Decent lens?

[Johnboy2978]

Came across this Tamron lens that I was going to use with my new Pentax IST. Can anyone tell me if this is worth buying or not?

http://www.bhphotovideo.com/bnh/con...ail&Q=&sku=213162&is=REG&si=acc#goto_itemInfo

Being new to the film cameras, what should I look for in quality lenses? I don't understand the group and elements, but it seems that is one of the more essential characteristics when comparing lenses, right? Can someone give me a brief edification?

Thanks for responses.

 

[Big Mike]

It looks to be an OK telephoto zoom lens. Comparable to Canon or Nikon 75-300 entry level Telephoto zooms.

You may find it a little slow at F 4.0-5.6, though.

I don't know much about groups & elements when it comes to lens design but a simple indicator of quality is usually price.

Typically, more expensive zoom lenses have better build quality and better auto focus. What really drives up the price is the speed (maximum aperture) of the lens.

Prime (non-zoom) lenses are less complicated to make/design than zoom lenses...so you can usually get more quality for your money.

 

[Canon Fan]

My good friend has one of those and what I can tell you is that they feel cheap, look cheap and act cheap. Not bad pics but the plastic seems to give up quickly. The zoom and focus on his is really stiff and sticks, and he only has maybe 900 exposures on it TOPS! Like I said though the pic quality is acceptable for an all around everyday sorta begining piece of glass.

 

[ksmattfish]

I don't understand the group and elements, but it seems that is one of the more essential characteristics when comparing lenses, right?

If you are a lens designer, then "groups and elements" are important. If you are just a lens user, then don't worry about it. It's mostly just another number for the salespeople to baffle you with.

Once upon a time more lens elements, and complicated design meant higher quality; for instance an anastigmat lens design has 3 elements, a tessar design has 4 elements, and a planar design has 5 or 6 elements. These days any zoom is going to be a fairly complicated design, on the other hand the 5 or 6 element planar design from 50 years ago is still considered a top performing design. I'll take the planar on my Rollei up against any lens that says Nikon or Canon, and crush them :twisted:

Used properly, almost any modern lens, even the cheaper consumer models, are cabable of very good quality images. The plastic body helps reduce cost and weight, which may be two very important aspects with amateur photogs. I've used plastic body lenses with out babying them for years, and they've held up for me.

 

[DocFrankenstein]

If you are worrying about the quality, you can always get this one:

http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=70002&is=REG
http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=148577&is=USA

It's worth the money... I have the sigma. You may not be ready for those price tags obviously.

 

[Johnboy2978]

nope, don't have that kind of disposable income right now. Just wanted something that I could use to play around with on the new camera. I have an old mf zoom lens but since it isn't af, when I attach it to the pentax IST, I am not able to get any aperture values (think you can with custom settings, but haven't gotten that far in the manual yet). Anyway, my wife was wanting something with AF, b/c she has some vision problems telling exactly what is focused or not through the old MF lens.
At the same time, I don't want a hunk of junk. I'd rather spend $300 on one decent lens than $100 each on 3 crappy ones. I guess I should have been able to decide by the price, but lots of times you are paying for the name and not necessarily reciprocal in quality. Being new to the camera hobby, I am still too green to know how much to spend on a middle of the road lens.

 

[Big Mike]

As with most hobbies, you will find many ways to spend your money

You will find that $300 is the low end of the scale when it comes to AF lenses. You can still get great images with a $300 lens but once you try a $1000 lens, or a $4000 lens...you will understand the difference.