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View Full Version : UPsizing images - Best technique?



Marko
08-30-2013, 12:47 PM
Curious if anyone has an opinion on the best way to upsize images?

Here's 2 scenarios.

I have a Nikon D-700 - The native file resolution of my camera is 4256x2832. (12.1 MP) In camera Raw I have the ability to open up an image to this size - and the document at 300 dpi is 14.187x 9.44 inches. This is what I usually do in 16 bits.

i ALSO have the option to open any file in camera raw at 6144 x 4088 (25.1 MP) pixels and when I do it produces a document that is 20.48 x 13.627 inches

Seems to me that I'm definitely adding pixels in the second scenario....but I need to add pixels if i want the print larger than 14.187x 9.44 inches which i most certainly do.

So my question is this, is it better to open the file at the UPSIZED resolution?


OR


Is it better to open the file in it's native resolution and upsize it in increments of 10% until I get the desired size which is around 20 x 13 inches. This is a method that i have used before to upsize but never this large.


Curious to know if anyone has opinion on this?

many thx!

asnow
08-30-2013, 01:14 PM
Hi Marko

I've never used it, but I've heard that one of the best programs for doing this is Perfect Resize (used to be call Genuine Fractals). Apparently they have some secret sauce (algorithm) for adding those pixels. Perhaps somebody has used this and can comment. My 'very' vague recollection is there is a benefit to upsizing in increments.

Did a web search and the consensus is that doing it in increments is a myth. This may have been sightly true many years ago but not today. Two sources that say this is DPReview and Scott Kelby\Matt Kluskowski. Two sources that I believe would be reliable.

Marko
08-30-2013, 02:18 PM
thanks asnow!
reference links would be appreciated if u still have them. Thx!
Dp review is reliable only if the people posting know what they are talking about.... :)

Runmonty
08-30-2013, 06:13 PM
I think one way or another you will be adding pixels. The question is, what is the best way to add pixels. The most recent version of photoshop CC has a new upsize algorithm that is supposed to be quite good and much better than before. I did one for my niece that seemed quite good but I had nothing else to compare it to and I still havent seen the printed version.

Barefoot
08-30-2013, 11:10 PM
Hi Marko I've never used it, but I've heard that one of the best programs for doing this is Perfect Resize.

I've mentioned Perfect Photo Suite (includes Perfect Resize) here a few times, but I don't think many paid much attention. I'm telling you, boys and girls, it a powerful piece of software. If you download one of their free versions of any one of the individual components you'll soon receive an offer from them to purchase the entire suite at a greatly reduced price. Worth every penny.

Marko
08-31-2013, 09:22 AM
Appreciate the input BF - will check it out.

Iguanasan
08-31-2013, 11:10 AM
I'll be interested to see the results of whatever method you choose. I just listened to a photographer podcast the other day that suggested that if you simply open it in Photoshop and then double the size it nets the same result as opening it and then upping it in 10% intervals. I've tried neither but I'd be interested to know if there is a difference.

ericmark
01-05-2014, 03:37 AM
I am uncertain to if opening at 25M if you are adding pixels or if opening at 12M you are subtracting pixels? With my Nikon D7000 I do have a problem with the large RAW image size of 18M when trying to take a series of images connected direct to the PC and at 25M it would be even worse so it would seem to offer the user the option to take pictures at a lower size would be helpful with certain situations. I have needed to set to take as jpeg before now to be able to down load direct using Pentax Remote and with SM Tether it only downloads the jpeg and leaves the RAW on camera not sure what the official program does.

I wish my D7000 allowed me to select a lower pixels RAW image your camera clearly leagues ahead of mine.

Marko
01-05-2014, 11:44 AM
The D7000's max res is Maximum resolution, 4,928 × 3,264 (16.2 effective megapixels). So if you open the file at 25 M (or anything over the native resolution) - 100% you are adding pixels and sacrificing image quality to some degree. To WHAT degree? This is the 64,000 dollar question......and....This whole question was beautifully answered in a podcast interview w/ Royce Howland. Hope this helps.

How Big Can I print that Photo - Interview with Royce Howland | Photography.ca (http://www.photography.ca/blog/2013/09/22/how-big-can-i-print-that-photo/)

ericmark
01-06-2014, 06:00 AM
I do agree and of course sharping is also a question some cameras today do not have any mask, but in the main I don't print so I have to reduce the image to 1400 x 1050 pixels to match the projector. Focus is normally the limiting factor on enlarge size rather than pixels to start with I have tried multi-focus and let Photoshop merge but with limited success. Reduce the aperture and the slightest spot of dirt is a major problem and unlike the old days of film any dirt on CCD will be on all pictures until next clean.

OK now cameras are well sealed no longer do we see bugs crawling around in the view finder like with early Japanese film cameras but still with super enlargements we have problems much is dependent on where dirt is. In sky area a big problem but in dark areas often we don't notice it exists. I have never removed the lens on my D7000 and I don't intend to the K10D Pentax taught me a lesson the hard way with dirt.

But with a computer screen at 1.47M to view a 14.7M image means one can only view a maximum of 1/10 of the image when checking for flaws in real terms less than that so to check a 25M image before printing is a mammoth job. I printed in college and I was not impressed the getting of the printer and computer screen to show same colours was a real pain even using a colour monkey so many print outs were scrap before we got it correct glad it was not out of my pocket. At £60 each per cartridge and 8 of them with shelf life of 6 months forget that.

So to print only way is to send to a print house I would not print enough to be worth printing at home. So I sit and watch the judge knock marks off for too dark, or too light, or other printing errors and think why do I want other peoples work judged it's my work I want judging not the print houses work. This includes marks knocked off because the mount is wrong colour or badly cut. I would not normally display in a mount I would frame the picture the mount is only to comply with competition rules.

Down side is we are judged on the years work 3 prints and 3 DPI pictures for each competition to decide if we should move from beginners to intermediate, with so many like me not printing, it means there are some really good photographers who will never move up, so beginners is half full of experts, who just don't print, so will never move up.