Pentax K20D

[alanmcf]

I am getting close to wanting/buying an SLR and am tempted by the Pentax K20D. It is mostly for shooting landscapes at low ISO often on a tripod. The 14.6 meg pix seem like a reasonable match for my 24" printer (the alternative is to wait longer .

Along with a Pentax 18-250 zoom... would my 645 Pentax prime lenses a helpful addition (I am budget consciousness)? Would say the 200mm be noticeably sharper?

Any comments would be appreciated. Thanks, Alan

[Er1kksen]

I am getting close to wanting/buying an SLR and am tempted by the Pentax K20D. It is mostly for shooting landscapes at low ISO often on a tripod. The 14.6 meg pix seem like a reasonable match for my 24" printer (the alternative is to wait longer .

Along with a Pentax 18-250 zoom... would my 645 Pentax prime lenses a helpful addition (I am budget consciousness)? Would say the 200mm be noticeably sharper?

Any comments would be appreciated. Thanks, Alan

I'm planning my own purchase of one of these in the next few months.

To be honest, if your thing is tripod landscapes, I'd skip the 18-250. That's more of an all-in-one travel lens, and there are some compromises on image quality as a result. If you want a normal zoom, I'd go with the 16-45, it's about $100 cheaper and wider and has better performance.

I'm not sure about how your older mf primes will work on the K20D, it's important to remember that they were designed for a much larger format that placed lower demands on its optics than modern high-pixel-density digital sensors do. If I were you I'd be looking at pentax's modern primes, as they are some of the finest optics available for digital SLRs, period. Sadly, they can be a little pricey, with the exception of the old fast fifty and the pancake (41mm, I believe).

[alanmcf]

To be honest, if your thing is tripod landscapes, I'd skip the 18-250. That's more of an all-in-one travel lens, and there are some compromises on image quality as a result. If you want a normal zoom, I'd go with the 16-45, it's about $100 cheaper and wider and has better performance.

Yes, I am pondering which lenses as well. Turns out for landscapes I my favorites are the 35mm equivalent of a 100 and 150. I tend to me most fascinated by zooming into the scene.

I am still curious if anyone has actual experience using 645 primes on an APS sized digital quality wise. On one side these are said to be very high quality lenses and that only the sweet center part would be used (shame they cannot be tilted), and on the other side they had less need to be sharp based on the larger format.

Thanks, Alan

[Dale_Cotton2]

Er1kksen writes:

I'd go with the 16-45, it's about $100 cheaper and wider and has better performance

As a non-tripod, carry-everywhere lens, the 16-45 is just the ticket, and doubtless the 16-45 is better than the 18-250 (although I've never tried it), but the new Pentax 17-70 f/4 seems better still. I'm finding my copy is sharper overall, and much cleaner in the corners. Of course, it's also heavier and more expensive.

[DarkPenguin]

Good lord.  I've nothing to add to the main point of the thread but the K20D seems to be down to $700.  I think I've found a new budget camera to recommend.

[Er1kksen]

Dale, I've been looking at that 17-70, but while the 16-45 reviews seem universally positive, the 17-70 reviews seem to be more of a mixed bag so far. Have you owned both? When using the 17-70, do you miss the 16mm wide-angle? I'd be interested in hearing your experience with the two.

[Dale_Cotton2]

Er1kksen wrote:

Have you owned both? When using the 17-70, do you miss the 16mm wide-angle?

Yes: I bought the 16-45 with the camera then traded up to the 17-70 six months later when the 170-70 became available. I shot a comparison series on tripod at the dealer's before buying. The 17-70 proved obviously better at nearly all focal lengths and apertures. The disappointing aspect of the 17-70 is how soft it gets above 45mm; and of course the reason I was interested in the lens at all was just to add the extra reach without having to swap lenses. So I investigated the lens looking for that extra reach, but ended up buying it more because of its quality in the shorter focal lengths. (Of course I used the K20D's focus correction capability to check for front/back focus error; but that doesn't seem to be an issue.)

Not only have there been formal reviews of the 17-70 on-line, but at least one competent forum member of the Pentax forum on dpreview, posted careful work. Apparently, my copy is better at the tele end than others have seen, which suggests either luck or some initial production problem that was caught and corrected. For all I know, 17-70s on store shelves today may be even better.

The upshot is that we have 3 wide/mid tele options from Pentax:

• 16-45 f/4: light-weight but well-built; significant distortion at edges; my copy, at least, a bit soft at the wide end but otherwise stands up to the K20D's sensor in the usual f/5.6 to f/8 comfort zone.
• 17-70 f/4: hefty and pricey, well-built; extremely low distortion; excellent colour rendition; excellent sharpness from 17 to 50 or so; increasingly soft above 50.
• 16-50 f/2.8: even heftier, weather sealed; presumably excellent optically; AF problem at far tele plagued production for first year but seems to be fixed now. (I've never tested this lens, not needing the speed and not wanting the weight. But an e-mail friend has it and is thoroughly pleased.)

If you want I can put up a handful of the test sequence raw files on my site; but the entire set is 35 files, at 15 to 18 mb each, which seems a bit much. ;)

do you miss the 16mm wide-angle?

Yes, that 1mm makes a more substantial difference in FoV than one would imagine, but I've never yet found myself wanting the extra width in the field, whether landscapes or candids. All that means, though, is that I'm just not an ultra-wide sort of a guy. ;)

[Er1kksen]

Thanks Dale, that was very informative.

Personally, I am a bit of a wide-angle type, and with a budget... it's likely I'm going to skip on the normal zoom alltogether (I never use it with my current gear, I just use my fast prime, my tele, and sometimes slap on the normal zoom to use it at its widest setting) and get the 50mm 1.4 and 50-200 or sigma 70-300 APO to replace my current oly kit, and add the 10-17 for that wide-angle/fisheye I always coveted.

[tetsuo77]

I am getting close to wanting/buying an SLR and am tempted by the Pentax K20D. It is mostly for shooting landscapes at low ISO often on a tripod. The 14.6 meg pix seem like a reasonable match for my 24" printer (the alternative is to wait longer .

Along with a Pentax 18-250 zoom... would my 645 Pentax prime lenses a helpful addition (I am budget consciousness)? Would say the 200mm be noticeably sharper?

Any comments would be appreciated. Thanks, Alan

Yes, they would. Check the dpreview forum for it, there are handful examples of 645 lenses on the K20d.
For the resolution thing you say:
Options that work well in that range format: FA* 85 1.8 [but this is an extremely expensive lens, and not worth compared to the 77].
Over the limited lenses: The 77 is actually a 115.5 mm focal length. It is half a stop faster than the pancake lens, and renders a little bit better.
Cosina-Voightlander 125mm
FA 75-320 4.5-5.6 [yes, very cheap and "bad", but it does hold quite a bit resolution wise. Try it before you buy it, though. Very good microcontrast].


And your medium format lenses. I did actually tried them, and the main difference is not the resolution, it is the difference in character they give [first shocker image you get].
; )