D-FA 100mm Macro

Hi all,

Does anybody have any experience, comments, or criticisms of the SMC Pentax D-FA 100mm Macro 1:2.8 lens. I have the F series equivalent and am wondering if a switch to the 'digital' version would have much benefit. Apart from the 'digital' coating I noticed that this lens has a 49mm filter thread as opposed to 58mm on the F, and I think the FA series lens.

Hi

I too have the SMC Pentax FA 2.8 100mm macro, which is a beaut, and although I have no experience with the new 'digital' version, I have seen a test report recently (Practical Photography May 06), measured against others currently available from Nikon, Canon, Sigma etc.. & out of the 6 tested it was given the worst rating!
Although you can take some of these reports with a pinch of salt and really need to assess equipment yourself, I personally am happy to stick with the FA model and indeed generally speaking I believe that the current crop of available Pentax lenses simply do not live up to the great classics of years gone by.
I am hoping that with the launch later this year of a much more professional DSLR aimed at the pro-sumer market, will also re-launch a full range of Pentax lenses with wide aperture 300 - 600 's available as in the past but now so hard to find even 2nd hand. Plus, I have spoken recently to Sigma UK and they advise that if the new Pentax 10.2 mp DSLR due out does sell well, they will consider making PAF fit available in their own range of long telephotos, that are now restricted to Canon, Nikon and Sigma fittings.

Philip

Thanks for the info Philip. I currently use the F series lens but I quite like the idea of the lock on the FA, and I think its on the D-FA too. I think maybe I'll look for a FA version to replace my F.

I have noticed that the anti-ghosting coating on the new DA and D-FA lenses is very good. I'm getting much more contrasty/colour saturated results with my shiny new 16-45mm DA lens than any of the older Pentax glass. Of course, it could just be that my older lenses need a good clean.

Thanks for your input.

pentax forgets to mention that the new d lenses have a flourite coating....Canon makes a big deal about it...I thoght it prevents cavities....(kidding)...

Have to admit that I've never actually tried one of the new D lenses, as there are none produced as of yet that I require at present. Should the need arise for a new lens within that range I sure will check them out.

When I bought my *istds I opted for, as a main lens, the Sigma 20-40mm EX ASPH f2.8, as it gave me an effective 30-60mm standard zoom on the APS size sensor and was, and is, still available at a very good knock down price at Warehouse Express. On the LX of course I get the original 20-40mm range.
Very pleased with this lens indeed and with a polarisor + lee nd grad filter set, it's lovely for landscape work. Very versatile and well made.

Philip

Returning to the subject of macro, I've just had a great discovery with my Pentax 100 f2.8 macro.
Before I bought this macro lens (only very recently 2nd hand) I used the Sigma 105mm f2.8 macro with the AF080C ringflash and was very happy.
Some time ago though I decided to try and get greater than 1:1 by adding a teleconverter, because I did not want to bother with either bellows or lens reversing rings due to the added difficulties, especially out in the field.
I have 2 converters : a Sigma 1.4x EX and a Pentax F 1.7x SMC.
What I found was that, most surprisingly, the Pentax 1.7x fit and worked, but the quality of the image degraded somewhat, whereas the Sigma 1.4x EX simply will not fit onto the Sigma 105mm macro? I thought this was rather odd, but accepted it and tended to stick with just the lens and ringflash alone at 1:1 max.
However, today I tried the Pentax 100mm f2.8 macro with the Sigma 1.4x EX and 'Bingo' it fits perfectly and indeed works exceptionally well at full magnification beyond 1:1 on the *istds with the AF080C ringflash even at an aperture of f32 giving perfect exposure (on TTL auto) with all that lovely DOF.
So, as soon as it stops raining, I plan to crawl about in my garden looking for little bugs, tiny plants and getting in some practice and thoroughly enjoying myself.
Still haven't figured out though why the Sigma converter won't fit the Sigma lens?
Any ideas out there?

philip

Phil,
Sounds strange. But maybe that's just Sigma.
I have used the SMC-F100 with full auto extension tubes too
http://www.ephotozine.com/gallery/showlargepic.cfm?photoid=261457
I did also try with the 1.7xAF converter too - but you're getting into microscope country then!
Matt

Yes indeed Matt, you can of course keep on adding anything that fits to get closer and closer, but after so much it really becomes pretty impratical, especially for outdoor work, with the focussing and DOF issues.
I think that, for me, with what I do, I am now happy to use the 100 macro plus 1.4x converter as my maximum close up equipment. I do also have a set of auto extension tubes, but rarely use them these days. They were my first go at macro work with my LX and an old manual 50mm 1.7, without a ringflash and boy did I struggle, although thoroughly enjoyed myself and the steep learning curve that came!

Philip

I would just like to add that the FA 1:2.8 100mm macro is a magnificent lens. They still come up on Ebay from time to time, and are well worth the price.

Well, on reflection I suppose that depends on what the price is. Mine cost me £166; there is one on Ebay currently for £340.00! There is also a dental macro for £272. I sold mine to Arthur Dent last year for less than half that. Should have hung on.

G

May just be worth mentioning whilst we are on the subject of macro/extreme close ups that this is when you find out just how much dust can get onto a DSLR sensor no matter how careful you are.
Because you are focussing so close and hopefully at a very small aperture to get the required DOF, the magnification factor also magnifies tiny bits of dust on the sensor that you would not normally see on general photography shots.
I thought I had kept my *istds sensor pretty clean with a regular blast from a Giotto rocket blower, but the shots I took the other day with the 100mm macro, plus 1.4x converter on closest focus (above 1:1) at an aperture of f22 showed tiny spots here and there that I don't see on other general shots e.g landscapes etc... I have given it another blast with the blower and will test again, but I suspect that you reach the point that some stubborn bits won't go away. I will never use any sort of solutions to clean the sensor (no matter what they advertise) and if it became a real problem then I would prefer to send it to Pentax for professional sensor cleaning, although I expect it would only re-occur no matter how careful you are and is a costly service.
Maybe in time all manufacturers with have developed a work around system, similar to the one Olympus use, to prevent dust attaching to the sensor. We shall see.

Philip

PS I thought at first that sensor dust would show up equally on whatever type of shot you took, as the image is simply recorded on the sensor and the magnification factor is within the lens itself. However, I did find a macro specialist website recently (can't remember name) who also warned that a dirty/dusty sensor is especially a problem with extreme close up work. Maybe there is someone more techy savvy here on the forum who can explain?

Philip,
As far as I'm aware it's just down to the aperture used. I can get loads of dust spots and specks when using f/22 on landscapes.

The worst is when using a pin hole! This showed up just how filthy my CCD was

However, it does also depend on having a smooth area to notice the dust spot. Skies are a good one. But macros are more susceptible in that you are much more likely to have smooth areas because of the extremely shallow DoF.

When you think about it there is absolutely no difference between the light hitting the sensor from a wide angle lens and that from a macro. And ideally for CCDs the light should hit the sensor at right angles.

Regarding cleaning - apart from the rocket blower, I've used the "homebrew" approach many times using PecPads and a drop of Eclipse cleaning fluid. This was good, but I've recently had the DSLRClean recommended (from http://www.intemos.com/ ) and found them extremely good. After nearly three years of solid use (and >14000 shots) the CCD still needed a reallly good clean. I went through 2 sticks using their cleaning solution, and 2 dry sticks. Now I'm pretty much dust free, save for extremely small stuff.

The surface of the CCD is tough - you just have to be careful not to drag dust across it. One of the worst things that can happen is the batteries fail while you're cleaning - because then the shutter gets damaged. (But the *ist-D starts bleeping furiously at you just before the batteries completely go!)

Matt

What they concluded was "results are good once you stop the lens down from f2.8".

This is no major surprise as it could apply to almost every Pentax prime lens ever made

There is no earthly point in shooting macro wide-open. f11 or smaller is my motto, so comparing macro lenses wide open just demonstrates how stupid the reviewer is.

G

Hi
My first post
I have been a very very amateur photographer for over 40 years with both Pentax and Minolta – more a happy snapper with delusions really, but I ended up with a Pentax *istD with a couple of zoom lenses and a set of extension tubes
Now I want a suitable prime lens for Macro work – yes I know this question has been asked a hundred times, but forgive me if my last remaining brain cell is a bit slow on the uptake.
As far as I can see, the current new choice is between 50mm (Pentax) and 100mm (Tamron) and 105mm (Sigma)- all 1:1 Macro. All of course are subject to the 1.5X factor making it 75mm or 150mm. The main differences (apart from price) seem to be the camera to subject distance and DOF. The shorter the FL, the closer the focus but the greater the DOF.
I have no specific speciality in terms of subject; it could be a close-up of flower, or the dimple on the pimple of a fly’s left knee.
However, people talk about second hand lenses at remarkably low prices which confuses the issue even more.
So, first question for all the experts – what are your experiences with the different options?
Second question – what are the limitations of older S/H lenses? How do I know that they would work with the *istD. How do I get a manual threaded lens attached to my camera without damaging either of them.? Is there anything in between the old M42 mount and the moderm AF mount that might be suitable?
Any advice, guidance, counselling etc would be most welcome
Graham

Graham,
First off - if you have extension tubes, then any of the old K-mount 50mm f/1.7 lenses would work very well and should be a lot sharper than any zoom. Something like the SMC-A 50mm/f1.7, or SMC-F 50mm/f1.7 or SMC-FA 50mm/f1.7.
The F and FA are autofocus, while the A is manual focus. All three work great on the *ist-D.

If you want a dedicated macro lens, then these are some points to bear in mind:
* The SMC-F and SMC-FA 100mm/f2.8 lenses are superb. But heavy Built in lens hood. Astonishingly sharp, and superb for portraiture too (though sometimes it shows just too many skin blemishes!!). Will work fine on extension tubes as well for super close work.

* The new macro lenses (both 50mm and 100mm) don't have aperture rings. This is a problem for extension tubes, unless you have tubes which have electrical contacts.

If you want super, super close, then a 50mm/f1.7 prime reverse mounted will be astounding

Expect to pay around £200 for an SMC-F 100mm/f2.8. The 50mm/f1.7 prime in autofocus is around £70, while in manual should be around £30? (saw one go for £9.50 on ebay!)

You really do need to know a little more about your anticipated subject first. The longer macro lenses (like the 180mm) will be much easier for insects. A 50mm macro will be very difficult for insects - you have to get too close and they zip off!

Personally I love the SMC-F 100mm/f2.8, tho' it is a big brute. Works a dream on both my *ist-D and *ist-DS.

Generally any K-mount lens will work just fine on the *ist-D. Best to stick to the SMC-A (man focus), SMC-F (autofocus), SMC-FA (autofocus) and SMC-DA (new digital) series (the older SMC-M are manual everything and are a bit of a pain but will work).
That's the great thing about Pentax - superb backward compatibility!! If you are aiming for non-Pentax, then make sure the lens has an "A" setting on the aperture ring and you should be fine... though I'd strongly recommend trying to find Pentax SMC lenses

Hope that helps!
Matt