[PFFJazzMan]

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I'm really new to this, having done primarily P&S with low-res Olympus cameras in the past. On occasion I do closeup and detail photos such as this,



and I'm wanting to get a lens/flash setup for my new K100D that will do this kind of shot, or even greater magnification. My current lens is an SMC DA 18-55 (the kit lens) and I have a Tamron 28-300 on the way, as well as a Sigma 530DG super. I think with the addition of a really good close-up lens my emerging LBA will be satisfied.

I don't exactly know what to search for on the forum, so suggestions and advice on that would also be appreciated.

Thanks!

[Blue]

For that type of close-up work, a vintage Pentax 50mm macro lens, A or M versions would be a possibility. Also the Sigma 50mm macro is not to price new ~$249 and is AF and 1:1 and is a good lens, especially for your body. If you want the ultimate bling, the Pentax DA 35mm ltd macro is an option as is the Sigma 70mm macro. If you every plan on doing macro on things require a longer working distance, such as 'bugs', something 90mm or longer is the way to go although the 70mm mentioned would work.

As far as currently produced dedicated macro Lenses:

Pentax 35mm ltd
Pentax D fa 50mm f2.8
Pentax D FA 100mm f2.8

Sigma 50mm f2.8 EX DG
Sigma 70mm f2.8 EX DG
Sigma 105mm f2.8 EX DG
Sigma 180mm f2.5 EX DG

Tamron 90mm f2.8

Zeiss 100mm macro (don't ask the price)

These are all good lenses.

As far as the used market goes, there are a plethora of choices there also.

Tamron 90mm several models including the adaptall 2 52B and b2BB etc.
Pentax 50mm f4: A, M, K and several m42 Takumars as well
Pentax 100mm f4: A, M, and several M42 Takumars as well
Voightlander Lanthar 125mm
Vivitar 105mm f2.5 Series 1 (Kiron and Lester Dine versions of this lens are out there as well) These have a cult following and can be pricey

Pentax A* 200mm f4 (these are nice but bring a price > $1500)
Pentax FA* 200mm f4 (these are not only pricey but hard to come by and are almost mythical)

There are a few others as well such as but not limited to Vivitar 90mm and a Tokina 90mm.

[madphys]

If you want to take pics only of non-living things or plants then you might get Macro extension tubes (If I'm not mistaken then you might get ones that support AF but I might be wrong) and some external fixed lighting sources.

If you want to do macro work with macro lens (1:1 magnification) then you should get one - I would suggest something with greater focal length (important for insects and other little creatures - you will get greater work distance).

Some of the popular options are:
1) Tamron 90mm F2.8
2) Sigma 70mm F2.8
3) Sigma 105mm F2.8
4) Sigma 180mm F3.5
5) Pentax DFA 100mm F2.8

In addition to macro lens you might want to purchase a macro ring flash - sigma has something to offer, Metz also, and Pentax is going to release genuine ring flash any day now (relatively speaking).

Also you will find that for stills it is better to use tripod. After that maybe you will realize that it would be nice to have Macro focusing rail slider. Maybe extension tubes won't give you enough versatility so maybe later on you will start thinking about macro bellows... Who knows

Good luck!

[MrApollinax]

For that type of close-up work, a vintage Pentax 50mm macro lens, A or M versions would be a possibility. Also the Sigma 50mm macro is not to price new ~$249 and is AF and 1:1 and is a good lens, especially for your body. If you want the ultimate bling, the Pentax DA 35mm ltd macro is an option as is the Sigma 70mm macro. If you every plan on doing macro on things require a longer working distance, such as 'bugs', something 90mm or longer is the way to go although the 70mm mentioned would work.

As far as currently produced dedicated macro Lenses:

Pentax 35mm ltd
Pentax D fa 50mm f2.8
Pentax D FA 100mm f2.8

Sigma 50mm f2.8 EX DG
Sigma 70mm f2.8 EX DG
Sigma 105mm f2.8 EX DG
Sigma 180mm f2.5 EX DG

Tamron 90mm f2.8

Zeiss 100mm macro (don't ask the price)

These are all good lenses.

I can vouch for the non-DG versions I have bolded in red above. Great close focus lenses. Here are two hand-held shots i took with my K100DS:

50mm 2.8:


105mm 2.8:


I have since traded the 50mm 2.8 Macro lens for a FA50 f/1.4 lens. The 105mm is a better working length for the type of shooting I do.

[PFFJazzMan]

I'm really sure I don't understand lens nomenclature now.

I always thought that the lower the number the better for closeup work; e.g. an 18mm would be able to do much closer work than, say, a 100mm. A linear relationship, as it were.

Time to do more research...

[MrApollinax]

Macro lens allow for close-up focusing. While there is a linear relationship between working distances and Focal Length if you are using a true "Macro" lens your working distance will be quite small. My 105mm for example has a working distance @ 1:1 of .313m (~12in) from the focus plane. The 50mm that I talked about in my earlier post had a working distance @ 1:1 of .187m (~7.5in) from the focus plane. By focus plane I mean from the sensor so basically take those numbers to mean "from the back of the camera." Also once you get to the 1:1 magnification range your lens will have extended out quite a bit so from the front of your lens to the subject will be a very short distance.

[PFFJazzMan]

So what would be suggested if I want working distances (from lens to subject/object) no closer than 15cm or so and the ability to resolve features as fine as .01-.02mm? I also need DOF of at least 10-20mm because I may not be able to get the camera axis normal to the surface being photographed.

For reference, IIRC the picture I posted above was taken with an Olympus C-720 P&S, ~3MP.

[audiobomber]

I'm really new to this, having done primarily P&S with low-res Olympus cameras in the past. On occasion I do closeup and detail photos such as this,

The photo you've shown is not that difficult to achieve. You could likely get that fov and quality with your 28-300 and some cropping. Any "real" macro lens (real meaning 1:1 macro as opposed to close-focussing lenses marketed as macro), can get closer than this and offer superb image quality. As others have said, the longer the lens, the longer the working distance.

I'll present another alternative for you. The Raynox 150 mounted on the end of your 18-300 would give you strong macro capability (up to 1.4:1) and would not compromise the optics. Working distance is more than I get with my D FA 100mm macro. It's very impressive for $50.00.

Raynox | DCR-150, 1.5x Macro Lens | DCR-150 | B&H Photo Video

As you've noted, you will need to use small apertures and add light. The Sigma flash mounted on the camera, preferably with a diffuser or at least the wide-angle panel, will do the job. You can get better results by mounting the flash on a stand or tripod off the camera.

[PFFJazzMan]

Ok, now I'm even more confused than before. I just tried to take a picture inside my car of a connector. I thought I could do this with my Tamron 28-300 but the closest I could focus was about 17" from lens to subject, and unfortunately that put the back of the camera through the windshield. The above picture was taken about 4-5" from subject with a P&S.

Maybe if I said what I wanted someone could suggest a set of lens specifications for me to shop for? What I think I need is a DOF of at least 4-5mm with 4 pixels per .001" subject feature size. That would make the above dime about 2,000 pixels high, or full vertical frame size on my K100D. I need to have a maximum lens to subject distance of around 30cm. Does this sound possible?

[MrApollinax]

Like it was said earlier in the thread: For that kind of work you will need a true Macro lens or adapter. The distances you are talking about are referencing from the front of the lens to the subject? Most distances are measured from the sensor to the subject. From your post above this i what I think you are trying to do:



This is straight conversion from PEF to JPEG and resized for web, no cropping. I used my 105mm and the front of the lens was about 4 or 5 inches from the Aussie nickel (didn't have a dime on me but they are roughly the same size). From the back of the camera to the subject was about a foot or so. There are a lot of excellent Macro shooters here who might be able to tell you off the top of their heads which lens to buy based on your working distance requirements.

[newarts]

So what would be suggested if I want working distances (from lens to subject/object) no closer than 15cm or so and the ability to resolve features as fine as .01-.02mm? I also need DOF of at least 10-20mm because I may not be able to get the camera axis normal to the surface being photographed.

For reference, IIRC the picture I posted above was taken with an Olympus C-720 P&S, ~3MP.

A 10.2mp sensor is about 1932 pixel pairs wide. You want to have the image that fills the sensor be .01mm times the number of pixel pairs or about 19mm. Great! this puts you at about a magnification requirement of 1:1.

The relationship between distance from the lens, W, magnification, m, and focal length f is:

W=F(1+1/m)

Substituting the magnification you need results in.

W=2F

You say you need a working distance of 150mm. Lets say that the actual lens center is recessed by 10mm, so you've got to have a total working distance of 160mm to have 150mm clear.

That indicates you need a minimum focal length of 160/2=80mm.

You need something like an 80-100mm 1:1 macro lens. Don't worry much about f-stop, auto-focus & the like as you'll likely want to manually focus & stop down a lot for DOF.

DOF is a real problem; at 1:1 magnification it'll be about (F-stop/10) mm deep. That is, F6 will give you about 0.6mm depth of field, F/10 about 1mm etc.. (depending on how tolerant to fuzziness you are.)

There is nothing you can do about the depth of field situation except to take a sequence of photos at constant magnification, moving the camera between exposures, then use "Focus Stacking" software to assemble an in-focus image.

For this you'll want a focusing rack.

What you've outlined is practical without getting too exotic, but it is by no means trivial.

Dave

PS There's a nice pentax M 100/4 dental macro lens on ebay now for Buy it Now at $189us
http://cgi.ebay.com/Pentax-Macro-100mm-f4-Lens-w-dental-scale-K-mount_W0QQit...A1%7C294%3A200

[PFFJazzMan]

That's exactly what I was after! WRT subject distances, 99% of what I do would involve "cooperative" subjects so other than optical distortions the only things I'm concerned with are DOF and how much room I'll need for lens/camera/cranium. I do technical support for a car forum and many pictures I'll want to take will be around/inside/under one of my Fieros. I still have a small 1MP Olympus P&S that I can use where I've only got a few inches of room adjacent to the subject. Since all of what I post will be cropped to a maximum of 640 pixels wide, IQ isn't that big of an issue other than giving me resolution when I crop.

The more I learn here the more amazed I am with P&S cameras getting to 10X optical zoom in such a small package with generally good results. A lot of engineering goes into one of those.

[newarts]

The depth of field for a particular f-stop and magnification changes with the square of sensor size. Therefore a P&S with a 5mm sensor has almost 50 times more depth of field than a full frame camera.

A long lens P&S with a good close-up attachment can do nice close-up work.

Macro/close-up discussions often veer off into linguistics. Stick to real dimensions & you'll be ok. Like "I need to image a 20mm wide field" on an APS-C DSLR that's about a 1:1 magnification, on a 5mm P & S that's a 1:4 close-up, easily obtainable with a diopter close-up lens. If you've got plenty of light it hardly matters what size sensor you use.

Dave