47greyfox Loc: on the edge of the Colorado front range

This is a question of whether I should be concerned or not. In a couple months, the wife and I will be taking a Rhine River cruise and I'm entertaining the idea of bringing a single lens instead of an armful. I looked at the Tamron 16-300mm F/3.5-6.3 Di II VC PZD Macro today. I read in a review where some "expert" thought it had excessive barrel distortion at the low end of the zoom (if that's the right expression). So I took the below shot with the lens on a Canon 70d standing relatively close to a brick wall. I then took the resulting image and loaded it into PSE 11, did distortion repair and nothing else. Bottom line, I am looking for opinions on whether the amount of distortion on the image is acceptable or not? Is the correction in PSE 11 about what I should expect and do you believe that to also be acceptable? I figure acceptable distortion is one of those "in the eyes of the beholder" things, and I sort of think it's significant but at the same time would like to hear whether hoggers think I'm over reacting. Thx!!

Native JPEG - 16mm, f/11, 1/2500 sec, ISO 640

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Native after PSE 11 Distortion Correction

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speters Loc: Grangeville/Idaho

I don't know if it is acceptable, only you can decide, but if it shows this much after correction, it sure is significant!

47greyfox Loc: on the edge of the Colorado front range

I kind of thought so, as well. But, I'd be the first to admit that I didn't take a lot of time in the PSE correction module. Very possible that more could be done, and I didn't have enough time with the lens to see at what focal length did the distortion pretty much disappeared. After your comment, I pulled the "corrected" image back into PSE and tried more correction. Unfortunately, movement in one direction seemed to cause problems in another.

oldtigger Loc: Roanoke Virginia-USA

looks as though it cleaned up well enough. Noone need ever know you were shooting with one of those all-purpose zoom lenses.

47greyfox Loc: on the edge of the Colorado front range

Here are three more pics that are as shot. As you can see, I really didn't take the time to make sure they were level, I was more interested in the brick line. All shot at f/11 and ISO-640.

16mm 1/640 sec

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52mm 1/400 sec

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185mm 1/400 sec

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TJer Loc: Colorado

If I had to make that decision I'd first ask myself: Was the in camera distortion control features turned on before taking the shot?, Will I be taking any architectural photos where this kind of distortion would be noticed and disliked?, Is this kind of distortion consistent through out the focal range of the lens?, Last but not least, is the lens satisfactory for your other needs? Seeing what I see here, and having looked at some of the test results, I'd probably spend a tad more and get the Nikon equivalent, the Nikkor AF-S DX NIKKOR 18-300mm f/3.5-5.6G ED VR because it seems to have better overall sharpness and consistency through the focal range. No-one can make up your mind for you though. Maybe you can compare another lense like the Tamron you tested and determine if there are differences from one lens to the other. In addition, I'd probably also rent a copy of the Nikon lens to compare with the Tamron using the same camera. Good luck with your decision!

47greyfox Loc: on the edge of the Colorado front range

Thanks. Yeah, my DSLR is a Canon 70d, but your suggestion is a valid one. I was thinking a Canon 18-200mm for comparison. Local camera stores are pretty reasonable about letting customers step outside and shot examples for evaluation. I guess I was just surprised to see the amount of distortion at that focal length.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

PTLens will get rid of all of the distortion if the lens is in his database.

http://epaperpress.com/ptlens/

mcveed Loc: Kelowna, British Columbia (between trips)

So will DXO Optics Pro.

47greyfox Loc: on the edge of the Colorado front range

I downloaded the program. The lens was in his database, but I didn't see much improvement from what PSE was able to give me. I read in the PTLens help section that he will calibrate if he doesn't have a lens but didn't want to see bricks (inherently not perfect) and wanted a minimum of distance from camera to object of about 25 feet. Whereas I was no more than 6-8 feet away from the wall I shot. At that distance, I could have introduced some distortion merely by my camera position relative to the brick wall?

mcveed Loc: Kelowna, British Columbia (between trips)

Of course. At that distance the bricks at 30 degree angle from you are quite a bit further from the lens than the bricks straight ahead. So they will be rendered smaller because they are further away and will result in distortion. In addition to this, the bricks at the bottom of your image, and at the top, are also further away than the bricks straight ahead, so distortion there too. Further, if your camera is not perfectly level, the distortion will be unevenly distributed from top to bottom. At that distance with a 16mm lens it would be a miracle if you didn't get distortion. I think even a flat field lens would show distortion in this situation.

47greyfox Loc: on the edge of the Colorado front range

Yeah, I think you're right mcveed. I need to return to the scene of the crime and try again. Plus, bring my tripod. I kind of messed this up. Great intentions, though!! :-)

shutterbob Loc: Tucson

Don't know how many brick walls you plan to photograph from up close on your trip but I'm betting not many. You are not likely to see much if any distortion in most photos. I have this lens mounted on my Nikon D7100 when I go on trips and don't have the room or need a lot of gear. I love it for this purpose. It is reasonably wide and goes to 450mm equivalent on the cropped frame cameras it was designed for. Not real fast but with most DSLRs doing a good job at higher ISOs that is not usually much of a concern. It also does a reasonable job at macro (about 1:3). And if you do shoot a brick wall, you can correct most of the distortion pp. I have found that my full frame spends more time in the safe at home when I travel since I got this lens. Buy it....I think you will be well pleased.

47greyfox Loc: on the edge of the Colorado front range

Thanks Shutterbob. I returned to the scene of the crime this morning and backed off to 25-30 feet and tried again. The results were much better and what little distortion at 16mm there existed was easily corrected. I'm thinking I'll give it a shot.