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Ade-oh
02-26-2008, 07:33
This is the first photography forum I've ever been a member of and one of the things that has surprised me is how often people seem to shoot 'lens tests'. I have to say that this is something I've never done. The only obviously bad lens I've ever owned was a secondhand Olympus OM Zuiko 35-105 zoom which was always soft and vignetted at the wider end, so I took it back to the shop where I bought it and got my money back. So the question is: do you shoot lens tests?

I'd also be interested to hear why.

Anupam
02-26-2008, 07:38
When I get a new RF lens, I do a ground glass focus accuracy test, but when I shoot film it is always real world shots, not test shots.

charjohncarter
02-26-2008, 07:50
I do shoot my sons wallpaper sometimes to check for edge sharpness, but I have to agree with 'sitemistic' I can never see much difference in newer lenses. When something isn't right with a photo it is usually me that caused it.

Roger Hicks
02-26-2008, 08:15
Well, I do, but then, I'm paid to.

Increasingly, though, I focus on handling, feel, character and what it can do, rather than on test targets. As everyone else has said, you should be able to take most of this for granted.

What I want to read in a lens test is what I'd like to hear if I asked a friend, whose opinion I respected, "What's it like?"

Cheers,

R.

like2fiddle
02-26-2008, 08:24
When I buy a "new to me" RF lens, I like to see how it behaves under different conditions, so yes, I usually do a test of some sort. This usually involves trying it with and without a hood, shooting into light, different apertures, etc.

mfogiel
02-26-2008, 08:25
One of the things I've learned by now, is to make a test of accurate focusing on the body of choice - if in doubt a focus shift test across the apertures doesn't harm too. Once you know you can focus with confidence, the rest is done by shooting several rolls in "field" conditions.

jolefler
02-26-2008, 08:35
I'm testing, shimming, testing, unshimming, reshimming, testing :bang: . I put general shots on the same roll as tests, though. Some actually work out...thanks to DOF at f11-22 :)

I've never tested my Leitz lenses, seems they shoot just fine from my general work.

Jo

Graham Line
02-26-2008, 08:53
With a new lens, I generally shoot a roll in familiar places -- where I know what to expect -- just to get an idea of the depth, edges, shadow quality and so on. But I rarely take notes and it isn't very rigorous testing.
The last time around, with a new 35, plus a 28, 40 and 50 at various times, it was very hard to tell which was which from the final set of negs -- which was good.

williams473
02-26-2008, 08:53
Nope, don't shoot official lens tests, although like everyone probably does, I carefully evaluate my first few rolls from a new camera/lens until I trust it is giving me good images.

I have to say however, I do appreciate it when people who are more technical than me post lens tests online - I usually get over-obsessed by lens sharpness, so if I can find someone who has tested a lens I use, I'll gladly take the time to read it.

Matthew Allen
02-26-2008, 09:28
It depends what you mean by lens test. With digital I fire off a few frames of whatever object I'm standing near when I get a new lens but I've never bothered with rigorous testing, especially not with film.

That said, if I were buying a lens with known sample variation issues (like a Sigma or certain Tamrons) I might be more cautious. Although with modern manufacturing it's not generally a problem, some low-end lenses have an alarming rate of centering defects.

Matthew

WoolenMammoth
02-26-2008, 09:37
most of the lenses I buy are 40 years old. Its a little foolish to not test something that old. Every lens I get I'll do a focus test just to make sure the body I have it on can actually focus it... I work in an industry however where that is totally the standard thing you do on the first day at work, so its hard to imagine not doing it with unknown equipment. I suppose it just comes down to how important the work is that you are shooting. Wether its formally understood as such or not, the first roll you put through any unknown equipment is a defacto test at the end of the day. Id rather have a crummy roll of focus charts to throw away rather than a roll I shot for a client...

icebear
02-26-2008, 11:15
??? What's a lens test :confused: - just kidding, but no I don't do shots of walls or wallpaper or newspaper stuck on the wall etc. I haven't bought anything that would require a lens test to make sure I don't have a bad one - and currently I hope I'm done...but one the other hand CV1.4/35, you never know....maybe for X-mas:cool: .

raid
02-26-2008, 12:24
I have done lens testing for the fun of doing such tests with many lenses contributed by RFF members. It is especially fun and interesting when exotic lenses that also are vintage are included in such a test.

Example: Compare Nikkor 50mm/1.1 to Canon 50mm/0.95 and Leica 50mm/1.0.

This are great lenses to try out.

bmattock
02-26-2008, 12:35
I don't take anything at face value, so if I buy a lens (always used, me=cheap), I test it against a lens of a known (to me) quality.

I will set up a tripod and control for as many variables as I can, and then scan the results and see where/what the truth is - for me, anyway.

This helps me determine things that are hard to pin down, such as the lens' 'sweet spot' or best f-stop to use for maximum sharpness. It tells me what the bokeh looks like wide-open. If there is a tendency to lens flare, I may see that as well. And finally, if there is any otherwise undefinable 'quality' or 'signature' to the lens that others wax poetic about but cannot seem to describe in literal terms, I see that as well.

Conclusions - no magical lenses. Most of them are very good performers under real-world conditions, and without access to high-end tools and an optical lab, spending a huge amount on glass doesn't make a lot of sense - to me, and for my purposes, anyway.

However, I've found some lenses that *do* stand out head and shoulders above others.

Number one - the Pentax Super-Multi-Takumar 50mm f/1.4 in M42 mount. That lens is a killer. Nothing else I've ever tried even comes close for sharpness at every aperture. Granted, I don't have access to Canon "L" glass and other lenses made of unaffordium.

Another lens that blows me away - the Pentax non-SMCF 70~210 f/4 zoom. I love the lens at about 90mm and f/4 on a digital SLR for environmental portraits from about 20 feet away - stunning.

And I often joke about it, but the Sears 135mm f/2.8 Macro lens, in PKA mount, made in Korea, is excellent even wide-open (to my eyes). Goes for less than $20 new in the box as old stock.

Others are less stellar, not quite 'knock your socks off' but I still find them excellent for the money, like the Canon 50mm f/1.4 (black) LTM mount lens and my A. Schacht Travenar series LTM lenses from 35mm to 135mm.

The Agfa Karat IV 50mm f/2 Solagon lens (unfortunately a fixed-lens rangefinder) has a quality that is breathtaking wide-open, a real pity it is not removable.

I would not know these things if I did not try them against each other in a reasonably controlled environment. Nothing I see online convinces me like seeing it with my own eyes.

raid
02-26-2008, 14:01
The Canon 50/1.2L and 85mm/1.2L are very sharp lenses. I agree with you that the Pentax SMC 50/1.4 is a killer lens when it comes to sharpness. Other "super" lenses that I have are the Nikkor 55mm/3.5 micro and the Canon 50mm/3.5 macro and the Pentax 50mm/4 macro. The Canon 80-200/4L is amazing.

I bought these lenses based on online comments/reviews about them.

Brian Sweeney
02-26-2008, 14:20
I'm a hobbyist, buy lenses, hack them, and always test them. I've sold quite a few of them, often "on request".

If you are going to adapt a Zeiss Tessar made in M42 mount for an SLR to be RF coupled on a Leica, I highly suggest testing it.

Gabriel M.A.
02-26-2008, 15:25
This is the first photography forum I've ever been a member of and one of the things that has surprised me is how often people seem to shoot 'lens tests'.
Do you not take a newly purchased car for a test drive? Do you not smell a bottle of cologne before buying it, or do you buy it, spray it on and hope for the best?

I also test any new headphones, 'cause I like to hear my favorite music well. But anybody with a tin ear wouldn't care and it'll all be the same to them.

I guess that's why you test things, to see if they're good.

Roger Hicks
02-27-2008, 00:29
I guess that's why you test things, to see if they're good.
Yes, but there's a big difference between testing something to see if it does what you want, i.e. taking pictures with it (which you can hardly avoid doing); testing resolution, distortion, etc., with test charts; and obsessively comparing it with another lens you own.

Most amateur 'tests' are appallingly badly designed anyway -- colour neg film, commercial processing, scanner -- whereas if you are going to do it properly you need consistently processed film (and always the same film), a microscope for examining sharpness (and grain, in film tests -- and a photomicrographic outfit so you can compare pics rather than trying to remember which looks grainier), a shutter speed tester for leaf shutter lenses... As for comparing actual apertures with marked, this is REALLY difficult.

A thourough test like Raid's is one thing, but most people's 'tests' are so casual that they tell you next to nothing that you could not learn from taking pictures.

Then there is the informal testing that most of us, surely, do when we first get a lens: a wall or other straight line near the edge to check for distortion, twigs or telephone wires against the sky for flare, maybe even an informal vignetting test at full aperture (sky, white wall, whatever). With half a dozen shots or fewer we can see if there are any nasty surprises; we don't need much more.

Cheers,

Roger

projectbluebird
02-27-2008, 01:42
I don't shoot lens tests, but I test my lenses... if that makes sense.

Whenever I get a new (to me) lens, I'll shoot with it for awhile. So I can get an idea of it's handling, abilities, "fingerprint" etc. But I don't stick it on a tripod and shoot a wall because A) I don't own a tripod, and never use one. And B) How often do you really take a picture of a brick wall?

I prefer to see how my lens performs under actual use. Typically I shoot under widely varying conditions, this usually gives me a fairly good idea of what a lens can or cannot do, under a range of apertures and lighting. But I don't shoot test targets or setups, I don't particularly care about lpm or MTF curves. (blashphemy I know) If I like what I see, I'll keep the lens. I very rarely sell (or buy) a lens, but there's always a reason.

Some of this indifference is because most of the lenses I own are usually decades old, even if I went to the trouble of tracking down contemporary lens reports, my particular lens may have aged to a different condition. That said, looking at actual photos made with a lens I'm interested in can be very informative, the test shots by Raid and others are particularly handy in this regard.

Ade-oh
02-27-2008, 02:02
Do you not take a newly purchased car for a test drive? Do you not smell a bottle of cologne before buying it, or do you buy it, spray it on and hope for the best?

In the sense that I go out and use a lens then of course I test it, but what I don't do is 'test' things like edge sharpness, distortion and so on. If the pictures look OK, then that's fine by me and most of them have. As I mentioned above, over 30 years or so of taking photographs, I've only bought one lens that obviously wasn't fit for purpose (I suspect it was faulty rather than bad design) but that was clear from simply taking normal pictures. I generally try to avoid using lenses wide open, unless I'm looking for a specific effect, and my experience has been that once you get around f5.6-f8, it's pretty much impossible to tell different lenses of similar focal length apart.

Roger Hicks
02-27-2008, 02:50
In the sense that I go out and use a lens then of course I test it, but what I don't do is 'test' things like edge sharpness, distortion . . . once you get around f5.6-f8, it's pretty much impossible to tell different lenses of similar focal length apart.
I shoot a fair number of buildings, inside and out, so distortion matters to me if there is a straight wall near the side of the picture; so I make a deliberate attempt, early on, to include such a shot, which otherwise might not come up for several rolls. Of course most manufacturers publish this data, so if I already know, there's no need to check.

I'd agree about the f/5.6 thing EXCEPT for older, cheaper reverse-telephoto wide-angles and zooms, where distortion is often horrible at all apertures and resolution may still be improving beyond f/8 or even f/11.

Contrast also varies quite widely, along with its cousin, flare.

Cheers,

Roger

naren
02-27-2008, 02:52
In the past the only "test" I've done was comparing the 2 versions of the Nikkor 35mm PC (perspective control) lens I have, using digital capture. Both were reputed to be of excellent quality, the later one was said to be the sharpest Nikkor 35mm lens at f/2.8. I saw no difference but I'm pretty sure that's because the digital sensor captured only the middle part of the image. I'm going to repeat the test on B&W film along with 3 other Nikkor 35mm lenses I have now.

I've been buying a lot of old equipment lately for shooting a documentary type project (and my God those prices!) So I've picked up a few duplicates, etc. I think you are trying to figure out what makes sense for you? And probably you are curious as well about hoopla on the boards. I am testing partly to satisfy my curiosity but mostly in order to do my best as a professional photographer. I think it is important not to waste your time and to consider in your testing - 1. What you are doing makes sense scientifically. 2. It makes sense in practical terms. For me if I know that I'm going to get a sharper image with my 35mm f1.4 and I know I am printing scenes with lots of detail at 11x14in for display, then after having done the tests I know it's worth toting the lens. If I am shooting flash, and I know that my 35mm f2.5 will give me just as good or close enough sharpness by whatever f-stop- I can take my much lighter lens. Heck I might even sell the f/1.4 based on these tests (I don't like the focusing action anyway). I've read over a number of times lens tests by Bjørn Rørslett (I like the info he gives and his style) and people who do that kind of testing are invaluable to pros who haven't had the chance or won't in order to find out themselves. Some photogs who aren't very technical will say, whatever, I'm using Nikkors or it's all good modern glass. I think the more you know in this Ultra-competitive field the better off you are. So you can consider also what the gentlemen says below but you don't have to test exactly as he says to learn what you want to know. Nothing wrong with printing 11x14's, use the same enlarger, etc.


Most amateur 'tests' are appallingly badly designed anyway -- colour neg film, commercial processing, scanner -- whereas if you are going to do it properly you need consistently processed film (and always the same film), a microscope for examining sharpness (and grain, in film tests -- and a photomicrographic outfit so you can compare pics rather than trying to remember which looks grainier), a shutter speed tester for leaf shutter lenses... As for comparing actual apertures with marked, this is REALLY difficult.


The following statement I don't agree with at all-
I generally try to avoid using lenses wide open, unless I'm looking for a specific effect, and my experience has been that once you get around f5.6-f8, it's pretty much impossible to tell different lenses of similar focal length apart.

Although I may avoid shooting wide open in many situations if you do read the tests people have done, some lenses are very sharp wide open. Most tests will describe some softening or minor loss of contrast if it's a good lens- but some also say "snappy" even wide open. It pays to know these things. As far as being able to tell different lenses apart at 5.6... I bet you can see a noticeable difference in quite a few lenses of a given focal length. I think with 35mm film the difference becomes noticeable at about an 8x10 print or 8X. I've seen shows with 16x20s from 35mm, and that guy knew a thing or too I'm sure about sharp lenses. I am very curious to see the diffence in my 11x14s between the Nikkor 24mm f/2.8 I just picked up (another great eBay score!) and the Zeiss ZF 25mm f/2.8 if I have get the dough for that lens. That will put a considerable difference in published lens test results into "real world" terms for me. I was holding out for the Zeiss lens because that was pretty much the last prime lens missing from my Nikkor line up and although it was a landmark lens, the 24mm Nikkor has not been reported to be stellar. The sample I got is gorgeous though. It has a the old hill and dale focusing collar I prefer and the Ai "kit" (if anyone can explain the details of those I would much appreciate) and a buttery focusing action.:)

Ade-oh
02-27-2008, 03:29
As far as being able to tell different lenses apart at 5.6... I bet you can see a noticeable difference in quite a few lenses of a given focal length. I think with 35mm film the difference becomes noticeable at about an 8x10 print or 8X. I've seen shows with 16x20s from 35mm, and that guy knew a thing or too I'm sure about sharp lenses.

Fair enough: I'll take a closer look to see if I can 'spot the difference'. I suppose in reality I rarely print much larger than 10x8 in 35mm and, in any case, there's the issue of the enlarging lens which comes into play then which presumably may be adding some distortion all on its ownsome.

Contrast also varies quite widely, along with its cousin, flare.

True, though I think I would bundle these in as part of the 'character' of a lens and work around it in normal use.

raid
02-27-2008, 16:55
Yes, but there's a big difference between testing something to see if it does what you want, i.e. taking pictures with it (which you can hardly avoid doing); testing resolution, distortion, etc., with test charts; and obsessively comparing it with another lens you own.

Most amateur 'tests' are appallingly badly designed anyway -- colour neg film, commercial processing, scanner -- whereas if you are going to do it properly you need consistently processed film (and always the same film), a microscope for examining sharpness (and grain, in film tests -- and a photomicrographic outfit so you can compare pics rather than trying to remember which looks grainier), a shutter speed tester for leaf shutter lenses... As for comparing actual apertures with marked, this is REALLY difficult.

A thourough test like Raid's is one thing, but most people's 'tests' are so casual that they tell you next to nothing that you could not learn from taking pictures.

Then there is the informal testing that most of us, surely, do when we first get a lens: a wall or other straight line near the edge to check for distortion, twigs or telephone wires against the sky for flare, maybe even an informal vignetting test at full aperture (sky, white wall, whatever). With half a dozen shots or fewer we can see if there are any nasty surprises; we don't need much more.

Cheers,

Roger

Hello Roger,

I did my lens comparisons with a lot of caution, knowing the missing elements of a professionally designed and excuted lens test. I simply do not have the time and energy to do what you described above as being necessary steps in a valid lens test. I still believe that my comparisons of lenses gave some useful results for the potential user of the lenses that were included in my tests.

same film
same developing
same subject
same light
use of tripod
use of cable release
replicate photos


Roland's efforts [Thanks!] in taking my images and creating with enlargements a higher level of comparisons made the last battery of 35mm-40mm lens testing more useful. We covered:

sharpness
flare control
bokeh
contrast

In the end, it all was a lot of fun.

Thanks for the heads up. :)

Dektol Dan
02-27-2008, 19:07
Yes, but there's a big difference between testing something to see if it does what you want, i.e. taking pictures with it (which you can hardly avoid doing); testing resolution, distortion, etc., with test charts; and obsessively comparing it with another lens you own.

Most amateur 'tests' are appallingly badly designed anyway -- colour neg film, commercial processing, scanner -- whereas if you are going to do it properly you need consistently processed film (and always the same film), a microscope for examining sharpness (and grain, in film tests -- and a photomicrographic outfit so you can compare pics rather than trying to remember which looks grainier), a shutter speed tester for leaf shutter lenses... As for comparing actual apertures with marked, this is REALLY difficult.

A thourough test like Raid's is one thing, but most people's 'tests' are so casual that they tell you next to nothing that you could not learn from taking pictures.

Then there is the informal testing that most of us, surely, do when we first get a lens: a wall or other straight line near the edge to check for distortion, twigs or telephone wires against the sky for flare, maybe even an informal vignetting test at full aperture (sky, white wall, whatever). With half a dozen shots or fewer we can see if there are any nasty surprises; we don't need much more.

Cheers,

Roger

Shots at test patterns? Oh please! Thank God my tests are so amateurish! Good lenses have a 'look' a 'personality', it takes a professional to nurse a lens to its best and edit the results for others to to see without bias as presented in the photographs themselves. However, experience cannot be separated from opinion in these matters, not everyone can afford to play with the best, or the most rare and unique.

There is much more to a lens than lines per inch and believe me, 4000 DPI scans reveal far more than any loop. What is wrong with using negative scans for God's sake? I can't even follow that one! There isn't a color positive film made that can match the latest black and white negatives and besides when is god enough good enough? Color aberration and comas can be seen quite well from scans of negative film, thank you. When is grain apparent? Why at 2800 DPI. We are doing far better than that nowadays.

There is no one catch all lens test. I look at many images on Flickr, so far that is my best measure: pictures from the real world: real day to day use.

Roger Hicks
02-28-2008, 02:08
I did my lens comparisons with a lot of caution, knowing the missing elements of a professionally designed and excuted lens test...
Dear Raid,

Sorry if I created the wrong inpression. I meant specifically that your tests WERE well designed, unlike most -- which you have just confirmed.

Cheers,

Roger

Roger Hicks
02-28-2008, 02:12
Shots at test patterns? Oh please!
Consider what I do for a living, and what magazine editors (used to) want to publish. Note also that I said MICROSCOPE, not loupe.

Cheers,

R.

raid
02-28-2008, 09:25
Dear Raid,

Sorry if I created the wrong inpression. I meant specifically that your tests WERE well designed, unlike most -- which you have just confirmed.

Cheers,

Roger


Hello Roger,
I understood your initial comment, and that's why I thanked you for the heads up. I can see the need for additional testing methods when comparing new lenses. It seems that almost all new lenses are fine performers for general applications.

Roger Hicks
02-28-2008, 14:10
. It seems that almost all new lenses are fine performers for general applications.
Dear Raid,

No disagreement there (except zooms).

That's why I think that 'objective/subjective' well-controlled comparisons like yours are so valuable.

The only caveat is that in magazines we say, "Trust what we say, not the pictures, because of the limits of photomechanical reproduction."

On the web, I'd trust what you say (based on direct comparisons of original pics) well ahead of what I see (on-screen images).

On this occasion, "you" means "Raid", not "one" (as in "one learns that") or "other testers".

Glad there was no misunderstanding. I'm almost tempted to write, "Respect!"

Cheers,

R.

raid
02-28-2008, 18:45
Dear Raid,

No disagreement there (except zooms).

That's why I think that 'objective/subjective' well-controlled comparisons like yours are so valuable.

The only caveat is that in magazines we say, "Trust what we say, not the pictures, because of the limits of photomechanical reproduction."

On the web, I'd trust what you say (based on direct comparisons of original pics) well ahead of what I see (on-screen images).

On this occasion, "you" means "Raid", not "one" (as in "one learns that") or "other testers".

Glad there was no misunderstanding. I'm almost tempted to write, "Respect!"

Cheers,

R.

Hello Roger,
Thanks again for your words.
I value your experienced input here.

Cheers,
Raid

Tom A
02-28-2008, 19:04
I dont "test" a new lens. I usually take it out with my regular film and a camera that I know is correct as to focus/speeds etc. I shot a batch of film with it (usually 5 rolls) over a period, Sometimes in one day and sometimes in a couple of days. If it is a lens with a focallengths that is close to one that I already have - a second body with a "known"lens will provide a "reference" point. My shooting is as per usual - a rather aimless wandering around with a couple of "set shots", the trees down at the beach, the stainless steel sculpture at the museum and the laboriously engraved poem about rain in Vancouver on arock on one of the beach walks.
This will tell me how the lens will perform in my type of shooting and that is all I am really interested in.
Years ago I used to shoot industrial stuff. It was paramount that straight lines were rendered straight and that colors were true and I did all the McBeth colorcharts, the US Ar Force resolution tests and focus checks that I ever wanted to do.
The amazing thing with todays optics are that they are really very, very good and that doesn't mean that only the expensive ones are good, some of the low or medium cost lenses today are quite spectacular performance wise.
Ergonomics, build quality, size and weight are more deciding factors today. I have the luxury that I dont have to deal with an editor or a client anymore and what I do I do for my own pleasure.
As I was reading this I tried to recall what bad lenses i have used over the last decade or so. Surprisingly few!! I had "dud" 35/1,4 Asph Summilux, an old 50/1,4 Nikkor with a misaligned element and there might have been more, but none springs to mind (a couple of russian 50's maybe).
As for lower cost "gems", the original 25/4 Snap Shot Skopar, the 28f3.5 Color Skopar. Midrange ones. The 25/35/50 (both 1.5 and f2 of the 50's) ZM line and then of course the expensive ones, the 50f1.4 Asph Summilux, the 75/2 Summicron, the 18f4 Distagon ZM and the 35mm f1.2 Nokton.
I have said if before and I will say it again. As rangefinder users, we have never had it this good! Unfortunately, neither can we blame our equipment either when the shot doesn't measure up!

raid
02-28-2008, 19:44
I own only one CV lens that I bought because I was curious about "that new lens line" a few years ago; it is the old style 25mm/4 Snap Shot Skopar. It really is a gem, as Tom states above.

some examples:
http://i162.photobucket.com/albums/t261/raidamin/549569-R1-16-15A.jpg
http://i162.photobucket.com/albums/t261/raidamin/549569-R1-13-12A.jpg
http://i162.photobucket.com/albums/t261/raidamin/549569-R1-15-14A.jpg
http://i162.photobucket.com/albums/t261/raidamin/549569-R1-12-11A.jpg

Hacker
02-29-2008, 00:02
Do you not take a newly purchased car for a test drive? Do you not smell a bottle of cologne before buying it, or do you buy it, spray it on and hope for the best?

No, and yes, I still have lenses that I have not shot with yet :(. I do, however, once in a while, shoot at the closest distance and at infinity to satisfy myself just before using the lens on a shoot.

I guess I have no pressure to have the shots perfect as I'm only an occasional photographer.

Toby
02-29-2008, 04:11
I always run a test roll through the camera, just to check everything is working OK, but I'm a portrait photographer so edge sharpnes isn't so important, most of what I look for in a lens is subjective - do I like it rather than technical specs. I love the old 105 SMC takumar I have for my pentax 67, but I doubt it's a very good lens in tests.