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Old Oct 19, 2008, 2:48 PM   #1
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http://forums.steves-digicams.com/fo...amp;forum_id=7

Maybe you can help me here?

Images taken with DL2 and Viv 90mm macro, postprocessed and cropped. I went for a DRI (dynamic range increase) approach here, with developing a bracketing series from one single RAW file.

The biggest problems (after the high dynamic range: strong sunlight + black fly body) I had was the resize for forum use - especially in the eyes I lost a lot of detail. Tried every resize method from "simple/fast", bilinear, bicubic, Lanzcos etc. - but am still not satisfied.

I'll attach a detail of the "front view" here, that was the approach where I think the combination of pre-sharpening (local contrast increase plus deconvolution active already when generating the bracketing images from the RAW, then upsizing and cleaning image after cropping and downsizing for print & forum use) worked best. Detail is a 1:1 crop from a 2700x1800 image, that I'll use for printing.

Regards,
Th.


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Old Oct 19, 2008, 7:57 PM   #2
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Hey Th, what is the question? Are you trying to increase the size or decrease it? I was assuming you were shrinking for forum use but I am not sure. I use PSP X2 and decreasing size is a pretty simple process so I am wondering if you are blowing it up?

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Old Oct 20, 2008, 2:51 AM   #3
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Hi,
you are right, decreasing size can be merely press a button, but the trick is HOW to decrease, there are different algorithms giving very different results. Also noise reduction, image cleaning, sharpening/detail works before resizing will (sometimes) help to give better results in the smaller image.

As for crops (the flies are like 30-50% crops) I found, that blowing up the image and use some image quality filters on the blown up image work better than on the small image. It gives a somewhat smoother result, which (to my mind) looks more natural. If you go the non-crop route (or cut just some %), that step isn't neccesary, granted.

What I am looking for is a way to resize images to like 600..1200 pixel width and give a crystal clear (not oversharpened, halo-spoiled, etc) small image. My small images still tend to look grainy, fuzzy, whatever you call it - although I certainly have more than enough image information to produce a clear small image. I seem to miss something here, that's why I ask. Maybe it's just my very defensive noise reduction approach, maybe I have to work way more with curves... am open for all advises.

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decreasing size is a pretty simple process so I am wondering if you are blowing it up?

Tim
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Old Oct 20, 2008, 6:57 AM   #4
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OK, I understand better now. I looked at PSP X2 and you are right, there are lots of choices. Mine is set to "Smart Sample" as default and I have never changed it. It does not increase noise for me, in fact, it generally reduces it significantly.

My workflow is generally to crop to a 4:5 ratio, correct contrast/brightness in curves, and apply USM (for a macro I am generally using .5 to 1 pixels, 70-150 strength, clipping 0 ). I then resize. If I feel the resize lost some detail I may give it a second very light hit of USM. The one below is done using that technique, it was an 1800 pixel crop on the long side, resized downwards to 800 on the long side, USM before resizing and slight USM again after.

I am wondering if you might be pushing the post processing too far before resizing on this one as it does look pretty grainy. I have never had that effect from resizing. Oh, and what are your jpeg quality settings set at when you save the resized image? Maybe they are too low?

Hopefully there was something useful in all that rambling,
Tim
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Old Oct 20, 2008, 8:21 AM   #5
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Hey
Thank you for the information - and yes, maybe I am pushing things too far. I had the flies sitting on a piece of wood and at the time I took the photos there were quite a bit of sunlight. Rather than just adjusting and stretching the histogram (the exposure compensation way) and using highlight/shadow etc. pp. I tried to produce a DRI image by combining multiple bracketing shots. So I loaded the RAW, set exposure to -2,-1,0,+1,+2,+3,+4 and saved the JPEG's. Then I combined them. This is where noise entered the scene from the +2/+3/+4 shots... but it also gave me good detail and resolution in the shadows, which is what I was after. Then normal postprocessing (histogram, cropping, color, whatever...) was applied and finally the resize.

Maybe a single, somewhat aggresive RAW development in the shadow regions might produce better (in the means of lower noise) results, I will try that later.

Or maybe it's just my very defensive noise reduction usage... I guess I should get some tricks in that area under my belt as most of the noise reduction tools weren't something for my taste.

I'll let you know about the outcome of a single RAW development.

Regards,
Th.


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I am wondering if you might be pushing the post processing too far before resizing on this one as it does look pretty grainy. I have never had that effect from resizing. Oh, and what are your jpeg quality settings set at when you save the resized image? Maybe they are too low?

Hopefully there was something useful in all that rambling,
Tim
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Old Oct 20, 2008, 2:31 PM   #6
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OK, here we go.

RAW developed with stretching histogram mainly, heavy noise reduction (my point of view), some highlight and shadow work, minor curves adjustment, custom WB. Stronger contrasts, moire in the eyes... it looksvery different.
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Old Oct 20, 2008, 3:46 PM   #7
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Almost the same, but coming from a 300% blown up image (done by RAW converter, method=Bicubic softer). Gives a somewhat smoother overall impression. *sigh* I think this is themaximum with that camera/lens/available light combo. Better results come with better magnification and better light (i.e. flash, which I didn't use in those pictures). Thanks for sharing your thoughts.
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