Software corrected lenses a trend?

bdery · 07-22-2021, 05:26 AM

Originally posted by Rondec

I wonder if there was copy issue here because ephotozine tested it on an RP and said there was about 1.6 EVs of vignetting at 24mm and f4. Unless they did the test on jpegs I have no idea what would give such a huge discrepancy. Canon RF 24-105mm f/4-7.1 IS STM Review - Performance | ePHOTOzine

OpticalLimits are generally quite thorough, and have been known to send lenses back when they observed decentering or other problems. It's unlikely they just claimed such results without verifying their results.

Then again, with such huge numbers...

house · 07-22-2021, 05:35 AM

Opticallimits and lenstip looks at actual raw files using dcraw or other software that allows user control. Most other "reviewers" use adobe and are oblivious to forced corrections with that software.

Those using Adobe will report vignetting and distortion as seen after forced base correction and often think the additional correction available is equivalent to ticking the same box for a Pentax lens despite the latter not having any out of the box corrections applied.

**UncleVanya** · 07-22-2021, 05:45 AM

Originally posted by house

Opticallimits and lenstip looks at actual raw files using dcraw or other software that allows user control. Most other "reviewers" use adobe and are oblivious to forced corrections with that software.

Those using Adobe will report vignetting and distortion as seen after forced base correction and often think the additional correction available is equivalent to ticking the same box for a Pentax lens despite the latter not having any out of the box corrections applied.

Oddly even the “corrected” output numbers from the two don’t match. Very strange.

**Rondec** · 07-22-2021, 06:17 AM

Originally posted by house

Opticallimits and lenstip looks at actual raw files using dcraw or other software that allows user control. Most other "reviewers" use adobe and are oblivious to forced corrections with that software.

Those using Adobe will report vignetting and distortion as seen after forced base correction and often think the additional correction available is equivalent to ticking the same box for a Pentax lens despite the latter not having any out of the box corrections applied.

But 12 EV of vignetting is not correctable. It just has to be cropped out. Maybe that is true in Lightroom -- you just never see the true corners at 24mm because the software forces the correction.

house · 07-22-2021, 07:09 AM

Originally posted by Rondec

But 12 EV of vignetting is not correctable. It just has to be cropped out. Maybe that is true in Lightroom -- you just never see the true corners at 24mm because the software forces the correction.

Thats it. You will never see those corners.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Wide-angle lenses which are well corrected for coma	Bertrand3000	Pentax SLR Lens Discussion	27	12-01-2020 11:44 PM
CIPA April 2020: trend continues	beholder3	Photographic Industry and Professionals	5	06-03-2020 08:39 PM
Nature Mi-Wuk Village - Corrected Shots	ginnyfoos	Post Your Photos!	2	12-23-2019 09:46 AM
Disturbing trend - giving up all rights to photos!	UncleVanya	Photographic Industry and Professionals	45	05-21-2019 06:46 PM
Lenses with Pentax Mount that are Fast, Well-Corrected, and Sharp Wide-Open	MichaelErlewine	Pentax K-1 & K-1 II	17	06-08-2016 05:43 PM

07-22-2021, 05:26 AM	#76
bdery Pentaxian Join Date: Mar 2008 Location: Quebec city, Canada Photos: Gallery Posts: 9,072	Originally posted by Rondec I wonder if there was copy issue here because ephotozine tested it on an RP and said there was about 1.6 EVs of vignetting at 24mm and f4. Unless they did the test on jpegs I have no idea what would give such a huge discrepancy. Canon RF 24-105mm f/4-7.1 IS STM Review - Performance \| ePHOTOzine OpticalLimits are generally quite thorough, and have been known to send lenses back when they observed decentering or other problems. It's unlikely they just claimed such results without verifying their results. Then again, with such huge numbers...

07-22-2021, 05:35 AM	#77
house Pentaxian Join Date: May 2015 Photos: Albums Posts: 2,995	Opticallimits and lenstip looks at actual raw files using dcraw or other software that allows user control. Most other "reviewers" use adobe and are oblivious to forced corrections with that software. Those using Adobe will report vignetting and distortion as seen after forced base correction and often think the additional correction available is equivalent to ticking the same box for a Pentax lens despite the latter not having any out of the box corrections applied.

07-22-2021, 05:45 AM	#78
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 24,775	Originally posted by house Opticallimits and lenstip looks at actual raw files using dcraw or other software that allows user control. Most other "reviewers" use adobe and are oblivious to forced corrections with that software. Those using Adobe will report vignetting and distortion as seen after forced base correction and often think the additional correction available is equivalent to ticking the same box for a Pentax lens despite the latter not having any out of the box corrections applied. Oddly even the “corrected” output numbers from the two don’t match. Very strange.

07-22-2021, 06:17 AM	#79
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 26,046	Originally posted by house Opticallimits and lenstip looks at actual raw files using dcraw or other software that allows user control. Most other "reviewers" use adobe and are oblivious to forced corrections with that software. Those using Adobe will report vignetting and distortion as seen after forced base correction and often think the additional correction available is equivalent to ticking the same box for a Pentax lens despite the latter not having any out of the box corrections applied. But 12 EV of vignetting is not correctable. It just has to be cropped out. Maybe that is true in Lightroom -- you just never see the true corners at 24mm because the software forces the correction.

07-22-2021, 07:09 AM	#80
house Pentaxian Join Date: May 2015 Photos: Albums Posts: 2,995	Originally posted by Rondec But 12 EV of vignetting is not correctable. It just has to be cropped out. Maybe that is true in Lightroom -- you just never see the true corners at 24mm because the software forces the correction. Thats it. You will never see those corners.

Thread Tools	Search this Thread
	Search this Thread: Advanced Search