[Aloïs]

Hello,

I can buy a FA 100-300mm f4.7-5.8 or a FA 100-300mm f4.5-5.6 for just 50 euros, which is better? I don't mind the weight.

Thanks

[jeffrey r]

See

Pentax Lens Review and Specification Database - 100-300mm F4.5-5.6

and

Pentax Lens Review and Specification Database - 100-300mm F4.7-5.8

Seems the 4.7-5.8 is the better lens.

[RioRico]

I have the f/4.7-5.8 version (US$120 on eBay last year) and I'm astounded by its image quality. Just a few minutes ago I finished a rough test shoot of it vs a number of manual 180-200-240-300 primes, and the Vivitar Series 1 Version 1 70-210 classic zoom. I haven't reviewed the shoot yet, but in previous comparisons with the Super-Takumar 200/4 and Tele-Takumar 200/5.6 it ranked right alongside those gems. I don't usually shoot birds (or care to) but my best bird shots have been with this lens.

Reading the user reviews linked above, you'll see that about the only complaints are that it isn't silent, and it isn't black. It looks cheezy on my black K20D. It looks fine on my black-and-silver SX-M. I don't care what it looks like. It's lightweight and the optics are great. I also recently did a rough test of it with the Sigma 170-500/5-6.3 APO and it's damn difficult to tell them apart within their common range. The FA weighs 380g. The Sigma weighs 1270g. Guess which I carry more often?

[Aloïs]

Thank you for your answers,
so the silver lens seems to be the best choice.
I'm a little disappointed, because the other lens is heavier, well built and color is black !

Anyway the most important for me is image quality. So I think I will buy the silver lens.

I could find some photos at full size of the black lens on Flickr, not so sharp at 300mm, but I couldn't compare them with the silver lens.

Did anyone compare together these lenses ?

[Eruditass]

Had there been any comparisons with the f4.7 and the current telezooms (Sigma/Tamron 70-300mm)?

[bdery]

I also own the f4.7. you can read my review in the database.

The one thing I find hard is to handhold shots in medium-to-low light at 300 mm. This focal length increases the visible effect of camera shake by a tremendous amount.

The lens is not as contrasty as my former Vivitar series 1 70-210 but it's quite sharp, extremely so when used well, and it's reliable.

I'd like it to be faster at the tele end, of course, but it's not a pro lens, after all. And the silver actually draws a few interested/envious looks from some people (mostly Canon users with kit lenses).