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Daffs

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JohnC
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« on: March 25, 2010, 05:54:16 pm »

These daffs. were near to home - in the Forest of Dean they still aren't out properly.  I assume that I can't have all the daffs. in focus.I placed the red focusing squares on where I wanted sharpness-in the foreground, the middle or the back,I tried many aperture settings including f22 which you'd think would have everything sharp front to back. Any thoughts. ??

Also, can anyone tell me why some photos, when exporting,  from Lightroom in my case but I assume it's the same whatever programme people have,  have to have the quality setting  reduced and reduced to get a photo to what a site's limits are - some 150KB . What are we limited to here by the way ?  ? I have asked before but didn't get a reply.

 The res. was  set at 72 in all three cases but I think the value of that only comes into play when a print is required. I have it at 280 when sending a photo to the newspaper and at 85-90%  quality rating most times and this gives me the required 3-4 MB for them.

So here is a photo with 3 different settings achieving 3 different KB sizes.  307Kb.(83% quality) 230KB( 50% quality) 123KB (20% quality). I expect it's something to do with how 'busy' a photo is ie. how much detail - loads of small flower heads will be a lot of detail I suppose. What this means to me is that photo 3 at 20% quality in order to get it down to 150KB isn't worth posting-it looks awful.  Any comments /advice much appreciated.









« Last Edit: March 25, 2010, 05:57:27 pm by JohnC » Report Spam   Logged

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brianb
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« Reply #1 on: March 25, 2010, 06:14:52 pm »

Ahh-tishoo! Must stock up on antihistamines .... thanks for the seasonal reminder!

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I assume that I can't have all the daffs. in focus.I placed the red focusing squares on where I wanted sharpness-in the foreground, the middle or the back,I tried many aperture settings including f22 which you'd think would have everything sharp front to back. Any thoughts. ??
Difficult. The way I do this sort of thing is to calculate the hyperfocal distance & set that on the distance scale (lens set to manual focus). Then everything between half the hyperfocal distance and infinity is tolerably sharp. The hyperfocal distance does decrease with a larger f ratio (more depth of field) but you may not be able to get sufficient to cover the whole scene ... with digital methods you could expose two images, one for the more distant areas & one for the nearer ones, and merge them, but it would be necessary to take care if the effect is not to look artificial. You could also try shooting "short" so that the more distant flowers are slightly out of focus & applying severe sharpening (unsharp mask) selectively to those areas ... which will give an impression of detail even though it's not resolved.

But the trick that works best is to stand further back and underfill the frame - so that you have to crop the image to get the composition you want - or alternatively use a shorter focal length lens from the same viewpoint; either of these will increase the depth of field & does not necessitate complex "fiddling" in the darkroom.

As for finished file size - the more detail is in the image, the bigger the file will be. I don't use Lightroom, just the JPEG quality slider in Irfanview (which is what I use for final cropping, resizing & conversion to JPEG) ... everything else is done in RAW, TIFF or FITS, full size & uncompressed.
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rjgjr
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« Reply #2 on: March 25, 2010, 10:42:10 pm »

Again, beautiful shots John, lovely carprt of daffodils. Ours finished blooming in my area on the coast here in Oregon about 2 weeks ago, but our weather isn't nearly as harsh and cold as yours. Brian is exactly right in talking of the hyperfocal distance. I've heard this issue discussed to death. There are numerous websites that discuss hyperfocal distance and have online calculators. What I usually do with my cheapo kit lenes with no distance scale, is for instance at 18 mm, focus on something approximately 6.5 ' away at f/8, set your focus to manual, and everything will pretty much be in focus from 3' to infinity. The poor man's way of doing it!
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JohnC
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« Reply #3 on: March 28, 2010, 03:55:32 pm »

Thanks for comnents re. the focusing. That sounds a bot complicated,Brian-I think I'll go route 1 with Richard's poor mans' way LOl. I'm aware of this hyperfocal length and there are charts  but when I read about this  some just say to get everything in focus go to a high F-number which of course I was aware of. I'll take another look at this hyoperfocal length.

Do you know what the KB limit is on here is please ?
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markt
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« Reply #4 on: March 28, 2010, 06:18:17 pm »

Daffs are finally out properly here for me now.  Nice pictures!  Smiley
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JohnC
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« Reply #5 on: March 29, 2010, 02:33:55 pm »

Cheers,Mark. I'll go and get the paper and see if this one made it.

Off to the Severn Bore tomorrow if it's not rain ing too much.
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martinastro
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« Reply #6 on: March 29, 2010, 03:11:38 pm »

Beautiful Spring images John - looks like a fairyland somewhere - I haven't seen that many daffs over here yet. Love the pics!
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JohnC
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« Reply #7 on: April 01, 2010, 04:37:05 pm »

Cheers,Martin,one of the few half decent days for light.Ugh.
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