random78

random78

Joined on Jun 3, 2010

Comments

Total: 139, showing: 61 – 80
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On Just posted: Sigma 35mm F1.4 DG HSM lens review article (182 comments in total)
In reply to:

Erik Johansen: For that price it should got a 100% score.......

Ahhh. I must admit I interpreted Erik's post the same way as Clint did. Looked to me that Erik is saying that "such an expensive lens should have been good enough to get a 100% score". But from your comment it seems Erik meant to say that "considering the high performance this lens is achieving at such a low price, dpreview should have given it a 100%".

Direct link | Posted on Dec 21, 2012 at 19:28 UTC
On Just posted: Sigma 35mm F1.4 DG HSM lens review article (182 comments in total)
In reply to:

gsum: I'm a bit surprised to see so much CA in the real world examples in such an expensive lens, particularly at this focal length. Also, DPReview, why the excessive sharpening?

A D800e would have given this lens a better real world test as there would be no anti-alias smearing.

CA is common with all ultra-fast lenses including much more expensive lenses like Cnaon 85mm 1.2L. Remember ultra-fast lenses push the optics to the limit and do suffer from such compromises. Sigma actually does better than many other fast lenses.

Direct link | Posted on Dec 21, 2012 at 18:47 UTC
On Just posted: Sigma 35mm F1.4 DG HSM lens review article (182 comments in total)
In reply to:

facedodge: If it weren't for the onion bokeh, this would beat the 35L.

The reason you never noticed it in the 35L is that in most cases it won't be visible unless you look at your image at 100%. Unless you have some lights which take up an unusually large portion of your image frame, you just won't see it in normal viewing. So yeah might be a serious issue for some but nothing to worry about as far as I am concerned. A 35mm 1.4 lens is an extreme design and always requires compromises. You will never find any 35mm 1.4 lens which will be perfect without any flaw. Based on the reviews so far, the Sigma is as close to perfect as have been seen for a 35mm 1.4 lens so far. So you can either choose to worry about a problem which may have no practical concern for you in your photography or enjoy a great lens.

Direct link | Posted on Dec 21, 2012 at 18:34 UTC
On Just posted: Sigma 35mm F1.4 DG HSM lens review article (182 comments in total)
In reply to:

Ivan Lietaert: "a top notch fast 35mm autofocus prime without breaking the bank"
Priced £900, the author obviously must be making a fortune writing for DPreview! This lens is priced at a working man's monthly income. I wouldn't call that cheap! Please think twice before you write this kind of thing!

Quality photography gear is expensive and you have to look at the price in that context. Compared to the Canon/Nikon/Sony versions at $1500-1600 and the Zeiss at $1800, the Sigma at $900 is surely a much more affordable option.

Direct link | Posted on Dec 21, 2012 at 18:25 UTC
In reply to:

Entropius: There are a lot more things to a lens's performance than a one-dimensional measurement. What does this scheme make of a lens like the Panasonic 14/2.5, which is extremely sharp but has high chromatic aberration? What about the Canon 70-200/2.8 mk1 at 200/2.8, which has poor microcontrast but resolves a good amount of detail? The high sharpness and resolution, but bizarre bokeh, of the Zuiko 50-200?

What about a classic lens like my Olympus OM 50/1.8, which is surprisingly highly-resolving wide open in the middle of the frame (great for portraits) but without the high acutance of modern asphericals, and with a strong dropoff in sharpness toward the edge?

There's a whole lot more to a lens's performance than one number. That's why the old DPReview lens reviews were great, with the little checkerboards: you can see for yourself what the point spread function at different places in the frame is.

> It's a weighted average across the field for the "best" aperture.

Right. And for a zoom lens it is at whichever arbitrary focal length + aperture combination gave the best result for that lens. So a lens gets good score because at some particular combination of focal length and aperture, using some specific unknown weighting of center and corner sharpness it performs well . I wonder how could you consider it a useful measure despite the comparison being so arbitrary. As an example under this measure Canon 24-105mm f4 and Canon 18-55mm IS II have the same P-MPix Score on a 7D.

Direct link | Posted on Dec 18, 2012 at 09:46 UTC
In reply to:

Erik Magnuson: I think this score will correlate pretty well with lens sharpness in general, i.e. a lens with a P-Mpix 15 (of 18) will be noticeably better than a lens with a score of 8. However, it may not correlate as well for small differences, e.g. a score of 14 and a score of 15 may mean lenses that merely have different strengths (i.e. center vs. edge, best vs. wide open performance) where the weighting used does not match the user preference.

If a user merely wants to know "what's an excellent vs. merely good lens", then this number will be useful. Buying the lens with the highest number is rarely going to be "wrong" but it may not be optimal. If you want to know "what the best lens for 35mm f/2 corner to corner" then this number will not be as useful. Digging down into the detail graphs may help, but if you have specific questions you should not expect average numbers to be the answer. Also remember YMMV so small differences in measurements may not be significant in field use.

And I disagree with every site that does that :) including dpreview's percentage scores for cameras which I think are even more useless than DxoMark's scores. If I am lazy when reading say dpreview or photozone, I just read their conclusion paragraphs, but not the scores which can be safely ignored. Also with dpreviw and photozone the score comes at the end after the whole review, as sort of a summary. DxoMark on the other hand emphasizes its scores and de-emphasizes the detailed results which this score is based on. Also by the way not every website does that - for example imaging resource, dcresource or steves-digicams do not have any scores for cameras, even though these websites do a lot more point and shoot reviews as well. Similarly lenstips or slrgear do not have any lens scores. They expect their readers to read the review not reduce the whole review into one meaningless number.

Direct link | Posted on Dec 18, 2012 at 02:24 UTC
In reply to:

Erik Magnuson: I think this score will correlate pretty well with lens sharpness in general, i.e. a lens with a P-Mpix 15 (of 18) will be noticeably better than a lens with a score of 8. However, it may not correlate as well for small differences, e.g. a score of 14 and a score of 15 may mean lenses that merely have different strengths (i.e. center vs. edge, best vs. wide open performance) where the weighting used does not match the user preference.

If a user merely wants to know "what's an excellent vs. merely good lens", then this number will be useful. Buying the lens with the highest number is rarely going to be "wrong" but it may not be optimal. If you want to know "what the best lens for 35mm f/2 corner to corner" then this number will not be as useful. Digging down into the detail graphs may help, but if you have specific questions you should not expect average numbers to be the answer. Also remember YMMV so small differences in measurements may not be significant in field use.

> "And what happens when they do this? They get a good lens"

They can also be paying a lot more than needed just to get a lens which "scores" better, even though for their uses it might not even be the better lens.

>Can you suggest anything better that lazy users should use as a guide?

What Entropius said - don't be lazy. I don't think promoting laziness by making it easy to make misinformed decisions is a good idea. We have already seen this with DxoMark sensor scores where people on forums talk about one sensor being rubbish because it is 10 points lower than the other one on DxoMark, even though looking at the detailed graphs tells a very different story. The issue with "scores" is that you always want the one with the highest "score" and feel dissatisfied with anything with lower score. Whereas by looking at detailed reviews you actually understand which product better meets your needs.

Direct link | Posted on Dec 18, 2012 at 01:42 UTC
In reply to:

Erik Magnuson: I think this score will correlate pretty well with lens sharpness in general, i.e. a lens with a P-Mpix 15 (of 18) will be noticeably better than a lens with a score of 8. However, it may not correlate as well for small differences, e.g. a score of 14 and a score of 15 may mean lenses that merely have different strengths (i.e. center vs. edge, best vs. wide open performance) where the weighting used does not match the user preference.

If a user merely wants to know "what's an excellent vs. merely good lens", then this number will be useful. Buying the lens with the highest number is rarely going to be "wrong" but it may not be optimal. If you want to know "what the best lens for 35mm f/2 corner to corner" then this number will not be as useful. Digging down into the detail graphs may help, but if you have specific questions you should not expect average numbers to be the answer. Also remember YMMV so small differences in measurements may not be significant in field use.

"Digging down into the detail graphs may help, but if you have specific questions you should not expect average numbers to be the answer"

That is true for those users who already understand about the detailed data available. However most new users will just look at the score and use that as the yardstick of which lens is "better". People like ratings because life is much simpler if someone could tell you that thing X is superior than thing Y. Unfortunately once such ratings are in place, most people just use them without realizing how they are just an arbitrary mix of a larger number of detailed parameters. In reality comparing lenses requires looking at many factors and in my opinion it is better if the users are exposed directly to all of them so that they know that it is not a simple question of which one is better. By feeding a single number you give the false impression that somehow this one number is encapsulating the overall goodness of a lens versus the other.

Direct link | Posted on Dec 17, 2012 at 23:04 UTC

Sigh. DxoMark's insistence on hiding lots of useful data behind much less useful "scores" is frustrating. I understand that they want to make it easy for average non-tech consumer who may not be willing to look at all the graphs and resolution maps etc. However in an attempt to do so they give this false impression that a single number somehow can give an accurate impression of the relative performance of two lenses (or sensors). It just cannot and they risk misleading and confusing the users.

Direct link | Posted on Dec 17, 2012 at 18:49 UTC as 73rd comment | 1 reply
On Fujifilm X-E1 preview extended article (113 comments in total)
In reply to:

vroger1: If you are speaking about "Panasonic"- their lenses are magnificent. Idon't just mean their Leica branded lenses. They as always are superb. The Lumix lenses themselves are beyond belief. Their 45-200 (90-400 efl) is too sharp for the average portrait. What the FZ200 has, however, is that constant f 2.8 aperture. I feel now that I can sit at a coffeehouse, and image people at other tables in available light, without too much noise at 1600 ISO from a distance, and avoid their movement blur which drives ma crazy. The average zoom, which closes down at longer focal lengths - always made this difficult.

I don't quite agree to this notion. Whatever is the price of the SW correction, it is reflected in the final result. If the final result from a SW corrected lens is better than the final result from the optically corrected lens then it is a better lens in my opinion.

Direct link | Posted on Dec 12, 2012 at 02:21 UTC
In reply to:

cosmo13: So where is the mast with the camera? I see nothing attached to the Rover extending out of the frame to the camera position. In other words there is nothing going from where the camera must be to the Rover.

I was wondering the same thing. But I think what has happened is that the image has been stitched in a way that the arm has been removed from the picture.

Direct link | Posted on Nov 2, 2012 at 19:17 UTC
On Samsung NX 12-24mm to cost $600, 45mm F1.8 around $300 article (119 comments in total)
In reply to:

the reason: what the hell am i supposed to do with a 67.5mm lens??? Canon Nikon, Pentax, and samsung dont seem to get it, if you have an APS C sensor you should make APS C lenses. Fuji gets it, the upcoming 56.5mm comes to 85mm f1.4, a classic portrait lens. Even m4/3s gets it with the upcoming 42.5mm f1.2 (coming to 85mm), and every lens they make comes to a classic focal length . Heck, even the nikon 1 system has an upcoming 32.5mm f1.2 that comes to 85mm.
Just drop the system already and be done with it, stop half assing it

Keep in mind that samsung already has a 60mm lens i.e. 90mm equivalent, so that focal length is already there. They also have an 85m 1.4 which is a great portrait lens (like 135mm f2 on FF, which is my favorite portrait focal length). The point of the 45mm 1.8 is to have a telephoto option which is fast yet small. Fast telephoto lenses for APS-C are going to be big as seen from the 60mm and 85mm NX lenses. m43 does better at small telephoto lenses but even there the 75mm 1.8 lens is a very large lens. But people look for small lenses to go with their small mirror-less cameras. So 45mm 1.8 is a compromise - a lens for those who want to stick to small lenses but still want telephoto capability.

Samsung has one of the better lens lineups in the mirror-less world, though m43 certainly does better for obvious reasons. But Samsung does much better than say Sony. And their lens FL's are for APS-C - for example the first lens that the released for NX was 30mm f2 - a perfect APS-C normal

Direct link | Posted on Oct 26, 2012 at 00:15 UTC
On Samsung NX 12-24mm to cost $600, 45mm F1.8 around $300 article (119 comments in total)
In reply to:

nawknai: Best lens lineup by far.

I don't get it. Are there cameras just that bad that they don't even get a mention in the EVIL/CSC race? All you hear about are m4/3, NEX, and Fuji, even here. I just bought a Fuji X-Pro 1, but if Samsung had better reviews (and I could find them at a local shop), I would have certainly taken a look at Samsung.

Their cameras are actually pretty good. I currently have a NEX-5N as well as the Samsung NX200 and have used multiple m43 bodies. I like the NX200 controls and ergonomics better than both NEX-5N as well as the m43 bodies that I had. I think Samsung is bad at creating hype and indeed marketing in general. Their cameras are just plain good imaging devices. No retro styling like Olympus, no "slim and stylish" designs like Sony, no "world's fastest AF", or the "best video implementation" etc. Plus in the first generation they were held back also by the noisy sensor. Though this generation has fixed that. My NX200 sensor is fairly close to the 5N sensor and probably better than the Canon APS-C sensors that I have used in the past.

Direct link | Posted on Oct 25, 2012 at 22:31 UTC

And what will they call the next standard - ultra-super-duper-high-definition? I think sticking to 4K is a better idea.

Direct link | Posted on Oct 19, 2012 at 23:12 UTC as 21st comment
On Just Posted: Canon EOS 650D / EOS Rebel T4i review article (232 comments in total)
In reply to:

random78: Does this review including the AF comparison for video mode that was in progress. I quickly skimmed through but didn't see it. Though I might not have looked hard enough

Zooming has its own set of problems even if we take AF out of the picture. Unless you have power zoom like camcorders or P&S cameras, the jerks that you get while zooming via the zoom ring are more objectionable than the slow AF shift.

Direct link | Posted on Aug 20, 2012 at 22:34 UTC
On Just Posted: Canon EOS 650D / EOS Rebel T4i review article (232 comments in total)
In reply to:

random78: Does this review including the AF comparison for video mode that was in progress. I quickly skimmed through but didn't see it. Though I might not have looked hard enough

Thanks! will wait for that. And yeah I saw the comments on video AF in movie section. Looks like it is pretty bad. Based on what you have seen so far, would you say it is even worse than the CDAF based tacking video AF in G5 etc?

Direct link | Posted on Aug 20, 2012 at 20:26 UTC
On Just Posted: Canon EOS 650D / EOS Rebel T4i review article (232 comments in total)

Does this review including the AF comparison for video mode that was in progress. I quickly skimmed through but didn't see it. Though I might not have looked hard enough

Direct link | Posted on Aug 20, 2012 at 19:30 UTC as 75th comment | 7 replies
In reply to:

Gothmoth: canon has already a few new patents up it´s sleeve.
it´s new technology.. it needs time to mature.

i remember the horrible AF on my Olympus E-PL1... what a useless crap that AF was.
2 models later the E-PL3 autofocus is nice.

but one thing panasonic and olympus can not change in their m43 cameras is the smaller sensor... FAIL.

Canon APS-C has only a marginally bigger sensor compared to m43. The difference is fairly small. Based on sensor size you would expect canon aps- to have half a stop of advantage over m43. So given equally good technology canon aps-c at ISO1200 should match m43 at ISO800. And thats just about what you get in G5 vs canon aps-c (the older 12MP m43 sensor was pretty bad though).

However canon is no longer the top of the line in sensor tech so whatever little advantage should be there is lost due to the superior sony tech used in E-M5. E-M5 m43 sensor matches and in some aspects exceeds the canon aps-c sensors.

Direct link | Posted on Aug 16, 2012 at 19:20 UTC
In reply to:

Simon97: Looking at the RAWs, they are better than the 4/3rds cameras and a bit behind the NEX in the comparison. It makes me wonder why the jpegs look like a crappy P&S at higher ISOs. If it has NR control, turn it way down.

peevee1, please point me to this objective testing. I haven't seen any objective testing which supports what you are saying. I have no brand loyalty and have used pretty much all camera brands. And I still use multiple brands so I actually tend to be fairly objective in my assessments.

Direct link | Posted on Aug 16, 2012 at 18:44 UTC
In reply to:

Simon97: Looking at the RAWs, they are better than the 4/3rds cameras and a bit behind the NEX in the comparison. It makes me wonder why the jpegs look like a crappy P&S at higher ISOs. If it has NR control, turn it way down.

Esa - I am comparing to NEX-5N and E-M5 not to some 5 years old sensors. I have also compared the RAW files from dpreview and imaging-resource and they match my own experience. The studio scenes are useful for controlled testing however actual use in a variety of conditions tells a lot which you don't see from studio shots. Its ironic you think you can tell more about a camera by looking at online samples rather than actually using it :) Don't tell me that you know more about these cameras without using them than I know after using them extensively.

Direct link | Posted on Aug 16, 2012 at 18:40 UTC
Total: 139, showing: 61 – 80
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