[dylansalt]

I was going through lens tests by Popphoto and was amazed to see (according to their MTF Charts) that the 55-300 actually out performs (IQ) the pro 300 f2.8 lens.

Please see attached charts.

My question is;

Is this really a true scenario??

How can this inexpensive lens trash (IQ wise) a Pro lens.

D

Attached Images

   

[Michaelina2]

You might find the answer here:

The Online Photographer: Charts 'n' Graphs

Cheers...

[dylansalt]

Great article.

Unfortunately we all need some objective data to start with before purchasing a new lens.

I know inherently that the 300 will produce excellent IQ and will be the superior lens i.e focussing speed,low light etc

But in terms of the review here the 55-300 will (in pics up to A4) give me the same IQ (relative to my seeing eyes) as the more expensive 300.

Just as much as people owning the 16-50 will say that it gives way better IQ than the kit lens - I simply can't see it in the pictures - thus I would say that the 55-300 must be an incredible little lens for the money (but taking it's known slow auto focusing speed out of the equation)

D

[jslifoaw]

I wouldn't be surprised if they couldn't be picked apart easily for smaller prints as you state. To design a 300mm lens is many orders of magnitude more difficult and expensive at F/2.8 than at F/5.8, which is over 2 stops slower.

That said, the "S" in "SQF" (the type of table those attachment are) stands for "subjective" and it is certainly not an MTF table.

Making conclusions based on one review alone (and then one criterion such as the vacuous term "IQ") is not a great idea although it will certainly make people happier depending on their circumstances (i.e. if a lens they own checks out well!).

I did try the 16-50 and did not like it, with or without a review to affirm or disprove my conclusions.

Great article.

Unfortunately we all need some objective data to start with before purchasing a new lens.

I know inherently that the 300 will produce excellent IQ and will be the superior lens i.e focussing speed,low light etc

But in terms of the review here the 55-300 will (in pics up to A4) give me the same IQ (relative to my seeing eyes) as the more expensive 300.

Just as much as people owning the 16-50 will say that it gives way better IQ than the kit lens - I simply can't see it in the pictures - thus I would say that the 55-300 must be an incredible little lens for the money (but taking it's known slow auto focusing speed out of the equation)

D

[Miserere]

Are you sure you're not talking about the DA* 300mm f/4?

Another thing to take into account that does not appear in these charts is distortion. One reason to favour primes (apart from better performance in low light and expected faster AF) is for the low distortion. Does the subjective quality factor take into account contrast and colour? Were both these lenses subjectively evaluated by the same person?

[Ole]

You may want to check photozone Pentax Lens Tests for more objective data.

They haven't tested the 300/2.8, but they do have the 300/4.5.

No doubt that the 55-300 is a fine lens, but the 300/4.5 is better when you look at all the many parameters tested. Based actual use of my 300/4.5 and a loaner 300/2.8, the latter appears even a notch above the 300/4.5.

[Michaelina2]

You may want to check photozone Pentax Lens Tests for more objective data.

For some odd reason, photozone.de uses the K10D, an out-of-production (and some say obsolete) camera as their reference for Pentax lens testing. Kinda like using your Mom and Dad's 8-track hi-fi as the reference for your new digital player.

The new Sheriff in town is the K20D. Beware of "objective data" delivered from folks who use anything less.

my .02 cent$...

[ghelary]

Photozone.de protocol of testing is coherent. If you want to compare lenses, you have to compare them on the same body. Their idea is to only compare lenses on APSC bodies, and I can't blame them for that.

They have upgraded tests on Canon recently to the 50D, maybe it's safe to expect that they will upgrade to the K30D when it gets out. BTW the only difference that one would expect from the K20D is a better resolution for the best lenses. (From Nyquist theorem, you have to sample at twice the highest frequency here pixels are samples, highest spacial frequency is resolution)

For example, my 31st Limited still outresolves the K20D @ f/8 and in full daylight. So a sensor with much more pixels may show the real limits of the lens. Anyway the conclusions from Photozone are the same that I came to. Photozone tests have limits, yes, but their protocols of testing are consistent enough to give reliable information.

And they don't give 5 stars at every above average lens. So looking at their critics is always a pleasure.

[Fl_Gulfer]

Yep those 2 charts are of the DA 300 f4 and the DA 55-300.

[Bart]

For some odd reason, photozone.de uses the K10D, an out-of-production (and some say obsolete) camera as their reference for Pentax lens testing. Kinda like using your Mom and Dad's 8-track hi-fi as the reference for your new digital player.

The new Sheriff in town is the K20D. Beware of "objective data" delivered from folks who use anything less.

my .02 cent$...

ghelary already explained the validity of the Photozone testing system but I would like to add another point:
I find your bashing of other peoples (Pentax) cameras extremely rude, impolite and behavior unworthy of a Pentax user.
I would suggest you leave this kind of attitude outside of the forum.

[pikipoki]

Threads like these always seem a little weird to me.
If someone asks or claims (after reading a test) that a 300$ lens is better than a 1000$ that just is weird isn't it??

And I have already read a few looooong threads about how the 18-55 kit lens performs as good as the 16-50 or 16-45 or Tamron 17-50...but that is just nonsence.

My 18-55 kit is an OK lens, as cheap as it gets and therefore a good deal, but that's all.
It is a huge difference if a lens is sharp at f2.8 (or f 4 with the 16-45) or if you have to close it to f8 to get acceptable image quality (with the 18-55).
And still the 18-55 at f8 still isn't as sharp as the better lenses at f2.8 or f4.

And I know what the photozone test says about the 18-55 in terms of resolution...I almost fell of the chair as I was reading it...according to the tests it should be as good as the FA limiteds....
So again - nonsence.

I know it doesn't aply to the question asked but I think the relations are the same.

As already said, the 55-300 is a good lens, but not comparable to a DA* 300/4.

My advice: try them all out I see for yourself.

Matej

[Miserere]

Another point to bear in mind: I would expect a prime, especially a DA* prime to be equally sharp across the frame for any aperture, while a consumer zoom will likely be sharper in the centre and fall off towards the edges, except maybe at f/8 or f/11.

As for the K10D being in the same league as 8-tracks...I'd like to ask Michaelina2 to pass it around if he's going to insist on posting high, because unless everyone else is also high his comments aren't going to make any sense. Or maybe it was a joke?

[Syb]

I do not know the 55-300. But I am a big fan of the A*300/2.8

Maybe this is because it cost me my entire savings pig last year,... but I am still happy I bought it.

[hecthetech]

Some comparison test shots:

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/24568-pentax-d...4-5-6-a-5.html

[dylansalt]

Thanks and confirms that the SQF charts attached were accurate

The 55-300 is one cracker zoom lens for the price!

The DA 300 f4 here in SA is 3 times the price of the zoom but doesn't seem to have 3 times the IQ.

sweet

D