[luxrising]

I'm looking for a 1:1 macro lens to shoot 35mm film negs with my K-5iis. The least expensive option that is at least decently sharp would be ideal as this lens will likely be dedicated to only shooting negs.
I'm not interested in macro tubes, bellows etc., I'd prefer a 1:1 macro lens. AF or MF is fine, new or used is fine though A setting on aperture ring would be preferred. That said, budget is definitely a priority.
Any suggestions would be greatly appreciated!
Best,
Derek

[boriscleto]

Why do you need 1:1? Unless you want a 24x18 section of a 36x24 negative?

[vonBaloney]

Well, without bellows/slide duplicator/whatever, how are you going to hold, light, and shoot the negatives? Homemade device?

[robthebloke]

I'd hunt down a 50mm DFA f2.8 (or one of the older FA/F versions)

[UncleVanya]

What working distance do you want to use?

[robthebloke]

These aren't exactly budget choices at $300-$400 used, and for duplicating slides, the AF is pretty pointless. If looking for a cheaper 2.8, the A also has great picture quality for half as much.

On eBay in the uk right now, I can pick up a BIN dfa50 for £169 (microglobe sell them new for £219). There is also an auction for the A version with a *starting* price of £120 (they usually go for £140 ish). Only the 50M f4 goes for less than £100. Claiming the 50mm A is half the price, is bending the truth quite a bit

[luxrising]

Thanks for the replies guys. I'll add a few more specifics...
I shoot negs now on a small light box with the camera mounted on tabletop tripod pointing directly down on the light box. I have a DIY neg strip holder that is mounted on the light box that I can quickly pull the neg strip through. Shooting distance is flexible but realistically not more than 36". My budget is under $300 but under $200 would be excellent. I've seen the Tamron 90mm 2.8 macro and Sigma 105 macro in K mount going for not much over $200 on ebay, thought they might be decent options.
Best,
Derek

[vonBaloney]

Yeah, with that setup, something around a 100mm macro is what you need. It need not be 1:1 though, a 1:2 macro would do just fine. The "plastic fantastic" 100/3.5 macro (manual focus or autofocus version -- the MF version is a little better built) sold under various names -- Vivitar, Promaster, Bower, even Pentax -- would be a good budget choice. It is cheaply built, but a good working copy is an excellent performer. They can often be found as low as $60 to about $100, depending on MF or AF and whether they have the often missing 1:1 achromat adapter (which you wouldn't need)...

Correcting myself, I think you would want a lens (or a lens with adapter or tube) that goes to 1:1. I was thinking of a recent setup I was using with a 90mm 1:2 macro lens to duplicate slides that was set short of the minimum focus distance, but I am remembering now that I did have an extension on it.

[dms]

For your scenario an older takumar 50mm f/4 that does 1:1 is likely ideal and cost should be moderate--and they come up often. I have the SMC 50 mm f/4 (K) but it only does m=.5, but is the same optics--a very nice lens. The Vivitar 50mm macro did 1:1 and was reputed to be excellent. I believe was a komine made lens and was f/2.5 if I recall right. It is in the PentaxForums lens reviews--but it comes up (much) less often.
Actually you are correct about 1:1, as the m=0.5 will not fill the frame of the K5. Also a 90mm or thereabouts will be a bit too high I think for optimum slide copying with your setup.

Also for slide copying lenses that do well for in the field for macro (like the 100 mm f/3.5 mentioned above--which I also have) are not probably good enough in resolution. Also some other macros (also that do well in the field) may not be flat field enough--the Pentax should be fine on both counts.

[luxrising]

I can pick up a Komine made Vivitar 90 2.8 macro locally but now wondering if 90 is too long for the intended use?

[dms]

It would likely require the camera be about 11 inches above the light box--this for m=2/3.

[luxrising]

dms, can you tell me how you are calculating this? It's a 1:1 lens with minimum focusing distance of 5.7 inches. I'm new to macro and have almost no experience with this.
Thanks,
D

[6BQ5]

I have been using a D-FA 50mm f/2.8 set to around 1:1.5 to photograph my negatives. It works very well. I decided to chase down this lens vs. others because I wanted a sharp modern design. Online test data suggests that ultimate sharpness can be had starting at f/5.6. I shoot at f/6.3 to improve the corners and edges without starting to get into diffraction. You also get the benefit of using this as a general walk-around AF lens when not DSLR scanning your negatives. It's a very sharp lens!

The other lenses will work very well too, I'm sure.

Let us know what you pick!

[dms]

I didn't actually calculate all of it.
-- At 2/3 magnification (you want to reduce the 24x36mm to a 18x24 mm, and 2/3 of 36 is 24) the required lens extension--whether it is by adding tubes or lens mount extension--you are adding 2/3 times 90mm or 60mm, or just over 2 inches (if it was m=1 it would be 90 mm of extension). BTW m=2/3 is the same as 1/1.5 used by 6BQ5 above.
-- Then the distance from the focal point to the target can be calculated--but I simply looked up the "typical working distance" for a 90 mm lens in Lefkowitz The Manual of Close-Up Photography which was about 7 inches (for m=2/3=0.67).
-- You also have the lens depth and distance from rear lens to sensor which is likely 3 inches.
Thus 2+7+3 inches=12 inches.

In your case you could have found a table of focus distances and gotten the value--as focus distances are from the camera. But you don't have it for this camera (I mean lens), and even for a similar lens may not have it except at the close limit (m=1 or 1/2 typically). BTW newer lenses often use internal focusing and not just extension--thus they get shorter FL as you get close--and thus shorter working distances. Usually (in the field) shorter working distances are problematic--but for your application with the light from behind the target, shorter working distances are much preferred. After all you don't want to use a higher tripod and a step ladder--or have to put the light box on the floor. That (working distance considerations) is also why I think 50mm FL is best.

[luxrising]

Thanks dms for the detailed explanation!
Boris, that sounds like a nice option, maybe I'll keep a lookout for one used. That said, I don't shoot digital except for scanning my film negs so the AF isn't really important to me but a readily available, modern design does sound appealing.