[Clavius]

I've been searching high and low for good recent Pentax MTF charts, but It's near impossible to find these. Does anybody have a good source? I've already tried Photozone.de, but the MTF data and reviews are ancient.

To be more specific: I'm trying to decide if I should sell of my Pentax SMC DA 35mm macro ltd limited to replace it with the Pentax SMC D-FA 100 macro. Sharpness is the most important factor here. But if I read the MTF charts on photozone correctly, this move would actually be a resolution-downgrade. Dang! This doesn't comply withe more subjective reviews of both lenses here on PF, which seem to favor the 100mm.

Pentax SMC DFA 100 macro: Pentax SMC-D FA 100mm f/2.8 macro - Review / Test Report - Analysis

Pentax SMC DA 35 macro ltd: Pentax SMC DA 35mm f/2.8 Limited macro - Review / Test Report - Analysis

So if anybody can shed some light on this, that would be a great help!

[Wild Mark]

these two lenses offer completely different macro shooting experiences. What are you going to shoot regularly - static objects with no fear of a lens (go with the 35mm) or flighty scared critters (go for the 100mm)

[Clavius]

these two lenses offer completely different macro shooting experiences. What are you going to shoot regularly - static objects with no fear of a lens (go with the 35mm) or flighty scared critters (go for the 100mm)

I know the 100mm will be much better at not-scaring little critters. This is an added benefit for me. But I'd much rather risk (maybe) scaring off a critter, then trading in a lens with excellent sharpness for one with a tad bit less sharpness.

But macro-capability and shooting critters isn't even all that important. I just want an ultra-sharp lens; a feature that's often found in macro lenses.

[Wild Mark]

I use both and see no discernible difference. 100mm is FF

[Clavius]

I use both and see no discernible difference. 100mm is FF

That's good news. If I had my way, I'd just add the 100mm to my arsenal and keep both. But prior experiences with heavy LBA has forced me to keep myself to a maximum number of lenses. So, now I need to sell one to buy one. Therefore, it needs to be an upgrade. FF-capability sure is a big plus for the 100mm.

But if anyone has a good source for Pentax MTF data, please let me know.

[starbase218]

Pentax lenses seem to be reviewed less and less. The last lenses Photozone reviewed were the DFA 50 macro and DA 16-85, but these were reviewed on a K-5 II, which is also not current anymore. Here, Klaus mentions he would do 3 more lens reviews after the 16-85. One of these was the DFA 50 macro, but it seems the others have never taken place.

[BigMackCam]

I know this doesn't answer what you're asking, but as Wild Mark says, these lenses give very different shooting experiences. I'm not a dedicated macro shooter, but with the DA35 f/2.8 I've always found it works best for general use and "close-up" as opposed to macro (or what I think of as macro). It gets very close to things, whereas the DFA100 seems to leap right in there amongst what you're shooting. Of course, it has general applications too - it's nice for portraits, especially head and shoulders - but, for me, it's versatility is in macro, whereas the DA35 f/2.8's versatility is as an all-rounder, with great close-focusing. I don't study MTF charts for the lenses I use, other than to get an indication of where each one peaks for centre and border resolution, but speaking subjectively I am always astounded by the detail from the DFA100...

[Clavius]

I do love the versatility of the 35 macro though!

Another reason for wanting a 'sharper' lens is the fact that I don't find (my copy of) the 35mm all that sharp. I don't know how to describe it. But the problem is most prominent when I'm using it in my studio. The more flashes, the more obvious the problem becomes. You know how some lenses have this blue hotspot in the center? Well it's like my DA 35 has the blue hotspot all across the frame. I'll post two pictures tonight when I get home for comparison, one with the 35 and one with another lens that's set to 35mm.

So, maybe I'm better off replacing my SMC DA 35 ltd by a HD DA 35 ltd for its superior coatings?

[BigMackCam]

That's strange... I don't think the HD coatings would make that much difference... I assume you're shooting with the hood? Do you have a filter of any sort fitted? I understand the "blue hotspot" might be caused by reflections between two lens elements or by something between the aperture and the sensor (or film plane) - not sure if that's true, but I've read about it. I've not experienced any hotspots or generalised tint on my DA35 f/2.8 photos... but I've never looked for them, either. If I get time, I'll try some shots in the garden today in bright sunlight.

[UncleVanya]

DXO has info on both lenses on more modern bodies. By their measure on the k-3 the DA 35 is rated 13 for sharpness and the DFA 100 is rated 10. The DFA 50 is rated 12 and is full frame and might be a nice compromise if the focal length appeals to you.

Sharpness is over rated.

[BigMackCam]

Wilfried - I just took a quick test shot with the DA35 f/2.8 - camera pointing in direction of sun (though the sun is high at the moment), with a UV filter on the lens and hood retracted (so, really, not a great scenario). I noticed no "hotspots" or any problem with sharpness (though your expectations may be higher than mine!). My DA35 is the HD version...

First shot below is the whole resized image; the second is a 1:1 crop from the centre...

EDIT: The images look sharper when viewed natively on my PC - the uploaded versions suffer from softness introduced by file compression.

[Digitalis]

From my lens tests with the D-FA100mm f/2.8 Vs DA 35mm f/2.8 the longer lens would indeed be a downgrade in terms of resolution. Klaus does a good job with his tests and his figures from his resolution tests are very close to mine. To be honest, if you're looking for a high performance macro lens, you're going to have to suck it up and get a FA*200mm f/4 ED Macro.


Pentax K10D - SMCP-FA*200mm f/4 ED Macro 1/500th ISO100 f/5.6

[Clavius]

Hi Guys,

As promised, here's a sample of what my copy of the 35 ltd macro produces with a comparison: (fyi, it's my old broken K5, which I haven't been able to throw away yet...)

Pentax SMC DA 35mm macro ltd:


Pentax SMC DA 18-135:


Both lenses mounted on the same body. (K5IIs) Both used with hood, both at F5.6, same lighting, etc...

Wilfried - I just took a quick test shot with the DA35 f/2.8 - camera pointing in direction of sun (though the sun is high at the moment), with a UV filter on the lens and hood retracted (so, really, not a great scenario). I noticed no "hotspots" or any problem with sharpness (though your expectations may be higher than mine!). My DA35 is the HD version...

First shot below is the whole resized image; the second is a 1:1 crop from the centre...

EDIT: The images look sharper when viewed natively on my PC - the uploaded versions suffer from softness introduced by file compression.

Many thanks for doing that for me. Looking at your pictures, I'm beginning to think there's something seriously wrong with my copy. I've started browsing through my pictures, and 5 years ago, the pictures from my copy were as crisp and clean as yours. So somehow, through the years, it has degraded somehow.

Sharpness is over rated.

I'm going to have to disagree with you. Or at least say that lack of sharpness is an issue.

[Adam]

I do love the versatility of the 35 macro though!

Another reason for wanting a 'sharper' lens is the fact that I don't find (my copy of) the 35mm all that sharp. I don't know how to describe it. But the problem is most prominent when I'm using it in my studio. The more flashes, the more obvious the problem becomes. You know how some lenses have this blue hotspot in the center? Well it's like my DA 35 has the blue hotspot all across the frame. I'll post two pictures tonight when I get home for comparison, one with the 35 and one with another lens that's set to 35mm.

So, maybe I'm better off replacing my SMC DA 35 ltd by a HD DA 35 ltd for its superior coatings?

The 35mm macro isn't amazingly sharp outside of the center. See:

Pentax-DA 35mm F2.4 AL Review - Sharpness | PentaxForums.com Reviews

That said, pretty much all modern primes are "really good" and I doubt pixel level sharpness will make or break a shot in all but extreme cases

Go for the 100mm if you want to focus on close-ups. It sounds like you like the versatility of the 35mm, though, which makes it a tough choice I guess.

[BigMackCam]

That looks very much like a loss of contrast due to haze, which I've never heard of on a DA35 f/2.8 before, but it's possible. Loss of contrast would also make the lens appear less sharp. Have you done the "flashlight test" to see if the optics all look good?