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View Full Version : Minimizing Lost def when straightening horizons.



Ian McHenry
04-22-2010, 11:28 PM
One of my pet annoyances is having returned from a holiday to find seascapes with sloping horizons.
What is most annoying is the loss of definition following straightening.
Just wonder if anyone else has the same problem and apart from being more careful in composing the picture is there a good quick way to solve the problem?
With Thanks: Ian Mc

Daniel Cadieux
04-23-2010, 06:32 AM
Ian, what is your method to straighten the horizon? When I need to do so I use the Ruler Tool to draw a line parallel to what the horizon should be, then Image>Rotate>Arbitrary...I do not lose any definition...

Tony Whitehead
04-23-2010, 11:11 AM
I use the same method as Dan and can see no reason for as loss of definition if all you're doing is levelling. If you're cropping and rotating and this involves downsampling you may lose some definition. Let us know how you're doing it - I'm sure the solution is in the method.

Ian McHenry
04-23-2010, 03:30 PM
Thanks Daniel & Tony
Ever since I started digital photography I've used Picasa for straightening.
This is so easy !!!
However will have to make an effort and learn how to do the straightening with PS Elements and see if different result. At least will be able to save as Tiff whereas Picasa only saves in Jpeg.
Cheers: Ian Mc

Ian McHenry
04-23-2010, 04:23 PM
Well I made the effort and glad I did.
Straightened with "Straighten" tool in PSE full edit.
Applied Noise Ninja.
Sharpened.
Thanks again to Daniel & Tony.
Very satisfying to do the "Kaizan" thing !!!
Cheers: Ian Mc

Tony Whitehead
04-23-2010, 05:07 PM
Looking good, Ian. Not sure how Picasa does it but that seems to be the issue.

Ian McHenry
04-23-2010, 05:30 PM
Cheers Tony
Ian Mc: http://www.pbase.com/ianmc

Daniel Cadieux
04-23-2010, 08:04 PM
Glad it got worked out!:)

Ian McHenry
04-23-2010, 08:34 PM
Thanks Daniel
Cheers: Ian Mc

Roger Clark
04-23-2010, 09:00 PM
I'll add to this discussion that a rotation is resampling and all resampling will lose a small amount of definition. I find that if working from a raw, I make the raw output as large as possible in the raw converter (or almost 2x, whichever comes first), and then rotate that larger image there is less loss of definition.

Roger

Ian McHenry
04-23-2010, 11:30 PM
Thanks Roger
As I'm still not comfortable with RAW I'll convert Jpeg to Tiff and then enlarge with Smilla Enlarger and straighten and see how this compares.
Cheers: Ian Mc

Roger Clark
04-24-2010, 08:14 AM
Ian,

There are several advantages to raw. The main one I find is better signal-to-noise ratio in the shadows, and better tonality in the highlights. Also some, but not all, cameras that produce in camera jpegs clip the high end by a stop or so, so on those cameras you get more highlight headroom with raw. You do need to work in 16-bit to realize the advantage of better signal-to=noise ratio and highlight tonality. You can alo choose/refine your color balance better with raw and 16-bit output allows you more flexibility in post processing.

The down side is more memory card space and disk space. I often shoot raw+jpeg and juts review the jpegs quickly. If fast action, then only raw to save write time to the card.

Roger

Ian McHenry
04-24-2010, 05:01 PM
Thanks Roger
I have tried the raw/jpeg combo a few times but my problem is lack of disc space on my computer also slooooow editing !!!! Still to edit some pix taken August last year like the one above. Fine tuning family pix always takes priority.
Cheers: Ian Mc