New lens - quick walk

My new lens arrived a day early, so I thought that I would try it out on the way to the shops.

Both pictures are JPEGs as they came out of the camera.

I like your second shot very much.

I think the 1st one shades it for me.

What lens is it?
I am looking at getting a very wide angle so looking at the results of other
peoples will help me to decide which one to go for.

The two photographs illustrate the two extremes of the lens.

The first one is taken at 10mm and the second one at 17mm.

I like the extreme curviness of the wall in the first one (the lens was effectively sitting on top of the wall) but the second photograph is more "normal".

I am looking forward to when your 10-17 gets an airing

It is the Pentax DA 10-17 (fisheye).

There has been much debate on the forum recently about wide angle lenses and like you I was interested to see the results achieved by other people with various lenses.

I liked the idea of the Pentax 12-24 but it is expensive and 2/3rds of its range is covered by the DA* 16-50.

In the end I like the creative opportunities offered by the fisheye.

Is the CA at 10mm typical for such lenses?

So am I....

I don't feel qualified to comment, having only owned the lens for a few hours.

Perhaps Niblue or other forum members who have owned the lens for a longer time could comment.

Bear in mind that both photographs were taken as JPEG's and have not been tweaked in any way.

I sometimes think that a lot of photographs that we see have started off with all sorts of defects that have all been removed by PS before they are posted.

I'm sure this is true, and I'm not at all criticising the lens (since I'm even less qualified to know how good it is), or your technique.

I'm amazed it's possible to make a 10mm lens at all, considering how far the rear element has to be from the sensor plane, let alone a 10mm zoom, and let alone one that produces results as good as this.

I'm just curious, since with any extreme lens, there have to be compromises, and some CA may be one of the inevitable ones. A bit of PhotoShop admin seems a very small penalty for such a compromise.

To continue to be amazed at how well Pentax zooms are controlling CA and distortion, look again at the 12-24mm and 50-200mm tests and at the new 16-50mm and 50-135mm tests I have mentioned elsewhere.

I'd have to say that's not my experience at all. I can't say I find CA all that big a problem with any lens, however the worst offenders I own are both digital specific Pentax lenses - the DA 16-45 and DA 10-17. It doesn't bother me with either lens, but it's certainly more noticeable with them than with older Pentax lenses or with 3rd party brands like Sigma.

Probably the first thing I noticed with the 10-17 was the CA - this shot was taken the day I received the lens, however please note that it is blown up a little beyond 100%:




I think if I was printing above A4 with either lens I might have to correct the CA, however up to that size it's not intrusive so I don't bother.

From my experience I think Pentax don't mind if a little CA is a side effect of producing lenses with great colour and sharpness (like the 16-45 and 10-17) and I tend to agree with them, however with the 10-20 Sigma have demonstrated that you can have those without CA.

The lenses tested were not the ones you mention, so we're talking about different beasts. All the ones I mentioned have RGB curves that virtually overlay each other, and that's as good as it gets.

I care little for (and trust less) magazine tests.

If we are talking about the type of tests that are really reviews and masquerade as tests, then I wholeheartedly agree.

Happily, the new AP tests to actually go into some sensible detail and back this up with some data in the form of measurements and graphs. Much better than usual and also explained well. Credit where credit is due.

The sister site to this one, Photodo, also has lots of good information, but it does of course need interpreting properly.

Niblue - the example you showed is more "purple fringing" rather than lens-specific CA. I get some PF in certain circumstances on the SMC-F 100/2.8 macro, as well as other lenses.

Wikipedia have some excellent articles on Lens CA and PF (which is still not completely understood!)
Matt