Astronomy, Photography and Weather
June 22, 2024, 11:06:10 am
Welcome, Guest. Please login or register.

Login with username, password and session length
News: IAA lecture programme continues alternate Wednesdays from September - an excellent programme of lectures- Queens University Belfast - Bell Lecture Theatre. Also keep an eye out for the Summer Events
 
  Home Help Search Gallery Staff List Login Register  

Daffs

Pages: [1]
  Print  
Author Topic: Daffs  (Read 387 times)
JohnC
Hero Member
*****
Posts: 1631

Gloucester : UK


View Profile
« 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

Share on Facebook Share on Twitter

brianb
Hero Member
*****
Posts: 1228



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

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

Quote
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.
Report Spam   Logged
rjgjr
Guest
« 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!
Report Spam   Logged
JohnC
Hero Member
*****
Posts: 1631

Gloucester : UK


View Profile
« 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 ?
Report Spam   Logged
markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #4 on: March 28, 2010, 06:18:17 pm »

Daffs are finally out properly here for me now.  Nice pictures!  Smiley
Report Spam   Logged

JohnC
Hero Member
*****
Posts: 1631

Gloucester : UK


View Profile
« 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.
Report Spam   Logged
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« 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!
Report Spam   Logged

JohnC
Hero Member
*****
Posts: 1631

Gloucester : UK


View Profile
« Reply #7 on: April 01, 2010, 04:37:05 pm »

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


Pages: [1]
  Print  
 
Jump to:  

Bookmark this site! | Upgrade This Forum
SMF For Free - Create your own Forum

Powered by SMF | SMF © 2016, Simple Machines
Privacy Policy