Massimo - I learn every day Thank you for your reply and the links
We are at present in New Zealand (has been from end Nov 2010 untill end of Aug this year -) The scenery is breathtaking and the seabirds beautiful.

I have a Canon 400D and a 40D with a 100=400 L lens for the birds and a Sigma 10-20 for the sceneries. I will use the links you so kindly made available and will hopefully improve my scenery photos.

Once again -THANK YOU

Frans