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10-25-2009, 05:08 AM   #1
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100mm 2.8 Macro - A vs. F

For some years I own the A version which is one of my favorites. To my eyes it can deliver really excellent pictures. But recently I got the F (an offer I could not refuse ) and I feel I have to choose between them.

The handling is obviously completely different. The A is compact compared to the F beast. AF in the F is nice (in particular on larger distances where the focus turn gets very precise), but the manual focus suffers badly which is important for a macro. The A is beautiful with MF. But these are all things that I can judge myself.

Harder to judge is the IQ. The design is different, I know that. The F/FA is much praised, but I do not see that much data on the A version. Although I would obviously find out over time, does someone have experience with both these lenses?

Please note that I am not a hard core marco shooter. I like to do flowers and butterflies at 1 meter range or so.

10-25-2009, 08:06 AM - 1 Like   #2
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I've had a couple of problems with sensor reflections on my A100/2.8 macro, so I'm kinda careful with what I do with it now. I don't know if the F is better or not.
The A version is an absolute gem, it is one of the sharpest lenses I've used, and gives a 3 dimensionality to macro images that I find very pleasing, so I'm kinda pissed about the reflections off the rear element.
This image shows what I am talking about with the 3dimensionality that I see from the A100/2.8 macro.


10-25-2009, 11:49 AM   #3
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Thanks for posting the photo wheatfield, I have one of those coming Tuesday and I am really looking forward to playing with it. Thanks for the heads up on the reflections.

Last edited by OrenMc; 10-25-2009 at 11:56 AM.
10-26-2009, 02:00 PM   #4
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Hi Wheatfield, thanks for your thoughts. I do agree that the A is really great. You can't go wrong with that one. I am doing some comparison shots between the A and the F and it's really difficult to set them apart image wise. Both are just excellent.

I used the F as a tele on the street today where it helps to get a fast shot through the AF. The IQ is great with nice OOF and good color. Tomorrow I'll try the A in the same setting.

10-31-2009, 10:52 AM   #5
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I just recently picked up an A100/2.8 macro and I also have an F100/2.8 Macro. The first thing I noticed about my copy of the A100 is that it doesn't appear to be as sharp or contrasty at the F100 when used at F2.8. Close down any and I have a hard time differentiating. I'm guessing that the loss of sharpness and contrast wide open is due to sensor reflections? The F100 is crystal clear wide open, with only a very slight drop in sharpness compared to other apertures. The F100 also shows no purple fringing wide open, but the A100 does. This may also be due to sensor reflections?

Just a couple other things I have noticed about the two in terms of lens design. The A100 rear element is much closer to the sensor than the rear element of the F100, which is slightly recessed in the body (the A100 rear element protrudes). This might have something to do with the issues noted above. Also, the pupil ratio (apparent size of the exit pupil / apparent size of the entrance pupil) of the A100 appears to be smaller than the F100 (by my visual inspection), which may indicate that the A100 will give a slight DOF increase in the macro range over the F100 when shooting at the same magnification and F-stop. I don't know the technical specs here so I can't be sure about that.

Also, the focusing on my A100 doesn't feel as well damped as I expected. It is very smooth, but feels "dry" compared to some of my other MF lenses. Compared to my older K and M lenses, and even my A50/1.2 and A24/2.8, it doesn't feel like it has much (if any) lubrication in the helicoid. What do you guys have to say about the feel of the focus? If you think yours is better I may send mine in to get re-lubed and adjusted to make sure everything is proper. It's in great condition so I don't think anything is misaligned, but who knows about sitting around for 15-20 years.

Thanks!
10-31-2009, 05:40 PM   #6
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Jim,

I’ve no experience with the F 100 macro so I have no insights on that one. My A 100/2.8 was purchased new in the 1990s sometime so I’ve had it for about 15 years. After reading your post I took it out and racked it in and out a few times and I would describe the “feel” as firm. The barrel turns smoothly but not as smoothly as my M or K series lenses. On the other hand I don’t have any other lens that extends as far as this one. In this respect it is different than any other lens I own. I suspect this may be normal for this particular lens and I wouldn’t bother servicing it until you had used for a while. Maybe Wheatfield has some additional thoughts on this area? Perhaps it is just peculiar to this lens. Wheatfield has also noted sensor reflection with the A 100 and your observations seem to confirm it. No doubt the protruding rear element is the culprit. That rear element raises another concern. I always take a lot of care mounting this lens to the camera body as it would be easy to scratch that rear element. I don’t use this lens as often as I might but I shall be on the alert for reflections in the future. I do know that this is the sharpest lens in my kit.

Tom G

Last edited by 8540tomg; 10-31-2009 at 05:44 PM. Reason: typo
10-31-2009, 07:52 PM   #7
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Thanks for the reply Tom,

It is a peculiar lens indeed, not sure I've ever seen another lens with the rear element so far back as that. Good suggestion about being careful when changing lenses, it would be a heartbreaker to put a scratch on it. I'll use it for a while before I come to any final conclusions about it's performance, although I agree it appears to be quite sharp when in it's zone. On another note, I really love the look of these A series lenses, I think they compliment the current DSLRs very well, particularly the more classic look of the K-7.

Cheers.
10-31-2009, 08:56 PM   #8
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QuoteOriginally posted by 8540tomg Quote
Jim,


The barrel turns smoothly but not as smoothly as my M or K series lenses. On the other hand I donít have any other lens that extends as far as this one. In this respect it is different than any other lens I own. I suspect this may be normal for this particular lens and I wouldnít bother servicing it until you had used for a while. Maybe Wheatfield has some additional thoughts on this area? Perhaps it is just peculiar to this lens. Wheatfield has also noted sensor reflection with the A 100 and your observations seem to confirm it. No doubt the protruding rear element is the culprit. That rear element raises another concern. I always take a lot of care mounting this lens to the camera body as it would be easy to scratch that rear element. I donít use this lens as often as I might but I shall be on the alert for reflections in the future. I do know that this is the sharpest lens in my kit.

Tom G
On my A100/2.8 Macro, the focusing is as smooth as drawing silk across my wife's breasts.
She has very soft skin, BTW.
And that's all I have to say about that.

Apparently, the A100/2.8 (and IIRC, all the FREE design lenses) are actually a pseudo zoom. i believe when Boz was still on the PDML he teste the lens and found that at 1:1 it was actually closer to an 85mm focal length.
My lens kinda fell apart on me 10 years ago. The aperture started moving very slowly so I sent it in for a CLA. I would suggest that if your focus isn't smooth and well damped that perhaps the lubricants in the helicoid have dried out and that a CLA is in order.

11-01-2009, 05:07 PM   #9
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wheatfield, I have never drawn silk across your wifes breasts so I can't concur with the comparison. But I will say the copy I just received focusing is very smooth also.

One thing that really stuck out when I first recieved mine was how light it is. Compared to the fhe FA and the Viv 105 it seem to be a feather. Its kind of funny because I can look at the specs of a lens and see the weight but until I hold it in my hands it just doesn't register.

I was out with the lens today and I think I experienced some of that sensor reflection. I am wondering, I know the lens elements already sets back quite a ways but would using a hood or a filter help with this at all? I am not really familiar with how this works.

arpaagent, I agree with you as the classic look of the lens with the K7. So much that it has a brother now also, the A 50mm 1:1.2.

Last edited by OrenMc; 11-01-2009 at 05:18 PM.
11-01-2009, 08:22 PM   #10
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QuoteOriginally posted by OrenMc Quote
wheatfield, I have never drawn silk across your wifes breasts so I can't concur with the comparison. But I will say the copy I just received focusing is very smooth also.
Might I suggest then that your life is not as complete as it should be.


QuoteQuote:

I was out with the lens today and I think I experienced some of that sensor reflection. I am wondering, I know the lens elements already sets back quite a ways but would using a hood or a filter help with this at all? I am not really familiar with how this works.

Most of the time, when I'm shooting with my macro lenses, I'm pointing downwards somewhat. With the amount of recess on the A100/2.8, I wouldn't think a hood would be of much use.
I've never tried one on it anyway. I've never had a flare off it before that I htought a hood would fix.
IIRC, one of the things that a "digital ready" lens has is some voodoo lens coatings that stop this sort of flare off the sensor.
11-01-2009, 08:32 PM   #11
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QuoteOriginally posted by OrenMc Quote
arpaagent, I agree with you as the classic look of the lens with the K7. So much that it has a brother now also, the A 50mm 1:1.2.
Oren, I also have the A50/1.2 (and boy do I love it), but had it before I got the A100 macro, so for me the A100 is the new brother to my 50 . I'm thinking that that A24/2.8, A50/1.2, and A100/2.8 Macro will make a really nice 3-lens general purpose MF set up that can handle most situations when I don't want to use a zoom lens. I was thinking about the A100/2.8 non macro instead, but then to handle any close-ups I'd need to carry extension tubes or get a raynox or something.
11-02-2009, 06:37 AM   #12
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Hi guys,

Thanks for all your thoughts and I really like the way this thread has evolved. I've tried sandpaper on my girlfriends breasts and that is definitely not as smooth as focussing the A macro. I'll give silk a try next, but first I need to find a new girlfriend.

But seriously, my copy of the A runs very very smoothly. Much more controlled then the A 50 2.8 macro I also have and just a tad bit lighter then the K 50 1.2. I see it as a major advantage over the F, which just does not feel that controlled. Image-wise I did some 'real life' tests and found the differences to be very small. The F is super sharp at 2.8, but the A is too. I did not encounter the flare problem in hundreds of shots, but I expect it to be a risk when using the A.

All things considering I have decided for the A. Although I expect the F to have the slight edge in IQ, to me the manual focussing tips the balance.

Hopefully I can swap it for an F/FA135. With that length on the street autofocus is a big advantage.
11-02-2009, 08:36 AM   #13
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QuoteOriginally posted by schneider Quote
Hi guys,

Thanks for all your thoughts and I really like the way this thread has evolved. I've tried sandpaper on my girlfriends breasts and that is definitely not as smooth as focussing the A macro. I'll give silk a try next, but first I need to find a new girlfriend.

You just aren't getting it. Sandpaper is fine, but it has to be a very fine grit wet/dry (400 or higher) and is used very gently on the nipples to make them more sensitive.
Do I have to teach you guys everything?
11-02-2009, 02:26 PM   #14
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QuoteOriginally posted by schneider Quote

But seriously, my copy of the A runs very very smoothly. Much more controlled then the A 50 2.8 macro I also have and just a tad bit lighter then the K 50 1.2. I see it as a major advantage over the F, which just does not feel that controlled. Image-wise I did some 'real life' tests and found the differences to be very small. The F is super sharp at 2.8, but the A is too. I did not encounter the flare problem in hundreds of shots, but I expect it to be a risk when using the A.

Personally, I don't recall noticing any flare issues with my A 100/2.8 macro. I don't doubt they happen I just haven't noticed them. Then again, as I've said before, I don't use the lens that often. When I have used it I found it to be super sharp. Are there any conditions in which this flare issue is more likely to occur?

You're right Schneider, this is a good place to keep abreast of things.

Tom G
11-02-2009, 02:32 PM   #15
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There are moments I wish I was a native English speaker Tom G, I know these words but they don't come to me when I'm writing here. But most of the time I am quite happy babbling (double) Dutch.....
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