[learnphotography]

Hi fellow Pentaxians,

I have been using the K-x for two months and feel like expanding my hobby. I am deciding on a Tamron 17-50mm F/2.8 and Pentax FA 50mm F/1.4. My main reason of buying a new lens is to have a bigger aperture so that I can do better under low light condition and better sharpness(the kit lens is soft at 18mm and 55mm). Of coz, the two lens above are different.
As in the Tamron, I will get variable focal length from 17-50 which is very flexible like the kit lens. On top of that i get F/2.8.
As in the FA 50mm F/1.4, I get so much more light and supposedly superb sharpness.

Therefore i have done some research on which of these two lens suit me more.
I tend to favour the Tamron 17-50 because of the following:
1. I get 17-50 which is a BIG factor for me as i can take it with me during travel! And FA50mm is fixed at 50mm which mean that i might missed some shot if there condition cannot be control (like taking landscape.
2. F2.8 across all focal length is an improvement over kit lens but not like f1.4 which is super fast
3. The FA50mm F1.4 is very soft at 1.4. Lens's sweet spot (around F2.8-5.6) according to Pentax SMC FA 50mm F1.4 Lens Review: 4. Test results: Digital Photography Review. Which meant that the Tamron is superior as i get 17-50 at the FA50 f2.8

And to add on, how much better is the sharpness of tamron 17-50 against kit lens? A tiny bit?!

[jsherman999]

Tamron 17-50 2.8 is much better than the kit 18-55. Not only do you get much more control over aperture, it's just sharper at every shared aperture, until you get up to f/8 or so, where it's hard to tell the difference. Still, I think the Tamron resolves more, but at f/8, you'd have to crop a bunch to detect that.

The FA 50 1.4 is an incredible lens stopped down to f/2.8, and pretty good down to f/1.4. It probably has the best bokeh of any Pentax 50 save the new DA* 55 1.4.

What I suggest, if you can only afford one right AF lens right now - get the Tamron 17-50 2.8, and then pick up an M 50 f/1.7 ($40-60) or K 55 1.8 ($25-50) and play with manual focus. It's very fun once you get the hang of it, and you'll have both the fast prime and the versatile wide-normal AF zoom. You'll be very happy.

[darrenleow]

Hi fellow Pentaxians,

I have been using the K-x for two months and feel like expanding my hobby. I am deciding on a Tamron 17-50mm F/2.8 and Pentax FA 50mm F/1.4. My main reason of buying a new lens is to have a bigger aperture so that I can do better under low light condition and better sharpness(the kit lens is soft at 18mm and 55mm). Of coz, the two lens above are different.
As in the Tamron, I will get variable focal length from 17-50 which is very flexible like the kit lens. On top of that i get F/2.8.
As in the FA 50mm F/1.4, I get so much more light and supposedly superb sharpness.

Therefore i have done some research on which of these two lens suit me more.
I tend to favour the Tamron 17-50 because of the following:
1. I get 17-50 which is a BIG factor for me as i can take it with me during travel! And FA50mm is fixed at 50mm which mean that i might missed some shot if there condition cannot be control (like taking landscape.
2. F2.8 across all focal length is an improvement over kit lens but not like f1.4 which is super fast
3. The FA50mm F1.4 is very soft at 1.4. Lens's sweet spot (around F2.8-5.6) according to Pentax SMC FA 50mm F1.4 Lens Review: 4. Test results: Digital Photography Review. Which meant that the Tamron is superior as i get 17-50 at the FA50 f2.8

And to add on, how much better is the sharpness of tamron 17-50 against kit lens? A tiny bit?!

I have the Tamron 17-50 and I shoot at f/2.8 very often. However, I've always had to stop down the FA50 to at least f/2 to get acceptable sharpness and depth of field. For me, the decision was between flexibility of focal lengths (from the Tamron) and an extra usable stop of light (from the FA50) and I picked the Tamron and sold the FA50.

[Class A]

I am deciding on a Tamron 17-50mm F/2.8 and Pentax FA 50mm F/1.4. ...
As in the FA 50mm F/1.4, I get so much more light and supposedly superb sharpness.
...
Which meant that the Tamron is superior as i get 17-50 at the FA50 f2.8
...
And to add on, how much better is the sharpness of tamron 17-50 against kit lens? A tiny bit?!

You are right that the FA50/1.4's performance suffers below f/2.8. Some like the soft contrast for portraits but f-ratios between f/1.4 and f/2.8 would be for special purposes.

On the other hand, at f/2.8 the FA50/1.4 will be much better than the Tamron at f/2.8. I don't own the latter and even though I've heard nothing but praise for the lens, a zoom's wide open performance is bound to be worse than a prime which has been stopped down by 2 stops.

The Tamron's problem when compared to the kit lens is that the kit lens isn't a slouch at all. I believe it will be visibly better but you should ask yourself what output sizes you are going to look at. For standard 5x7 prints it won't make a difference which of the two lenses you are going to use (ignoring the Tamron's ability to create shallower DOF).

A criterion you haven't mentioned is bokeh. I'm pretty sure the FA50/1.4 will have an edge here.

Overall, though, it seems that the flexibility of having a zoom seems to be a high priority for you, so unless the things the FA50/1.4 is better at are more important to you, I think the Tamron will be the better choice for you. IQ-wise it is supposed to be really, really good.

Another Tamron zoom that includes the 50mm focal length is the Tamron 28-75 which is a full-frame lens (like the FA50/1.4). If you want to be future proof and don't need the wide angle but could imagine the 50-75 range, e.g., for portraits, that would be another possibility.

[bimjo]

I'd agree with jsherman, start with the Tamron. You can pick up a 50 later.

You might be interested in this thread comparing the FA50/1.4 to a Tamron 17-50/2.8 & a Tamron 28-75/2.8. Pay particular attention to the crops.

The shots are all unsharpened RAW, but they're a good baseline and shots from all three lenses responded very well to sharpening.

[taurus9]

I would recommend to get the MF prime first, and then, if still interested, the 17-50. The M50/1.7 is a very low cost way to test the waters with prime lenses.

Bought the Tamron 17-50 zoom first, and was happy with its performance (except vignetting) and gladly accepted it as an upgrade over the kit lens, once I bought a K55/1.8 prime and mounted it on the Kx, I couldn't believe how much nicer the camera handled over the zoom.

Anyway, something to think about..

[fractal]

The Tamron is a great lens, not just for the price either.

I guess you have to ask yourself, are you going to be shooting in low light and do you favour the size of a prime. Although the Tamron is not very heavy, it is significantly larger than the FA50. Personally though, I could not live without a reasonably fast wide angle.

[rkt]

I would second (... third?) the Tamron 17-50... the 50 should come later ... the 17-50 is sharp and flexible and 'contains' the 50mm mark in it's range. If you find that you love shooting at 50mm then you can later pick the 50 1.4 ... but till then you will have a sharp lens for a useful zoom range. By the way, if you do down the second-hand lens path, I am selling a 17-50 and a M 50 1.7 at the moment...

[anthers]

Another vote for the Tamron 17-50 first, then the 50/1.4 later if you find that you like the 50mm focal length a lot.

[kevinschoenmakers]

Buy the tamron, eat nothing for 2 days, buy an old manual fast fifty for 30 dollars off of eBay

[cezarL]

I'll go against the flow here, and make another recommendation: get a 17-70 instead, and a 50/1.4. The extra 20mm might not seem very important, but the extended range could prove useful. I know quite a few people who moved from the kit lens to the 17-50 and later on to 16-80 (I'm coming from Sony, hence the weird zoom range ).

If money's not an issue, I would recommend the Pentax version, but I suppose a Sigma could work too, if on a tight budget (I do have an aversion towards them, after seeing many reports of stripped AF gear on Sony DSLRs, dunno if that happens on Pentax cameras).

[jimH]

I have the Tamron 17-50 and I shoot at f/2.8 very often. However, I've always had to stop down the FA50 to at least f/2 to get acceptable sharpness and depth of field. For me, the decision was between flexibility of focal lengths (from the Tamron) and an extra usable stop of light (from the FA50) and I picked the Tamron and sold the FA50.

I've got both the Tamron 17-50 F2.8 and the Pentax FA-50 1.4 and both are excellent lenses.

Right now, if I were to buy just one of these lenses I'd get the Tamron 17-50 for every day use. I like landscapes and all around photography and the 17-50 is great for that.

The FA-50 1.4 is great for portraiture and low light indoor photography. But it depends on what you're greatest need is. If it's landscape and general indoor-outdoor photography, then I'd choose the Tamron 17-50.

I bought the Pentax FA-50 F1.4 because it had great reviews, which it deserves, and I wanted to get it before it becomes unavailable in the "new" market. I don't use the FA-50 1.4 nearly as much as the Tamron 17-50, but I'm glad I've got it, and I carry it in my bag.

I'm very impressed with the clarity, contrast and color rendition of the Tamron 17-50. The Pentax FA 50 F1.4 also has good color rendition and clarity at higher f stops, F2 or higher. I'd make my choice on which lens was going to get used the most, but I like both of them myself.

I also have the Tamron 70-200 F 2.8 and in my opinion it doesn't have the contrast, color rendition and clarity or the 17-50 F2.8.

[learnphotography]

Thank You Everybody four the comprehensive recommendation. I will get Tamron 17-50 and then a classic manual focus prime

[Ash]

I also have the Tamron 70-200 F 2.8 and in my opinion it doesn't have the contrast, color rendition and clarity or the 17-50 F2.8.

If that's the case, then the 17-50 must be magic, because my 70-200 is nothing short of brilliant in all aspects.

[kevinschoenmakers]

Thank You Everybody four the comprehensive recommendation. I will get Tamron 17-50 and then a classic manual focus prime

Be aware that M and K lenses require you to press the green button in order to set the exposure. It's a bit of a hassle but not undoable.

In fact, I think getting one of those all-manual primes is the best way to learn photography. Like you, I first bought an entry-level camera with the two kitlenses. I then bought an old fast fifty. All of a sudden I could no longer rely on automation and had to actually think about what I was doing. Also, no zoom means I had to worry about what to include, and what not. Overall, shooting with all-manual primes has been a great lesson.

For more information about the various kinds of Pentax lenses, go here: Pentax K-Mount Lenses Explained