ISO 12233 ISO Crops and lens decisions

[DLS]

Hi all. I am wondering how much stock to put into the ISO crops when it comes to deciding on a lens. I am currently in the market for a landscape lens. For "wide angle" landscape shots I use the wide end of my widest zoom, the 24-105mm. The sweet spot is 35mm @ f/5.6-f/11 (from viewing Bryan's ISO test results) for the wider end. The Canon 16-35 II seems the best bet for Canon wide angle. So how much weight do the ISO tests carry?? Should I be more concerned with real-world photographic examples?

Thanks in advance.

Damian

[Jon Ruyle]

My feeling is that real world examples, while more relevant, are more difficult to judge. Personally, I put a lot of weight in Bryan's ISO tests because in my experience they reflect lens sharpness better than measures I see on other sites. On the other hand, I don't put that much weight in them because most quality lenses are sharp enough for me anyhow, especially when stopped down.

For my money, the 24-105 is pretty sharp- geometry is a bigger issue than sharpness with this lens. The 16-35 is better in this regard at overlapping focal lengths, no question. A high quality prime will do better still.

[Dr Croubie]

Certainly I look at the 12233 crops, but make sure you also read the texts.
I'm not sure how Bryan does his tests, if it's one centre-focussed shot and that's it, or if he focus-brackets and picks the best for each of the 3 crops. Things like field-curvature don't show up in the crops: using the first method it just shows as blurry even though the lens could be sharp on the edge, but closer to the lens; using the second method you get to see the the lens is indeed sharp on the edges, but you may not realise that it's not all in a plane.

Looking at real-life tests in another good thing, the more the better, but as long as you can see it at 100%, you can see the details for the shot (mm, f/, iso, camera, etc). Anyone can make a photo look good at 400x600 pixels, it's the differences in the large-prints that differentiate the good lenses from the rest...

[HDNitehawk]

Hi all. I am wondering how much stock to put into the ISO crops when it comes to deciding on a lens. I am currently in the market for a landscape lens. For "wide angle" landscape shots I use the wide end of my widest zoom, the 24-105mm. The sweet spot is 35mm @ f/5.6-f/11 (from viewing Bryan's ISO test results) for the wider end. The Canon 16-35 II seems the best bet for Canon wide angle. So how much weight do the ISO tests carry?? Should I be more concerned with real-world photographic examples?

Thanks in advance.

Damian

I think you have to do all three and give them all weight.

Look at reviews, I have always found Bryans and accurate. When you read reviews you should always concider if they are bias or not. Bryans reviews never come off as a sales pitch trying to sell you on buying a more expensive lens.

The ISO charts have no bias, for the most part if you look at them carefully side by side you can get a good idea of what to expect.

Third look at examples. Sometimes it is hard to compare sample to sample, the reason is you do not know how much post processing goes on. But if you look at enough you can get an idea. There are certain feels that certain lenses have when they take pictures. One that you hear about all the time are the Zeiss owners. Sure allot of there raves may be pride in paying way to much for a lens, but if you look at some of the pictures they take you can see why they do have some justification in then there pride.

I will add one more to the list, ask the people that own the lenses you are comparing. That might tell you more than all the reading you do.

Personally I put a fair amount of weight in the charts, especially if I am upgrading to a new lens. If the chart doesn't beat the lens you have, you should have no expectation that in the real world you would see any improvement.

Now the lenses you listed these I have owned or own now. I would take the 16-35mm L II over the 24-70mm L or the 24-105mm L any day. At 35mm the 16-35mm is an excellent lens. For IQ I would take the 35mm F1.4L prime over the 16-35mm L II. I would take my 24mm F1.4L II over all of them. Right now I have a 24-70mm L that has not been out of the box in a year. I have a 16-35mm that I have taken out twice in the last year, mainly for video. My 35mm L and 24mm L travel with me all the time.

With the release of the new 35mm Zeiss recently, I have been thinking of giving it a try.

Good Luck

[DLS]

Thanks for your responses guys.
@Jon: I agree, real world examples are difficult to judge - like Dr. C says, pics in print or web look pretty good at low resolutions.
@ Dr. Croubie: I would think Bryan doesn't focus bracket.....wouldn't not-focus-bracketing be more representative of how one would judge real-world sharpness, centre to corners? Or would the characteristics of the scene dictate one's evaluation? As in, if you had foreground subject matter, say, in the lower corners.
@HD: I have spent a lot of time looking at the ISO charts and have corroborated their results when it comes to my 24-105 and 50 1.4. Exactly, if the chart doesn't beat the lens you have, one should have no expectation that real world results would be better. And thanks for your first-hand knowledge. I was considering primes as well but was checking zooms first as I am, at this point in my photographic journey, quite addicted to zooms.

Thanks again guys for your insight. i would much rather take your advice than any one i can think of in my circle.

Damian

ps. Boy that TS-E 35mm II looks good....

[HDNitehawk]

I was considering primes as well but was checking zooms first as I am, at this point in my photographic journey, quite addicted to zooms.

Trust me on this one. Zooms are the cheaper addiction.

The L primes are going to give you better IQ for the most part. But you are going to pay a big premium for just a little bit better IQ. Then it takes you 3 lenses to cover the same range. ....I found that this is one of rules of thirds in photography...to get that next small level jump in IQ, it seems it always costs you 3 times as much as the next level down....

Good Luck
Rick

[DLS]

Trust me on this one. Zooms are the cheaper addiction.

The L primes are going to give you better IQ for the most part. But you are going to pay a big premium for just a little bit better IQ. Then it takes you 3 lenses to cover the same range. ....I found that this is one of rules of thirds in photography...to get that next small level jump in IQ, it seems it always costs you 3 times as much as the next level down....

Good Luck
Rick

I hear you. i know my 50 f/1.4 @ f/5.6 is killer (i think). Its the multiple-primes-to-cover-said-range that keeps me from seriously going after it....that and the fact that if I did, I would have to toilet train my newborn daughter....hmmmm. Maybe I should wait.

Truthfully, i'm very very happy with my 24-105 for my needs right now. There's just been a few instances where I would have loved to use 24mm but was not willing to sacrifice IQ as compared to that lens at 35mm...

Thanks Rick.

Damian.

[DavidEccleston]

Bryan does extensive work for this ISO chart shots, definitely not a single shot and post it deal.

Read about it here.

[DLS]

Bryan does extensive work for this ISO chart shots, definitely not a single shot and post it deal.

Read about it here.

Thanks for the link David.

Cheers

Damian

[Rocco]

Damian,

I guess I'll just say that for starters, I'm no expert on the subject. But here is my opinion on the charts.

For sure, ISO charts are a big part of it.. but not really the only thing that makes a lens IMO. Take the 50mm f/1.2 for example.. While Bryan does say that it has " the best image quality they (you) can get from f/1.2 to f/2", he also talks about how sharpness isn't everything, speaking about the color and contrast and flare control. The ISO charts make this lens look sloppy like a pig stopped down, even compared to the nifty fifty. (I guess that lens could be another example, super sharp but not always a desirable real world result.) But when I go through the flickr group photos for the 1.2, I just don't see it. I see amazing images.. and the lens is on my wish list.

Me, I read his reviews first, then I take a look at the charts if I'm really curious.. but I rarely put a ton of weight behind my decision based on that alone.

I guess ISO charts are helpful, but you still have to consider contrast, color, aperture, IS, build quality. For some ISO is a big piece of the puzzle though.