Hi Guys,
I am new to the forum and a new proud owner of a Pentax K-50.
I mainly purchased this camera (in a 2 lens kit) for taking pictures of my saltwater reef tank, so lots of macro shots of close up corals, etc. Some of the corals will be just a few inches away and others as far back as 12-15"

What would be my best choice for a lens for this? I have a bit of a limited budget, $200 or less, or fairly close to that, and used is fine.

Thanks a lot in advance!

[jatrax]

At that budget you are going to be limited to manual focus mostly. It also depends on how much you want to get in the frame. A Pentax-A 100mm Macro would be a good choice or if you can work with 50mm the Pentax-A 50mm macro is very nice.

Another one to look at would be the Pentax-F 35-70 it is autofocus and while not a true macro does have a useable close focus mode at 70mm. It is also available at $70 or so most of the time.

[zeekthegeek]

Great thanks for that info!
I should of mentioned that I would prefer a manual focus since I would be having fish and other moving creatures/particles in the water column that would make an auto focus bounce around too much. Typically the shots I would likely to be taking would not require much to be in the frame. I attached a pic to give an idea of what I would likely be doing and hoping to achieve.
I would not rule out an auto focus for other purposes like outdoor macro shots that I most likely will be doing as well.
The whole shot below would be about 1.5-2 inches of the coral.

[GUB]

Great thanks for that info!
I should of mentioned that I would prefer a manual focus since I would be having fish and other moving creatures/particles in the water column that would make an auto focus bounce around too much. Typically the shots I would likely to be taking would not require much to be in the frame. I attached a pic to give an idea of what I would likely be doing and hoping to achieve.
I would not rule out an auto focus for other purposes like outdoor macro shots that I most likely will be doing as well.
The whole shot below would be about 1.5-2 inches of the coral.

Awesome image.
Because you are photographing through the glass or water surface my instinct would be to have as short a focal length as possible to do the job so that the lens is close to the glass (or water). This should give you more control over light reflections and surface imperfections. It may well be that the flexibility of a zoom is a real plus here to keep you close. I see your image here is at 200mm with a FF sensor so something around 135mm would do that on the K3.
A range of cheap M series primes may do the trick. (50mm1.7---- 135mm3.5 -- 200mmf4)

[Dukeatoakland]

I use the FA 50mm 2.8 Macro on a K-50 at work. It's a very good lens and very cheap.

[zeekthegeek]

Thanks again for this great info. I do need to say that image was not taken by me, it is one from the net that represented what I want to be able to do with my camera and lens

[GUB]

Thanks again for this great info. I do need to say that image was not taken by me, it is one from the net that represented what I want to be able to do with my camera and lens

Ahh then use your kit zooms till you get an idea of the most useful focal length.

[jatrax]

One thing you might want to check into is the horizontal field of view at various focal lengths.
For example a 50mm lens 12" away from the subject will capture a horizontal view of about 6". A 100mm will get you about 3".
Calculator here: http://www.tawbaware.com/maxlyons/calc.htm

You can always back up but in your case you will not be able to get any closer than the glass allows. And GUB has a good point, I think it is standard to use a rubber lens hood or other shield touching the glass to eliminate reflections. Which means you won't be able to move back either.

[GUB]

Ahh then use your kit zooms till you get an idea of the most useful focal length.

I always forget that the kit lens are useless with extension tubes (no A control).
You are stuck with close up filters.
Older zooms like the F35-70 jatrax mentions are so cheap they are free and have aperture control when you have tubes on. Something like a 100-300 as well and all until you know what focal lengths suit you most for your prime lens choice in the future.

[Outis]

I'd highly recommend the 100mm f/4.0 M macro lens. I have it, and I think it's the bee's knees-- yeah, it's manual aperture and manual focus, but it doesn't matter how long I need to set up my shots, and it's really sharp. There are 100mm f/2.8 macros, but the depth of field is extremely thin at f/4.0 anyway, and so I don't think I'd end up taking advantage of the extra-wide aperture. You can find 100mm M macros at KEH for $100-200.

[dms]

I would get the adaptall-2 SP 01 lens (35-80mm) plus a 2x TC (tamron or perhaps better would be Vivitar macro). This cover a lot of distances and magnification and the image likely will not be better with the best macro--as you are shooting through glass. Zoom is better as you can adjust your focus and size of image w/o moving the tripod. It also will be (for PKA adapter, lens, and vivitar 2x macro) about $175.

[zeekthegeek]

Guys thanks again for all this great info and options. What a great forum this is for the sheer wealth you all offer to someone new at this like myself.
Now I have so many choices I am not sure which one to go with. That's awesome! lol

[Kerrowdown]

if you can work with 50mm the Pentax-A 50mm macro is very nice

+1 on this, I don't really do macro but I picked up my “Femme Fatale” (SMC Pentax-A 50mm F2.8 Macro) last Summer and have been more than happy with the results.