[msharma]

I am very new to SLR photography. What is the weakness of an 18-150mm lens compared to a 55-300mm lens? I mean if they are made by same standards, is there an inherent disadvantage in 18-250mm? Thanks,

[hcc]

These lenses are different and have different purposes. A direct comparison might be difficult.

The 18-250mm is an all-around lens, that is well-regarded among all brand.

The 18-250mm is however a different lens from the 50-300mm. The main point with the 55-300mm is the need for another lens to cover the same wide range, hence of lens swapping. Otherwise it is well liked by many Pentaxians with excellent user reviews in this forum.


The latest DXOMarks (lab results from DXO) gave the following overall scores for the all-around lenses:
DA18-250mm = 10
Canon 18-200mm IS = 6
Niikon 18-200mm VR = 7
Sigma 18-250mm HSM OS = 8
Pentax 50-300mm = 5
Pentax 50-200mm = 4

These results must be considered with care since they are somehow surprising for the 50-300mm. (I am sure that some DA50-300mm owner will jump at the score...)

Hope that the comment will help....

[sterretje]

Is 10 better or worth than 4 ? I guess better reading your last statement

[hcc]

Is 10 better or worth than 4 ? I guess better reading your last statement

Yes: you may read more at DxOMark - DxOMark Score.

[msharma]

Thanks for the info. It seems Tamron 28-300mm (on Canon) has even higher score. Also, on the comparison tool, the 18-250mm has better resolution than 55-300mm, and is worse/equal in everything else. DxOMark - Compare lenses I guess, it is not unsafe to buy 55-300mm lens (except for need to change lenses).

[Jodokast96]

It would probably help if you at least compared the Tamron with a comparable body, and not a Canon 1D. Score drops considerably when you do.

[Eruditass]

There is more to lenses than resolution, CA, distortion, and vignetting, which is what DxO appears to base their scores on.

Most people prefer the 55-300mm greatly to the 18-250mm in the longer ranges and site such things as colors, rendering, bokeh, microcontrast, etc.

[Cannikin]

Those same DXO rankings rate the DA* 16-50 at 8, worse than the 18-250, and just barely above the kit lens (worse than Canon kit lens).

Those scores are worthless.

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Last edited by Cannikin; 11-27-2010 at 02:21 AM.

[Rondec]

I wouldn't depend on those scores to make a decision, particularly since I have no idea what factors go in to add up to 10 or whatever number appears. The 18-250 is a "super-zoom" which means that it covers nearly all of the focal lengths that you would standardly use. It will be a little soft in spots and have some distortion at the wide end, but if you want one lens that you can use 95 percent of the time, without changing lenses, this is probably it. On the other hand, the 55-300 is a telephoto lens. It has a little wider aperture throughout its range (stays f4.5 to 200mm) and will be a little sharper throughout its range as well. It would complement the kit lens pretty well or any other "normal" zoom lens that you might get.

My personal preference is to stay away from super zooms, but they certainly can produce great results.

[steve1307]

I have both, I got the 55-300 new late last year and a used 18-250 form the marketplace here. I get more use out of the 55-300 as I usually take it and a couple of primes.

Comparing the 2 in the 18-54 range no contest obviously, and likewise in the 251-300 range.

Throughout the common range the 55-300 is about 1/2 to 1 stop faster. Which is an advantage.

I notice the difference from the 18-250 and 18-55 at wide open. The 18-250 is really dark in the corners and the distortion is pretty bad.
I try to use it just off the fully wide length (say at about 21-24mm.... but it drops to f4 by then)

A lot of people say that the 18-250 is great until about 135 and then kind of drops off after that. My copy at least seems pretty good nearly to 250 if at f8 in the centre at least.

At the edges the DA55-300 seems better. (I dont shoot brick walls or newspaper pages, and could only find a couple of shots I took where I could notice any difference). In the real world I doubt it make much differnce.


I think the Purple fringing is a bit worse on the 18-250, that is to say it is more noticeable with this lens when used at the longer end.


I've never used the 18-250 in poor light conditions (or indoors actually) so I cant comment on that.
Actually i've never used the 55-300 indoors either, which brings me to the only gripe i have with the 55-300. The mimimum focus is about 6 feet and this is sometimes an inconvenience, if you're in a tight spot.
With the 18-250 you can a least get a close focus shot (psuedo macro) of something.

As for comparison of colour & contrast I cant say any difference for certain, I think I have had a polariser on everytime I have used the 18-250. (actually that could be the real reason for the dark corners when i used it at 18mm!)

I will say that neither can match a DA15, DA35 or DA70 for colour, contrast or sharpness. These are the 3 lenses I use most.


Anyway my feeling of the two lenses is that the 18-250 is kind of getting to the absolute limit of its design at it s two ends so I try to avoid using it there.

The 55-300 feels like it has a safety margin so I'm happy to use it wide open f4 at 55 and also all the way to 300mm.

There is one more thing, zoom c-r-e-e-p on the 18-250 (on my one at least) is horrendus, but at least the lock is conveniently located.


If you're only going to carry 1 lens ---- 18-250.

When going out with my 55-300 I always have to take something wider too.

[newarts]

How a long lens performs wide open is important to me & often under-emphasized in reviews.

Shooting with a hand-held long lens often requires as much light as possible to avoid motion blur. The fact that a 200mm lens might be fantastic at f8 doesn't help when trying to get a picture of an on-stage performer from the 8th row or a woodpecker in the dark forest! In such cases sharpness wide open is highly important to me & stopped-down performance is secondary or unimportant.

Dave

PS the parameter to minimize is (acceptable_F-stop_squared) times focal length; ie decreasing the acceptable f-stop by 2 allows 4 times the focal length for hand-held work.